| 1 | /* Common target dependent code for GDB on ARM systems. |
| 2 | |
| 3 | Copyright (C) 1988, 1989, 1991, 1992, 1993, 1995, 1996, 1998, 1999, 2000, |
| 4 | 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 |
| 5 | Free Software Foundation, Inc. |
| 6 | |
| 7 | This file is part of GDB. |
| 8 | |
| 9 | This program is free software; you can redistribute it and/or modify |
| 10 | it under the terms of the GNU General Public License as published by |
| 11 | the Free Software Foundation; either version 3 of the License, or |
| 12 | (at your option) any later version. |
| 13 | |
| 14 | This program is distributed in the hope that it will be useful, |
| 15 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 17 | GNU General Public License for more details. |
| 18 | |
| 19 | You should have received a copy of the GNU General Public License |
| 20 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 21 | |
| 22 | #include <ctype.h> /* XXX for isupper (). */ |
| 23 | |
| 24 | #include "defs.h" |
| 25 | #include "frame.h" |
| 26 | #include "inferior.h" |
| 27 | #include "gdbcmd.h" |
| 28 | #include "gdbcore.h" |
| 29 | #include "gdb_string.h" |
| 30 | #include "dis-asm.h" /* For register styles. */ |
| 31 | #include "regcache.h" |
| 32 | #include "reggroups.h" |
| 33 | #include "doublest.h" |
| 34 | #include "value.h" |
| 35 | #include "arch-utils.h" |
| 36 | #include "osabi.h" |
| 37 | #include "frame-unwind.h" |
| 38 | #include "frame-base.h" |
| 39 | #include "trad-frame.h" |
| 40 | #include "objfiles.h" |
| 41 | #include "dwarf2-frame.h" |
| 42 | #include "gdbtypes.h" |
| 43 | #include "prologue-value.h" |
| 44 | #include "target-descriptions.h" |
| 45 | #include "user-regs.h" |
| 46 | #include "observer.h" |
| 47 | |
| 48 | #include "arm-tdep.h" |
| 49 | #include "gdb/sim-arm.h" |
| 50 | |
| 51 | #include "elf-bfd.h" |
| 52 | #include "coff/internal.h" |
| 53 | #include "elf/arm.h" |
| 54 | |
| 55 | #include "gdb_assert.h" |
| 56 | #include "vec.h" |
| 57 | |
| 58 | #include "features/arm-with-m.c" |
| 59 | |
| 60 | static int arm_debug; |
| 61 | |
| 62 | /* Macros for setting and testing a bit in a minimal symbol that marks |
| 63 | it as Thumb function. The MSB of the minimal symbol's "info" field |
| 64 | is used for this purpose. |
| 65 | |
| 66 | MSYMBOL_SET_SPECIAL Actually sets the "special" bit. |
| 67 | MSYMBOL_IS_SPECIAL Tests the "special" bit in a minimal symbol. */ |
| 68 | |
| 69 | #define MSYMBOL_SET_SPECIAL(msym) \ |
| 70 | MSYMBOL_TARGET_FLAG_1 (msym) = 1 |
| 71 | |
| 72 | #define MSYMBOL_IS_SPECIAL(msym) \ |
| 73 | MSYMBOL_TARGET_FLAG_1 (msym) |
| 74 | |
| 75 | /* Per-objfile data used for mapping symbols. */ |
| 76 | static const struct objfile_data *arm_objfile_data_key; |
| 77 | |
| 78 | struct arm_mapping_symbol |
| 79 | { |
| 80 | bfd_vma value; |
| 81 | char type; |
| 82 | }; |
| 83 | typedef struct arm_mapping_symbol arm_mapping_symbol_s; |
| 84 | DEF_VEC_O(arm_mapping_symbol_s); |
| 85 | |
| 86 | struct arm_per_objfile |
| 87 | { |
| 88 | VEC(arm_mapping_symbol_s) **section_maps; |
| 89 | }; |
| 90 | |
| 91 | /* The list of available "set arm ..." and "show arm ..." commands. */ |
| 92 | static struct cmd_list_element *setarmcmdlist = NULL; |
| 93 | static struct cmd_list_element *showarmcmdlist = NULL; |
| 94 | |
| 95 | /* The type of floating-point to use. Keep this in sync with enum |
| 96 | arm_float_model, and the help string in _initialize_arm_tdep. */ |
| 97 | static const char *fp_model_strings[] = |
| 98 | { |
| 99 | "auto", |
| 100 | "softfpa", |
| 101 | "fpa", |
| 102 | "softvfp", |
| 103 | "vfp", |
| 104 | NULL |
| 105 | }; |
| 106 | |
| 107 | /* A variable that can be configured by the user. */ |
| 108 | static enum arm_float_model arm_fp_model = ARM_FLOAT_AUTO; |
| 109 | static const char *current_fp_model = "auto"; |
| 110 | |
| 111 | /* The ABI to use. Keep this in sync with arm_abi_kind. */ |
| 112 | static const char *arm_abi_strings[] = |
| 113 | { |
| 114 | "auto", |
| 115 | "APCS", |
| 116 | "AAPCS", |
| 117 | NULL |
| 118 | }; |
| 119 | |
| 120 | /* A variable that can be configured by the user. */ |
| 121 | static enum arm_abi_kind arm_abi_global = ARM_ABI_AUTO; |
| 122 | static const char *arm_abi_string = "auto"; |
| 123 | |
| 124 | /* The execution mode to assume. */ |
| 125 | static const char *arm_mode_strings[] = |
| 126 | { |
| 127 | "auto", |
| 128 | "arm", |
| 129 | "thumb", |
| 130 | NULL |
| 131 | }; |
| 132 | |
| 133 | static const char *arm_fallback_mode_string = "auto"; |
| 134 | static const char *arm_force_mode_string = "auto"; |
| 135 | |
| 136 | /* Number of different reg name sets (options). */ |
| 137 | static int num_disassembly_options; |
| 138 | |
| 139 | /* The standard register names, and all the valid aliases for them. Note |
| 140 | that `fp', `sp' and `pc' are not added in this alias list, because they |
| 141 | have been added as builtin user registers in |
| 142 | std-regs.c:_initialize_frame_reg. */ |
| 143 | static const struct |
| 144 | { |
| 145 | const char *name; |
| 146 | int regnum; |
| 147 | } arm_register_aliases[] = { |
| 148 | /* Basic register numbers. */ |
| 149 | { "r0", 0 }, |
| 150 | { "r1", 1 }, |
| 151 | { "r2", 2 }, |
| 152 | { "r3", 3 }, |
| 153 | { "r4", 4 }, |
| 154 | { "r5", 5 }, |
| 155 | { "r6", 6 }, |
| 156 | { "r7", 7 }, |
| 157 | { "r8", 8 }, |
| 158 | { "r9", 9 }, |
| 159 | { "r10", 10 }, |
| 160 | { "r11", 11 }, |
| 161 | { "r12", 12 }, |
| 162 | { "r13", 13 }, |
| 163 | { "r14", 14 }, |
| 164 | { "r15", 15 }, |
| 165 | /* Synonyms (argument and variable registers). */ |
| 166 | { "a1", 0 }, |
| 167 | { "a2", 1 }, |
| 168 | { "a3", 2 }, |
| 169 | { "a4", 3 }, |
| 170 | { "v1", 4 }, |
| 171 | { "v2", 5 }, |
| 172 | { "v3", 6 }, |
| 173 | { "v4", 7 }, |
| 174 | { "v5", 8 }, |
| 175 | { "v6", 9 }, |
| 176 | { "v7", 10 }, |
| 177 | { "v8", 11 }, |
| 178 | /* Other platform-specific names for r9. */ |
| 179 | { "sb", 9 }, |
| 180 | { "tr", 9 }, |
| 181 | /* Special names. */ |
| 182 | { "ip", 12 }, |
| 183 | { "lr", 14 }, |
| 184 | /* Names used by GCC (not listed in the ARM EABI). */ |
| 185 | { "sl", 10 }, |
| 186 | /* A special name from the older ATPCS. */ |
| 187 | { "wr", 7 }, |
| 188 | }; |
| 189 | |
| 190 | static const char *const arm_register_names[] = |
| 191 | {"r0", "r1", "r2", "r3", /* 0 1 2 3 */ |
| 192 | "r4", "r5", "r6", "r7", /* 4 5 6 7 */ |
| 193 | "r8", "r9", "r10", "r11", /* 8 9 10 11 */ |
| 194 | "r12", "sp", "lr", "pc", /* 12 13 14 15 */ |
| 195 | "f0", "f1", "f2", "f3", /* 16 17 18 19 */ |
| 196 | "f4", "f5", "f6", "f7", /* 20 21 22 23 */ |
| 197 | "fps", "cpsr" }; /* 24 25 */ |
| 198 | |
| 199 | /* Valid register name styles. */ |
| 200 | static const char **valid_disassembly_styles; |
| 201 | |
| 202 | /* Disassembly style to use. Default to "std" register names. */ |
| 203 | static const char *disassembly_style; |
| 204 | |
| 205 | /* This is used to keep the bfd arch_info in sync with the disassembly |
| 206 | style. */ |
| 207 | static void set_disassembly_style_sfunc(char *, int, |
| 208 | struct cmd_list_element *); |
| 209 | static void set_disassembly_style (void); |
| 210 | |
| 211 | static void convert_from_extended (const struct floatformat *, const void *, |
| 212 | void *, int); |
| 213 | static void convert_to_extended (const struct floatformat *, void *, |
| 214 | const void *, int); |
| 215 | |
| 216 | static void arm_neon_quad_read (struct gdbarch *gdbarch, |
| 217 | struct regcache *regcache, |
| 218 | int regnum, gdb_byte *buf); |
| 219 | static void arm_neon_quad_write (struct gdbarch *gdbarch, |
| 220 | struct regcache *regcache, |
| 221 | int regnum, const gdb_byte *buf); |
| 222 | |
| 223 | struct arm_prologue_cache |
| 224 | { |
| 225 | /* The stack pointer at the time this frame was created; i.e. the |
| 226 | caller's stack pointer when this function was called. It is used |
| 227 | to identify this frame. */ |
| 228 | CORE_ADDR prev_sp; |
| 229 | |
| 230 | /* The frame base for this frame is just prev_sp - frame size. |
| 231 | FRAMESIZE is the distance from the frame pointer to the |
| 232 | initial stack pointer. */ |
| 233 | |
| 234 | int framesize; |
| 235 | |
| 236 | /* The register used to hold the frame pointer for this frame. */ |
| 237 | int framereg; |
| 238 | |
| 239 | /* Saved register offsets. */ |
| 240 | struct trad_frame_saved_reg *saved_regs; |
| 241 | }; |
| 242 | |
| 243 | static CORE_ADDR arm_analyze_prologue (struct gdbarch *gdbarch, |
| 244 | CORE_ADDR prologue_start, |
| 245 | CORE_ADDR prologue_end, |
| 246 | struct arm_prologue_cache *cache); |
| 247 | |
| 248 | /* Architecture version for displaced stepping. This effects the behaviour of |
| 249 | certain instructions, and really should not be hard-wired. */ |
| 250 | |
| 251 | #define DISPLACED_STEPPING_ARCH_VERSION 5 |
| 252 | |
| 253 | /* Addresses for calling Thumb functions have the bit 0 set. |
| 254 | Here are some macros to test, set, or clear bit 0 of addresses. */ |
| 255 | #define IS_THUMB_ADDR(addr) ((addr) & 1) |
| 256 | #define MAKE_THUMB_ADDR(addr) ((addr) | 1) |
| 257 | #define UNMAKE_THUMB_ADDR(addr) ((addr) & ~1) |
| 258 | |
| 259 | /* Set to true if the 32-bit mode is in use. */ |
| 260 | |
| 261 | int arm_apcs_32 = 1; |
| 262 | |
| 263 | /* Return the bit mask in ARM_PS_REGNUM that indicates Thumb mode. */ |
| 264 | |
| 265 | int |
| 266 | arm_psr_thumb_bit (struct gdbarch *gdbarch) |
| 267 | { |
| 268 | if (gdbarch_tdep (gdbarch)->is_m) |
| 269 | return XPSR_T; |
| 270 | else |
| 271 | return CPSR_T; |
| 272 | } |
| 273 | |
| 274 | /* Determine if FRAME is executing in Thumb mode. */ |
| 275 | |
| 276 | int |
| 277 | arm_frame_is_thumb (struct frame_info *frame) |
| 278 | { |
| 279 | CORE_ADDR cpsr; |
| 280 | ULONGEST t_bit = arm_psr_thumb_bit (get_frame_arch (frame)); |
| 281 | |
| 282 | /* Every ARM frame unwinder can unwind the T bit of the CPSR, either |
| 283 | directly (from a signal frame or dummy frame) or by interpreting |
| 284 | the saved LR (from a prologue or DWARF frame). So consult it and |
| 285 | trust the unwinders. */ |
| 286 | cpsr = get_frame_register_unsigned (frame, ARM_PS_REGNUM); |
| 287 | |
| 288 | return (cpsr & t_bit) != 0; |
| 289 | } |
| 290 | |
| 291 | /* Callback for VEC_lower_bound. */ |
| 292 | |
| 293 | static inline int |
| 294 | arm_compare_mapping_symbols (const struct arm_mapping_symbol *lhs, |
| 295 | const struct arm_mapping_symbol *rhs) |
| 296 | { |
| 297 | return lhs->value < rhs->value; |
| 298 | } |
| 299 | |
| 300 | /* Search for the mapping symbol covering MEMADDR. If one is found, |
| 301 | return its type. Otherwise, return 0. If START is non-NULL, |
| 302 | set *START to the location of the mapping symbol. */ |
| 303 | |
| 304 | static char |
| 305 | arm_find_mapping_symbol (CORE_ADDR memaddr, CORE_ADDR *start) |
| 306 | { |
| 307 | struct obj_section *sec; |
| 308 | |
| 309 | /* If there are mapping symbols, consult them. */ |
| 310 | sec = find_pc_section (memaddr); |
| 311 | if (sec != NULL) |
| 312 | { |
| 313 | struct arm_per_objfile *data; |
| 314 | VEC(arm_mapping_symbol_s) *map; |
| 315 | struct arm_mapping_symbol map_key = { memaddr - obj_section_addr (sec), |
| 316 | 0 }; |
| 317 | unsigned int idx; |
| 318 | |
| 319 | data = objfile_data (sec->objfile, arm_objfile_data_key); |
| 320 | if (data != NULL) |
| 321 | { |
| 322 | map = data->section_maps[sec->the_bfd_section->index]; |
| 323 | if (!VEC_empty (arm_mapping_symbol_s, map)) |
| 324 | { |
| 325 | struct arm_mapping_symbol *map_sym; |
| 326 | |
| 327 | idx = VEC_lower_bound (arm_mapping_symbol_s, map, &map_key, |
| 328 | arm_compare_mapping_symbols); |
| 329 | |
| 330 | /* VEC_lower_bound finds the earliest ordered insertion |
| 331 | point. If the following symbol starts at this exact |
| 332 | address, we use that; otherwise, the preceding |
| 333 | mapping symbol covers this address. */ |
| 334 | if (idx < VEC_length (arm_mapping_symbol_s, map)) |
| 335 | { |
| 336 | map_sym = VEC_index (arm_mapping_symbol_s, map, idx); |
| 337 | if (map_sym->value == map_key.value) |
| 338 | { |
| 339 | if (start) |
| 340 | *start = map_sym->value + obj_section_addr (sec); |
| 341 | return map_sym->type; |
| 342 | } |
| 343 | } |
| 344 | |
| 345 | if (idx > 0) |
| 346 | { |
| 347 | map_sym = VEC_index (arm_mapping_symbol_s, map, idx - 1); |
| 348 | if (start) |
| 349 | *start = map_sym->value + obj_section_addr (sec); |
| 350 | return map_sym->type; |
| 351 | } |
| 352 | } |
| 353 | } |
| 354 | } |
| 355 | |
| 356 | return 0; |
| 357 | } |
| 358 | |
| 359 | static CORE_ADDR arm_get_next_pc_raw (struct frame_info *frame, |
| 360 | CORE_ADDR pc, int insert_bkpt); |
| 361 | |
| 362 | /* Determine if the program counter specified in MEMADDR is in a Thumb |
| 363 | function. This function should be called for addresses unrelated to |
| 364 | any executing frame; otherwise, prefer arm_frame_is_thumb. */ |
| 365 | |
| 366 | int |
| 367 | arm_pc_is_thumb (struct gdbarch *gdbarch, CORE_ADDR memaddr) |
| 368 | { |
| 369 | struct obj_section *sec; |
| 370 | struct minimal_symbol *sym; |
| 371 | char type; |
| 372 | struct displaced_step_closure* dsc |
| 373 | = get_displaced_step_closure_by_addr(memaddr); |
| 374 | |
| 375 | /* If checking the mode of displaced instruction in copy area, the mode |
| 376 | should be determined by instruction on the original address. */ |
| 377 | if (dsc) |
| 378 | { |
| 379 | if (debug_displaced) |
| 380 | fprintf_unfiltered (gdb_stdlog, |
| 381 | "displaced: check mode of %.8lx instead of %.8lx\n", |
| 382 | (unsigned long) dsc->insn_addr, |
| 383 | (unsigned long) memaddr); |
| 384 | memaddr = dsc->insn_addr; |
| 385 | } |
| 386 | |
| 387 | /* If bit 0 of the address is set, assume this is a Thumb address. */ |
| 388 | if (IS_THUMB_ADDR (memaddr)) |
| 389 | return 1; |
| 390 | |
| 391 | /* If the user wants to override the symbol table, let him. */ |
| 392 | if (strcmp (arm_force_mode_string, "arm") == 0) |
| 393 | return 0; |
| 394 | if (strcmp (arm_force_mode_string, "thumb") == 0) |
| 395 | return 1; |
| 396 | |
| 397 | /* ARM v6-M and v7-M are always in Thumb mode. */ |
| 398 | if (gdbarch_tdep (gdbarch)->is_m) |
| 399 | return 1; |
| 400 | |
| 401 | /* If there are mapping symbols, consult them. */ |
| 402 | type = arm_find_mapping_symbol (memaddr, NULL); |
| 403 | if (type) |
| 404 | return type == 't'; |
| 405 | |
| 406 | /* Thumb functions have a "special" bit set in minimal symbols. */ |
| 407 | sym = lookup_minimal_symbol_by_pc (memaddr); |
| 408 | if (sym) |
| 409 | return (MSYMBOL_IS_SPECIAL (sym)); |
| 410 | |
| 411 | /* If the user wants to override the fallback mode, let them. */ |
| 412 | if (strcmp (arm_fallback_mode_string, "arm") == 0) |
| 413 | return 0; |
| 414 | if (strcmp (arm_fallback_mode_string, "thumb") == 0) |
| 415 | return 1; |
| 416 | |
| 417 | /* If we couldn't find any symbol, but we're talking to a running |
| 418 | target, then trust the current value of $cpsr. This lets |
| 419 | "display/i $pc" always show the correct mode (though if there is |
| 420 | a symbol table we will not reach here, so it still may not be |
| 421 | displayed in the mode it will be executed). |
| 422 | |
| 423 | As a further heuristic if we detect that we are doing a single-step we |
| 424 | see what state executing the current instruction ends up with us being |
| 425 | in. */ |
| 426 | if (target_has_registers) |
| 427 | { |
| 428 | struct frame_info *current_frame = get_current_frame (); |
| 429 | CORE_ADDR current_pc = get_frame_pc (current_frame); |
| 430 | int is_thumb = arm_frame_is_thumb (current_frame); |
| 431 | CORE_ADDR next_pc; |
| 432 | if (memaddr == current_pc) |
| 433 | return is_thumb; |
| 434 | else |
| 435 | { |
| 436 | struct gdbarch *gdbarch = get_frame_arch (current_frame); |
| 437 | next_pc = arm_get_next_pc_raw (current_frame, current_pc, FALSE); |
| 438 | if (memaddr == gdbarch_addr_bits_remove (gdbarch, next_pc)) |
| 439 | return IS_THUMB_ADDR (next_pc); |
| 440 | else |
| 441 | return is_thumb; |
| 442 | } |
| 443 | } |
| 444 | |
| 445 | /* Otherwise we're out of luck; we assume ARM. */ |
| 446 | return 0; |
| 447 | } |
| 448 | |
| 449 | /* Remove useless bits from addresses in a running program. */ |
| 450 | static CORE_ADDR |
| 451 | arm_addr_bits_remove (struct gdbarch *gdbarch, CORE_ADDR val) |
| 452 | { |
| 453 | if (arm_apcs_32) |
| 454 | return UNMAKE_THUMB_ADDR (val); |
| 455 | else |
| 456 | return (val & 0x03fffffc); |
| 457 | } |
| 458 | |
| 459 | /* When reading symbols, we need to zap the low bit of the address, |
| 460 | which may be set to 1 for Thumb functions. */ |
| 461 | static CORE_ADDR |
| 462 | arm_smash_text_address (struct gdbarch *gdbarch, CORE_ADDR val) |
| 463 | { |
| 464 | return val & ~1; |
| 465 | } |
| 466 | |
| 467 | /* Return 1 if PC is the start of a compiler helper function which |
| 468 | can be safely ignored during prologue skipping. IS_THUMB is true |
| 469 | if the function is known to be a Thumb function due to the way it |
| 470 | is being called. */ |
| 471 | static int |
| 472 | skip_prologue_function (struct gdbarch *gdbarch, CORE_ADDR pc, int is_thumb) |
| 473 | { |
| 474 | enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch); |
| 475 | struct minimal_symbol *msym; |
| 476 | |
| 477 | msym = lookup_minimal_symbol_by_pc (pc); |
| 478 | if (msym != NULL |
| 479 | && SYMBOL_VALUE_ADDRESS (msym) == pc |
| 480 | && SYMBOL_LINKAGE_NAME (msym) != NULL) |
| 481 | { |
| 482 | const char *name = SYMBOL_LINKAGE_NAME (msym); |
| 483 | |
| 484 | /* The GNU linker's Thumb call stub to foo is named |
| 485 | __foo_from_thumb. */ |
| 486 | if (strstr (name, "_from_thumb") != NULL) |
| 487 | name += 2; |
| 488 | |
| 489 | /* On soft-float targets, __truncdfsf2 is called to convert promoted |
| 490 | arguments to their argument types in non-prototyped |
| 491 | functions. */ |
| 492 | if (strncmp (name, "__truncdfsf2", strlen ("__truncdfsf2")) == 0) |
| 493 | return 1; |
| 494 | if (strncmp (name, "__aeabi_d2f", strlen ("__aeabi_d2f")) == 0) |
| 495 | return 1; |
| 496 | |
| 497 | /* Internal functions related to thread-local storage. */ |
| 498 | if (strncmp (name, "__tls_get_addr", strlen ("__tls_get_addr")) == 0) |
| 499 | return 1; |
| 500 | if (strncmp (name, "__aeabi_read_tp", strlen ("__aeabi_read_tp")) == 0) |
| 501 | return 1; |
| 502 | } |
| 503 | else |
| 504 | { |
| 505 | /* If we run against a stripped glibc, we may be unable to identify |
| 506 | special functions by name. Check for one important case, |
| 507 | __aeabi_read_tp, by comparing the *code* against the default |
| 508 | implementation (this is hand-written ARM assembler in glibc). */ |
| 509 | |
| 510 | if (!is_thumb |
| 511 | && read_memory_unsigned_integer (pc, 4, byte_order_for_code) |
| 512 | == 0xe3e00a0f /* mov r0, #0xffff0fff */ |
| 513 | && read_memory_unsigned_integer (pc + 4, 4, byte_order_for_code) |
| 514 | == 0xe240f01f) /* sub pc, r0, #31 */ |
| 515 | return 1; |
| 516 | } |
| 517 | |
| 518 | return 0; |
| 519 | } |
| 520 | |
| 521 | /* Support routines for instruction parsing. */ |
| 522 | #define submask(x) ((1L << ((x) + 1)) - 1) |
| 523 | #define bit(obj,st) (((obj) >> (st)) & 1) |
| 524 | #define bits(obj,st,fn) (((obj) >> (st)) & submask ((fn) - (st))) |
| 525 | #define sbits(obj,st,fn) \ |
| 526 | ((long) (bits(obj,st,fn) | ((long) bit(obj,fn) * ~ submask (fn - st)))) |
| 527 | #define BranchDest(addr,instr) \ |
| 528 | ((CORE_ADDR) (((long) (addr)) + 8 + (sbits (instr, 0, 23) << 2))) |
| 529 | |
| 530 | /* Extract the immediate from instruction movw/movt of encoding T. INSN1 is |
| 531 | the first 16-bit of instruction, and INSN2 is the second 16-bit of |
| 532 | instruction. */ |
| 533 | #define EXTRACT_MOVW_MOVT_IMM_T(insn1, insn2) \ |
| 534 | ((bits ((insn1), 0, 3) << 12) \ |
| 535 | | (bits ((insn1), 10, 10) << 11) \ |
| 536 | | (bits ((insn2), 12, 14) << 8) \ |
| 537 | | bits ((insn2), 0, 7)) |
| 538 | |
| 539 | /* Extract the immediate from instruction movw/movt of encoding A. INSN is |
| 540 | the 32-bit instruction. */ |
| 541 | #define EXTRACT_MOVW_MOVT_IMM_A(insn) \ |
| 542 | ((bits ((insn), 16, 19) << 12) \ |
| 543 | | bits ((insn), 0, 11)) |
| 544 | |
| 545 | /* Decode immediate value; implements ThumbExpandImmediate pseudo-op. */ |
| 546 | |
| 547 | static unsigned int |
| 548 | thumb_expand_immediate (unsigned int imm) |
| 549 | { |
| 550 | unsigned int count = imm >> 7; |
| 551 | |
| 552 | if (count < 8) |
| 553 | switch (count / 2) |
| 554 | { |
| 555 | case 0: |
| 556 | return imm & 0xff; |
| 557 | case 1: |
| 558 | return (imm & 0xff) | ((imm & 0xff) << 16); |
| 559 | case 2: |
| 560 | return ((imm & 0xff) << 8) | ((imm & 0xff) << 24); |
| 561 | case 3: |
| 562 | return (imm & 0xff) | ((imm & 0xff) << 8) |
| 563 | | ((imm & 0xff) << 16) | ((imm & 0xff) << 24); |
| 564 | } |
| 565 | |
| 566 | return (0x80 | (imm & 0x7f)) << (32 - count); |
| 567 | } |
| 568 | |
| 569 | /* Return 1 if the 16-bit Thumb instruction INST might change |
| 570 | control flow, 0 otherwise. */ |
| 571 | |
| 572 | static int |
| 573 | thumb_instruction_changes_pc (unsigned short inst) |
| 574 | { |
| 575 | if ((inst & 0xff00) == 0xbd00) /* pop {rlist, pc} */ |
| 576 | return 1; |
| 577 | |
| 578 | if ((inst & 0xf000) == 0xd000) /* conditional branch */ |
| 579 | return 1; |
| 580 | |
| 581 | if ((inst & 0xf800) == 0xe000) /* unconditional branch */ |
| 582 | return 1; |
| 583 | |
| 584 | if ((inst & 0xff00) == 0x4700) /* bx REG, blx REG */ |
| 585 | return 1; |
| 586 | |
| 587 | if ((inst & 0xff87) == 0x4687) /* mov pc, REG */ |
| 588 | return 1; |
| 589 | |
| 590 | if ((inst & 0xf500) == 0xb100) /* CBNZ or CBZ. */ |
| 591 | return 1; |
| 592 | |
| 593 | return 0; |
| 594 | } |
| 595 | |
| 596 | /* Return 1 if the 32-bit Thumb instruction in INST1 and INST2 |
| 597 | might change control flow, 0 otherwise. */ |
| 598 | |
| 599 | static int |
| 600 | thumb2_instruction_changes_pc (unsigned short inst1, unsigned short inst2) |
| 601 | { |
| 602 | if ((inst1 & 0xf800) == 0xf000 && (inst2 & 0x8000) == 0x8000) |
| 603 | { |
| 604 | /* Branches and miscellaneous control instructions. */ |
| 605 | |
| 606 | if ((inst2 & 0x1000) != 0 || (inst2 & 0xd001) == 0xc000) |
| 607 | { |
| 608 | /* B, BL, BLX. */ |
| 609 | return 1; |
| 610 | } |
| 611 | else if (inst1 == 0xf3de && (inst2 & 0xff00) == 0x3f00) |
| 612 | { |
| 613 | /* SUBS PC, LR, #imm8. */ |
| 614 | return 1; |
| 615 | } |
| 616 | else if ((inst2 & 0xd000) == 0x8000 && (inst1 & 0x0380) != 0x0380) |
| 617 | { |
| 618 | /* Conditional branch. */ |
| 619 | return 1; |
| 620 | } |
| 621 | |
| 622 | return 0; |
| 623 | } |
| 624 | |
| 625 | if ((inst1 & 0xfe50) == 0xe810) |
| 626 | { |
| 627 | /* Load multiple or RFE. */ |
| 628 | |
| 629 | if (bit (inst1, 7) && !bit (inst1, 8)) |
| 630 | { |
| 631 | /* LDMIA or POP */ |
| 632 | if (bit (inst2, 15)) |
| 633 | return 1; |
| 634 | } |
| 635 | else if (!bit (inst1, 7) && bit (inst1, 8)) |
| 636 | { |
| 637 | /* LDMDB */ |
| 638 | if (bit (inst2, 15)) |
| 639 | return 1; |
| 640 | } |
| 641 | else if (bit (inst1, 7) && bit (inst1, 8)) |
| 642 | { |
| 643 | /* RFEIA */ |
| 644 | return 1; |
| 645 | } |
| 646 | else if (!bit (inst1, 7) && !bit (inst1, 8)) |
| 647 | { |
| 648 | /* RFEDB */ |
| 649 | return 1; |
| 650 | } |
| 651 | |
| 652 | return 0; |
| 653 | } |
| 654 | |
| 655 | if ((inst1 & 0xffef) == 0xea4f && (inst2 & 0xfff0) == 0x0f00) |
| 656 | { |
| 657 | /* MOV PC or MOVS PC. */ |
| 658 | return 1; |
| 659 | } |
| 660 | |
| 661 | if ((inst1 & 0xff70) == 0xf850 && (inst2 & 0xf000) == 0xf000) |
| 662 | { |
| 663 | /* LDR PC. */ |
| 664 | if (bits (inst1, 0, 3) == 15) |
| 665 | return 1; |
| 666 | if (bit (inst1, 7)) |
| 667 | return 1; |
| 668 | if (bit (inst2, 11)) |
| 669 | return 1; |
| 670 | if ((inst2 & 0x0fc0) == 0x0000) |
| 671 | return 1; |
| 672 | |
| 673 | return 0; |
| 674 | } |
| 675 | |
| 676 | if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf000) |
| 677 | { |
| 678 | /* TBB. */ |
| 679 | return 1; |
| 680 | } |
| 681 | |
| 682 | if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf010) |
| 683 | { |
| 684 | /* TBH. */ |
| 685 | return 1; |
| 686 | } |
| 687 | |
| 688 | return 0; |
| 689 | } |
| 690 | |
| 691 | /* Analyze a Thumb prologue, looking for a recognizable stack frame |
| 692 | and frame pointer. Scan until we encounter a store that could |
| 693 | clobber the stack frame unexpectedly, or an unknown instruction. |
| 694 | Return the last address which is definitely safe to skip for an |
| 695 | initial breakpoint. */ |
| 696 | |
| 697 | static CORE_ADDR |
| 698 | thumb_analyze_prologue (struct gdbarch *gdbarch, |
| 699 | CORE_ADDR start, CORE_ADDR limit, |
| 700 | struct arm_prologue_cache *cache) |
| 701 | { |
| 702 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 703 | enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch); |
| 704 | int i; |
| 705 | pv_t regs[16]; |
| 706 | struct pv_area *stack; |
| 707 | struct cleanup *back_to; |
| 708 | CORE_ADDR offset; |
| 709 | CORE_ADDR unrecognized_pc = 0; |
| 710 | |
| 711 | for (i = 0; i < 16; i++) |
| 712 | regs[i] = pv_register (i, 0); |
| 713 | stack = make_pv_area (ARM_SP_REGNUM, gdbarch_addr_bit (gdbarch)); |
| 714 | back_to = make_cleanup_free_pv_area (stack); |
| 715 | |
| 716 | while (start < limit) |
| 717 | { |
| 718 | unsigned short insn; |
| 719 | |
| 720 | insn = read_memory_unsigned_integer (start, 2, byte_order_for_code); |
| 721 | |
| 722 | if ((insn & 0xfe00) == 0xb400) /* push { rlist } */ |
| 723 | { |
| 724 | int regno; |
| 725 | int mask; |
| 726 | |
| 727 | if (pv_area_store_would_trash (stack, regs[ARM_SP_REGNUM])) |
| 728 | break; |
| 729 | |
| 730 | /* Bits 0-7 contain a mask for registers R0-R7. Bit 8 says |
| 731 | whether to save LR (R14). */ |
| 732 | mask = (insn & 0xff) | ((insn & 0x100) << 6); |
| 733 | |
| 734 | /* Calculate offsets of saved R0-R7 and LR. */ |
| 735 | for (regno = ARM_LR_REGNUM; regno >= 0; regno--) |
| 736 | if (mask & (1 << regno)) |
| 737 | { |
| 738 | regs[ARM_SP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM], |
| 739 | -4); |
| 740 | pv_area_store (stack, regs[ARM_SP_REGNUM], 4, regs[regno]); |
| 741 | } |
| 742 | } |
| 743 | else if ((insn & 0xff00) == 0xb000) /* add sp, #simm OR |
| 744 | sub sp, #simm */ |
| 745 | { |
| 746 | offset = (insn & 0x7f) << 2; /* get scaled offset */ |
| 747 | if (insn & 0x80) /* Check for SUB. */ |
| 748 | regs[ARM_SP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM], |
| 749 | -offset); |
| 750 | else |
| 751 | regs[ARM_SP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM], |
| 752 | offset); |
| 753 | } |
| 754 | else if ((insn & 0xf800) == 0xa800) /* add Rd, sp, #imm */ |
| 755 | regs[bits (insn, 8, 10)] = pv_add_constant (regs[ARM_SP_REGNUM], |
| 756 | (insn & 0xff) << 2); |
| 757 | else if ((insn & 0xfe00) == 0x1c00 /* add Rd, Rn, #imm */ |
| 758 | && pv_is_register (regs[bits (insn, 3, 5)], ARM_SP_REGNUM)) |
| 759 | regs[bits (insn, 0, 2)] = pv_add_constant (regs[bits (insn, 3, 5)], |
| 760 | bits (insn, 6, 8)); |
| 761 | else if ((insn & 0xf800) == 0x3000 /* add Rd, #imm */ |
| 762 | && pv_is_register (regs[bits (insn, 8, 10)], ARM_SP_REGNUM)) |
| 763 | regs[bits (insn, 8, 10)] = pv_add_constant (regs[bits (insn, 8, 10)], |
| 764 | bits (insn, 0, 7)); |
| 765 | else if ((insn & 0xfe00) == 0x1800 /* add Rd, Rn, Rm */ |
| 766 | && pv_is_register (regs[bits (insn, 6, 8)], ARM_SP_REGNUM) |
| 767 | && pv_is_constant (regs[bits (insn, 3, 5)])) |
| 768 | regs[bits (insn, 0, 2)] = pv_add (regs[bits (insn, 3, 5)], |
| 769 | regs[bits (insn, 6, 8)]); |
| 770 | else if ((insn & 0xff00) == 0x4400 /* add Rd, Rm */ |
| 771 | && pv_is_constant (regs[bits (insn, 3, 6)])) |
| 772 | { |
| 773 | int rd = (bit (insn, 7) << 3) + bits (insn, 0, 2); |
| 774 | int rm = bits (insn, 3, 6); |
| 775 | regs[rd] = pv_add (regs[rd], regs[rm]); |
| 776 | } |
| 777 | else if ((insn & 0xff00) == 0x4600) /* mov hi, lo or mov lo, hi */ |
| 778 | { |
| 779 | int dst_reg = (insn & 0x7) + ((insn & 0x80) >> 4); |
| 780 | int src_reg = (insn & 0x78) >> 3; |
| 781 | regs[dst_reg] = regs[src_reg]; |
| 782 | } |
| 783 | else if ((insn & 0xf800) == 0x9000) /* str rd, [sp, #off] */ |
| 784 | { |
| 785 | /* Handle stores to the stack. Normally pushes are used, |
| 786 | but with GCC -mtpcs-frame, there may be other stores |
| 787 | in the prologue to create the frame. */ |
| 788 | int regno = (insn >> 8) & 0x7; |
| 789 | pv_t addr; |
| 790 | |
| 791 | offset = (insn & 0xff) << 2; |
| 792 | addr = pv_add_constant (regs[ARM_SP_REGNUM], offset); |
| 793 | |
| 794 | if (pv_area_store_would_trash (stack, addr)) |
| 795 | break; |
| 796 | |
| 797 | pv_area_store (stack, addr, 4, regs[regno]); |
| 798 | } |
| 799 | else if ((insn & 0xf800) == 0x6000) /* str rd, [rn, #off] */ |
| 800 | { |
| 801 | int rd = bits (insn, 0, 2); |
| 802 | int rn = bits (insn, 3, 5); |
| 803 | pv_t addr; |
| 804 | |
| 805 | offset = bits (insn, 6, 10) << 2; |
| 806 | addr = pv_add_constant (regs[rn], offset); |
| 807 | |
| 808 | if (pv_area_store_would_trash (stack, addr)) |
| 809 | break; |
| 810 | |
| 811 | pv_area_store (stack, addr, 4, regs[rd]); |
| 812 | } |
| 813 | else if (((insn & 0xf800) == 0x7000 /* strb Rd, [Rn, #off] */ |
| 814 | || (insn & 0xf800) == 0x8000) /* strh Rd, [Rn, #off] */ |
| 815 | && pv_is_register (regs[bits (insn, 3, 5)], ARM_SP_REGNUM)) |
| 816 | /* Ignore stores of argument registers to the stack. */ |
| 817 | ; |
| 818 | else if ((insn & 0xf800) == 0xc800 /* ldmia Rn!, { registers } */ |
| 819 | && pv_is_register (regs[bits (insn, 8, 10)], ARM_SP_REGNUM)) |
| 820 | /* Ignore block loads from the stack, potentially copying |
| 821 | parameters from memory. */ |
| 822 | ; |
| 823 | else if ((insn & 0xf800) == 0x9800 /* ldr Rd, [Rn, #immed] */ |
| 824 | || ((insn & 0xf800) == 0x6800 /* ldr Rd, [sp, #immed] */ |
| 825 | && pv_is_register (regs[bits (insn, 3, 5)], ARM_SP_REGNUM))) |
| 826 | /* Similarly ignore single loads from the stack. */ |
| 827 | ; |
| 828 | else if ((insn & 0xffc0) == 0x0000 /* lsls Rd, Rm, #0 */ |
| 829 | || (insn & 0xffc0) == 0x1c00) /* add Rd, Rn, #0 */ |
| 830 | /* Skip register copies, i.e. saves to another register |
| 831 | instead of the stack. */ |
| 832 | ; |
| 833 | else if ((insn & 0xf800) == 0x2000) /* movs Rd, #imm */ |
| 834 | /* Recognize constant loads; even with small stacks these are necessary |
| 835 | on Thumb. */ |
| 836 | regs[bits (insn, 8, 10)] = pv_constant (bits (insn, 0, 7)); |
| 837 | else if ((insn & 0xf800) == 0x4800) /* ldr Rd, [pc, #imm] */ |
| 838 | { |
| 839 | /* Constant pool loads, for the same reason. */ |
| 840 | unsigned int constant; |
| 841 | CORE_ADDR loc; |
| 842 | |
| 843 | loc = start + 4 + bits (insn, 0, 7) * 4; |
| 844 | constant = read_memory_unsigned_integer (loc, 4, byte_order); |
| 845 | regs[bits (insn, 8, 10)] = pv_constant (constant); |
| 846 | } |
| 847 | else if ((insn & 0xe000) == 0xe000) |
| 848 | { |
| 849 | unsigned short inst2; |
| 850 | |
| 851 | inst2 = read_memory_unsigned_integer (start + 2, 2, |
| 852 | byte_order_for_code); |
| 853 | |
| 854 | if ((insn & 0xf800) == 0xf000 && (inst2 & 0xe800) == 0xe800) |
| 855 | { |
| 856 | /* BL, BLX. Allow some special function calls when |
| 857 | skipping the prologue; GCC generates these before |
| 858 | storing arguments to the stack. */ |
| 859 | CORE_ADDR nextpc; |
| 860 | int j1, j2, imm1, imm2; |
| 861 | |
| 862 | imm1 = sbits (insn, 0, 10); |
| 863 | imm2 = bits (inst2, 0, 10); |
| 864 | j1 = bit (inst2, 13); |
| 865 | j2 = bit (inst2, 11); |
| 866 | |
| 867 | offset = ((imm1 << 12) + (imm2 << 1)); |
| 868 | offset ^= ((!j2) << 22) | ((!j1) << 23); |
| 869 | |
| 870 | nextpc = start + 4 + offset; |
| 871 | /* For BLX make sure to clear the low bits. */ |
| 872 | if (bit (inst2, 12) == 0) |
| 873 | nextpc = nextpc & 0xfffffffc; |
| 874 | |
| 875 | if (!skip_prologue_function (gdbarch, nextpc, |
| 876 | bit (inst2, 12) != 0)) |
| 877 | break; |
| 878 | } |
| 879 | |
| 880 | else if ((insn & 0xffd0) == 0xe900 /* stmdb Rn{!}, |
| 881 | { registers } */ |
| 882 | && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM)) |
| 883 | { |
| 884 | pv_t addr = regs[bits (insn, 0, 3)]; |
| 885 | int regno; |
| 886 | |
| 887 | if (pv_area_store_would_trash (stack, addr)) |
| 888 | break; |
| 889 | |
| 890 | /* Calculate offsets of saved registers. */ |
| 891 | for (regno = ARM_LR_REGNUM; regno >= 0; regno--) |
| 892 | if (inst2 & (1 << regno)) |
| 893 | { |
| 894 | addr = pv_add_constant (addr, -4); |
| 895 | pv_area_store (stack, addr, 4, regs[regno]); |
| 896 | } |
| 897 | |
| 898 | if (insn & 0x0020) |
| 899 | regs[bits (insn, 0, 3)] = addr; |
| 900 | } |
| 901 | |
| 902 | else if ((insn & 0xff50) == 0xe940 /* strd Rt, Rt2, |
| 903 | [Rn, #+/-imm]{!} */ |
| 904 | && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM)) |
| 905 | { |
| 906 | int regno1 = bits (inst2, 12, 15); |
| 907 | int regno2 = bits (inst2, 8, 11); |
| 908 | pv_t addr = regs[bits (insn, 0, 3)]; |
| 909 | |
| 910 | offset = inst2 & 0xff; |
| 911 | if (insn & 0x0080) |
| 912 | addr = pv_add_constant (addr, offset); |
| 913 | else |
| 914 | addr = pv_add_constant (addr, -offset); |
| 915 | |
| 916 | if (pv_area_store_would_trash (stack, addr)) |
| 917 | break; |
| 918 | |
| 919 | pv_area_store (stack, addr, 4, regs[regno1]); |
| 920 | pv_area_store (stack, pv_add_constant (addr, 4), |
| 921 | 4, regs[regno2]); |
| 922 | |
| 923 | if (insn & 0x0020) |
| 924 | regs[bits (insn, 0, 3)] = addr; |
| 925 | } |
| 926 | |
| 927 | else if ((insn & 0xfff0) == 0xf8c0 /* str Rt,[Rn,+/-#imm]{!} */ |
| 928 | && (inst2 & 0x0c00) == 0x0c00 |
| 929 | && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM)) |
| 930 | { |
| 931 | int regno = bits (inst2, 12, 15); |
| 932 | pv_t addr = regs[bits (insn, 0, 3)]; |
| 933 | |
| 934 | offset = inst2 & 0xff; |
| 935 | if (inst2 & 0x0200) |
| 936 | addr = pv_add_constant (addr, offset); |
| 937 | else |
| 938 | addr = pv_add_constant (addr, -offset); |
| 939 | |
| 940 | if (pv_area_store_would_trash (stack, addr)) |
| 941 | break; |
| 942 | |
| 943 | pv_area_store (stack, addr, 4, regs[regno]); |
| 944 | |
| 945 | if (inst2 & 0x0100) |
| 946 | regs[bits (insn, 0, 3)] = addr; |
| 947 | } |
| 948 | |
| 949 | else if ((insn & 0xfff0) == 0xf8c0 /* str.w Rt,[Rn,#imm] */ |
| 950 | && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM)) |
| 951 | { |
| 952 | int regno = bits (inst2, 12, 15); |
| 953 | pv_t addr; |
| 954 | |
| 955 | offset = inst2 & 0xfff; |
| 956 | addr = pv_add_constant (regs[bits (insn, 0, 3)], offset); |
| 957 | |
| 958 | if (pv_area_store_would_trash (stack, addr)) |
| 959 | break; |
| 960 | |
| 961 | pv_area_store (stack, addr, 4, regs[regno]); |
| 962 | } |
| 963 | |
| 964 | else if ((insn & 0xffd0) == 0xf880 /* str{bh}.w Rt,[Rn,#imm] */ |
| 965 | && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM)) |
| 966 | /* Ignore stores of argument registers to the stack. */ |
| 967 | ; |
| 968 | |
| 969 | else if ((insn & 0xffd0) == 0xf800 /* str{bh} Rt,[Rn,#+/-imm] */ |
| 970 | && (inst2 & 0x0d00) == 0x0c00 |
| 971 | && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM)) |
| 972 | /* Ignore stores of argument registers to the stack. */ |
| 973 | ; |
| 974 | |
| 975 | else if ((insn & 0xffd0) == 0xe890 /* ldmia Rn[!], |
| 976 | { registers } */ |
| 977 | && (inst2 & 0x8000) == 0x0000 |
| 978 | && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM)) |
| 979 | /* Ignore block loads from the stack, potentially copying |
| 980 | parameters from memory. */ |
| 981 | ; |
| 982 | |
| 983 | else if ((insn & 0xffb0) == 0xe950 /* ldrd Rt, Rt2, |
| 984 | [Rn, #+/-imm] */ |
| 985 | && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM)) |
| 986 | /* Similarly ignore dual loads from the stack. */ |
| 987 | ; |
| 988 | |
| 989 | else if ((insn & 0xfff0) == 0xf850 /* ldr Rt,[Rn,#+/-imm] */ |
| 990 | && (inst2 & 0x0d00) == 0x0c00 |
| 991 | && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM)) |
| 992 | /* Similarly ignore single loads from the stack. */ |
| 993 | ; |
| 994 | |
| 995 | else if ((insn & 0xfff0) == 0xf8d0 /* ldr.w Rt,[Rn,#imm] */ |
| 996 | && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM)) |
| 997 | /* Similarly ignore single loads from the stack. */ |
| 998 | ; |
| 999 | |
| 1000 | else if ((insn & 0xfbf0) == 0xf100 /* add.w Rd, Rn, #imm */ |
| 1001 | && (inst2 & 0x8000) == 0x0000) |
| 1002 | { |
| 1003 | unsigned int imm = ((bits (insn, 10, 10) << 11) |
| 1004 | | (bits (inst2, 12, 14) << 8) |
| 1005 | | bits (inst2, 0, 7)); |
| 1006 | |
| 1007 | regs[bits (inst2, 8, 11)] |
| 1008 | = pv_add_constant (regs[bits (insn, 0, 3)], |
| 1009 | thumb_expand_immediate (imm)); |
| 1010 | } |
| 1011 | |
| 1012 | else if ((insn & 0xfbf0) == 0xf200 /* addw Rd, Rn, #imm */ |
| 1013 | && (inst2 & 0x8000) == 0x0000) |
| 1014 | { |
| 1015 | unsigned int imm = ((bits (insn, 10, 10) << 11) |
| 1016 | | (bits (inst2, 12, 14) << 8) |
| 1017 | | bits (inst2, 0, 7)); |
| 1018 | |
| 1019 | regs[bits (inst2, 8, 11)] |
| 1020 | = pv_add_constant (regs[bits (insn, 0, 3)], imm); |
| 1021 | } |
| 1022 | |
| 1023 | else if ((insn & 0xfbf0) == 0xf1a0 /* sub.w Rd, Rn, #imm */ |
| 1024 | && (inst2 & 0x8000) == 0x0000) |
| 1025 | { |
| 1026 | unsigned int imm = ((bits (insn, 10, 10) << 11) |
| 1027 | | (bits (inst2, 12, 14) << 8) |
| 1028 | | bits (inst2, 0, 7)); |
| 1029 | |
| 1030 | regs[bits (inst2, 8, 11)] |
| 1031 | = pv_add_constant (regs[bits (insn, 0, 3)], |
| 1032 | - (CORE_ADDR) thumb_expand_immediate (imm)); |
| 1033 | } |
| 1034 | |
| 1035 | else if ((insn & 0xfbf0) == 0xf2a0 /* subw Rd, Rn, #imm */ |
| 1036 | && (inst2 & 0x8000) == 0x0000) |
| 1037 | { |
| 1038 | unsigned int imm = ((bits (insn, 10, 10) << 11) |
| 1039 | | (bits (inst2, 12, 14) << 8) |
| 1040 | | bits (inst2, 0, 7)); |
| 1041 | |
| 1042 | regs[bits (inst2, 8, 11)] |
| 1043 | = pv_add_constant (regs[bits (insn, 0, 3)], - (CORE_ADDR) imm); |
| 1044 | } |
| 1045 | |
| 1046 | else if ((insn & 0xfbff) == 0xf04f) /* mov.w Rd, #const */ |
| 1047 | { |
| 1048 | unsigned int imm = ((bits (insn, 10, 10) << 11) |
| 1049 | | (bits (inst2, 12, 14) << 8) |
| 1050 | | bits (inst2, 0, 7)); |
| 1051 | |
| 1052 | regs[bits (inst2, 8, 11)] |
| 1053 | = pv_constant (thumb_expand_immediate (imm)); |
| 1054 | } |
| 1055 | |
| 1056 | else if ((insn & 0xfbf0) == 0xf240) /* movw Rd, #const */ |
| 1057 | { |
| 1058 | unsigned int imm |
| 1059 | = EXTRACT_MOVW_MOVT_IMM_T (insn, inst2); |
| 1060 | |
| 1061 | regs[bits (inst2, 8, 11)] = pv_constant (imm); |
| 1062 | } |
| 1063 | |
| 1064 | else if (insn == 0xea5f /* mov.w Rd,Rm */ |
| 1065 | && (inst2 & 0xf0f0) == 0) |
| 1066 | { |
| 1067 | int dst_reg = (inst2 & 0x0f00) >> 8; |
| 1068 | int src_reg = inst2 & 0xf; |
| 1069 | regs[dst_reg] = regs[src_reg]; |
| 1070 | } |
| 1071 | |
| 1072 | else if ((insn & 0xff7f) == 0xf85f) /* ldr.w Rt,<label> */ |
| 1073 | { |
| 1074 | /* Constant pool loads. */ |
| 1075 | unsigned int constant; |
| 1076 | CORE_ADDR loc; |
| 1077 | |
| 1078 | offset = bits (insn, 0, 11); |
| 1079 | if (insn & 0x0080) |
| 1080 | loc = start + 4 + offset; |
| 1081 | else |
| 1082 | loc = start + 4 - offset; |
| 1083 | |
| 1084 | constant = read_memory_unsigned_integer (loc, 4, byte_order); |
| 1085 | regs[bits (inst2, 12, 15)] = pv_constant (constant); |
| 1086 | } |
| 1087 | |
| 1088 | else if ((insn & 0xff7f) == 0xe95f) /* ldrd Rt,Rt2,<label> */ |
| 1089 | { |
| 1090 | /* Constant pool loads. */ |
| 1091 | unsigned int constant; |
| 1092 | CORE_ADDR loc; |
| 1093 | |
| 1094 | offset = bits (insn, 0, 7) << 2; |
| 1095 | if (insn & 0x0080) |
| 1096 | loc = start + 4 + offset; |
| 1097 | else |
| 1098 | loc = start + 4 - offset; |
| 1099 | |
| 1100 | constant = read_memory_unsigned_integer (loc, 4, byte_order); |
| 1101 | regs[bits (inst2, 12, 15)] = pv_constant (constant); |
| 1102 | |
| 1103 | constant = read_memory_unsigned_integer (loc + 4, 4, byte_order); |
| 1104 | regs[bits (inst2, 8, 11)] = pv_constant (constant); |
| 1105 | } |
| 1106 | |
| 1107 | else if (thumb2_instruction_changes_pc (insn, inst2)) |
| 1108 | { |
| 1109 | /* Don't scan past anything that might change control flow. */ |
| 1110 | break; |
| 1111 | } |
| 1112 | else |
| 1113 | { |
| 1114 | /* The optimizer might shove anything into the prologue, |
| 1115 | so we just skip what we don't recognize. */ |
| 1116 | unrecognized_pc = start; |
| 1117 | } |
| 1118 | |
| 1119 | start += 2; |
| 1120 | } |
| 1121 | else if (thumb_instruction_changes_pc (insn)) |
| 1122 | { |
| 1123 | /* Don't scan past anything that might change control flow. */ |
| 1124 | break; |
| 1125 | } |
| 1126 | else |
| 1127 | { |
| 1128 | /* The optimizer might shove anything into the prologue, |
| 1129 | so we just skip what we don't recognize. */ |
| 1130 | unrecognized_pc = start; |
| 1131 | } |
| 1132 | |
| 1133 | start += 2; |
| 1134 | } |
| 1135 | |
| 1136 | if (arm_debug) |
| 1137 | fprintf_unfiltered (gdb_stdlog, "Prologue scan stopped at %s\n", |
| 1138 | paddress (gdbarch, start)); |
| 1139 | |
| 1140 | if (unrecognized_pc == 0) |
| 1141 | unrecognized_pc = start; |
| 1142 | |
| 1143 | if (cache == NULL) |
| 1144 | { |
| 1145 | do_cleanups (back_to); |
| 1146 | return unrecognized_pc; |
| 1147 | } |
| 1148 | |
| 1149 | if (pv_is_register (regs[ARM_FP_REGNUM], ARM_SP_REGNUM)) |
| 1150 | { |
| 1151 | /* Frame pointer is fp. Frame size is constant. */ |
| 1152 | cache->framereg = ARM_FP_REGNUM; |
| 1153 | cache->framesize = -regs[ARM_FP_REGNUM].k; |
| 1154 | } |
| 1155 | else if (pv_is_register (regs[THUMB_FP_REGNUM], ARM_SP_REGNUM)) |
| 1156 | { |
| 1157 | /* Frame pointer is r7. Frame size is constant. */ |
| 1158 | cache->framereg = THUMB_FP_REGNUM; |
| 1159 | cache->framesize = -regs[THUMB_FP_REGNUM].k; |
| 1160 | } |
| 1161 | else if (pv_is_register (regs[ARM_SP_REGNUM], ARM_SP_REGNUM)) |
| 1162 | { |
| 1163 | /* Try the stack pointer... this is a bit desperate. */ |
| 1164 | cache->framereg = ARM_SP_REGNUM; |
| 1165 | cache->framesize = -regs[ARM_SP_REGNUM].k; |
| 1166 | } |
| 1167 | else |
| 1168 | { |
| 1169 | /* We're just out of luck. We don't know where the frame is. */ |
| 1170 | cache->framereg = -1; |
| 1171 | cache->framesize = 0; |
| 1172 | } |
| 1173 | |
| 1174 | for (i = 0; i < 16; i++) |
| 1175 | if (pv_area_find_reg (stack, gdbarch, i, &offset)) |
| 1176 | cache->saved_regs[i].addr = offset; |
| 1177 | |
| 1178 | do_cleanups (back_to); |
| 1179 | return unrecognized_pc; |
| 1180 | } |
| 1181 | |
| 1182 | |
| 1183 | /* Try to analyze the instructions starting from PC, which load symbol |
| 1184 | __stack_chk_guard. Return the address of instruction after loading this |
| 1185 | symbol, set the dest register number to *BASEREG, and set the size of |
| 1186 | instructions for loading symbol in OFFSET. Return 0 if instructions are |
| 1187 | not recognized. */ |
| 1188 | |
| 1189 | static CORE_ADDR |
| 1190 | arm_analyze_load_stack_chk_guard(CORE_ADDR pc, struct gdbarch *gdbarch, |
| 1191 | unsigned int *destreg, int *offset) |
| 1192 | { |
| 1193 | enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch); |
| 1194 | int is_thumb = arm_pc_is_thumb (gdbarch, pc); |
| 1195 | unsigned int low, high, address; |
| 1196 | |
| 1197 | address = 0; |
| 1198 | if (is_thumb) |
| 1199 | { |
| 1200 | unsigned short insn1 |
| 1201 | = read_memory_unsigned_integer (pc, 2, byte_order_for_code); |
| 1202 | |
| 1203 | if ((insn1 & 0xf800) == 0x4800) /* ldr Rd, #immed */ |
| 1204 | { |
| 1205 | *destreg = bits (insn1, 8, 10); |
| 1206 | *offset = 2; |
| 1207 | address = bits (insn1, 0, 7); |
| 1208 | } |
| 1209 | else if ((insn1 & 0xfbf0) == 0xf240) /* movw Rd, #const */ |
| 1210 | { |
| 1211 | unsigned short insn2 |
| 1212 | = read_memory_unsigned_integer (pc + 2, 2, byte_order_for_code); |
| 1213 | |
| 1214 | low = EXTRACT_MOVW_MOVT_IMM_T (insn1, insn2); |
| 1215 | |
| 1216 | insn1 |
| 1217 | = read_memory_unsigned_integer (pc + 4, 2, byte_order_for_code); |
| 1218 | insn2 |
| 1219 | = read_memory_unsigned_integer (pc + 6, 2, byte_order_for_code); |
| 1220 | |
| 1221 | /* movt Rd, #const */ |
| 1222 | if ((insn1 & 0xfbc0) == 0xf2c0) |
| 1223 | { |
| 1224 | high = EXTRACT_MOVW_MOVT_IMM_T (insn1, insn2); |
| 1225 | *destreg = bits (insn2, 8, 11); |
| 1226 | *offset = 8; |
| 1227 | address = (high << 16 | low); |
| 1228 | } |
| 1229 | } |
| 1230 | } |
| 1231 | else |
| 1232 | { |
| 1233 | unsigned int insn |
| 1234 | = read_memory_unsigned_integer (pc, 4, byte_order_for_code); |
| 1235 | |
| 1236 | if ((insn & 0x0e5f0000) == 0x041f0000) /* ldr Rd, #immed */ |
| 1237 | { |
| 1238 | address = bits (insn, 0, 11); |
| 1239 | *destreg = bits (insn, 12, 15); |
| 1240 | *offset = 4; |
| 1241 | } |
| 1242 | else if ((insn & 0x0ff00000) == 0x03000000) /* movw Rd, #const */ |
| 1243 | { |
| 1244 | low = EXTRACT_MOVW_MOVT_IMM_A (insn); |
| 1245 | |
| 1246 | insn |
| 1247 | = read_memory_unsigned_integer (pc + 4, 4, byte_order_for_code); |
| 1248 | |
| 1249 | if ((insn & 0x0ff00000) == 0x03400000) /* movt Rd, #const */ |
| 1250 | { |
| 1251 | high = EXTRACT_MOVW_MOVT_IMM_A (insn); |
| 1252 | *destreg = bits (insn, 12, 15); |
| 1253 | *offset = 8; |
| 1254 | address = (high << 16 | low); |
| 1255 | } |
| 1256 | } |
| 1257 | } |
| 1258 | |
| 1259 | return address; |
| 1260 | } |
| 1261 | |
| 1262 | /* Try to skip a sequence of instructions used for stack protector. If PC |
| 1263 | points to the first instruction of this sequence, return the address of |
| 1264 | first instruction after this sequence, otherwise, return original PC. |
| 1265 | |
| 1266 | On arm, this sequence of instructions is composed of mainly three steps, |
| 1267 | Step 1: load symbol __stack_chk_guard, |
| 1268 | Step 2: load from address of __stack_chk_guard, |
| 1269 | Step 3: store it to somewhere else. |
| 1270 | |
| 1271 | Usually, instructions on step 2 and step 3 are the same on various ARM |
| 1272 | architectures. On step 2, it is one instruction 'ldr Rx, [Rn, #0]', and |
| 1273 | on step 3, it is also one instruction 'str Rx, [r7, #immd]'. However, |
| 1274 | instructions in step 1 vary from different ARM architectures. On ARMv7, |
| 1275 | they are, |
| 1276 | |
| 1277 | movw Rn, #:lower16:__stack_chk_guard |
| 1278 | movt Rn, #:upper16:__stack_chk_guard |
| 1279 | |
| 1280 | On ARMv5t, it is, |
| 1281 | |
| 1282 | ldr Rn, .Label |
| 1283 | .... |
| 1284 | .Lable: |
| 1285 | .word __stack_chk_guard |
| 1286 | |
| 1287 | Since ldr/str is a very popular instruction, we can't use them as |
| 1288 | 'fingerprint' or 'signature' of stack protector sequence. Here we choose |
| 1289 | sequence {movw/movt, ldr}/ldr/str plus symbol __stack_chk_guard, if not |
| 1290 | stripped, as the 'fingerprint' of a stack protector cdoe sequence. */ |
| 1291 | |
| 1292 | static CORE_ADDR |
| 1293 | arm_skip_stack_protector(CORE_ADDR pc, struct gdbarch *gdbarch) |
| 1294 | { |
| 1295 | enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch); |
| 1296 | unsigned int address, basereg; |
| 1297 | struct minimal_symbol *stack_chk_guard; |
| 1298 | int offset; |
| 1299 | int is_thumb = arm_pc_is_thumb (gdbarch, pc); |
| 1300 | CORE_ADDR addr; |
| 1301 | |
| 1302 | /* Try to parse the instructions in Step 1. */ |
| 1303 | addr = arm_analyze_load_stack_chk_guard (pc, gdbarch, |
| 1304 | &basereg, &offset); |
| 1305 | if (!addr) |
| 1306 | return pc; |
| 1307 | |
| 1308 | stack_chk_guard = lookup_minimal_symbol_by_pc (addr); |
| 1309 | /* If name of symbol doesn't start with '__stack_chk_guard', this |
| 1310 | instruction sequence is not for stack protector. If symbol is |
| 1311 | removed, we conservatively think this sequence is for stack protector. */ |
| 1312 | if (stack_chk_guard |
| 1313 | && strncmp (SYMBOL_LINKAGE_NAME (stack_chk_guard), "__stack_chk_guard", |
| 1314 | strlen ("__stack_chk_guard")) != 0) |
| 1315 | return pc; |
| 1316 | |
| 1317 | if (is_thumb) |
| 1318 | { |
| 1319 | unsigned int destreg; |
| 1320 | unsigned short insn |
| 1321 | = read_memory_unsigned_integer (pc + offset, 2, byte_order_for_code); |
| 1322 | |
| 1323 | /* Step 2: ldr Rd, [Rn, #immed], encoding T1. */ |
| 1324 | if ((insn & 0xf800) != 0x6800) |
| 1325 | return pc; |
| 1326 | if (bits (insn, 3, 5) != basereg) |
| 1327 | return pc; |
| 1328 | destreg = bits (insn, 0, 2); |
| 1329 | |
| 1330 | insn = read_memory_unsigned_integer (pc + offset + 2, 2, |
| 1331 | byte_order_for_code); |
| 1332 | /* Step 3: str Rd, [Rn, #immed], encoding T1. */ |
| 1333 | if ((insn & 0xf800) != 0x6000) |
| 1334 | return pc; |
| 1335 | if (destreg != bits (insn, 0, 2)) |
| 1336 | return pc; |
| 1337 | } |
| 1338 | else |
| 1339 | { |
| 1340 | unsigned int destreg; |
| 1341 | unsigned int insn |
| 1342 | = read_memory_unsigned_integer (pc + offset, 4, byte_order_for_code); |
| 1343 | |
| 1344 | /* Step 2: ldr Rd, [Rn, #immed], encoding A1. */ |
| 1345 | if ((insn & 0x0e500000) != 0x04100000) |
| 1346 | return pc; |
| 1347 | if (bits (insn, 16, 19) != basereg) |
| 1348 | return pc; |
| 1349 | destreg = bits (insn, 12, 15); |
| 1350 | /* Step 3: str Rd, [Rn, #immed], encoding A1. */ |
| 1351 | insn = read_memory_unsigned_integer (pc + offset + 4, |
| 1352 | 4, byte_order_for_code); |
| 1353 | if ((insn & 0x0e500000) != 0x04000000) |
| 1354 | return pc; |
| 1355 | if (bits (insn, 12, 15) != destreg) |
| 1356 | return pc; |
| 1357 | } |
| 1358 | /* The size of total two instructions ldr/str is 4 on Thumb-2, while 8 |
| 1359 | on arm. */ |
| 1360 | if (is_thumb) |
| 1361 | return pc + offset + 4; |
| 1362 | else |
| 1363 | return pc + offset + 8; |
| 1364 | } |
| 1365 | |
| 1366 | /* Advance the PC across any function entry prologue instructions to |
| 1367 | reach some "real" code. |
| 1368 | |
| 1369 | The APCS (ARM Procedure Call Standard) defines the following |
| 1370 | prologue: |
| 1371 | |
| 1372 | mov ip, sp |
| 1373 | [stmfd sp!, {a1,a2,a3,a4}] |
| 1374 | stmfd sp!, {...,fp,ip,lr,pc} |
| 1375 | [stfe f7, [sp, #-12]!] |
| 1376 | [stfe f6, [sp, #-12]!] |
| 1377 | [stfe f5, [sp, #-12]!] |
| 1378 | [stfe f4, [sp, #-12]!] |
| 1379 | sub fp, ip, #nn @@ nn == 20 or 4 depending on second insn. */ |
| 1380 | |
| 1381 | static CORE_ADDR |
| 1382 | arm_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 1383 | { |
| 1384 | enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch); |
| 1385 | unsigned long inst; |
| 1386 | CORE_ADDR skip_pc; |
| 1387 | CORE_ADDR func_addr, limit_pc; |
| 1388 | struct symtab_and_line sal; |
| 1389 | |
| 1390 | /* See if we can determine the end of the prologue via the symbol table. |
| 1391 | If so, then return either PC, or the PC after the prologue, whichever |
| 1392 | is greater. */ |
| 1393 | if (find_pc_partial_function (pc, NULL, &func_addr, NULL)) |
| 1394 | { |
| 1395 | CORE_ADDR post_prologue_pc |
| 1396 | = skip_prologue_using_sal (gdbarch, func_addr); |
| 1397 | struct symtab *s = find_pc_symtab (func_addr); |
| 1398 | |
| 1399 | if (post_prologue_pc) |
| 1400 | post_prologue_pc |
| 1401 | = arm_skip_stack_protector (post_prologue_pc, gdbarch); |
| 1402 | |
| 1403 | |
| 1404 | /* GCC always emits a line note before the prologue and another |
| 1405 | one after, even if the two are at the same address or on the |
| 1406 | same line. Take advantage of this so that we do not need to |
| 1407 | know every instruction that might appear in the prologue. We |
| 1408 | will have producer information for most binaries; if it is |
| 1409 | missing (e.g. for -gstabs), assuming the GNU tools. */ |
| 1410 | if (post_prologue_pc |
| 1411 | && (s == NULL |
| 1412 | || s->producer == NULL |
| 1413 | || strncmp (s->producer, "GNU ", sizeof ("GNU ") - 1) == 0)) |
| 1414 | return post_prologue_pc; |
| 1415 | |
| 1416 | if (post_prologue_pc != 0) |
| 1417 | { |
| 1418 | CORE_ADDR analyzed_limit; |
| 1419 | |
| 1420 | /* For non-GCC compilers, make sure the entire line is an |
| 1421 | acceptable prologue; GDB will round this function's |
| 1422 | return value up to the end of the following line so we |
| 1423 | can not skip just part of a line (and we do not want to). |
| 1424 | |
| 1425 | RealView does not treat the prologue specially, but does |
| 1426 | associate prologue code with the opening brace; so this |
| 1427 | lets us skip the first line if we think it is the opening |
| 1428 | brace. */ |
| 1429 | if (arm_pc_is_thumb (gdbarch, func_addr)) |
| 1430 | analyzed_limit = thumb_analyze_prologue (gdbarch, func_addr, |
| 1431 | post_prologue_pc, NULL); |
| 1432 | else |
| 1433 | analyzed_limit = arm_analyze_prologue (gdbarch, func_addr, |
| 1434 | post_prologue_pc, NULL); |
| 1435 | |
| 1436 | if (analyzed_limit != post_prologue_pc) |
| 1437 | return func_addr; |
| 1438 | |
| 1439 | return post_prologue_pc; |
| 1440 | } |
| 1441 | } |
| 1442 | |
| 1443 | /* Can't determine prologue from the symbol table, need to examine |
| 1444 | instructions. */ |
| 1445 | |
| 1446 | /* Find an upper limit on the function prologue using the debug |
| 1447 | information. If the debug information could not be used to provide |
| 1448 | that bound, then use an arbitrary large number as the upper bound. */ |
| 1449 | /* Like arm_scan_prologue, stop no later than pc + 64. */ |
| 1450 | limit_pc = skip_prologue_using_sal (gdbarch, pc); |
| 1451 | if (limit_pc == 0) |
| 1452 | limit_pc = pc + 64; /* Magic. */ |
| 1453 | |
| 1454 | |
| 1455 | /* Check if this is Thumb code. */ |
| 1456 | if (arm_pc_is_thumb (gdbarch, pc)) |
| 1457 | return thumb_analyze_prologue (gdbarch, pc, limit_pc, NULL); |
| 1458 | |
| 1459 | for (skip_pc = pc; skip_pc < limit_pc; skip_pc += 4) |
| 1460 | { |
| 1461 | inst = read_memory_unsigned_integer (skip_pc, 4, byte_order_for_code); |
| 1462 | |
| 1463 | /* "mov ip, sp" is no longer a required part of the prologue. */ |
| 1464 | if (inst == 0xe1a0c00d) /* mov ip, sp */ |
| 1465 | continue; |
| 1466 | |
| 1467 | if ((inst & 0xfffff000) == 0xe28dc000) /* add ip, sp #n */ |
| 1468 | continue; |
| 1469 | |
| 1470 | if ((inst & 0xfffff000) == 0xe24dc000) /* sub ip, sp #n */ |
| 1471 | continue; |
| 1472 | |
| 1473 | /* Some prologues begin with "str lr, [sp, #-4]!". */ |
| 1474 | if (inst == 0xe52de004) /* str lr, [sp, #-4]! */ |
| 1475 | continue; |
| 1476 | |
| 1477 | if ((inst & 0xfffffff0) == 0xe92d0000) /* stmfd sp!,{a1,a2,a3,a4} */ |
| 1478 | continue; |
| 1479 | |
| 1480 | if ((inst & 0xfffff800) == 0xe92dd800) /* stmfd sp!,{fp,ip,lr,pc} */ |
| 1481 | continue; |
| 1482 | |
| 1483 | /* Any insns after this point may float into the code, if it makes |
| 1484 | for better instruction scheduling, so we skip them only if we |
| 1485 | find them, but still consider the function to be frame-ful. */ |
| 1486 | |
| 1487 | /* We may have either one sfmfd instruction here, or several stfe |
| 1488 | insns, depending on the version of floating point code we |
| 1489 | support. */ |
| 1490 | if ((inst & 0xffbf0fff) == 0xec2d0200) /* sfmfd fn, <cnt>, [sp]! */ |
| 1491 | continue; |
| 1492 | |
| 1493 | if ((inst & 0xffff8fff) == 0xed6d0103) /* stfe fn, [sp, #-12]! */ |
| 1494 | continue; |
| 1495 | |
| 1496 | if ((inst & 0xfffff000) == 0xe24cb000) /* sub fp, ip, #nn */ |
| 1497 | continue; |
| 1498 | |
| 1499 | if ((inst & 0xfffff000) == 0xe24dd000) /* sub sp, sp, #nn */ |
| 1500 | continue; |
| 1501 | |
| 1502 | if ((inst & 0xffffc000) == 0xe54b0000 /* strb r(0123),[r11,#-nn] */ |
| 1503 | || (inst & 0xffffc0f0) == 0xe14b00b0 /* strh r(0123),[r11,#-nn] */ |
| 1504 | || (inst & 0xffffc000) == 0xe50b0000) /* str r(0123),[r11,#-nn] */ |
| 1505 | continue; |
| 1506 | |
| 1507 | if ((inst & 0xffffc000) == 0xe5cd0000 /* strb r(0123),[sp,#nn] */ |
| 1508 | || (inst & 0xffffc0f0) == 0xe1cd00b0 /* strh r(0123),[sp,#nn] */ |
| 1509 | || (inst & 0xffffc000) == 0xe58d0000) /* str r(0123),[sp,#nn] */ |
| 1510 | continue; |
| 1511 | |
| 1512 | /* Un-recognized instruction; stop scanning. */ |
| 1513 | break; |
| 1514 | } |
| 1515 | |
| 1516 | return skip_pc; /* End of prologue. */ |
| 1517 | } |
| 1518 | |
| 1519 | /* *INDENT-OFF* */ |
| 1520 | /* Function: thumb_scan_prologue (helper function for arm_scan_prologue) |
| 1521 | This function decodes a Thumb function prologue to determine: |
| 1522 | 1) the size of the stack frame |
| 1523 | 2) which registers are saved on it |
| 1524 | 3) the offsets of saved regs |
| 1525 | 4) the offset from the stack pointer to the frame pointer |
| 1526 | |
| 1527 | A typical Thumb function prologue would create this stack frame |
| 1528 | (offsets relative to FP) |
| 1529 | old SP -> 24 stack parameters |
| 1530 | 20 LR |
| 1531 | 16 R7 |
| 1532 | R7 -> 0 local variables (16 bytes) |
| 1533 | SP -> -12 additional stack space (12 bytes) |
| 1534 | The frame size would thus be 36 bytes, and the frame offset would be |
| 1535 | 12 bytes. The frame register is R7. |
| 1536 | |
| 1537 | The comments for thumb_skip_prolog() describe the algorithm we use |
| 1538 | to detect the end of the prolog. */ |
| 1539 | /* *INDENT-ON* */ |
| 1540 | |
| 1541 | static void |
| 1542 | thumb_scan_prologue (struct gdbarch *gdbarch, CORE_ADDR prev_pc, |
| 1543 | CORE_ADDR block_addr, struct arm_prologue_cache *cache) |
| 1544 | { |
| 1545 | CORE_ADDR prologue_start; |
| 1546 | CORE_ADDR prologue_end; |
| 1547 | CORE_ADDR current_pc; |
| 1548 | |
| 1549 | if (find_pc_partial_function (block_addr, NULL, &prologue_start, |
| 1550 | &prologue_end)) |
| 1551 | { |
| 1552 | /* See comment in arm_scan_prologue for an explanation of |
| 1553 | this heuristics. */ |
| 1554 | if (prologue_end > prologue_start + 64) |
| 1555 | { |
| 1556 | prologue_end = prologue_start + 64; |
| 1557 | } |
| 1558 | } |
| 1559 | else |
| 1560 | /* We're in the boondocks: we have no idea where the start of the |
| 1561 | function is. */ |
| 1562 | return; |
| 1563 | |
| 1564 | prologue_end = min (prologue_end, prev_pc); |
| 1565 | |
| 1566 | thumb_analyze_prologue (gdbarch, prologue_start, prologue_end, cache); |
| 1567 | } |
| 1568 | |
| 1569 | /* Return 1 if THIS_INSTR might change control flow, 0 otherwise. */ |
| 1570 | |
| 1571 | static int |
| 1572 | arm_instruction_changes_pc (uint32_t this_instr) |
| 1573 | { |
| 1574 | if (bits (this_instr, 28, 31) == INST_NV) |
| 1575 | /* Unconditional instructions. */ |
| 1576 | switch (bits (this_instr, 24, 27)) |
| 1577 | { |
| 1578 | case 0xa: |
| 1579 | case 0xb: |
| 1580 | /* Branch with Link and change to Thumb. */ |
| 1581 | return 1; |
| 1582 | case 0xc: |
| 1583 | case 0xd: |
| 1584 | case 0xe: |
| 1585 | /* Coprocessor register transfer. */ |
| 1586 | if (bits (this_instr, 12, 15) == 15) |
| 1587 | error (_("Invalid update to pc in instruction")); |
| 1588 | return 0; |
| 1589 | default: |
| 1590 | return 0; |
| 1591 | } |
| 1592 | else |
| 1593 | switch (bits (this_instr, 25, 27)) |
| 1594 | { |
| 1595 | case 0x0: |
| 1596 | if (bits (this_instr, 23, 24) == 2 && bit (this_instr, 20) == 0) |
| 1597 | { |
| 1598 | /* Multiplies and extra load/stores. */ |
| 1599 | if (bit (this_instr, 4) == 1 && bit (this_instr, 7) == 1) |
| 1600 | /* Neither multiplies nor extension load/stores are allowed |
| 1601 | to modify PC. */ |
| 1602 | return 0; |
| 1603 | |
| 1604 | /* Otherwise, miscellaneous instructions. */ |
| 1605 | |
| 1606 | /* BX <reg>, BXJ <reg>, BLX <reg> */ |
| 1607 | if (bits (this_instr, 4, 27) == 0x12fff1 |
| 1608 | || bits (this_instr, 4, 27) == 0x12fff2 |
| 1609 | || bits (this_instr, 4, 27) == 0x12fff3) |
| 1610 | return 1; |
| 1611 | |
| 1612 | /* Other miscellaneous instructions are unpredictable if they |
| 1613 | modify PC. */ |
| 1614 | return 0; |
| 1615 | } |
| 1616 | /* Data processing instruction. Fall through. */ |
| 1617 | |
| 1618 | case 0x1: |
| 1619 | if (bits (this_instr, 12, 15) == 15) |
| 1620 | return 1; |
| 1621 | else |
| 1622 | return 0; |
| 1623 | |
| 1624 | case 0x2: |
| 1625 | case 0x3: |
| 1626 | /* Media instructions and architecturally undefined instructions. */ |
| 1627 | if (bits (this_instr, 25, 27) == 3 && bit (this_instr, 4) == 1) |
| 1628 | return 0; |
| 1629 | |
| 1630 | /* Stores. */ |
| 1631 | if (bit (this_instr, 20) == 0) |
| 1632 | return 0; |
| 1633 | |
| 1634 | /* Loads. */ |
| 1635 | if (bits (this_instr, 12, 15) == ARM_PC_REGNUM) |
| 1636 | return 1; |
| 1637 | else |
| 1638 | return 0; |
| 1639 | |
| 1640 | case 0x4: |
| 1641 | /* Load/store multiple. */ |
| 1642 | if (bit (this_instr, 20) == 1 && bit (this_instr, 15) == 1) |
| 1643 | return 1; |
| 1644 | else |
| 1645 | return 0; |
| 1646 | |
| 1647 | case 0x5: |
| 1648 | /* Branch and branch with link. */ |
| 1649 | return 1; |
| 1650 | |
| 1651 | case 0x6: |
| 1652 | case 0x7: |
| 1653 | /* Coprocessor transfers or SWIs can not affect PC. */ |
| 1654 | return 0; |
| 1655 | |
| 1656 | default: |
| 1657 | internal_error (__FILE__, __LINE__, _("bad value in switch")); |
| 1658 | } |
| 1659 | } |
| 1660 | |
| 1661 | /* Analyze an ARM mode prologue starting at PROLOGUE_START and |
| 1662 | continuing no further than PROLOGUE_END. If CACHE is non-NULL, |
| 1663 | fill it in. Return the first address not recognized as a prologue |
| 1664 | instruction. |
| 1665 | |
| 1666 | We recognize all the instructions typically found in ARM prologues, |
| 1667 | plus harmless instructions which can be skipped (either for analysis |
| 1668 | purposes, or a more restrictive set that can be skipped when finding |
| 1669 | the end of the prologue). */ |
| 1670 | |
| 1671 | static CORE_ADDR |
| 1672 | arm_analyze_prologue (struct gdbarch *gdbarch, |
| 1673 | CORE_ADDR prologue_start, CORE_ADDR prologue_end, |
| 1674 | struct arm_prologue_cache *cache) |
| 1675 | { |
| 1676 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 1677 | enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch); |
| 1678 | int regno; |
| 1679 | CORE_ADDR offset, current_pc; |
| 1680 | pv_t regs[ARM_FPS_REGNUM]; |
| 1681 | struct pv_area *stack; |
| 1682 | struct cleanup *back_to; |
| 1683 | int framereg, framesize; |
| 1684 | CORE_ADDR unrecognized_pc = 0; |
| 1685 | |
| 1686 | /* Search the prologue looking for instructions that set up the |
| 1687 | frame pointer, adjust the stack pointer, and save registers. |
| 1688 | |
| 1689 | Be careful, however, and if it doesn't look like a prologue, |
| 1690 | don't try to scan it. If, for instance, a frameless function |
| 1691 | begins with stmfd sp!, then we will tell ourselves there is |
| 1692 | a frame, which will confuse stack traceback, as well as "finish" |
| 1693 | and other operations that rely on a knowledge of the stack |
| 1694 | traceback. */ |
| 1695 | |
| 1696 | for (regno = 0; regno < ARM_FPS_REGNUM; regno++) |
| 1697 | regs[regno] = pv_register (regno, 0); |
| 1698 | stack = make_pv_area (ARM_SP_REGNUM, gdbarch_addr_bit (gdbarch)); |
| 1699 | back_to = make_cleanup_free_pv_area (stack); |
| 1700 | |
| 1701 | for (current_pc = prologue_start; |
| 1702 | current_pc < prologue_end; |
| 1703 | current_pc += 4) |
| 1704 | { |
| 1705 | unsigned int insn |
| 1706 | = read_memory_unsigned_integer (current_pc, 4, byte_order_for_code); |
| 1707 | |
| 1708 | if (insn == 0xe1a0c00d) /* mov ip, sp */ |
| 1709 | { |
| 1710 | regs[ARM_IP_REGNUM] = regs[ARM_SP_REGNUM]; |
| 1711 | continue; |
| 1712 | } |
| 1713 | else if ((insn & 0xfff00000) == 0xe2800000 /* add Rd, Rn, #n */ |
| 1714 | && pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM)) |
| 1715 | { |
| 1716 | unsigned imm = insn & 0xff; /* immediate value */ |
| 1717 | unsigned rot = (insn & 0xf00) >> 7; /* rotate amount */ |
| 1718 | int rd = bits (insn, 12, 15); |
| 1719 | imm = (imm >> rot) | (imm << (32 - rot)); |
| 1720 | regs[rd] = pv_add_constant (regs[bits (insn, 16, 19)], imm); |
| 1721 | continue; |
| 1722 | } |
| 1723 | else if ((insn & 0xfff00000) == 0xe2400000 /* sub Rd, Rn, #n */ |
| 1724 | && pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM)) |
| 1725 | { |
| 1726 | unsigned imm = insn & 0xff; /* immediate value */ |
| 1727 | unsigned rot = (insn & 0xf00) >> 7; /* rotate amount */ |
| 1728 | int rd = bits (insn, 12, 15); |
| 1729 | imm = (imm >> rot) | (imm << (32 - rot)); |
| 1730 | regs[rd] = pv_add_constant (regs[bits (insn, 16, 19)], -imm); |
| 1731 | continue; |
| 1732 | } |
| 1733 | else if ((insn & 0xffff0fff) == 0xe52d0004) /* str Rd, |
| 1734 | [sp, #-4]! */ |
| 1735 | { |
| 1736 | if (pv_area_store_would_trash (stack, regs[ARM_SP_REGNUM])) |
| 1737 | break; |
| 1738 | regs[ARM_SP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM], -4); |
| 1739 | pv_area_store (stack, regs[ARM_SP_REGNUM], 4, |
| 1740 | regs[bits (insn, 12, 15)]); |
| 1741 | continue; |
| 1742 | } |
| 1743 | else if ((insn & 0xffff0000) == 0xe92d0000) |
| 1744 | /* stmfd sp!, {..., fp, ip, lr, pc} |
| 1745 | or |
| 1746 | stmfd sp!, {a1, a2, a3, a4} */ |
| 1747 | { |
| 1748 | int mask = insn & 0xffff; |
| 1749 | |
| 1750 | if (pv_area_store_would_trash (stack, regs[ARM_SP_REGNUM])) |
| 1751 | break; |
| 1752 | |
| 1753 | /* Calculate offsets of saved registers. */ |
| 1754 | for (regno = ARM_PC_REGNUM; regno >= 0; regno--) |
| 1755 | if (mask & (1 << regno)) |
| 1756 | { |
| 1757 | regs[ARM_SP_REGNUM] |
| 1758 | = pv_add_constant (regs[ARM_SP_REGNUM], -4); |
| 1759 | pv_area_store (stack, regs[ARM_SP_REGNUM], 4, regs[regno]); |
| 1760 | } |
| 1761 | } |
| 1762 | else if ((insn & 0xffff0000) == 0xe54b0000 /* strb rx,[r11,#-n] */ |
| 1763 | || (insn & 0xffff00f0) == 0xe14b00b0 /* strh rx,[r11,#-n] */ |
| 1764 | || (insn & 0xffffc000) == 0xe50b0000) /* str rx,[r11,#-n] */ |
| 1765 | { |
| 1766 | /* No need to add this to saved_regs -- it's just an arg reg. */ |
| 1767 | continue; |
| 1768 | } |
| 1769 | else if ((insn & 0xffff0000) == 0xe5cd0000 /* strb rx,[sp,#n] */ |
| 1770 | || (insn & 0xffff00f0) == 0xe1cd00b0 /* strh rx,[sp,#n] */ |
| 1771 | || (insn & 0xffffc000) == 0xe58d0000) /* str rx,[sp,#n] */ |
| 1772 | { |
| 1773 | /* No need to add this to saved_regs -- it's just an arg reg. */ |
| 1774 | continue; |
| 1775 | } |
| 1776 | else if ((insn & 0xfff00000) == 0xe8800000 /* stm Rn, |
| 1777 | { registers } */ |
| 1778 | && pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM)) |
| 1779 | { |
| 1780 | /* No need to add this to saved_regs -- it's just arg regs. */ |
| 1781 | continue; |
| 1782 | } |
| 1783 | else if ((insn & 0xfffff000) == 0xe24cb000) /* sub fp, ip #n */ |
| 1784 | { |
| 1785 | unsigned imm = insn & 0xff; /* immediate value */ |
| 1786 | unsigned rot = (insn & 0xf00) >> 7; /* rotate amount */ |
| 1787 | imm = (imm >> rot) | (imm << (32 - rot)); |
| 1788 | regs[ARM_FP_REGNUM] = pv_add_constant (regs[ARM_IP_REGNUM], -imm); |
| 1789 | } |
| 1790 | else if ((insn & 0xfffff000) == 0xe24dd000) /* sub sp, sp #n */ |
| 1791 | { |
| 1792 | unsigned imm = insn & 0xff; /* immediate value */ |
| 1793 | unsigned rot = (insn & 0xf00) >> 7; /* rotate amount */ |
| 1794 | imm = (imm >> rot) | (imm << (32 - rot)); |
| 1795 | regs[ARM_SP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM], -imm); |
| 1796 | } |
| 1797 | else if ((insn & 0xffff7fff) == 0xed6d0103 /* stfe f?, |
| 1798 | [sp, -#c]! */ |
| 1799 | && gdbarch_tdep (gdbarch)->have_fpa_registers) |
| 1800 | { |
| 1801 | if (pv_area_store_would_trash (stack, regs[ARM_SP_REGNUM])) |
| 1802 | break; |
| 1803 | |
| 1804 | regs[ARM_SP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM], -12); |
| 1805 | regno = ARM_F0_REGNUM + ((insn >> 12) & 0x07); |
| 1806 | pv_area_store (stack, regs[ARM_SP_REGNUM], 12, regs[regno]); |
| 1807 | } |
| 1808 | else if ((insn & 0xffbf0fff) == 0xec2d0200 /* sfmfd f0, 4, |
| 1809 | [sp!] */ |
| 1810 | && gdbarch_tdep (gdbarch)->have_fpa_registers) |
| 1811 | { |
| 1812 | int n_saved_fp_regs; |
| 1813 | unsigned int fp_start_reg, fp_bound_reg; |
| 1814 | |
| 1815 | if (pv_area_store_would_trash (stack, regs[ARM_SP_REGNUM])) |
| 1816 | break; |
| 1817 | |
| 1818 | if ((insn & 0x800) == 0x800) /* N0 is set */ |
| 1819 | { |
| 1820 | if ((insn & 0x40000) == 0x40000) /* N1 is set */ |
| 1821 | n_saved_fp_regs = 3; |
| 1822 | else |
| 1823 | n_saved_fp_regs = 1; |
| 1824 | } |
| 1825 | else |
| 1826 | { |
| 1827 | if ((insn & 0x40000) == 0x40000) /* N1 is set */ |
| 1828 | n_saved_fp_regs = 2; |
| 1829 | else |
| 1830 | n_saved_fp_regs = 4; |
| 1831 | } |
| 1832 | |
| 1833 | fp_start_reg = ARM_F0_REGNUM + ((insn >> 12) & 0x7); |
| 1834 | fp_bound_reg = fp_start_reg + n_saved_fp_regs; |
| 1835 | for (; fp_start_reg < fp_bound_reg; fp_start_reg++) |
| 1836 | { |
| 1837 | regs[ARM_SP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM], -12); |
| 1838 | pv_area_store (stack, regs[ARM_SP_REGNUM], 12, |
| 1839 | regs[fp_start_reg++]); |
| 1840 | } |
| 1841 | } |
| 1842 | else if ((insn & 0xff000000) == 0xeb000000 && cache == NULL) /* bl */ |
| 1843 | { |
| 1844 | /* Allow some special function calls when skipping the |
| 1845 | prologue; GCC generates these before storing arguments to |
| 1846 | the stack. */ |
| 1847 | CORE_ADDR dest = BranchDest (current_pc, insn); |
| 1848 | |
| 1849 | if (skip_prologue_function (gdbarch, dest, 0)) |
| 1850 | continue; |
| 1851 | else |
| 1852 | break; |
| 1853 | } |
| 1854 | else if ((insn & 0xf0000000) != 0xe0000000) |
| 1855 | break; /* Condition not true, exit early. */ |
| 1856 | else if (arm_instruction_changes_pc (insn)) |
| 1857 | /* Don't scan past anything that might change control flow. */ |
| 1858 | break; |
| 1859 | else if ((insn & 0xfe500000) == 0xe8100000) /* ldm */ |
| 1860 | { |
| 1861 | /* Ignore block loads from the stack, potentially copying |
| 1862 | parameters from memory. */ |
| 1863 | if (pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM)) |
| 1864 | continue; |
| 1865 | else |
| 1866 | break; |
| 1867 | } |
| 1868 | else if ((insn & 0xfc500000) == 0xe4100000) |
| 1869 | { |
| 1870 | /* Similarly ignore single loads from the stack. */ |
| 1871 | if (pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM)) |
| 1872 | continue; |
| 1873 | else |
| 1874 | break; |
| 1875 | } |
| 1876 | else if ((insn & 0xffff0ff0) == 0xe1a00000) |
| 1877 | /* MOV Rd, Rm. Skip register copies, i.e. saves to another |
| 1878 | register instead of the stack. */ |
| 1879 | continue; |
| 1880 | else |
| 1881 | { |
| 1882 | /* The optimizer might shove anything into the prologue, |
| 1883 | so we just skip what we don't recognize. */ |
| 1884 | unrecognized_pc = current_pc; |
| 1885 | continue; |
| 1886 | } |
| 1887 | } |
| 1888 | |
| 1889 | if (unrecognized_pc == 0) |
| 1890 | unrecognized_pc = current_pc; |
| 1891 | |
| 1892 | /* The frame size is just the distance from the frame register |
| 1893 | to the original stack pointer. */ |
| 1894 | if (pv_is_register (regs[ARM_FP_REGNUM], ARM_SP_REGNUM)) |
| 1895 | { |
| 1896 | /* Frame pointer is fp. */ |
| 1897 | framereg = ARM_FP_REGNUM; |
| 1898 | framesize = -regs[ARM_FP_REGNUM].k; |
| 1899 | } |
| 1900 | else if (pv_is_register (regs[ARM_SP_REGNUM], ARM_SP_REGNUM)) |
| 1901 | { |
| 1902 | /* Try the stack pointer... this is a bit desperate. */ |
| 1903 | framereg = ARM_SP_REGNUM; |
| 1904 | framesize = -regs[ARM_SP_REGNUM].k; |
| 1905 | } |
| 1906 | else |
| 1907 | { |
| 1908 | /* We're just out of luck. We don't know where the frame is. */ |
| 1909 | framereg = -1; |
| 1910 | framesize = 0; |
| 1911 | } |
| 1912 | |
| 1913 | if (cache) |
| 1914 | { |
| 1915 | cache->framereg = framereg; |
| 1916 | cache->framesize = framesize; |
| 1917 | |
| 1918 | for (regno = 0; regno < ARM_FPS_REGNUM; regno++) |
| 1919 | if (pv_area_find_reg (stack, gdbarch, regno, &offset)) |
| 1920 | cache->saved_regs[regno].addr = offset; |
| 1921 | } |
| 1922 | |
| 1923 | if (arm_debug) |
| 1924 | fprintf_unfiltered (gdb_stdlog, "Prologue scan stopped at %s\n", |
| 1925 | paddress (gdbarch, unrecognized_pc)); |
| 1926 | |
| 1927 | do_cleanups (back_to); |
| 1928 | return unrecognized_pc; |
| 1929 | } |
| 1930 | |
| 1931 | static void |
| 1932 | arm_scan_prologue (struct frame_info *this_frame, |
| 1933 | struct arm_prologue_cache *cache) |
| 1934 | { |
| 1935 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| 1936 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 1937 | int regno; |
| 1938 | CORE_ADDR prologue_start, prologue_end, current_pc; |
| 1939 | CORE_ADDR prev_pc = get_frame_pc (this_frame); |
| 1940 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); |
| 1941 | pv_t regs[ARM_FPS_REGNUM]; |
| 1942 | struct pv_area *stack; |
| 1943 | struct cleanup *back_to; |
| 1944 | CORE_ADDR offset; |
| 1945 | |
| 1946 | /* Assume there is no frame until proven otherwise. */ |
| 1947 | cache->framereg = ARM_SP_REGNUM; |
| 1948 | cache->framesize = 0; |
| 1949 | |
| 1950 | /* Check for Thumb prologue. */ |
| 1951 | if (arm_frame_is_thumb (this_frame)) |
| 1952 | { |
| 1953 | thumb_scan_prologue (gdbarch, prev_pc, block_addr, cache); |
| 1954 | return; |
| 1955 | } |
| 1956 | |
| 1957 | /* Find the function prologue. If we can't find the function in |
| 1958 | the symbol table, peek in the stack frame to find the PC. */ |
| 1959 | if (find_pc_partial_function (block_addr, NULL, &prologue_start, |
| 1960 | &prologue_end)) |
| 1961 | { |
| 1962 | /* One way to find the end of the prologue (which works well |
| 1963 | for unoptimized code) is to do the following: |
| 1964 | |
| 1965 | struct symtab_and_line sal = find_pc_line (prologue_start, 0); |
| 1966 | |
| 1967 | if (sal.line == 0) |
| 1968 | prologue_end = prev_pc; |
| 1969 | else if (sal.end < prologue_end) |
| 1970 | prologue_end = sal.end; |
| 1971 | |
| 1972 | This mechanism is very accurate so long as the optimizer |
| 1973 | doesn't move any instructions from the function body into the |
| 1974 | prologue. If this happens, sal.end will be the last |
| 1975 | instruction in the first hunk of prologue code just before |
| 1976 | the first instruction that the scheduler has moved from |
| 1977 | the body to the prologue. |
| 1978 | |
| 1979 | In order to make sure that we scan all of the prologue |
| 1980 | instructions, we use a slightly less accurate mechanism which |
| 1981 | may scan more than necessary. To help compensate for this |
| 1982 | lack of accuracy, the prologue scanning loop below contains |
| 1983 | several clauses which'll cause the loop to terminate early if |
| 1984 | an implausible prologue instruction is encountered. |
| 1985 | |
| 1986 | The expression |
| 1987 | |
| 1988 | prologue_start + 64 |
| 1989 | |
| 1990 | is a suitable endpoint since it accounts for the largest |
| 1991 | possible prologue plus up to five instructions inserted by |
| 1992 | the scheduler. */ |
| 1993 | |
| 1994 | if (prologue_end > prologue_start + 64) |
| 1995 | { |
| 1996 | prologue_end = prologue_start + 64; /* See above. */ |
| 1997 | } |
| 1998 | } |
| 1999 | else |
| 2000 | { |
| 2001 | /* We have no symbol information. Our only option is to assume this |
| 2002 | function has a standard stack frame and the normal frame register. |
| 2003 | Then, we can find the value of our frame pointer on entrance to |
| 2004 | the callee (or at the present moment if this is the innermost frame). |
| 2005 | The value stored there should be the address of the stmfd + 8. */ |
| 2006 | CORE_ADDR frame_loc; |
| 2007 | LONGEST return_value; |
| 2008 | |
| 2009 | frame_loc = get_frame_register_unsigned (this_frame, ARM_FP_REGNUM); |
| 2010 | if (!safe_read_memory_integer (frame_loc, 4, byte_order, &return_value)) |
| 2011 | return; |
| 2012 | else |
| 2013 | { |
| 2014 | prologue_start = gdbarch_addr_bits_remove |
| 2015 | (gdbarch, return_value) - 8; |
| 2016 | prologue_end = prologue_start + 64; /* See above. */ |
| 2017 | } |
| 2018 | } |
| 2019 | |
| 2020 | if (prev_pc < prologue_end) |
| 2021 | prologue_end = prev_pc; |
| 2022 | |
| 2023 | arm_analyze_prologue (gdbarch, prologue_start, prologue_end, cache); |
| 2024 | } |
| 2025 | |
| 2026 | static struct arm_prologue_cache * |
| 2027 | arm_make_prologue_cache (struct frame_info *this_frame) |
| 2028 | { |
| 2029 | int reg; |
| 2030 | struct arm_prologue_cache *cache; |
| 2031 | CORE_ADDR unwound_fp; |
| 2032 | |
| 2033 | cache = FRAME_OBSTACK_ZALLOC (struct arm_prologue_cache); |
| 2034 | cache->saved_regs = trad_frame_alloc_saved_regs (this_frame); |
| 2035 | |
| 2036 | arm_scan_prologue (this_frame, cache); |
| 2037 | |
| 2038 | unwound_fp = get_frame_register_unsigned (this_frame, cache->framereg); |
| 2039 | if (unwound_fp == 0) |
| 2040 | return cache; |
| 2041 | |
| 2042 | cache->prev_sp = unwound_fp + cache->framesize; |
| 2043 | |
| 2044 | /* Calculate actual addresses of saved registers using offsets |
| 2045 | determined by arm_scan_prologue. */ |
| 2046 | for (reg = 0; reg < gdbarch_num_regs (get_frame_arch (this_frame)); reg++) |
| 2047 | if (trad_frame_addr_p (cache->saved_regs, reg)) |
| 2048 | cache->saved_regs[reg].addr += cache->prev_sp; |
| 2049 | |
| 2050 | return cache; |
| 2051 | } |
| 2052 | |
| 2053 | /* Our frame ID for a normal frame is the current function's starting PC |
| 2054 | and the caller's SP when we were called. */ |
| 2055 | |
| 2056 | static void |
| 2057 | arm_prologue_this_id (struct frame_info *this_frame, |
| 2058 | void **this_cache, |
| 2059 | struct frame_id *this_id) |
| 2060 | { |
| 2061 | struct arm_prologue_cache *cache; |
| 2062 | struct frame_id id; |
| 2063 | CORE_ADDR pc, func; |
| 2064 | |
| 2065 | if (*this_cache == NULL) |
| 2066 | *this_cache = arm_make_prologue_cache (this_frame); |
| 2067 | cache = *this_cache; |
| 2068 | |
| 2069 | /* This is meant to halt the backtrace at "_start". */ |
| 2070 | pc = get_frame_pc (this_frame); |
| 2071 | if (pc <= gdbarch_tdep (get_frame_arch (this_frame))->lowest_pc) |
| 2072 | return; |
| 2073 | |
| 2074 | /* If we've hit a wall, stop. */ |
| 2075 | if (cache->prev_sp == 0) |
| 2076 | return; |
| 2077 | |
| 2078 | /* Use function start address as part of the frame ID. If we cannot |
| 2079 | identify the start address (due to missing symbol information), |
| 2080 | fall back to just using the current PC. */ |
| 2081 | func = get_frame_func (this_frame); |
| 2082 | if (!func) |
| 2083 | func = pc; |
| 2084 | |
| 2085 | id = frame_id_build (cache->prev_sp, func); |
| 2086 | *this_id = id; |
| 2087 | } |
| 2088 | |
| 2089 | static struct value * |
| 2090 | arm_prologue_prev_register (struct frame_info *this_frame, |
| 2091 | void **this_cache, |
| 2092 | int prev_regnum) |
| 2093 | { |
| 2094 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| 2095 | struct arm_prologue_cache *cache; |
| 2096 | |
| 2097 | if (*this_cache == NULL) |
| 2098 | *this_cache = arm_make_prologue_cache (this_frame); |
| 2099 | cache = *this_cache; |
| 2100 | |
| 2101 | /* If we are asked to unwind the PC, then we need to return the LR |
| 2102 | instead. The prologue may save PC, but it will point into this |
| 2103 | frame's prologue, not the next frame's resume location. Also |
| 2104 | strip the saved T bit. A valid LR may have the low bit set, but |
| 2105 | a valid PC never does. */ |
| 2106 | if (prev_regnum == ARM_PC_REGNUM) |
| 2107 | { |
| 2108 | CORE_ADDR lr; |
| 2109 | |
| 2110 | lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM); |
| 2111 | return frame_unwind_got_constant (this_frame, prev_regnum, |
| 2112 | arm_addr_bits_remove (gdbarch, lr)); |
| 2113 | } |
| 2114 | |
| 2115 | /* SP is generally not saved to the stack, but this frame is |
| 2116 | identified by the next frame's stack pointer at the time of the call. |
| 2117 | The value was already reconstructed into PREV_SP. */ |
| 2118 | if (prev_regnum == ARM_SP_REGNUM) |
| 2119 | return frame_unwind_got_constant (this_frame, prev_regnum, cache->prev_sp); |
| 2120 | |
| 2121 | /* The CPSR may have been changed by the call instruction and by the |
| 2122 | called function. The only bit we can reconstruct is the T bit, |
| 2123 | by checking the low bit of LR as of the call. This is a reliable |
| 2124 | indicator of Thumb-ness except for some ARM v4T pre-interworking |
| 2125 | Thumb code, which could get away with a clear low bit as long as |
| 2126 | the called function did not use bx. Guess that all other |
| 2127 | bits are unchanged; the condition flags are presumably lost, |
| 2128 | but the processor status is likely valid. */ |
| 2129 | if (prev_regnum == ARM_PS_REGNUM) |
| 2130 | { |
| 2131 | CORE_ADDR lr, cpsr; |
| 2132 | ULONGEST t_bit = arm_psr_thumb_bit (gdbarch); |
| 2133 | |
| 2134 | cpsr = get_frame_register_unsigned (this_frame, prev_regnum); |
| 2135 | lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM); |
| 2136 | if (IS_THUMB_ADDR (lr)) |
| 2137 | cpsr |= t_bit; |
| 2138 | else |
| 2139 | cpsr &= ~t_bit; |
| 2140 | return frame_unwind_got_constant (this_frame, prev_regnum, cpsr); |
| 2141 | } |
| 2142 | |
| 2143 | return trad_frame_get_prev_register (this_frame, cache->saved_regs, |
| 2144 | prev_regnum); |
| 2145 | } |
| 2146 | |
| 2147 | struct frame_unwind arm_prologue_unwind = { |
| 2148 | NORMAL_FRAME, |
| 2149 | arm_prologue_this_id, |
| 2150 | arm_prologue_prev_register, |
| 2151 | NULL, |
| 2152 | default_frame_sniffer |
| 2153 | }; |
| 2154 | |
| 2155 | /* Maintain a list of ARM exception table entries per objfile, similar to the |
| 2156 | list of mapping symbols. We only cache entries for standard ARM-defined |
| 2157 | personality routines; the cache will contain only the frame unwinding |
| 2158 | instructions associated with the entry (not the descriptors). */ |
| 2159 | |
| 2160 | static const struct objfile_data *arm_exidx_data_key; |
| 2161 | |
| 2162 | struct arm_exidx_entry |
| 2163 | { |
| 2164 | bfd_vma addr; |
| 2165 | gdb_byte *entry; |
| 2166 | }; |
| 2167 | typedef struct arm_exidx_entry arm_exidx_entry_s; |
| 2168 | DEF_VEC_O(arm_exidx_entry_s); |
| 2169 | |
| 2170 | struct arm_exidx_data |
| 2171 | { |
| 2172 | VEC(arm_exidx_entry_s) **section_maps; |
| 2173 | }; |
| 2174 | |
| 2175 | static void |
| 2176 | arm_exidx_data_free (struct objfile *objfile, void *arg) |
| 2177 | { |
| 2178 | struct arm_exidx_data *data = arg; |
| 2179 | unsigned int i; |
| 2180 | |
| 2181 | for (i = 0; i < objfile->obfd->section_count; i++) |
| 2182 | VEC_free (arm_exidx_entry_s, data->section_maps[i]); |
| 2183 | } |
| 2184 | |
| 2185 | static inline int |
| 2186 | arm_compare_exidx_entries (const struct arm_exidx_entry *lhs, |
| 2187 | const struct arm_exidx_entry *rhs) |
| 2188 | { |
| 2189 | return lhs->addr < rhs->addr; |
| 2190 | } |
| 2191 | |
| 2192 | static struct obj_section * |
| 2193 | arm_obj_section_from_vma (struct objfile *objfile, bfd_vma vma) |
| 2194 | { |
| 2195 | struct obj_section *osect; |
| 2196 | |
| 2197 | ALL_OBJFILE_OSECTIONS (objfile, osect) |
| 2198 | if (bfd_get_section_flags (objfile->obfd, |
| 2199 | osect->the_bfd_section) & SEC_ALLOC) |
| 2200 | { |
| 2201 | bfd_vma start, size; |
| 2202 | start = bfd_get_section_vma (objfile->obfd, osect->the_bfd_section); |
| 2203 | size = bfd_get_section_size (osect->the_bfd_section); |
| 2204 | |
| 2205 | if (start <= vma && vma < start + size) |
| 2206 | return osect; |
| 2207 | } |
| 2208 | |
| 2209 | return NULL; |
| 2210 | } |
| 2211 | |
| 2212 | /* Parse contents of exception table and exception index sections |
| 2213 | of OBJFILE, and fill in the exception table entry cache. |
| 2214 | |
| 2215 | For each entry that refers to a standard ARM-defined personality |
| 2216 | routine, extract the frame unwinding instructions (from either |
| 2217 | the index or the table section). The unwinding instructions |
| 2218 | are normalized by: |
| 2219 | - extracting them from the rest of the table data |
| 2220 | - converting to host endianness |
| 2221 | - appending the implicit 0xb0 ("Finish") code |
| 2222 | |
| 2223 | The extracted and normalized instructions are stored for later |
| 2224 | retrieval by the arm_find_exidx_entry routine. */ |
| 2225 | |
| 2226 | static void |
| 2227 | arm_exidx_new_objfile (struct objfile *objfile) |
| 2228 | { |
| 2229 | struct cleanup *cleanups = make_cleanup (null_cleanup, NULL); |
| 2230 | struct arm_exidx_data *data; |
| 2231 | asection *exidx, *extab; |
| 2232 | bfd_vma exidx_vma = 0, extab_vma = 0; |
| 2233 | bfd_size_type exidx_size = 0, extab_size = 0; |
| 2234 | gdb_byte *exidx_data = NULL, *extab_data = NULL; |
| 2235 | LONGEST i; |
| 2236 | |
| 2237 | /* If we've already touched this file, do nothing. */ |
| 2238 | if (!objfile || objfile_data (objfile, arm_exidx_data_key) != NULL) |
| 2239 | return; |
| 2240 | |
| 2241 | /* Read contents of exception table and index. */ |
| 2242 | exidx = bfd_get_section_by_name (objfile->obfd, ".ARM.exidx"); |
| 2243 | if (exidx) |
| 2244 | { |
| 2245 | exidx_vma = bfd_section_vma (objfile->obfd, exidx); |
| 2246 | exidx_size = bfd_get_section_size (exidx); |
| 2247 | exidx_data = xmalloc (exidx_size); |
| 2248 | make_cleanup (xfree, exidx_data); |
| 2249 | |
| 2250 | if (!bfd_get_section_contents (objfile->obfd, exidx, |
| 2251 | exidx_data, 0, exidx_size)) |
| 2252 | { |
| 2253 | do_cleanups (cleanups); |
| 2254 | return; |
| 2255 | } |
| 2256 | } |
| 2257 | |
| 2258 | extab = bfd_get_section_by_name (objfile->obfd, ".ARM.extab"); |
| 2259 | if (extab) |
| 2260 | { |
| 2261 | extab_vma = bfd_section_vma (objfile->obfd, extab); |
| 2262 | extab_size = bfd_get_section_size (extab); |
| 2263 | extab_data = xmalloc (extab_size); |
| 2264 | make_cleanup (xfree, extab_data); |
| 2265 | |
| 2266 | if (!bfd_get_section_contents (objfile->obfd, extab, |
| 2267 | extab_data, 0, extab_size)) |
| 2268 | { |
| 2269 | do_cleanups (cleanups); |
| 2270 | return; |
| 2271 | } |
| 2272 | } |
| 2273 | |
| 2274 | /* Allocate exception table data structure. */ |
| 2275 | data = OBSTACK_ZALLOC (&objfile->objfile_obstack, struct arm_exidx_data); |
| 2276 | set_objfile_data (objfile, arm_exidx_data_key, data); |
| 2277 | data->section_maps = OBSTACK_CALLOC (&objfile->objfile_obstack, |
| 2278 | objfile->obfd->section_count, |
| 2279 | VEC(arm_exidx_entry_s) *); |
| 2280 | |
| 2281 | /* Fill in exception table. */ |
| 2282 | for (i = 0; i < exidx_size / 8; i++) |
| 2283 | { |
| 2284 | struct arm_exidx_entry new_exidx_entry; |
| 2285 | bfd_vma idx = bfd_h_get_32 (objfile->obfd, exidx_data + i * 8); |
| 2286 | bfd_vma val = bfd_h_get_32 (objfile->obfd, exidx_data + i * 8 + 4); |
| 2287 | bfd_vma addr = 0, word = 0; |
| 2288 | int n_bytes = 0, n_words = 0; |
| 2289 | struct obj_section *sec; |
| 2290 | gdb_byte *entry = NULL; |
| 2291 | |
| 2292 | /* Extract address of start of function. */ |
| 2293 | idx = ((idx & 0x7fffffff) ^ 0x40000000) - 0x40000000; |
| 2294 | idx += exidx_vma + i * 8; |
| 2295 | |
| 2296 | /* Find section containing function and compute section offset. */ |
| 2297 | sec = arm_obj_section_from_vma (objfile, idx); |
| 2298 | if (sec == NULL) |
| 2299 | continue; |
| 2300 | idx -= bfd_get_section_vma (objfile->obfd, sec->the_bfd_section); |
| 2301 | |
| 2302 | /* Determine address of exception table entry. */ |
| 2303 | if (val == 1) |
| 2304 | { |
| 2305 | /* EXIDX_CANTUNWIND -- no exception table entry present. */ |
| 2306 | } |
| 2307 | else if ((val & 0xff000000) == 0x80000000) |
| 2308 | { |
| 2309 | /* Exception table entry embedded in .ARM.exidx |
| 2310 | -- must be short form. */ |
| 2311 | word = val; |
| 2312 | n_bytes = 3; |
| 2313 | } |
| 2314 | else if (!(val & 0x80000000)) |
| 2315 | { |
| 2316 | /* Exception table entry in .ARM.extab. */ |
| 2317 | addr = ((val & 0x7fffffff) ^ 0x40000000) - 0x40000000; |
| 2318 | addr += exidx_vma + i * 8 + 4; |
| 2319 | |
| 2320 | if (addr >= extab_vma && addr + 4 <= extab_vma + extab_size) |
| 2321 | { |
| 2322 | word = bfd_h_get_32 (objfile->obfd, |
| 2323 | extab_data + addr - extab_vma); |
| 2324 | addr += 4; |
| 2325 | |
| 2326 | if ((word & 0xff000000) == 0x80000000) |
| 2327 | { |
| 2328 | /* Short form. */ |
| 2329 | n_bytes = 3; |
| 2330 | } |
| 2331 | else if ((word & 0xff000000) == 0x81000000 |
| 2332 | || (word & 0xff000000) == 0x82000000) |
| 2333 | { |
| 2334 | /* Long form. */ |
| 2335 | n_bytes = 2; |
| 2336 | n_words = ((word >> 16) & 0xff); |
| 2337 | } |
| 2338 | else if (!(word & 0x80000000)) |
| 2339 | { |
| 2340 | bfd_vma pers; |
| 2341 | struct obj_section *pers_sec; |
| 2342 | int gnu_personality = 0; |
| 2343 | |
| 2344 | /* Custom personality routine. */ |
| 2345 | pers = ((word & 0x7fffffff) ^ 0x40000000) - 0x40000000; |
| 2346 | pers = UNMAKE_THUMB_ADDR (pers + addr - 4); |
| 2347 | |
| 2348 | /* Check whether we've got one of the variants of the |
| 2349 | GNU personality routines. */ |
| 2350 | pers_sec = arm_obj_section_from_vma (objfile, pers); |
| 2351 | if (pers_sec) |
| 2352 | { |
| 2353 | static const char *personality[] = |
| 2354 | { |
| 2355 | "__gcc_personality_v0", |
| 2356 | "__gxx_personality_v0", |
| 2357 | "__gcj_personality_v0", |
| 2358 | "__gnu_objc_personality_v0", |
| 2359 | NULL |
| 2360 | }; |
| 2361 | |
| 2362 | CORE_ADDR pc = pers + obj_section_offset (pers_sec); |
| 2363 | int k; |
| 2364 | |
| 2365 | for (k = 0; personality[k]; k++) |
| 2366 | if (lookup_minimal_symbol_by_pc_name |
| 2367 | (pc, personality[k], objfile)) |
| 2368 | { |
| 2369 | gnu_personality = 1; |
| 2370 | break; |
| 2371 | } |
| 2372 | } |
| 2373 | |
| 2374 | /* If so, the next word contains a word count in the high |
| 2375 | byte, followed by the same unwind instructions as the |
| 2376 | pre-defined forms. */ |
| 2377 | if (gnu_personality |
| 2378 | && addr + 4 <= extab_vma + extab_size) |
| 2379 | { |
| 2380 | word = bfd_h_get_32 (objfile->obfd, |
| 2381 | extab_data + addr - extab_vma); |
| 2382 | addr += 4; |
| 2383 | n_bytes = 3; |
| 2384 | n_words = ((word >> 24) & 0xff); |
| 2385 | } |
| 2386 | } |
| 2387 | } |
| 2388 | } |
| 2389 | |
| 2390 | /* Sanity check address. */ |
| 2391 | if (n_words) |
| 2392 | if (addr < extab_vma || addr + 4 * n_words > extab_vma + extab_size) |
| 2393 | n_words = n_bytes = 0; |
| 2394 | |
| 2395 | /* The unwind instructions reside in WORD (only the N_BYTES least |
| 2396 | significant bytes are valid), followed by N_WORDS words in the |
| 2397 | extab section starting at ADDR. */ |
| 2398 | if (n_bytes || n_words) |
| 2399 | { |
| 2400 | gdb_byte *p = entry = obstack_alloc (&objfile->objfile_obstack, |
| 2401 | n_bytes + n_words * 4 + 1); |
| 2402 | |
| 2403 | while (n_bytes--) |
| 2404 | *p++ = (gdb_byte) ((word >> (8 * n_bytes)) & 0xff); |
| 2405 | |
| 2406 | while (n_words--) |
| 2407 | { |
| 2408 | word = bfd_h_get_32 (objfile->obfd, |
| 2409 | extab_data + addr - extab_vma); |
| 2410 | addr += 4; |
| 2411 | |
| 2412 | *p++ = (gdb_byte) ((word >> 24) & 0xff); |
| 2413 | *p++ = (gdb_byte) ((word >> 16) & 0xff); |
| 2414 | *p++ = (gdb_byte) ((word >> 8) & 0xff); |
| 2415 | *p++ = (gdb_byte) (word & 0xff); |
| 2416 | } |
| 2417 | |
| 2418 | /* Implied "Finish" to terminate the list. */ |
| 2419 | *p++ = 0xb0; |
| 2420 | } |
| 2421 | |
| 2422 | /* Push entry onto vector. They are guaranteed to always |
| 2423 | appear in order of increasing addresses. */ |
| 2424 | new_exidx_entry.addr = idx; |
| 2425 | new_exidx_entry.entry = entry; |
| 2426 | VEC_safe_push (arm_exidx_entry_s, |
| 2427 | data->section_maps[sec->the_bfd_section->index], |
| 2428 | &new_exidx_entry); |
| 2429 | } |
| 2430 | |
| 2431 | do_cleanups (cleanups); |
| 2432 | } |
| 2433 | |
| 2434 | /* Search for the exception table entry covering MEMADDR. If one is found, |
| 2435 | return a pointer to its data. Otherwise, return 0. If START is non-NULL, |
| 2436 | set *START to the start of the region covered by this entry. */ |
| 2437 | |
| 2438 | static gdb_byte * |
| 2439 | arm_find_exidx_entry (CORE_ADDR memaddr, CORE_ADDR *start) |
| 2440 | { |
| 2441 | struct obj_section *sec; |
| 2442 | |
| 2443 | sec = find_pc_section (memaddr); |
| 2444 | if (sec != NULL) |
| 2445 | { |
| 2446 | struct arm_exidx_data *data; |
| 2447 | VEC(arm_exidx_entry_s) *map; |
| 2448 | struct arm_exidx_entry map_key = { memaddr - obj_section_addr (sec), 0 }; |
| 2449 | unsigned int idx; |
| 2450 | |
| 2451 | data = objfile_data (sec->objfile, arm_exidx_data_key); |
| 2452 | if (data != NULL) |
| 2453 | { |
| 2454 | map = data->section_maps[sec->the_bfd_section->index]; |
| 2455 | if (!VEC_empty (arm_exidx_entry_s, map)) |
| 2456 | { |
| 2457 | struct arm_exidx_entry *map_sym; |
| 2458 | |
| 2459 | idx = VEC_lower_bound (arm_exidx_entry_s, map, &map_key, |
| 2460 | arm_compare_exidx_entries); |
| 2461 | |
| 2462 | /* VEC_lower_bound finds the earliest ordered insertion |
| 2463 | point. If the following symbol starts at this exact |
| 2464 | address, we use that; otherwise, the preceding |
| 2465 | exception table entry covers this address. */ |
| 2466 | if (idx < VEC_length (arm_exidx_entry_s, map)) |
| 2467 | { |
| 2468 | map_sym = VEC_index (arm_exidx_entry_s, map, idx); |
| 2469 | if (map_sym->addr == map_key.addr) |
| 2470 | { |
| 2471 | if (start) |
| 2472 | *start = map_sym->addr + obj_section_addr (sec); |
| 2473 | return map_sym->entry; |
| 2474 | } |
| 2475 | } |
| 2476 | |
| 2477 | if (idx > 0) |
| 2478 | { |
| 2479 | map_sym = VEC_index (arm_exidx_entry_s, map, idx - 1); |
| 2480 | if (start) |
| 2481 | *start = map_sym->addr + obj_section_addr (sec); |
| 2482 | return map_sym->entry; |
| 2483 | } |
| 2484 | } |
| 2485 | } |
| 2486 | } |
| 2487 | |
| 2488 | return NULL; |
| 2489 | } |
| 2490 | |
| 2491 | /* Given the current frame THIS_FRAME, and its associated frame unwinding |
| 2492 | instruction list from the ARM exception table entry ENTRY, allocate and |
| 2493 | return a prologue cache structure describing how to unwind this frame. |
| 2494 | |
| 2495 | Return NULL if the unwinding instruction list contains a "spare", |
| 2496 | "reserved" or "refuse to unwind" instruction as defined in section |
| 2497 | "9.3 Frame unwinding instructions" of the "Exception Handling ABI |
| 2498 | for the ARM Architecture" document. */ |
| 2499 | |
| 2500 | static struct arm_prologue_cache * |
| 2501 | arm_exidx_fill_cache (struct frame_info *this_frame, gdb_byte *entry) |
| 2502 | { |
| 2503 | CORE_ADDR vsp = 0; |
| 2504 | int vsp_valid = 0; |
| 2505 | |
| 2506 | struct arm_prologue_cache *cache; |
| 2507 | cache = FRAME_OBSTACK_ZALLOC (struct arm_prologue_cache); |
| 2508 | cache->saved_regs = trad_frame_alloc_saved_regs (this_frame); |
| 2509 | |
| 2510 | for (;;) |
| 2511 | { |
| 2512 | gdb_byte insn; |
| 2513 | |
| 2514 | /* Whenever we reload SP, we actually have to retrieve its |
| 2515 | actual value in the current frame. */ |
| 2516 | if (!vsp_valid) |
| 2517 | { |
| 2518 | if (trad_frame_realreg_p (cache->saved_regs, ARM_SP_REGNUM)) |
| 2519 | { |
| 2520 | int reg = cache->saved_regs[ARM_SP_REGNUM].realreg; |
| 2521 | vsp = get_frame_register_unsigned (this_frame, reg); |
| 2522 | } |
| 2523 | else |
| 2524 | { |
| 2525 | CORE_ADDR addr = cache->saved_regs[ARM_SP_REGNUM].addr; |
| 2526 | vsp = get_frame_memory_unsigned (this_frame, addr, 4); |
| 2527 | } |
| 2528 | |
| 2529 | vsp_valid = 1; |
| 2530 | } |
| 2531 | |
| 2532 | /* Decode next unwind instruction. */ |
| 2533 | insn = *entry++; |
| 2534 | |
| 2535 | if ((insn & 0xc0) == 0) |
| 2536 | { |
| 2537 | int offset = insn & 0x3f; |
| 2538 | vsp += (offset << 2) + 4; |
| 2539 | } |
| 2540 | else if ((insn & 0xc0) == 0x40) |
| 2541 | { |
| 2542 | int offset = insn & 0x3f; |
| 2543 | vsp -= (offset << 2) + 4; |
| 2544 | } |
| 2545 | else if ((insn & 0xf0) == 0x80) |
| 2546 | { |
| 2547 | int mask = ((insn & 0xf) << 8) | *entry++; |
| 2548 | int i; |
| 2549 | |
| 2550 | /* The special case of an all-zero mask identifies |
| 2551 | "Refuse to unwind". We return NULL to fall back |
| 2552 | to the prologue analyzer. */ |
| 2553 | if (mask == 0) |
| 2554 | return NULL; |
| 2555 | |
| 2556 | /* Pop registers r4..r15 under mask. */ |
| 2557 | for (i = 0; i < 12; i++) |
| 2558 | if (mask & (1 << i)) |
| 2559 | { |
| 2560 | cache->saved_regs[4 + i].addr = vsp; |
| 2561 | vsp += 4; |
| 2562 | } |
| 2563 | |
| 2564 | /* Special-case popping SP -- we need to reload vsp. */ |
| 2565 | if (mask & (1 << (ARM_SP_REGNUM - 4))) |
| 2566 | vsp_valid = 0; |
| 2567 | } |
| 2568 | else if ((insn & 0xf0) == 0x90) |
| 2569 | { |
| 2570 | int reg = insn & 0xf; |
| 2571 | |
| 2572 | /* Reserved cases. */ |
| 2573 | if (reg == ARM_SP_REGNUM || reg == ARM_PC_REGNUM) |
| 2574 | return NULL; |
| 2575 | |
| 2576 | /* Set SP from another register and mark VSP for reload. */ |
| 2577 | cache->saved_regs[ARM_SP_REGNUM] = cache->saved_regs[reg]; |
| 2578 | vsp_valid = 0; |
| 2579 | } |
| 2580 | else if ((insn & 0xf0) == 0xa0) |
| 2581 | { |
| 2582 | int count = insn & 0x7; |
| 2583 | int pop_lr = (insn & 0x8) != 0; |
| 2584 | int i; |
| 2585 | |
| 2586 | /* Pop r4..r[4+count]. */ |
| 2587 | for (i = 0; i <= count; i++) |
| 2588 | { |
| 2589 | cache->saved_regs[4 + i].addr = vsp; |
| 2590 | vsp += 4; |
| 2591 | } |
| 2592 | |
| 2593 | /* If indicated by flag, pop LR as well. */ |
| 2594 | if (pop_lr) |
| 2595 | { |
| 2596 | cache->saved_regs[ARM_LR_REGNUM].addr = vsp; |
| 2597 | vsp += 4; |
| 2598 | } |
| 2599 | } |
| 2600 | else if (insn == 0xb0) |
| 2601 | { |
| 2602 | /* We could only have updated PC by popping into it; if so, it |
| 2603 | will show up as address. Otherwise, copy LR into PC. */ |
| 2604 | if (!trad_frame_addr_p (cache->saved_regs, ARM_PC_REGNUM)) |
| 2605 | cache->saved_regs[ARM_PC_REGNUM] |
| 2606 | = cache->saved_regs[ARM_LR_REGNUM]; |
| 2607 | |
| 2608 | /* We're done. */ |
| 2609 | break; |
| 2610 | } |
| 2611 | else if (insn == 0xb1) |
| 2612 | { |
| 2613 | int mask = *entry++; |
| 2614 | int i; |
| 2615 | |
| 2616 | /* All-zero mask and mask >= 16 is "spare". */ |
| 2617 | if (mask == 0 || mask >= 16) |
| 2618 | return NULL; |
| 2619 | |
| 2620 | /* Pop r0..r3 under mask. */ |
| 2621 | for (i = 0; i < 4; i++) |
| 2622 | if (mask & (1 << i)) |
| 2623 | { |
| 2624 | cache->saved_regs[i].addr = vsp; |
| 2625 | vsp += 4; |
| 2626 | } |
| 2627 | } |
| 2628 | else if (insn == 0xb2) |
| 2629 | { |
| 2630 | ULONGEST offset = 0; |
| 2631 | unsigned shift = 0; |
| 2632 | |
| 2633 | do |
| 2634 | { |
| 2635 | offset |= (*entry & 0x7f) << shift; |
| 2636 | shift += 7; |
| 2637 | } |
| 2638 | while (*entry++ & 0x80); |
| 2639 | |
| 2640 | vsp += 0x204 + (offset << 2); |
| 2641 | } |
| 2642 | else if (insn == 0xb3) |
| 2643 | { |
| 2644 | int start = *entry >> 4; |
| 2645 | int count = (*entry++) & 0xf; |
| 2646 | int i; |
| 2647 | |
| 2648 | /* Only registers D0..D15 are valid here. */ |
| 2649 | if (start + count >= 16) |
| 2650 | return NULL; |
| 2651 | |
| 2652 | /* Pop VFP double-precision registers D[start]..D[start+count]. */ |
| 2653 | for (i = 0; i <= count; i++) |
| 2654 | { |
| 2655 | cache->saved_regs[ARM_D0_REGNUM + start + i].addr = vsp; |
| 2656 | vsp += 8; |
| 2657 | } |
| 2658 | |
| 2659 | /* Add an extra 4 bytes for FSTMFDX-style stack. */ |
| 2660 | vsp += 4; |
| 2661 | } |
| 2662 | else if ((insn & 0xf8) == 0xb8) |
| 2663 | { |
| 2664 | int count = insn & 0x7; |
| 2665 | int i; |
| 2666 | |
| 2667 | /* Pop VFP double-precision registers D[8]..D[8+count]. */ |
| 2668 | for (i = 0; i <= count; i++) |
| 2669 | { |
| 2670 | cache->saved_regs[ARM_D0_REGNUM + 8 + i].addr = vsp; |
| 2671 | vsp += 8; |
| 2672 | } |
| 2673 | |
| 2674 | /* Add an extra 4 bytes for FSTMFDX-style stack. */ |
| 2675 | vsp += 4; |
| 2676 | } |
| 2677 | else if (insn == 0xc6) |
| 2678 | { |
| 2679 | int start = *entry >> 4; |
| 2680 | int count = (*entry++) & 0xf; |
| 2681 | int i; |
| 2682 | |
| 2683 | /* Only registers WR0..WR15 are valid. */ |
| 2684 | if (start + count >= 16) |
| 2685 | return NULL; |
| 2686 | |
| 2687 | /* Pop iwmmx registers WR[start]..WR[start+count]. */ |
| 2688 | for (i = 0; i <= count; i++) |
| 2689 | { |
| 2690 | cache->saved_regs[ARM_WR0_REGNUM + start + i].addr = vsp; |
| 2691 | vsp += 8; |
| 2692 | } |
| 2693 | } |
| 2694 | else if (insn == 0xc7) |
| 2695 | { |
| 2696 | int mask = *entry++; |
| 2697 | int i; |
| 2698 | |
| 2699 | /* All-zero mask and mask >= 16 is "spare". */ |
| 2700 | if (mask == 0 || mask >= 16) |
| 2701 | return NULL; |
| 2702 | |
| 2703 | /* Pop iwmmx general-purpose registers WCGR0..WCGR3 under mask. */ |
| 2704 | for (i = 0; i < 4; i++) |
| 2705 | if (mask & (1 << i)) |
| 2706 | { |
| 2707 | cache->saved_regs[ARM_WCGR0_REGNUM + i].addr = vsp; |
| 2708 | vsp += 4; |
| 2709 | } |
| 2710 | } |
| 2711 | else if ((insn & 0xf8) == 0xc0) |
| 2712 | { |
| 2713 | int count = insn & 0x7; |
| 2714 | int i; |
| 2715 | |
| 2716 | /* Pop iwmmx registers WR[10]..WR[10+count]. */ |
| 2717 | for (i = 0; i <= count; i++) |
| 2718 | { |
| 2719 | cache->saved_regs[ARM_WR0_REGNUM + 10 + i].addr = vsp; |
| 2720 | vsp += 8; |
| 2721 | } |
| 2722 | } |
| 2723 | else if (insn == 0xc8) |
| 2724 | { |
| 2725 | int start = *entry >> 4; |
| 2726 | int count = (*entry++) & 0xf; |
| 2727 | int i; |
| 2728 | |
| 2729 | /* Only registers D0..D31 are valid. */ |
| 2730 | if (start + count >= 16) |
| 2731 | return NULL; |
| 2732 | |
| 2733 | /* Pop VFP double-precision registers |
| 2734 | D[16+start]..D[16+start+count]. */ |
| 2735 | for (i = 0; i <= count; i++) |
| 2736 | { |
| 2737 | cache->saved_regs[ARM_D0_REGNUM + 16 + start + i].addr = vsp; |
| 2738 | vsp += 8; |
| 2739 | } |
| 2740 | } |
| 2741 | else if (insn == 0xc9) |
| 2742 | { |
| 2743 | int start = *entry >> 4; |
| 2744 | int count = (*entry++) & 0xf; |
| 2745 | int i; |
| 2746 | |
| 2747 | /* Pop VFP double-precision registers D[start]..D[start+count]. */ |
| 2748 | for (i = 0; i <= count; i++) |
| 2749 | { |
| 2750 | cache->saved_regs[ARM_D0_REGNUM + start + i].addr = vsp; |
| 2751 | vsp += 8; |
| 2752 | } |
| 2753 | } |
| 2754 | else if ((insn & 0xf8) == 0xd0) |
| 2755 | { |
| 2756 | int count = insn & 0x7; |
| 2757 | int i; |
| 2758 | |
| 2759 | /* Pop VFP double-precision registers D[8]..D[8+count]. */ |
| 2760 | for (i = 0; i <= count; i++) |
| 2761 | { |
| 2762 | cache->saved_regs[ARM_D0_REGNUM + 8 + i].addr = vsp; |
| 2763 | vsp += 8; |
| 2764 | } |
| 2765 | } |
| 2766 | else |
| 2767 | { |
| 2768 | /* Everything else is "spare". */ |
| 2769 | return NULL; |
| 2770 | } |
| 2771 | } |
| 2772 | |
| 2773 | /* If we restore SP from a register, assume this was the frame register. |
| 2774 | Otherwise just fall back to SP as frame register. */ |
| 2775 | if (trad_frame_realreg_p (cache->saved_regs, ARM_SP_REGNUM)) |
| 2776 | cache->framereg = cache->saved_regs[ARM_SP_REGNUM].realreg; |
| 2777 | else |
| 2778 | cache->framereg = ARM_SP_REGNUM; |
| 2779 | |
| 2780 | /* Determine offset to previous frame. */ |
| 2781 | cache->framesize |
| 2782 | = vsp - get_frame_register_unsigned (this_frame, cache->framereg); |
| 2783 | |
| 2784 | /* We already got the previous SP. */ |
| 2785 | cache->prev_sp = vsp; |
| 2786 | |
| 2787 | return cache; |
| 2788 | } |
| 2789 | |
| 2790 | /* Unwinding via ARM exception table entries. Note that the sniffer |
| 2791 | already computes a filled-in prologue cache, which is then used |
| 2792 | with the same arm_prologue_this_id and arm_prologue_prev_register |
| 2793 | routines also used for prologue-parsing based unwinding. */ |
| 2794 | |
| 2795 | static int |
| 2796 | arm_exidx_unwind_sniffer (const struct frame_unwind *self, |
| 2797 | struct frame_info *this_frame, |
| 2798 | void **this_prologue_cache) |
| 2799 | { |
| 2800 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| 2801 | enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch); |
| 2802 | CORE_ADDR addr_in_block, exidx_region, func_start; |
| 2803 | struct arm_prologue_cache *cache; |
| 2804 | gdb_byte *entry; |
| 2805 | |
| 2806 | /* See if we have an ARM exception table entry covering this address. */ |
| 2807 | addr_in_block = get_frame_address_in_block (this_frame); |
| 2808 | entry = arm_find_exidx_entry (addr_in_block, &exidx_region); |
| 2809 | if (!entry) |
| 2810 | return 0; |
| 2811 | |
| 2812 | /* The ARM exception table does not describe unwind information |
| 2813 | for arbitrary PC values, but is guaranteed to be correct only |
| 2814 | at call sites. We have to decide here whether we want to use |
| 2815 | ARM exception table information for this frame, or fall back |
| 2816 | to using prologue parsing. (Note that if we have DWARF CFI, |
| 2817 | this sniffer isn't even called -- CFI is always preferred.) |
| 2818 | |
| 2819 | Before we make this decision, however, we check whether we |
| 2820 | actually have *symbol* information for the current frame. |
| 2821 | If not, prologue parsing would not work anyway, so we might |
| 2822 | as well use the exception table and hope for the best. */ |
| 2823 | if (find_pc_partial_function (addr_in_block, NULL, &func_start, NULL)) |
| 2824 | { |
| 2825 | int exc_valid = 0; |
| 2826 | |
| 2827 | /* If the next frame is "normal", we are at a call site in this |
| 2828 | frame, so exception information is guaranteed to be valid. */ |
| 2829 | if (get_next_frame (this_frame) |
| 2830 | && get_frame_type (get_next_frame (this_frame)) == NORMAL_FRAME) |
| 2831 | exc_valid = 1; |
| 2832 | |
| 2833 | /* We also assume exception information is valid if we're currently |
| 2834 | blocked in a system call. The system library is supposed to |
| 2835 | ensure this, so that e.g. pthread cancellation works. */ |
| 2836 | if (arm_frame_is_thumb (this_frame)) |
| 2837 | { |
| 2838 | LONGEST insn; |
| 2839 | |
| 2840 | if (safe_read_memory_integer (get_frame_pc (this_frame) - 2, 2, |
| 2841 | byte_order_for_code, &insn) |
| 2842 | && (insn & 0xff00) == 0xdf00 /* svc */) |
| 2843 | exc_valid = 1; |
| 2844 | } |
| 2845 | else |
| 2846 | { |
| 2847 | LONGEST insn; |
| 2848 | |
| 2849 | if (safe_read_memory_integer (get_frame_pc (this_frame) - 4, 4, |
| 2850 | byte_order_for_code, &insn) |
| 2851 | && (insn & 0x0f000000) == 0x0f000000 /* svc */) |
| 2852 | exc_valid = 1; |
| 2853 | } |
| 2854 | |
| 2855 | /* Bail out if we don't know that exception information is valid. */ |
| 2856 | if (!exc_valid) |
| 2857 | return 0; |
| 2858 | |
| 2859 | /* The ARM exception index does not mark the *end* of the region |
| 2860 | covered by the entry, and some functions will not have any entry. |
| 2861 | To correctly recognize the end of the covered region, the linker |
| 2862 | should have inserted dummy records with a CANTUNWIND marker. |
| 2863 | |
| 2864 | Unfortunately, current versions of GNU ld do not reliably do |
| 2865 | this, and thus we may have found an incorrect entry above. |
| 2866 | As a (temporary) sanity check, we only use the entry if it |
| 2867 | lies *within* the bounds of the function. Note that this check |
| 2868 | might reject perfectly valid entries that just happen to cover |
| 2869 | multiple functions; therefore this check ought to be removed |
| 2870 | once the linker is fixed. */ |
| 2871 | if (func_start > exidx_region) |
| 2872 | return 0; |
| 2873 | } |
| 2874 | |
| 2875 | /* Decode the list of unwinding instructions into a prologue cache. |
| 2876 | Note that this may fail due to e.g. a "refuse to unwind" code. */ |
| 2877 | cache = arm_exidx_fill_cache (this_frame, entry); |
| 2878 | if (!cache) |
| 2879 | return 0; |
| 2880 | |
| 2881 | *this_prologue_cache = cache; |
| 2882 | return 1; |
| 2883 | } |
| 2884 | |
| 2885 | struct frame_unwind arm_exidx_unwind = { |
| 2886 | NORMAL_FRAME, |
| 2887 | arm_prologue_this_id, |
| 2888 | arm_prologue_prev_register, |
| 2889 | NULL, |
| 2890 | arm_exidx_unwind_sniffer |
| 2891 | }; |
| 2892 | |
| 2893 | static struct arm_prologue_cache * |
| 2894 | arm_make_stub_cache (struct frame_info *this_frame) |
| 2895 | { |
| 2896 | struct arm_prologue_cache *cache; |
| 2897 | |
| 2898 | cache = FRAME_OBSTACK_ZALLOC (struct arm_prologue_cache); |
| 2899 | cache->saved_regs = trad_frame_alloc_saved_regs (this_frame); |
| 2900 | |
| 2901 | cache->prev_sp = get_frame_register_unsigned (this_frame, ARM_SP_REGNUM); |
| 2902 | |
| 2903 | return cache; |
| 2904 | } |
| 2905 | |
| 2906 | /* Our frame ID for a stub frame is the current SP and LR. */ |
| 2907 | |
| 2908 | static void |
| 2909 | arm_stub_this_id (struct frame_info *this_frame, |
| 2910 | void **this_cache, |
| 2911 | struct frame_id *this_id) |
| 2912 | { |
| 2913 | struct arm_prologue_cache *cache; |
| 2914 | |
| 2915 | if (*this_cache == NULL) |
| 2916 | *this_cache = arm_make_stub_cache (this_frame); |
| 2917 | cache = *this_cache; |
| 2918 | |
| 2919 | *this_id = frame_id_build (cache->prev_sp, get_frame_pc (this_frame)); |
| 2920 | } |
| 2921 | |
| 2922 | static int |
| 2923 | arm_stub_unwind_sniffer (const struct frame_unwind *self, |
| 2924 | struct frame_info *this_frame, |
| 2925 | void **this_prologue_cache) |
| 2926 | { |
| 2927 | CORE_ADDR addr_in_block; |
| 2928 | char dummy[4]; |
| 2929 | |
| 2930 | addr_in_block = get_frame_address_in_block (this_frame); |
| 2931 | if (in_plt_section (addr_in_block, NULL) |
| 2932 | /* We also use the stub winder if the target memory is unreadable |
| 2933 | to avoid having the prologue unwinder trying to read it. */ |
| 2934 | || target_read_memory (get_frame_pc (this_frame), dummy, 4) != 0) |
| 2935 | return 1; |
| 2936 | |
| 2937 | return 0; |
| 2938 | } |
| 2939 | |
| 2940 | struct frame_unwind arm_stub_unwind = { |
| 2941 | NORMAL_FRAME, |
| 2942 | arm_stub_this_id, |
| 2943 | arm_prologue_prev_register, |
| 2944 | NULL, |
| 2945 | arm_stub_unwind_sniffer |
| 2946 | }; |
| 2947 | |
| 2948 | static CORE_ADDR |
| 2949 | arm_normal_frame_base (struct frame_info *this_frame, void **this_cache) |
| 2950 | { |
| 2951 | struct arm_prologue_cache *cache; |
| 2952 | |
| 2953 | if (*this_cache == NULL) |
| 2954 | *this_cache = arm_make_prologue_cache (this_frame); |
| 2955 | cache = *this_cache; |
| 2956 | |
| 2957 | return cache->prev_sp - cache->framesize; |
| 2958 | } |
| 2959 | |
| 2960 | struct frame_base arm_normal_base = { |
| 2961 | &arm_prologue_unwind, |
| 2962 | arm_normal_frame_base, |
| 2963 | arm_normal_frame_base, |
| 2964 | arm_normal_frame_base |
| 2965 | }; |
| 2966 | |
| 2967 | /* Assuming THIS_FRAME is a dummy, return the frame ID of that |
| 2968 | dummy frame. The frame ID's base needs to match the TOS value |
| 2969 | saved by save_dummy_frame_tos() and returned from |
| 2970 | arm_push_dummy_call, and the PC needs to match the dummy frame's |
| 2971 | breakpoint. */ |
| 2972 | |
| 2973 | static struct frame_id |
| 2974 | arm_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame) |
| 2975 | { |
| 2976 | return frame_id_build (get_frame_register_unsigned (this_frame, |
| 2977 | ARM_SP_REGNUM), |
| 2978 | get_frame_pc (this_frame)); |
| 2979 | } |
| 2980 | |
| 2981 | /* Given THIS_FRAME, find the previous frame's resume PC (which will |
| 2982 | be used to construct the previous frame's ID, after looking up the |
| 2983 | containing function). */ |
| 2984 | |
| 2985 | static CORE_ADDR |
| 2986 | arm_unwind_pc (struct gdbarch *gdbarch, struct frame_info *this_frame) |
| 2987 | { |
| 2988 | CORE_ADDR pc; |
| 2989 | pc = frame_unwind_register_unsigned (this_frame, ARM_PC_REGNUM); |
| 2990 | return arm_addr_bits_remove (gdbarch, pc); |
| 2991 | } |
| 2992 | |
| 2993 | static CORE_ADDR |
| 2994 | arm_unwind_sp (struct gdbarch *gdbarch, struct frame_info *this_frame) |
| 2995 | { |
| 2996 | return frame_unwind_register_unsigned (this_frame, ARM_SP_REGNUM); |
| 2997 | } |
| 2998 | |
| 2999 | static struct value * |
| 3000 | arm_dwarf2_prev_register (struct frame_info *this_frame, void **this_cache, |
| 3001 | int regnum) |
| 3002 | { |
| 3003 | struct gdbarch * gdbarch = get_frame_arch (this_frame); |
| 3004 | CORE_ADDR lr, cpsr; |
| 3005 | ULONGEST t_bit = arm_psr_thumb_bit (gdbarch); |
| 3006 | |
| 3007 | switch (regnum) |
| 3008 | { |
| 3009 | case ARM_PC_REGNUM: |
| 3010 | /* The PC is normally copied from the return column, which |
| 3011 | describes saves of LR. However, that version may have an |
| 3012 | extra bit set to indicate Thumb state. The bit is not |
| 3013 | part of the PC. */ |
| 3014 | lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM); |
| 3015 | return frame_unwind_got_constant (this_frame, regnum, |
| 3016 | arm_addr_bits_remove (gdbarch, lr)); |
| 3017 | |
| 3018 | case ARM_PS_REGNUM: |
| 3019 | /* Reconstruct the T bit; see arm_prologue_prev_register for details. */ |
| 3020 | cpsr = get_frame_register_unsigned (this_frame, regnum); |
| 3021 | lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM); |
| 3022 | if (IS_THUMB_ADDR (lr)) |
| 3023 | cpsr |= t_bit; |
| 3024 | else |
| 3025 | cpsr &= ~t_bit; |
| 3026 | return frame_unwind_got_constant (this_frame, regnum, cpsr); |
| 3027 | |
| 3028 | default: |
| 3029 | internal_error (__FILE__, __LINE__, |
| 3030 | _("Unexpected register %d"), regnum); |
| 3031 | } |
| 3032 | } |
| 3033 | |
| 3034 | static void |
| 3035 | arm_dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum, |
| 3036 | struct dwarf2_frame_state_reg *reg, |
| 3037 | struct frame_info *this_frame) |
| 3038 | { |
| 3039 | switch (regnum) |
| 3040 | { |
| 3041 | case ARM_PC_REGNUM: |
| 3042 | case ARM_PS_REGNUM: |
| 3043 | reg->how = DWARF2_FRAME_REG_FN; |
| 3044 | reg->loc.fn = arm_dwarf2_prev_register; |
| 3045 | break; |
| 3046 | case ARM_SP_REGNUM: |
| 3047 | reg->how = DWARF2_FRAME_REG_CFA; |
| 3048 | break; |
| 3049 | } |
| 3050 | } |
| 3051 | |
| 3052 | /* Return true if we are in the function's epilogue, i.e. after the |
| 3053 | instruction that destroyed the function's stack frame. */ |
| 3054 | |
| 3055 | static int |
| 3056 | thumb_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 3057 | { |
| 3058 | enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch); |
| 3059 | unsigned int insn, insn2; |
| 3060 | int found_return = 0, found_stack_adjust = 0; |
| 3061 | CORE_ADDR func_start, func_end; |
| 3062 | CORE_ADDR scan_pc; |
| 3063 | gdb_byte buf[4]; |
| 3064 | |
| 3065 | if (!find_pc_partial_function (pc, NULL, &func_start, &func_end)) |
| 3066 | return 0; |
| 3067 | |
| 3068 | /* The epilogue is a sequence of instructions along the following lines: |
| 3069 | |
| 3070 | - add stack frame size to SP or FP |
| 3071 | - [if frame pointer used] restore SP from FP |
| 3072 | - restore registers from SP [may include PC] |
| 3073 | - a return-type instruction [if PC wasn't already restored] |
| 3074 | |
| 3075 | In a first pass, we scan forward from the current PC and verify the |
| 3076 | instructions we find as compatible with this sequence, ending in a |
| 3077 | return instruction. |
| 3078 | |
| 3079 | However, this is not sufficient to distinguish indirect function calls |
| 3080 | within a function from indirect tail calls in the epilogue in some cases. |
| 3081 | Therefore, if we didn't already find any SP-changing instruction during |
| 3082 | forward scan, we add a backward scanning heuristic to ensure we actually |
| 3083 | are in the epilogue. */ |
| 3084 | |
| 3085 | scan_pc = pc; |
| 3086 | while (scan_pc < func_end && !found_return) |
| 3087 | { |
| 3088 | if (target_read_memory (scan_pc, buf, 2)) |
| 3089 | break; |
| 3090 | |
| 3091 | scan_pc += 2; |
| 3092 | insn = extract_unsigned_integer (buf, 2, byte_order_for_code); |
| 3093 | |
| 3094 | if ((insn & 0xff80) == 0x4700) /* bx <Rm> */ |
| 3095 | found_return = 1; |
| 3096 | else if (insn == 0x46f7) /* mov pc, lr */ |
| 3097 | found_return = 1; |
| 3098 | else if (insn == 0x46bd) /* mov sp, r7 */ |
| 3099 | found_stack_adjust = 1; |
| 3100 | else if ((insn & 0xff00) == 0xb000) /* add sp, imm or sub sp, imm */ |
| 3101 | found_stack_adjust = 1; |
| 3102 | else if ((insn & 0xfe00) == 0xbc00) /* pop <registers> */ |
| 3103 | { |
| 3104 | found_stack_adjust = 1; |
| 3105 | if (insn & 0x0100) /* <registers> include PC. */ |
| 3106 | found_return = 1; |
| 3107 | } |
| 3108 | else if ((insn & 0xe000) == 0xe000) /* 32-bit Thumb-2 instruction */ |
| 3109 | { |
| 3110 | if (target_read_memory (scan_pc, buf, 2)) |
| 3111 | break; |
| 3112 | |
| 3113 | scan_pc += 2; |
| 3114 | insn2 = extract_unsigned_integer (buf, 2, byte_order_for_code); |
| 3115 | |
| 3116 | if (insn == 0xe8bd) /* ldm.w sp!, <registers> */ |
| 3117 | { |
| 3118 | found_stack_adjust = 1; |
| 3119 | if (insn2 & 0x8000) /* <registers> include PC. */ |
| 3120 | found_return = 1; |
| 3121 | } |
| 3122 | else if (insn == 0xf85d /* ldr.w <Rt>, [sp], #4 */ |
| 3123 | && (insn2 & 0x0fff) == 0x0b04) |
| 3124 | { |
| 3125 | found_stack_adjust = 1; |
| 3126 | if ((insn2 & 0xf000) == 0xf000) /* <Rt> is PC. */ |
| 3127 | found_return = 1; |
| 3128 | } |
| 3129 | else if ((insn & 0xffbf) == 0xecbd /* vldm sp!, <list> */ |
| 3130 | && (insn2 & 0x0e00) == 0x0a00) |
| 3131 | found_stack_adjust = 1; |
| 3132 | else |
| 3133 | break; |
| 3134 | } |
| 3135 | else |
| 3136 | break; |
| 3137 | } |
| 3138 | |
| 3139 | if (!found_return) |
| 3140 | return 0; |
| 3141 | |
| 3142 | /* Since any instruction in the epilogue sequence, with the possible |
| 3143 | exception of return itself, updates the stack pointer, we need to |
| 3144 | scan backwards for at most one instruction. Try either a 16-bit or |
| 3145 | a 32-bit instruction. This is just a heuristic, so we do not worry |
| 3146 | too much about false positives. */ |
| 3147 | |
| 3148 | if (!found_stack_adjust) |
| 3149 | { |
| 3150 | if (pc - 4 < func_start) |
| 3151 | return 0; |
| 3152 | if (target_read_memory (pc - 4, buf, 4)) |
| 3153 | return 0; |
| 3154 | |
| 3155 | insn = extract_unsigned_integer (buf, 2, byte_order_for_code); |
| 3156 | insn2 = extract_unsigned_integer (buf + 2, 2, byte_order_for_code); |
| 3157 | |
| 3158 | if (insn2 == 0x46bd) /* mov sp, r7 */ |
| 3159 | found_stack_adjust = 1; |
| 3160 | else if ((insn2 & 0xff00) == 0xb000) /* add sp, imm or sub sp, imm */ |
| 3161 | found_stack_adjust = 1; |
| 3162 | else if ((insn2 & 0xff00) == 0xbc00) /* pop <registers> without PC */ |
| 3163 | found_stack_adjust = 1; |
| 3164 | else if (insn == 0xe8bd) /* ldm.w sp!, <registers> */ |
| 3165 | found_stack_adjust = 1; |
| 3166 | else if (insn == 0xf85d /* ldr.w <Rt>, [sp], #4 */ |
| 3167 | && (insn2 & 0x0fff) == 0x0b04) |
| 3168 | found_stack_adjust = 1; |
| 3169 | else if ((insn & 0xffbf) == 0xecbd /* vldm sp!, <list> */ |
| 3170 | && (insn2 & 0x0e00) == 0x0a00) |
| 3171 | found_stack_adjust = 1; |
| 3172 | } |
| 3173 | |
| 3174 | return found_stack_adjust; |
| 3175 | } |
| 3176 | |
| 3177 | /* Return true if we are in the function's epilogue, i.e. after the |
| 3178 | instruction that destroyed the function's stack frame. */ |
| 3179 | |
| 3180 | static int |
| 3181 | arm_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 3182 | { |
| 3183 | enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch); |
| 3184 | unsigned int insn; |
| 3185 | int found_return, found_stack_adjust; |
| 3186 | CORE_ADDR func_start, func_end; |
| 3187 | |
| 3188 | if (arm_pc_is_thumb (gdbarch, pc)) |
| 3189 | return thumb_in_function_epilogue_p (gdbarch, pc); |
| 3190 | |
| 3191 | if (!find_pc_partial_function (pc, NULL, &func_start, &func_end)) |
| 3192 | return 0; |
| 3193 | |
| 3194 | /* We are in the epilogue if the previous instruction was a stack |
| 3195 | adjustment and the next instruction is a possible return (bx, mov |
| 3196 | pc, or pop). We could have to scan backwards to find the stack |
| 3197 | adjustment, or forwards to find the return, but this is a decent |
| 3198 | approximation. First scan forwards. */ |
| 3199 | |
| 3200 | found_return = 0; |
| 3201 | insn = read_memory_unsigned_integer (pc, 4, byte_order_for_code); |
| 3202 | if (bits (insn, 28, 31) != INST_NV) |
| 3203 | { |
| 3204 | if ((insn & 0x0ffffff0) == 0x012fff10) |
| 3205 | /* BX. */ |
| 3206 | found_return = 1; |
| 3207 | else if ((insn & 0x0ffffff0) == 0x01a0f000) |
| 3208 | /* MOV PC. */ |
| 3209 | found_return = 1; |
| 3210 | else if ((insn & 0x0fff0000) == 0x08bd0000 |
| 3211 | && (insn & 0x0000c000) != 0) |
| 3212 | /* POP (LDMIA), including PC or LR. */ |
| 3213 | found_return = 1; |
| 3214 | } |
| 3215 | |
| 3216 | if (!found_return) |
| 3217 | return 0; |
| 3218 | |
| 3219 | /* Scan backwards. This is just a heuristic, so do not worry about |
| 3220 | false positives from mode changes. */ |
| 3221 | |
| 3222 | if (pc < func_start + 4) |
| 3223 | return 0; |
| 3224 | |
| 3225 | found_stack_adjust = 0; |
| 3226 | insn = read_memory_unsigned_integer (pc - 4, 4, byte_order_for_code); |
| 3227 | if (bits (insn, 28, 31) != INST_NV) |
| 3228 | { |
| 3229 | if ((insn & 0x0df0f000) == 0x0080d000) |
| 3230 | /* ADD SP (register or immediate). */ |
| 3231 | found_stack_adjust = 1; |
| 3232 | else if ((insn & 0x0df0f000) == 0x0040d000) |
| 3233 | /* SUB SP (register or immediate). */ |
| 3234 | found_stack_adjust = 1; |
| 3235 | else if ((insn & 0x0ffffff0) == 0x01a0d000) |
| 3236 | /* MOV SP. */ |
| 3237 | found_stack_adjust = 1; |
| 3238 | else if ((insn & 0x0fff0000) == 0x08bd0000) |
| 3239 | /* POP (LDMIA). */ |
| 3240 | found_stack_adjust = 1; |
| 3241 | } |
| 3242 | |
| 3243 | if (found_stack_adjust) |
| 3244 | return 1; |
| 3245 | |
| 3246 | return 0; |
| 3247 | } |
| 3248 | |
| 3249 | |
| 3250 | /* When arguments must be pushed onto the stack, they go on in reverse |
| 3251 | order. The code below implements a FILO (stack) to do this. */ |
| 3252 | |
| 3253 | struct stack_item |
| 3254 | { |
| 3255 | int len; |
| 3256 | struct stack_item *prev; |
| 3257 | void *data; |
| 3258 | }; |
| 3259 | |
| 3260 | static struct stack_item * |
| 3261 | push_stack_item (struct stack_item *prev, const void *contents, int len) |
| 3262 | { |
| 3263 | struct stack_item *si; |
| 3264 | si = xmalloc (sizeof (struct stack_item)); |
| 3265 | si->data = xmalloc (len); |
| 3266 | si->len = len; |
| 3267 | si->prev = prev; |
| 3268 | memcpy (si->data, contents, len); |
| 3269 | return si; |
| 3270 | } |
| 3271 | |
| 3272 | static struct stack_item * |
| 3273 | pop_stack_item (struct stack_item *si) |
| 3274 | { |
| 3275 | struct stack_item *dead = si; |
| 3276 | si = si->prev; |
| 3277 | xfree (dead->data); |
| 3278 | xfree (dead); |
| 3279 | return si; |
| 3280 | } |
| 3281 | |
| 3282 | |
| 3283 | /* Return the alignment (in bytes) of the given type. */ |
| 3284 | |
| 3285 | static int |
| 3286 | arm_type_align (struct type *t) |
| 3287 | { |
| 3288 | int n; |
| 3289 | int align; |
| 3290 | int falign; |
| 3291 | |
| 3292 | t = check_typedef (t); |
| 3293 | switch (TYPE_CODE (t)) |
| 3294 | { |
| 3295 | default: |
| 3296 | /* Should never happen. */ |
| 3297 | internal_error (__FILE__, __LINE__, _("unknown type alignment")); |
| 3298 | return 4; |
| 3299 | |
| 3300 | case TYPE_CODE_PTR: |
| 3301 | case TYPE_CODE_ENUM: |
| 3302 | case TYPE_CODE_INT: |
| 3303 | case TYPE_CODE_FLT: |
| 3304 | case TYPE_CODE_SET: |
| 3305 | case TYPE_CODE_RANGE: |
| 3306 | case TYPE_CODE_BITSTRING: |
| 3307 | case TYPE_CODE_REF: |
| 3308 | case TYPE_CODE_CHAR: |
| 3309 | case TYPE_CODE_BOOL: |
| 3310 | return TYPE_LENGTH (t); |
| 3311 | |
| 3312 | case TYPE_CODE_ARRAY: |
| 3313 | case TYPE_CODE_COMPLEX: |
| 3314 | /* TODO: What about vector types? */ |
| 3315 | return arm_type_align (TYPE_TARGET_TYPE (t)); |
| 3316 | |
| 3317 | case TYPE_CODE_STRUCT: |
| 3318 | case TYPE_CODE_UNION: |
| 3319 | align = 1; |
| 3320 | for (n = 0; n < TYPE_NFIELDS (t); n++) |
| 3321 | { |
| 3322 | falign = arm_type_align (TYPE_FIELD_TYPE (t, n)); |
| 3323 | if (falign > align) |
| 3324 | align = falign; |
| 3325 | } |
| 3326 | return align; |
| 3327 | } |
| 3328 | } |
| 3329 | |
| 3330 | /* Possible base types for a candidate for passing and returning in |
| 3331 | VFP registers. */ |
| 3332 | |
| 3333 | enum arm_vfp_cprc_base_type |
| 3334 | { |
| 3335 | VFP_CPRC_UNKNOWN, |
| 3336 | VFP_CPRC_SINGLE, |
| 3337 | VFP_CPRC_DOUBLE, |
| 3338 | VFP_CPRC_VEC64, |
| 3339 | VFP_CPRC_VEC128 |
| 3340 | }; |
| 3341 | |
| 3342 | /* The length of one element of base type B. */ |
| 3343 | |
| 3344 | static unsigned |
| 3345 | arm_vfp_cprc_unit_length (enum arm_vfp_cprc_base_type b) |
| 3346 | { |
| 3347 | switch (b) |
| 3348 | { |
| 3349 | case VFP_CPRC_SINGLE: |
| 3350 | return 4; |
| 3351 | case VFP_CPRC_DOUBLE: |
| 3352 | return 8; |
| 3353 | case VFP_CPRC_VEC64: |
| 3354 | return 8; |
| 3355 | case VFP_CPRC_VEC128: |
| 3356 | return 16; |
| 3357 | default: |
| 3358 | internal_error (__FILE__, __LINE__, _("Invalid VFP CPRC type: %d."), |
| 3359 | (int) b); |
| 3360 | } |
| 3361 | } |
| 3362 | |
| 3363 | /* The character ('s', 'd' or 'q') for the type of VFP register used |
| 3364 | for passing base type B. */ |
| 3365 | |
| 3366 | static int |
| 3367 | arm_vfp_cprc_reg_char (enum arm_vfp_cprc_base_type b) |
| 3368 | { |
| 3369 | switch (b) |
| 3370 | { |
| 3371 | case VFP_CPRC_SINGLE: |
| 3372 | return 's'; |
| 3373 | case VFP_CPRC_DOUBLE: |
| 3374 | return 'd'; |
| 3375 | case VFP_CPRC_VEC64: |
| 3376 | return 'd'; |
| 3377 | case VFP_CPRC_VEC128: |
| 3378 | return 'q'; |
| 3379 | default: |
| 3380 | internal_error (__FILE__, __LINE__, _("Invalid VFP CPRC type: %d."), |
| 3381 | (int) b); |
| 3382 | } |
| 3383 | } |
| 3384 | |
| 3385 | /* Determine whether T may be part of a candidate for passing and |
| 3386 | returning in VFP registers, ignoring the limit on the total number |
| 3387 | of components. If *BASE_TYPE is VFP_CPRC_UNKNOWN, set it to the |
| 3388 | classification of the first valid component found; if it is not |
| 3389 | VFP_CPRC_UNKNOWN, all components must have the same classification |
| 3390 | as *BASE_TYPE. If it is found that T contains a type not permitted |
| 3391 | for passing and returning in VFP registers, a type differently |
| 3392 | classified from *BASE_TYPE, or two types differently classified |
| 3393 | from each other, return -1, otherwise return the total number of |
| 3394 | base-type elements found (possibly 0 in an empty structure or |
| 3395 | array). Vectors and complex types are not currently supported, |
| 3396 | matching the generic AAPCS support. */ |
| 3397 | |
| 3398 | static int |
| 3399 | arm_vfp_cprc_sub_candidate (struct type *t, |
| 3400 | enum arm_vfp_cprc_base_type *base_type) |
| 3401 | { |
| 3402 | t = check_typedef (t); |
| 3403 | switch (TYPE_CODE (t)) |
| 3404 | { |
| 3405 | case TYPE_CODE_FLT: |
| 3406 | switch (TYPE_LENGTH (t)) |
| 3407 | { |
| 3408 | case 4: |
| 3409 | if (*base_type == VFP_CPRC_UNKNOWN) |
| 3410 | *base_type = VFP_CPRC_SINGLE; |
| 3411 | else if (*base_type != VFP_CPRC_SINGLE) |
| 3412 | return -1; |
| 3413 | return 1; |
| 3414 | |
| 3415 | case 8: |
| 3416 | if (*base_type == VFP_CPRC_UNKNOWN) |
| 3417 | *base_type = VFP_CPRC_DOUBLE; |
| 3418 | else if (*base_type != VFP_CPRC_DOUBLE) |
| 3419 | return -1; |
| 3420 | return 1; |
| 3421 | |
| 3422 | default: |
| 3423 | return -1; |
| 3424 | } |
| 3425 | break; |
| 3426 | |
| 3427 | case TYPE_CODE_ARRAY: |
| 3428 | { |
| 3429 | int count; |
| 3430 | unsigned unitlen; |
| 3431 | count = arm_vfp_cprc_sub_candidate (TYPE_TARGET_TYPE (t), base_type); |
| 3432 | if (count == -1) |
| 3433 | return -1; |
| 3434 | if (TYPE_LENGTH (t) == 0) |
| 3435 | { |
| 3436 | gdb_assert (count == 0); |
| 3437 | return 0; |
| 3438 | } |
| 3439 | else if (count == 0) |
| 3440 | return -1; |
| 3441 | unitlen = arm_vfp_cprc_unit_length (*base_type); |
| 3442 | gdb_assert ((TYPE_LENGTH (t) % unitlen) == 0); |
| 3443 | return TYPE_LENGTH (t) / unitlen; |
| 3444 | } |
| 3445 | break; |
| 3446 | |
| 3447 | case TYPE_CODE_STRUCT: |
| 3448 | { |
| 3449 | int count = 0; |
| 3450 | unsigned unitlen; |
| 3451 | int i; |
| 3452 | for (i = 0; i < TYPE_NFIELDS (t); i++) |
| 3453 | { |
| 3454 | int sub_count = arm_vfp_cprc_sub_candidate (TYPE_FIELD_TYPE (t, i), |
| 3455 | base_type); |
| 3456 | if (sub_count == -1) |
| 3457 | return -1; |
| 3458 | count += sub_count; |
| 3459 | } |
| 3460 | if (TYPE_LENGTH (t) == 0) |
| 3461 | { |
| 3462 | gdb_assert (count == 0); |
| 3463 | return 0; |
| 3464 | } |
| 3465 | else if (count == 0) |
| 3466 | return -1; |
| 3467 | unitlen = arm_vfp_cprc_unit_length (*base_type); |
| 3468 | if (TYPE_LENGTH (t) != unitlen * count) |
| 3469 | return -1; |
| 3470 | return count; |
| 3471 | } |
| 3472 | |
| 3473 | case TYPE_CODE_UNION: |
| 3474 | { |
| 3475 | int count = 0; |
| 3476 | unsigned unitlen; |
| 3477 | int i; |
| 3478 | for (i = 0; i < TYPE_NFIELDS (t); i++) |
| 3479 | { |
| 3480 | int sub_count = arm_vfp_cprc_sub_candidate (TYPE_FIELD_TYPE (t, i), |
| 3481 | base_type); |
| 3482 | if (sub_count == -1) |
| 3483 | return -1; |
| 3484 | count = (count > sub_count ? count : sub_count); |
| 3485 | } |
| 3486 | if (TYPE_LENGTH (t) == 0) |
| 3487 | { |
| 3488 | gdb_assert (count == 0); |
| 3489 | return 0; |
| 3490 | } |
| 3491 | else if (count == 0) |
| 3492 | return -1; |
| 3493 | unitlen = arm_vfp_cprc_unit_length (*base_type); |
| 3494 | if (TYPE_LENGTH (t) != unitlen * count) |
| 3495 | return -1; |
| 3496 | return count; |
| 3497 | } |
| 3498 | |
| 3499 | default: |
| 3500 | break; |
| 3501 | } |
| 3502 | |
| 3503 | return -1; |
| 3504 | } |
| 3505 | |
| 3506 | /* Determine whether T is a VFP co-processor register candidate (CPRC) |
| 3507 | if passed to or returned from a non-variadic function with the VFP |
| 3508 | ABI in effect. Return 1 if it is, 0 otherwise. If it is, set |
| 3509 | *BASE_TYPE to the base type for T and *COUNT to the number of |
| 3510 | elements of that base type before returning. */ |
| 3511 | |
| 3512 | static int |
| 3513 | arm_vfp_call_candidate (struct type *t, enum arm_vfp_cprc_base_type *base_type, |
| 3514 | int *count) |
| 3515 | { |
| 3516 | enum arm_vfp_cprc_base_type b = VFP_CPRC_UNKNOWN; |
| 3517 | int c = arm_vfp_cprc_sub_candidate (t, &b); |
| 3518 | if (c <= 0 || c > 4) |
| 3519 | return 0; |
| 3520 | *base_type = b; |
| 3521 | *count = c; |
| 3522 | return 1; |
| 3523 | } |
| 3524 | |
| 3525 | /* Return 1 if the VFP ABI should be used for passing arguments to and |
| 3526 | returning values from a function of type FUNC_TYPE, 0 |
| 3527 | otherwise. */ |
| 3528 | |
| 3529 | static int |
| 3530 | arm_vfp_abi_for_function (struct gdbarch *gdbarch, struct type *func_type) |
| 3531 | { |
| 3532 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 3533 | /* Variadic functions always use the base ABI. Assume that functions |
| 3534 | without debug info are not variadic. */ |
| 3535 | if (func_type && TYPE_VARARGS (check_typedef (func_type))) |
| 3536 | return 0; |
| 3537 | /* The VFP ABI is only supported as a variant of AAPCS. */ |
| 3538 | if (tdep->arm_abi != ARM_ABI_AAPCS) |
| 3539 | return 0; |
| 3540 | return gdbarch_tdep (gdbarch)->fp_model == ARM_FLOAT_VFP; |
| 3541 | } |
| 3542 | |
| 3543 | /* We currently only support passing parameters in integer registers, which |
| 3544 | conforms with GCC's default model, and VFP argument passing following |
| 3545 | the VFP variant of AAPCS. Several other variants exist and |
| 3546 | we should probably support some of them based on the selected ABI. */ |
| 3547 | |
| 3548 | static CORE_ADDR |
| 3549 | arm_push_dummy_call (struct gdbarch *gdbarch, struct value *function, |
| 3550 | struct regcache *regcache, CORE_ADDR bp_addr, int nargs, |
| 3551 | struct value **args, CORE_ADDR sp, int struct_return, |
| 3552 | CORE_ADDR struct_addr) |
| 3553 | { |
| 3554 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 3555 | int argnum; |
| 3556 | int argreg; |
| 3557 | int nstack; |
| 3558 | struct stack_item *si = NULL; |
| 3559 | int use_vfp_abi; |
| 3560 | struct type *ftype; |
| 3561 | unsigned vfp_regs_free = (1 << 16) - 1; |
| 3562 | |
| 3563 | /* Determine the type of this function and whether the VFP ABI |
| 3564 | applies. */ |
| 3565 | ftype = check_typedef (value_type (function)); |
| 3566 | if (TYPE_CODE (ftype) == TYPE_CODE_PTR) |
| 3567 | ftype = check_typedef (TYPE_TARGET_TYPE (ftype)); |
| 3568 | use_vfp_abi = arm_vfp_abi_for_function (gdbarch, ftype); |
| 3569 | |
| 3570 | /* Set the return address. For the ARM, the return breakpoint is |
| 3571 | always at BP_ADDR. */ |
| 3572 | if (arm_pc_is_thumb (gdbarch, bp_addr)) |
| 3573 | bp_addr |= 1; |
| 3574 | regcache_cooked_write_unsigned (regcache, ARM_LR_REGNUM, bp_addr); |
| 3575 | |
| 3576 | /* Walk through the list of args and determine how large a temporary |
| 3577 | stack is required. Need to take care here as structs may be |
| 3578 | passed on the stack, and we have to to push them. */ |
| 3579 | nstack = 0; |
| 3580 | |
| 3581 | argreg = ARM_A1_REGNUM; |
| 3582 | nstack = 0; |
| 3583 | |
| 3584 | /* The struct_return pointer occupies the first parameter |
| 3585 | passing register. */ |
| 3586 | if (struct_return) |
| 3587 | { |
| 3588 | if (arm_debug) |
| 3589 | fprintf_unfiltered (gdb_stdlog, "struct return in %s = %s\n", |
| 3590 | gdbarch_register_name (gdbarch, argreg), |
| 3591 | paddress (gdbarch, struct_addr)); |
| 3592 | regcache_cooked_write_unsigned (regcache, argreg, struct_addr); |
| 3593 | argreg++; |
| 3594 | } |
| 3595 | |
| 3596 | for (argnum = 0; argnum < nargs; argnum++) |
| 3597 | { |
| 3598 | int len; |
| 3599 | struct type *arg_type; |
| 3600 | struct type *target_type; |
| 3601 | enum type_code typecode; |
| 3602 | const bfd_byte *val; |
| 3603 | int align; |
| 3604 | enum arm_vfp_cprc_base_type vfp_base_type; |
| 3605 | int vfp_base_count; |
| 3606 | int may_use_core_reg = 1; |
| 3607 | |
| 3608 | arg_type = check_typedef (value_type (args[argnum])); |
| 3609 | len = TYPE_LENGTH (arg_type); |
| 3610 | target_type = TYPE_TARGET_TYPE (arg_type); |
| 3611 | typecode = TYPE_CODE (arg_type); |
| 3612 | val = value_contents (args[argnum]); |
| 3613 | |
| 3614 | align = arm_type_align (arg_type); |
| 3615 | /* Round alignment up to a whole number of words. */ |
| 3616 | align = (align + INT_REGISTER_SIZE - 1) & ~(INT_REGISTER_SIZE - 1); |
| 3617 | /* Different ABIs have different maximum alignments. */ |
| 3618 | if (gdbarch_tdep (gdbarch)->arm_abi == ARM_ABI_APCS) |
| 3619 | { |
| 3620 | /* The APCS ABI only requires word alignment. */ |
| 3621 | align = INT_REGISTER_SIZE; |
| 3622 | } |
| 3623 | else |
| 3624 | { |
| 3625 | /* The AAPCS requires at most doubleword alignment. */ |
| 3626 | if (align > INT_REGISTER_SIZE * 2) |
| 3627 | align = INT_REGISTER_SIZE * 2; |
| 3628 | } |
| 3629 | |
| 3630 | if (use_vfp_abi |
| 3631 | && arm_vfp_call_candidate (arg_type, &vfp_base_type, |
| 3632 | &vfp_base_count)) |
| 3633 | { |
| 3634 | int regno; |
| 3635 | int unit_length; |
| 3636 | int shift; |
| 3637 | unsigned mask; |
| 3638 | |
| 3639 | /* Because this is a CPRC it cannot go in a core register or |
| 3640 | cause a core register to be skipped for alignment. |
| 3641 | Either it goes in VFP registers and the rest of this loop |
| 3642 | iteration is skipped for this argument, or it goes on the |
| 3643 | stack (and the stack alignment code is correct for this |
| 3644 | case). */ |
| 3645 | may_use_core_reg = 0; |
| 3646 | |
| 3647 | unit_length = arm_vfp_cprc_unit_length (vfp_base_type); |
| 3648 | shift = unit_length / 4; |
| 3649 | mask = (1 << (shift * vfp_base_count)) - 1; |
| 3650 | for (regno = 0; regno < 16; regno += shift) |
| 3651 | if (((vfp_regs_free >> regno) & mask) == mask) |
| 3652 | break; |
| 3653 | |
| 3654 | if (regno < 16) |
| 3655 | { |
| 3656 | int reg_char; |
| 3657 | int reg_scaled; |
| 3658 | int i; |
| 3659 | |
| 3660 | vfp_regs_free &= ~(mask << regno); |
| 3661 | reg_scaled = regno / shift; |
| 3662 | reg_char = arm_vfp_cprc_reg_char (vfp_base_type); |
| 3663 | for (i = 0; i < vfp_base_count; i++) |
| 3664 | { |
| 3665 | char name_buf[4]; |
| 3666 | int regnum; |
| 3667 | if (reg_char == 'q') |
| 3668 | arm_neon_quad_write (gdbarch, regcache, reg_scaled + i, |
| 3669 | val + i * unit_length); |
| 3670 | else |
| 3671 | { |
| 3672 | sprintf (name_buf, "%c%d", reg_char, reg_scaled + i); |
| 3673 | regnum = user_reg_map_name_to_regnum (gdbarch, name_buf, |
| 3674 | strlen (name_buf)); |
| 3675 | regcache_cooked_write (regcache, regnum, |
| 3676 | val + i * unit_length); |
| 3677 | } |
| 3678 | } |
| 3679 | continue; |
| 3680 | } |
| 3681 | else |
| 3682 | { |
| 3683 | /* This CPRC could not go in VFP registers, so all VFP |
| 3684 | registers are now marked as used. */ |
| 3685 | vfp_regs_free = 0; |
| 3686 | } |
| 3687 | } |
| 3688 | |
| 3689 | /* Push stack padding for dowubleword alignment. */ |
| 3690 | if (nstack & (align - 1)) |
| 3691 | { |
| 3692 | si = push_stack_item (si, val, INT_REGISTER_SIZE); |
| 3693 | nstack += INT_REGISTER_SIZE; |
| 3694 | } |
| 3695 | |
| 3696 | /* Doubleword aligned quantities must go in even register pairs. */ |
| 3697 | if (may_use_core_reg |
| 3698 | && argreg <= ARM_LAST_ARG_REGNUM |
| 3699 | && align > INT_REGISTER_SIZE |
| 3700 | && argreg & 1) |
| 3701 | argreg++; |
| 3702 | |
| 3703 | /* If the argument is a pointer to a function, and it is a |
| 3704 | Thumb function, create a LOCAL copy of the value and set |
| 3705 | the THUMB bit in it. */ |
| 3706 | if (TYPE_CODE_PTR == typecode |
| 3707 | && target_type != NULL |
| 3708 | && TYPE_CODE_FUNC == TYPE_CODE (check_typedef (target_type))) |
| 3709 | { |
| 3710 | CORE_ADDR regval = extract_unsigned_integer (val, len, byte_order); |
| 3711 | if (arm_pc_is_thumb (gdbarch, regval)) |
| 3712 | { |
| 3713 | bfd_byte *copy = alloca (len); |
| 3714 | store_unsigned_integer (copy, len, byte_order, |
| 3715 | MAKE_THUMB_ADDR (regval)); |
| 3716 | val = copy; |
| 3717 | } |
| 3718 | } |
| 3719 | |
| 3720 | /* Copy the argument to general registers or the stack in |
| 3721 | register-sized pieces. Large arguments are split between |
| 3722 | registers and stack. */ |
| 3723 | while (len > 0) |
| 3724 | { |
| 3725 | int partial_len = len < INT_REGISTER_SIZE ? len : INT_REGISTER_SIZE; |
| 3726 | |
| 3727 | if (may_use_core_reg && argreg <= ARM_LAST_ARG_REGNUM) |
| 3728 | { |
| 3729 | /* The argument is being passed in a general purpose |
| 3730 | register. */ |
| 3731 | CORE_ADDR regval |
| 3732 | = extract_unsigned_integer (val, partial_len, byte_order); |
| 3733 | if (byte_order == BFD_ENDIAN_BIG) |
| 3734 | regval <<= (INT_REGISTER_SIZE - partial_len) * 8; |
| 3735 | if (arm_debug) |
| 3736 | fprintf_unfiltered (gdb_stdlog, "arg %d in %s = 0x%s\n", |
| 3737 | argnum, |
| 3738 | gdbarch_register_name |
| 3739 | (gdbarch, argreg), |
| 3740 | phex (regval, INT_REGISTER_SIZE)); |
| 3741 | regcache_cooked_write_unsigned (regcache, argreg, regval); |
| 3742 | argreg++; |
| 3743 | } |
| 3744 | else |
| 3745 | { |
| 3746 | /* Push the arguments onto the stack. */ |
| 3747 | if (arm_debug) |
| 3748 | fprintf_unfiltered (gdb_stdlog, "arg %d @ sp + %d\n", |
| 3749 | argnum, nstack); |
| 3750 | si = push_stack_item (si, val, INT_REGISTER_SIZE); |
| 3751 | nstack += INT_REGISTER_SIZE; |
| 3752 | } |
| 3753 | |
| 3754 | len -= partial_len; |
| 3755 | val += partial_len; |
| 3756 | } |
| 3757 | } |
| 3758 | /* If we have an odd number of words to push, then decrement the stack |
| 3759 | by one word now, so first stack argument will be dword aligned. */ |
| 3760 | if (nstack & 4) |
| 3761 | sp -= 4; |
| 3762 | |
| 3763 | while (si) |
| 3764 | { |
| 3765 | sp -= si->len; |
| 3766 | write_memory (sp, si->data, si->len); |
| 3767 | si = pop_stack_item (si); |
| 3768 | } |
| 3769 | |
| 3770 | /* Finally, update teh SP register. */ |
| 3771 | regcache_cooked_write_unsigned (regcache, ARM_SP_REGNUM, sp); |
| 3772 | |
| 3773 | return sp; |
| 3774 | } |
| 3775 | |
| 3776 | |
| 3777 | /* Always align the frame to an 8-byte boundary. This is required on |
| 3778 | some platforms and harmless on the rest. */ |
| 3779 | |
| 3780 | static CORE_ADDR |
| 3781 | arm_frame_align (struct gdbarch *gdbarch, CORE_ADDR sp) |
| 3782 | { |
| 3783 | /* Align the stack to eight bytes. */ |
| 3784 | return sp & ~ (CORE_ADDR) 7; |
| 3785 | } |
| 3786 | |
| 3787 | static void |
| 3788 | print_fpu_flags (int flags) |
| 3789 | { |
| 3790 | if (flags & (1 << 0)) |
| 3791 | fputs ("IVO ", stdout); |
| 3792 | if (flags & (1 << 1)) |
| 3793 | fputs ("DVZ ", stdout); |
| 3794 | if (flags & (1 << 2)) |
| 3795 | fputs ("OFL ", stdout); |
| 3796 | if (flags & (1 << 3)) |
| 3797 | fputs ("UFL ", stdout); |
| 3798 | if (flags & (1 << 4)) |
| 3799 | fputs ("INX ", stdout); |
| 3800 | putchar ('\n'); |
| 3801 | } |
| 3802 | |
| 3803 | /* Print interesting information about the floating point processor |
| 3804 | (if present) or emulator. */ |
| 3805 | static void |
| 3806 | arm_print_float_info (struct gdbarch *gdbarch, struct ui_file *file, |
| 3807 | struct frame_info *frame, const char *args) |
| 3808 | { |
| 3809 | unsigned long status = get_frame_register_unsigned (frame, ARM_FPS_REGNUM); |
| 3810 | int type; |
| 3811 | |
| 3812 | type = (status >> 24) & 127; |
| 3813 | if (status & (1 << 31)) |
| 3814 | printf (_("Hardware FPU type %d\n"), type); |
| 3815 | else |
| 3816 | printf (_("Software FPU type %d\n"), type); |
| 3817 | /* i18n: [floating point unit] mask */ |
| 3818 | fputs (_("mask: "), stdout); |
| 3819 | print_fpu_flags (status >> 16); |
| 3820 | /* i18n: [floating point unit] flags */ |
| 3821 | fputs (_("flags: "), stdout); |
| 3822 | print_fpu_flags (status); |
| 3823 | } |
| 3824 | |
| 3825 | /* Construct the ARM extended floating point type. */ |
| 3826 | static struct type * |
| 3827 | arm_ext_type (struct gdbarch *gdbarch) |
| 3828 | { |
| 3829 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 3830 | |
| 3831 | if (!tdep->arm_ext_type) |
| 3832 | tdep->arm_ext_type |
| 3833 | = arch_float_type (gdbarch, -1, "builtin_type_arm_ext", |
| 3834 | floatformats_arm_ext); |
| 3835 | |
| 3836 | return tdep->arm_ext_type; |
| 3837 | } |
| 3838 | |
| 3839 | static struct type * |
| 3840 | arm_neon_double_type (struct gdbarch *gdbarch) |
| 3841 | { |
| 3842 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 3843 | |
| 3844 | if (tdep->neon_double_type == NULL) |
| 3845 | { |
| 3846 | struct type *t, *elem; |
| 3847 | |
| 3848 | t = arch_composite_type (gdbarch, "__gdb_builtin_type_neon_d", |
| 3849 | TYPE_CODE_UNION); |
| 3850 | elem = builtin_type (gdbarch)->builtin_uint8; |
| 3851 | append_composite_type_field (t, "u8", init_vector_type (elem, 8)); |
| 3852 | elem = builtin_type (gdbarch)->builtin_uint16; |
| 3853 | append_composite_type_field (t, "u16", init_vector_type (elem, 4)); |
| 3854 | elem = builtin_type (gdbarch)->builtin_uint32; |
| 3855 | append_composite_type_field (t, "u32", init_vector_type (elem, 2)); |
| 3856 | elem = builtin_type (gdbarch)->builtin_uint64; |
| 3857 | append_composite_type_field (t, "u64", elem); |
| 3858 | elem = builtin_type (gdbarch)->builtin_float; |
| 3859 | append_composite_type_field (t, "f32", init_vector_type (elem, 2)); |
| 3860 | elem = builtin_type (gdbarch)->builtin_double; |
| 3861 | append_composite_type_field (t, "f64", elem); |
| 3862 | |
| 3863 | TYPE_VECTOR (t) = 1; |
| 3864 | TYPE_NAME (t) = "neon_d"; |
| 3865 | tdep->neon_double_type = t; |
| 3866 | } |
| 3867 | |
| 3868 | return tdep->neon_double_type; |
| 3869 | } |
| 3870 | |
| 3871 | /* FIXME: The vector types are not correctly ordered on big-endian |
| 3872 | targets. Just as s0 is the low bits of d0, d0[0] is also the low |
| 3873 | bits of d0 - regardless of what unit size is being held in d0. So |
| 3874 | the offset of the first uint8 in d0 is 7, but the offset of the |
| 3875 | first float is 4. This code works as-is for little-endian |
| 3876 | targets. */ |
| 3877 | |
| 3878 | static struct type * |
| 3879 | arm_neon_quad_type (struct gdbarch *gdbarch) |
| 3880 | { |
| 3881 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 3882 | |
| 3883 | if (tdep->neon_quad_type == NULL) |
| 3884 | { |
| 3885 | struct type *t, *elem; |
| 3886 | |
| 3887 | t = arch_composite_type (gdbarch, "__gdb_builtin_type_neon_q", |
| 3888 | TYPE_CODE_UNION); |
| 3889 | elem = builtin_type (gdbarch)->builtin_uint8; |
| 3890 | append_composite_type_field (t, "u8", init_vector_type (elem, 16)); |
| 3891 | elem = builtin_type (gdbarch)->builtin_uint16; |
| 3892 | append_composite_type_field (t, "u16", init_vector_type (elem, 8)); |
| 3893 | elem = builtin_type (gdbarch)->builtin_uint32; |
| 3894 | append_composite_type_field (t, "u32", init_vector_type (elem, 4)); |
| 3895 | elem = builtin_type (gdbarch)->builtin_uint64; |
| 3896 | append_composite_type_field (t, "u64", init_vector_type (elem, 2)); |
| 3897 | elem = builtin_type (gdbarch)->builtin_float; |
| 3898 | append_composite_type_field (t, "f32", init_vector_type (elem, 4)); |
| 3899 | elem = builtin_type (gdbarch)->builtin_double; |
| 3900 | append_composite_type_field (t, "f64", init_vector_type (elem, 2)); |
| 3901 | |
| 3902 | TYPE_VECTOR (t) = 1; |
| 3903 | TYPE_NAME (t) = "neon_q"; |
| 3904 | tdep->neon_quad_type = t; |
| 3905 | } |
| 3906 | |
| 3907 | return tdep->neon_quad_type; |
| 3908 | } |
| 3909 | |
| 3910 | /* Return the GDB type object for the "standard" data type of data in |
| 3911 | register N. */ |
| 3912 | |
| 3913 | static struct type * |
| 3914 | arm_register_type (struct gdbarch *gdbarch, int regnum) |
| 3915 | { |
| 3916 | int num_regs = gdbarch_num_regs (gdbarch); |
| 3917 | |
| 3918 | if (gdbarch_tdep (gdbarch)->have_vfp_pseudos |
| 3919 | && regnum >= num_regs && regnum < num_regs + 32) |
| 3920 | return builtin_type (gdbarch)->builtin_float; |
| 3921 | |
| 3922 | if (gdbarch_tdep (gdbarch)->have_neon_pseudos |
| 3923 | && regnum >= num_regs + 32 && regnum < num_regs + 32 + 16) |
| 3924 | return arm_neon_quad_type (gdbarch); |
| 3925 | |
| 3926 | /* If the target description has register information, we are only |
| 3927 | in this function so that we can override the types of |
| 3928 | double-precision registers for NEON. */ |
| 3929 | if (tdesc_has_registers (gdbarch_target_desc (gdbarch))) |
| 3930 | { |
| 3931 | struct type *t = tdesc_register_type (gdbarch, regnum); |
| 3932 | |
| 3933 | if (regnum >= ARM_D0_REGNUM && regnum < ARM_D0_REGNUM + 32 |
| 3934 | && TYPE_CODE (t) == TYPE_CODE_FLT |
| 3935 | && gdbarch_tdep (gdbarch)->have_neon) |
| 3936 | return arm_neon_double_type (gdbarch); |
| 3937 | else |
| 3938 | return t; |
| 3939 | } |
| 3940 | |
| 3941 | if (regnum >= ARM_F0_REGNUM && regnum < ARM_F0_REGNUM + NUM_FREGS) |
| 3942 | { |
| 3943 | if (!gdbarch_tdep (gdbarch)->have_fpa_registers) |
| 3944 | return builtin_type (gdbarch)->builtin_void; |
| 3945 | |
| 3946 | return arm_ext_type (gdbarch); |
| 3947 | } |
| 3948 | else if (regnum == ARM_SP_REGNUM) |
| 3949 | return builtin_type (gdbarch)->builtin_data_ptr; |
| 3950 | else if (regnum == ARM_PC_REGNUM) |
| 3951 | return builtin_type (gdbarch)->builtin_func_ptr; |
| 3952 | else if (regnum >= ARRAY_SIZE (arm_register_names)) |
| 3953 | /* These registers are only supported on targets which supply |
| 3954 | an XML description. */ |
| 3955 | return builtin_type (gdbarch)->builtin_int0; |
| 3956 | else |
| 3957 | return builtin_type (gdbarch)->builtin_uint32; |
| 3958 | } |
| 3959 | |
| 3960 | /* Map a DWARF register REGNUM onto the appropriate GDB register |
| 3961 | number. */ |
| 3962 | |
| 3963 | static int |
| 3964 | arm_dwarf_reg_to_regnum (struct gdbarch *gdbarch, int reg) |
| 3965 | { |
| 3966 | /* Core integer regs. */ |
| 3967 | if (reg >= 0 && reg <= 15) |
| 3968 | return reg; |
| 3969 | |
| 3970 | /* Legacy FPA encoding. These were once used in a way which |
| 3971 | overlapped with VFP register numbering, so their use is |
| 3972 | discouraged, but GDB doesn't support the ARM toolchain |
| 3973 | which used them for VFP. */ |
| 3974 | if (reg >= 16 && reg <= 23) |
| 3975 | return ARM_F0_REGNUM + reg - 16; |
| 3976 | |
| 3977 | /* New assignments for the FPA registers. */ |
| 3978 | if (reg >= 96 && reg <= 103) |
| 3979 | return ARM_F0_REGNUM + reg - 96; |
| 3980 | |
| 3981 | /* WMMX register assignments. */ |
| 3982 | if (reg >= 104 && reg <= 111) |
| 3983 | return ARM_WCGR0_REGNUM + reg - 104; |
| 3984 | |
| 3985 | if (reg >= 112 && reg <= 127) |
| 3986 | return ARM_WR0_REGNUM + reg - 112; |
| 3987 | |
| 3988 | if (reg >= 192 && reg <= 199) |
| 3989 | return ARM_WC0_REGNUM + reg - 192; |
| 3990 | |
| 3991 | /* VFP v2 registers. A double precision value is actually |
| 3992 | in d1 rather than s2, but the ABI only defines numbering |
| 3993 | for the single precision registers. This will "just work" |
| 3994 | in GDB for little endian targets (we'll read eight bytes, |
| 3995 | starting in s0 and then progressing to s1), but will be |
| 3996 | reversed on big endian targets with VFP. This won't |
| 3997 | be a problem for the new Neon quad registers; you're supposed |
| 3998 | to use DW_OP_piece for those. */ |
| 3999 | if (reg >= 64 && reg <= 95) |
| 4000 | { |
| 4001 | char name_buf[4]; |
| 4002 | |
| 4003 | sprintf (name_buf, "s%d", reg - 64); |
| 4004 | return user_reg_map_name_to_regnum (gdbarch, name_buf, |
| 4005 | strlen (name_buf)); |
| 4006 | } |
| 4007 | |
| 4008 | /* VFP v3 / Neon registers. This range is also used for VFP v2 |
| 4009 | registers, except that it now describes d0 instead of s0. */ |
| 4010 | if (reg >= 256 && reg <= 287) |
| 4011 | { |
| 4012 | char name_buf[4]; |
| 4013 | |
| 4014 | sprintf (name_buf, "d%d", reg - 256); |
| 4015 | return user_reg_map_name_to_regnum (gdbarch, name_buf, |
| 4016 | strlen (name_buf)); |
| 4017 | } |
| 4018 | |
| 4019 | return -1; |
| 4020 | } |
| 4021 | |
| 4022 | /* Map GDB internal REGNUM onto the Arm simulator register numbers. */ |
| 4023 | static int |
| 4024 | arm_register_sim_regno (struct gdbarch *gdbarch, int regnum) |
| 4025 | { |
| 4026 | int reg = regnum; |
| 4027 | gdb_assert (reg >= 0 && reg < gdbarch_num_regs (gdbarch)); |
| 4028 | |
| 4029 | if (regnum >= ARM_WR0_REGNUM && regnum <= ARM_WR15_REGNUM) |
| 4030 | return regnum - ARM_WR0_REGNUM + SIM_ARM_IWMMXT_COP0R0_REGNUM; |
| 4031 | |
| 4032 | if (regnum >= ARM_WC0_REGNUM && regnum <= ARM_WC7_REGNUM) |
| 4033 | return regnum - ARM_WC0_REGNUM + SIM_ARM_IWMMXT_COP1R0_REGNUM; |
| 4034 | |
| 4035 | if (regnum >= ARM_WCGR0_REGNUM && regnum <= ARM_WCGR7_REGNUM) |
| 4036 | return regnum - ARM_WCGR0_REGNUM + SIM_ARM_IWMMXT_COP1R8_REGNUM; |
| 4037 | |
| 4038 | if (reg < NUM_GREGS) |
| 4039 | return SIM_ARM_R0_REGNUM + reg; |
| 4040 | reg -= NUM_GREGS; |
| 4041 | |
| 4042 | if (reg < NUM_FREGS) |
| 4043 | return SIM_ARM_FP0_REGNUM + reg; |
| 4044 | reg -= NUM_FREGS; |
| 4045 | |
| 4046 | if (reg < NUM_SREGS) |
| 4047 | return SIM_ARM_FPS_REGNUM + reg; |
| 4048 | reg -= NUM_SREGS; |
| 4049 | |
| 4050 | internal_error (__FILE__, __LINE__, _("Bad REGNUM %d"), regnum); |
| 4051 | } |
| 4052 | |
| 4053 | /* NOTE: cagney/2001-08-20: Both convert_from_extended() and |
| 4054 | convert_to_extended() use floatformat_arm_ext_littlebyte_bigword. |
| 4055 | It is thought that this is is the floating-point register format on |
| 4056 | little-endian systems. */ |
| 4057 | |
| 4058 | static void |
| 4059 | convert_from_extended (const struct floatformat *fmt, const void *ptr, |
| 4060 | void *dbl, int endianess) |
| 4061 | { |
| 4062 | DOUBLEST d; |
| 4063 | |
| 4064 | if (endianess == BFD_ENDIAN_BIG) |
| 4065 | floatformat_to_doublest (&floatformat_arm_ext_big, ptr, &d); |
| 4066 | else |
| 4067 | floatformat_to_doublest (&floatformat_arm_ext_littlebyte_bigword, |
| 4068 | ptr, &d); |
| 4069 | floatformat_from_doublest (fmt, &d, dbl); |
| 4070 | } |
| 4071 | |
| 4072 | static void |
| 4073 | convert_to_extended (const struct floatformat *fmt, void *dbl, const void *ptr, |
| 4074 | int endianess) |
| 4075 | { |
| 4076 | DOUBLEST d; |
| 4077 | |
| 4078 | floatformat_to_doublest (fmt, ptr, &d); |
| 4079 | if (endianess == BFD_ENDIAN_BIG) |
| 4080 | floatformat_from_doublest (&floatformat_arm_ext_big, &d, dbl); |
| 4081 | else |
| 4082 | floatformat_from_doublest (&floatformat_arm_ext_littlebyte_bigword, |
| 4083 | &d, dbl); |
| 4084 | } |
| 4085 | |
| 4086 | static int |
| 4087 | condition_true (unsigned long cond, unsigned long status_reg) |
| 4088 | { |
| 4089 | if (cond == INST_AL || cond == INST_NV) |
| 4090 | return 1; |
| 4091 | |
| 4092 | switch (cond) |
| 4093 | { |
| 4094 | case INST_EQ: |
| 4095 | return ((status_reg & FLAG_Z) != 0); |
| 4096 | case INST_NE: |
| 4097 | return ((status_reg & FLAG_Z) == 0); |
| 4098 | case INST_CS: |
| 4099 | return ((status_reg & FLAG_C) != 0); |
| 4100 | case INST_CC: |
| 4101 | return ((status_reg & FLAG_C) == 0); |
| 4102 | case INST_MI: |
| 4103 | return ((status_reg & FLAG_N) != 0); |
| 4104 | case INST_PL: |
| 4105 | return ((status_reg & FLAG_N) == 0); |
| 4106 | case INST_VS: |
| 4107 | return ((status_reg & FLAG_V) != 0); |
| 4108 | case INST_VC: |
| 4109 | return ((status_reg & FLAG_V) == 0); |
| 4110 | case INST_HI: |
| 4111 | return ((status_reg & (FLAG_C | FLAG_Z)) == FLAG_C); |
| 4112 | case INST_LS: |
| 4113 | return ((status_reg & (FLAG_C | FLAG_Z)) != FLAG_C); |
| 4114 | case INST_GE: |
| 4115 | return (((status_reg & FLAG_N) == 0) == ((status_reg & FLAG_V) == 0)); |
| 4116 | case INST_LT: |
| 4117 | return (((status_reg & FLAG_N) == 0) != ((status_reg & FLAG_V) == 0)); |
| 4118 | case INST_GT: |
| 4119 | return (((status_reg & FLAG_Z) == 0) |
| 4120 | && (((status_reg & FLAG_N) == 0) |
| 4121 | == ((status_reg & FLAG_V) == 0))); |
| 4122 | case INST_LE: |
| 4123 | return (((status_reg & FLAG_Z) != 0) |
| 4124 | || (((status_reg & FLAG_N) == 0) |
| 4125 | != ((status_reg & FLAG_V) == 0))); |
| 4126 | } |
| 4127 | return 1; |
| 4128 | } |
| 4129 | |
| 4130 | static unsigned long |
| 4131 | shifted_reg_val (struct frame_info *frame, unsigned long inst, int carry, |
| 4132 | unsigned long pc_val, unsigned long status_reg) |
| 4133 | { |
| 4134 | unsigned long res, shift; |
| 4135 | int rm = bits (inst, 0, 3); |
| 4136 | unsigned long shifttype = bits (inst, 5, 6); |
| 4137 | |
| 4138 | if (bit (inst, 4)) |
| 4139 | { |
| 4140 | int rs = bits (inst, 8, 11); |
| 4141 | shift = (rs == 15 ? pc_val + 8 |
| 4142 | : get_frame_register_unsigned (frame, rs)) & 0xFF; |
| 4143 | } |
| 4144 | else |
| 4145 | shift = bits (inst, 7, 11); |
| 4146 | |
| 4147 | res = (rm == ARM_PC_REGNUM |
| 4148 | ? (pc_val + (bit (inst, 4) ? 12 : 8)) |
| 4149 | : get_frame_register_unsigned (frame, rm)); |
| 4150 | |
| 4151 | switch (shifttype) |
| 4152 | { |
| 4153 | case 0: /* LSL */ |
| 4154 | res = shift >= 32 ? 0 : res << shift; |
| 4155 | break; |
| 4156 | |
| 4157 | case 1: /* LSR */ |
| 4158 | res = shift >= 32 ? 0 : res >> shift; |
| 4159 | break; |
| 4160 | |
| 4161 | case 2: /* ASR */ |
| 4162 | if (shift >= 32) |
| 4163 | shift = 31; |
| 4164 | res = ((res & 0x80000000L) |
| 4165 | ? ~((~res) >> shift) : res >> shift); |
| 4166 | break; |
| 4167 | |
| 4168 | case 3: /* ROR/RRX */ |
| 4169 | shift &= 31; |
| 4170 | if (shift == 0) |
| 4171 | res = (res >> 1) | (carry ? 0x80000000L : 0); |
| 4172 | else |
| 4173 | res = (res >> shift) | (res << (32 - shift)); |
| 4174 | break; |
| 4175 | } |
| 4176 | |
| 4177 | return res & 0xffffffff; |
| 4178 | } |
| 4179 | |
| 4180 | /* Return number of 1-bits in VAL. */ |
| 4181 | |
| 4182 | static int |
| 4183 | bitcount (unsigned long val) |
| 4184 | { |
| 4185 | int nbits; |
| 4186 | for (nbits = 0; val != 0; nbits++) |
| 4187 | val &= val - 1; /* Delete rightmost 1-bit in val. */ |
| 4188 | return nbits; |
| 4189 | } |
| 4190 | |
| 4191 | /* Return the size in bytes of the complete Thumb instruction whose |
| 4192 | first halfword is INST1. */ |
| 4193 | |
| 4194 | static int |
| 4195 | thumb_insn_size (unsigned short inst1) |
| 4196 | { |
| 4197 | if ((inst1 & 0xe000) == 0xe000 && (inst1 & 0x1800) != 0) |
| 4198 | return 4; |
| 4199 | else |
| 4200 | return 2; |
| 4201 | } |
| 4202 | |
| 4203 | static int |
| 4204 | thumb_advance_itstate (unsigned int itstate) |
| 4205 | { |
| 4206 | /* Preserve IT[7:5], the first three bits of the condition. Shift |
| 4207 | the upcoming condition flags left by one bit. */ |
| 4208 | itstate = (itstate & 0xe0) | ((itstate << 1) & 0x1f); |
| 4209 | |
| 4210 | /* If we have finished the IT block, clear the state. */ |
| 4211 | if ((itstate & 0x0f) == 0) |
| 4212 | itstate = 0; |
| 4213 | |
| 4214 | return itstate; |
| 4215 | } |
| 4216 | |
| 4217 | /* Find the next PC after the current instruction executes. In some |
| 4218 | cases we can not statically determine the answer (see the IT state |
| 4219 | handling in this function); in that case, a breakpoint may be |
| 4220 | inserted in addition to the returned PC, which will be used to set |
| 4221 | another breakpoint by our caller. */ |
| 4222 | |
| 4223 | static CORE_ADDR |
| 4224 | thumb_get_next_pc_raw (struct frame_info *frame, CORE_ADDR pc, int insert_bkpt) |
| 4225 | { |
| 4226 | struct gdbarch *gdbarch = get_frame_arch (frame); |
| 4227 | struct address_space *aspace = get_frame_address_space (frame); |
| 4228 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 4229 | enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch); |
| 4230 | unsigned long pc_val = ((unsigned long) pc) + 4; /* PC after prefetch */ |
| 4231 | unsigned short inst1; |
| 4232 | CORE_ADDR nextpc = pc + 2; /* Default is next instruction. */ |
| 4233 | unsigned long offset; |
| 4234 | ULONGEST status, itstate; |
| 4235 | |
| 4236 | nextpc = MAKE_THUMB_ADDR (nextpc); |
| 4237 | pc_val = MAKE_THUMB_ADDR (pc_val); |
| 4238 | |
| 4239 | inst1 = read_memory_unsigned_integer (pc, 2, byte_order_for_code); |
| 4240 | |
| 4241 | /* Thumb-2 conditional execution support. There are eight bits in |
| 4242 | the CPSR which describe conditional execution state. Once |
| 4243 | reconstructed (they're in a funny order), the low five bits |
| 4244 | describe the low bit of the condition for each instruction and |
| 4245 | how many instructions remain. The high three bits describe the |
| 4246 | base condition. One of the low four bits will be set if an IT |
| 4247 | block is active. These bits read as zero on earlier |
| 4248 | processors. */ |
| 4249 | status = get_frame_register_unsigned (frame, ARM_PS_REGNUM); |
| 4250 | itstate = ((status >> 8) & 0xfc) | ((status >> 25) & 0x3); |
| 4251 | |
| 4252 | /* If-Then handling. On GNU/Linux, where this routine is used, we |
| 4253 | use an undefined instruction as a breakpoint. Unlike BKPT, IT |
| 4254 | can disable execution of the undefined instruction. So we might |
| 4255 | miss the breakpoint if we set it on a skipped conditional |
| 4256 | instruction. Because conditional instructions can change the |
| 4257 | flags, affecting the execution of further instructions, we may |
| 4258 | need to set two breakpoints. */ |
| 4259 | |
| 4260 | if (gdbarch_tdep (gdbarch)->thumb2_breakpoint != NULL) |
| 4261 | { |
| 4262 | if ((inst1 & 0xff00) == 0xbf00 && (inst1 & 0x000f) != 0) |
| 4263 | { |
| 4264 | /* An IT instruction. Because this instruction does not |
| 4265 | modify the flags, we can accurately predict the next |
| 4266 | executed instruction. */ |
| 4267 | itstate = inst1 & 0x00ff; |
| 4268 | pc += thumb_insn_size (inst1); |
| 4269 | |
| 4270 | while (itstate != 0 && ! condition_true (itstate >> 4, status)) |
| 4271 | { |
| 4272 | inst1 = read_memory_unsigned_integer (pc, 2, |
| 4273 | byte_order_for_code); |
| 4274 | pc += thumb_insn_size (inst1); |
| 4275 | itstate = thumb_advance_itstate (itstate); |
| 4276 | } |
| 4277 | |
| 4278 | return MAKE_THUMB_ADDR (pc); |
| 4279 | } |
| 4280 | else if (itstate != 0) |
| 4281 | { |
| 4282 | /* We are in a conditional block. Check the condition. */ |
| 4283 | if (! condition_true (itstate >> 4, status)) |
| 4284 | { |
| 4285 | /* Advance to the next executed instruction. */ |
| 4286 | pc += thumb_insn_size (inst1); |
| 4287 | itstate = thumb_advance_itstate (itstate); |
| 4288 | |
| 4289 | while (itstate != 0 && ! condition_true (itstate >> 4, status)) |
| 4290 | { |
| 4291 | inst1 = read_memory_unsigned_integer (pc, 2, |
| 4292 | byte_order_for_code); |
| 4293 | pc += thumb_insn_size (inst1); |
| 4294 | itstate = thumb_advance_itstate (itstate); |
| 4295 | } |
| 4296 | |
| 4297 | return MAKE_THUMB_ADDR (pc); |
| 4298 | } |
| 4299 | else if ((itstate & 0x0f) == 0x08) |
| 4300 | { |
| 4301 | /* This is the last instruction of the conditional |
| 4302 | block, and it is executed. We can handle it normally |
| 4303 | because the following instruction is not conditional, |
| 4304 | and we must handle it normally because it is |
| 4305 | permitted to branch. Fall through. */ |
| 4306 | } |
| 4307 | else |
| 4308 | { |
| 4309 | int cond_negated; |
| 4310 | |
| 4311 | /* There are conditional instructions after this one. |
| 4312 | If this instruction modifies the flags, then we can |
| 4313 | not predict what the next executed instruction will |
| 4314 | be. Fortunately, this instruction is architecturally |
| 4315 | forbidden to branch; we know it will fall through. |
| 4316 | Start by skipping past it. */ |
| 4317 | pc += thumb_insn_size (inst1); |
| 4318 | itstate = thumb_advance_itstate (itstate); |
| 4319 | |
| 4320 | /* Set a breakpoint on the following instruction. */ |
| 4321 | gdb_assert ((itstate & 0x0f) != 0); |
| 4322 | if (insert_bkpt) |
| 4323 | insert_single_step_breakpoint (gdbarch, aspace, pc); |
| 4324 | cond_negated = (itstate >> 4) & 1; |
| 4325 | |
| 4326 | /* Skip all following instructions with the same |
| 4327 | condition. If there is a later instruction in the IT |
| 4328 | block with the opposite condition, set the other |
| 4329 | breakpoint there. If not, then set a breakpoint on |
| 4330 | the instruction after the IT block. */ |
| 4331 | do |
| 4332 | { |
| 4333 | inst1 = read_memory_unsigned_integer (pc, 2, |
| 4334 | byte_order_for_code); |
| 4335 | pc += thumb_insn_size (inst1); |
| 4336 | itstate = thumb_advance_itstate (itstate); |
| 4337 | } |
| 4338 | while (itstate != 0 && ((itstate >> 4) & 1) == cond_negated); |
| 4339 | |
| 4340 | return MAKE_THUMB_ADDR (pc); |
| 4341 | } |
| 4342 | } |
| 4343 | } |
| 4344 | else if (itstate & 0x0f) |
| 4345 | { |
| 4346 | /* We are in a conditional block. Check the condition. */ |
| 4347 | int cond = itstate >> 4; |
| 4348 | |
| 4349 | if (! condition_true (cond, status)) |
| 4350 | { |
| 4351 | /* Advance to the next instruction. All the 32-bit |
| 4352 | instructions share a common prefix. */ |
| 4353 | if ((inst1 & 0xe000) == 0xe000 && (inst1 & 0x1800) != 0) |
| 4354 | return MAKE_THUMB_ADDR (pc + 4); |
| 4355 | else |
| 4356 | return MAKE_THUMB_ADDR (pc + 2); |
| 4357 | } |
| 4358 | |
| 4359 | /* Otherwise, handle the instruction normally. */ |
| 4360 | } |
| 4361 | |
| 4362 | if ((inst1 & 0xff00) == 0xbd00) /* pop {rlist, pc} */ |
| 4363 | { |
| 4364 | CORE_ADDR sp; |
| 4365 | |
| 4366 | /* Fetch the saved PC from the stack. It's stored above |
| 4367 | all of the other registers. */ |
| 4368 | offset = bitcount (bits (inst1, 0, 7)) * INT_REGISTER_SIZE; |
| 4369 | sp = get_frame_register_unsigned (frame, ARM_SP_REGNUM); |
| 4370 | nextpc = read_memory_unsigned_integer (sp + offset, 4, byte_order); |
| 4371 | } |
| 4372 | else if ((inst1 & 0xf000) == 0xd000) /* conditional branch */ |
| 4373 | { |
| 4374 | unsigned long cond = bits (inst1, 8, 11); |
| 4375 | if (cond == 0x0f) /* 0x0f = SWI */ |
| 4376 | { |
| 4377 | struct gdbarch_tdep *tdep; |
| 4378 | tdep = gdbarch_tdep (gdbarch); |
| 4379 | |
| 4380 | if (tdep->syscall_next_pc != NULL) |
| 4381 | nextpc = tdep->syscall_next_pc (frame); |
| 4382 | |
| 4383 | } |
| 4384 | else if (cond != 0x0f && condition_true (cond, status)) |
| 4385 | nextpc = pc_val + (sbits (inst1, 0, 7) << 1); |
| 4386 | } |
| 4387 | else if ((inst1 & 0xf800) == 0xe000) /* unconditional branch */ |
| 4388 | { |
| 4389 | nextpc = pc_val + (sbits (inst1, 0, 10) << 1); |
| 4390 | } |
| 4391 | else if ((inst1 & 0xe000) == 0xe000) /* 32-bit instruction */ |
| 4392 | { |
| 4393 | unsigned short inst2; |
| 4394 | inst2 = read_memory_unsigned_integer (pc + 2, 2, byte_order_for_code); |
| 4395 | |
| 4396 | /* Default to the next instruction. */ |
| 4397 | nextpc = pc + 4; |
| 4398 | nextpc = MAKE_THUMB_ADDR (nextpc); |
| 4399 | |
| 4400 | if ((inst1 & 0xf800) == 0xf000 && (inst2 & 0x8000) == 0x8000) |
| 4401 | { |
| 4402 | /* Branches and miscellaneous control instructions. */ |
| 4403 | |
| 4404 | if ((inst2 & 0x1000) != 0 || (inst2 & 0xd001) == 0xc000) |
| 4405 | { |
| 4406 | /* B, BL, BLX. */ |
| 4407 | int j1, j2, imm1, imm2; |
| 4408 | |
| 4409 | imm1 = sbits (inst1, 0, 10); |
| 4410 | imm2 = bits (inst2, 0, 10); |
| 4411 | j1 = bit (inst2, 13); |
| 4412 | j2 = bit (inst2, 11); |
| 4413 | |
| 4414 | offset = ((imm1 << 12) + (imm2 << 1)); |
| 4415 | offset ^= ((!j2) << 22) | ((!j1) << 23); |
| 4416 | |
| 4417 | nextpc = pc_val + offset; |
| 4418 | /* For BLX make sure to clear the low bits. */ |
| 4419 | if (bit (inst2, 12) == 0) |
| 4420 | nextpc = nextpc & 0xfffffffc; |
| 4421 | } |
| 4422 | else if (inst1 == 0xf3de && (inst2 & 0xff00) == 0x3f00) |
| 4423 | { |
| 4424 | /* SUBS PC, LR, #imm8. */ |
| 4425 | nextpc = get_frame_register_unsigned (frame, ARM_LR_REGNUM); |
| 4426 | nextpc -= inst2 & 0x00ff; |
| 4427 | } |
| 4428 | else if ((inst2 & 0xd000) == 0x8000 && (inst1 & 0x0380) != 0x0380) |
| 4429 | { |
| 4430 | /* Conditional branch. */ |
| 4431 | if (condition_true (bits (inst1, 6, 9), status)) |
| 4432 | { |
| 4433 | int sign, j1, j2, imm1, imm2; |
| 4434 | |
| 4435 | sign = sbits (inst1, 10, 10); |
| 4436 | imm1 = bits (inst1, 0, 5); |
| 4437 | imm2 = bits (inst2, 0, 10); |
| 4438 | j1 = bit (inst2, 13); |
| 4439 | j2 = bit (inst2, 11); |
| 4440 | |
| 4441 | offset = (sign << 20) + (j2 << 19) + (j1 << 18); |
| 4442 | offset += (imm1 << 12) + (imm2 << 1); |
| 4443 | |
| 4444 | nextpc = pc_val + offset; |
| 4445 | } |
| 4446 | } |
| 4447 | } |
| 4448 | else if ((inst1 & 0xfe50) == 0xe810) |
| 4449 | { |
| 4450 | /* Load multiple or RFE. */ |
| 4451 | int rn, offset, load_pc = 1; |
| 4452 | |
| 4453 | rn = bits (inst1, 0, 3); |
| 4454 | if (bit (inst1, 7) && !bit (inst1, 8)) |
| 4455 | { |
| 4456 | /* LDMIA or POP */ |
| 4457 | if (!bit (inst2, 15)) |
| 4458 | load_pc = 0; |
| 4459 | offset = bitcount (inst2) * 4 - 4; |
| 4460 | } |
| 4461 | else if (!bit (inst1, 7) && bit (inst1, 8)) |
| 4462 | { |
| 4463 | /* LDMDB */ |
| 4464 | if (!bit (inst2, 15)) |
| 4465 | load_pc = 0; |
| 4466 | offset = -4; |
| 4467 | } |
| 4468 | else if (bit (inst1, 7) && bit (inst1, 8)) |
| 4469 | { |
| 4470 | /* RFEIA */ |
| 4471 | offset = 0; |
| 4472 | } |
| 4473 | else if (!bit (inst1, 7) && !bit (inst1, 8)) |
| 4474 | { |
| 4475 | /* RFEDB */ |
| 4476 | offset = -8; |
| 4477 | } |
| 4478 | else |
| 4479 | load_pc = 0; |
| 4480 | |
| 4481 | if (load_pc) |
| 4482 | { |
| 4483 | CORE_ADDR addr = get_frame_register_unsigned (frame, rn); |
| 4484 | nextpc = get_frame_memory_unsigned (frame, addr + offset, 4); |
| 4485 | } |
| 4486 | } |
| 4487 | else if ((inst1 & 0xffef) == 0xea4f && (inst2 & 0xfff0) == 0x0f00) |
| 4488 | { |
| 4489 | /* MOV PC or MOVS PC. */ |
| 4490 | nextpc = get_frame_register_unsigned (frame, bits (inst2, 0, 3)); |
| 4491 | nextpc = MAKE_THUMB_ADDR (nextpc); |
| 4492 | } |
| 4493 | else if ((inst1 & 0xff70) == 0xf850 && (inst2 & 0xf000) == 0xf000) |
| 4494 | { |
| 4495 | /* LDR PC. */ |
| 4496 | CORE_ADDR base; |
| 4497 | int rn, load_pc = 1; |
| 4498 | |
| 4499 | rn = bits (inst1, 0, 3); |
| 4500 | base = get_frame_register_unsigned (frame, rn); |
| 4501 | if (rn == ARM_PC_REGNUM) |
| 4502 | { |
| 4503 | base = (base + 4) & ~(CORE_ADDR) 0x3; |
| 4504 | if (bit (inst1, 7)) |
| 4505 | base += bits (inst2, 0, 11); |
| 4506 | else |
| 4507 | base -= bits (inst2, 0, 11); |
| 4508 | } |
| 4509 | else if (bit (inst1, 7)) |
| 4510 | base += bits (inst2, 0, 11); |
| 4511 | else if (bit (inst2, 11)) |
| 4512 | { |
| 4513 | if (bit (inst2, 10)) |
| 4514 | { |
| 4515 | if (bit (inst2, 9)) |
| 4516 | base += bits (inst2, 0, 7); |
| 4517 | else |
| 4518 | base -= bits (inst2, 0, 7); |
| 4519 | } |
| 4520 | } |
| 4521 | else if ((inst2 & 0x0fc0) == 0x0000) |
| 4522 | { |
| 4523 | int shift = bits (inst2, 4, 5), rm = bits (inst2, 0, 3); |
| 4524 | base += get_frame_register_unsigned (frame, rm) << shift; |
| 4525 | } |
| 4526 | else |
| 4527 | /* Reserved. */ |
| 4528 | load_pc = 0; |
| 4529 | |
| 4530 | if (load_pc) |
| 4531 | nextpc = get_frame_memory_unsigned (frame, base, 4); |
| 4532 | } |
| 4533 | else if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf000) |
| 4534 | { |
| 4535 | /* TBB. */ |
| 4536 | CORE_ADDR tbl_reg, table, offset, length; |
| 4537 | |
| 4538 | tbl_reg = bits (inst1, 0, 3); |
| 4539 | if (tbl_reg == 0x0f) |
| 4540 | table = pc + 4; /* Regcache copy of PC isn't right yet. */ |
| 4541 | else |
| 4542 | table = get_frame_register_unsigned (frame, tbl_reg); |
| 4543 | |
| 4544 | offset = get_frame_register_unsigned (frame, bits (inst2, 0, 3)); |
| 4545 | length = 2 * get_frame_memory_unsigned (frame, table + offset, 1); |
| 4546 | nextpc = pc_val + length; |
| 4547 | } |
| 4548 | else if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf010) |
| 4549 | { |
| 4550 | /* TBH. */ |
| 4551 | CORE_ADDR tbl_reg, table, offset, length; |
| 4552 | |
| 4553 | tbl_reg = bits (inst1, 0, 3); |
| 4554 | if (tbl_reg == 0x0f) |
| 4555 | table = pc + 4; /* Regcache copy of PC isn't right yet. */ |
| 4556 | else |
| 4557 | table = get_frame_register_unsigned (frame, tbl_reg); |
| 4558 | |
| 4559 | offset = 2 * get_frame_register_unsigned (frame, bits (inst2, 0, 3)); |
| 4560 | length = 2 * get_frame_memory_unsigned (frame, table + offset, 2); |
| 4561 | nextpc = pc_val + length; |
| 4562 | } |
| 4563 | } |
| 4564 | else if ((inst1 & 0xff00) == 0x4700) /* bx REG, blx REG */ |
| 4565 | { |
| 4566 | if (bits (inst1, 3, 6) == 0x0f) |
| 4567 | nextpc = pc_val; |
| 4568 | else |
| 4569 | nextpc = get_frame_register_unsigned (frame, bits (inst1, 3, 6)); |
| 4570 | } |
| 4571 | else if ((inst1 & 0xff87) == 0x4687) /* mov pc, REG */ |
| 4572 | { |
| 4573 | if (bits (inst1, 3, 6) == 0x0f) |
| 4574 | nextpc = pc_val; |
| 4575 | else |
| 4576 | nextpc = get_frame_register_unsigned (frame, bits (inst1, 3, 6)); |
| 4577 | |
| 4578 | nextpc = MAKE_THUMB_ADDR (nextpc); |
| 4579 | } |
| 4580 | else if ((inst1 & 0xf500) == 0xb100) |
| 4581 | { |
| 4582 | /* CBNZ or CBZ. */ |
| 4583 | int imm = (bit (inst1, 9) << 6) + (bits (inst1, 3, 7) << 1); |
| 4584 | ULONGEST reg = get_frame_register_unsigned (frame, bits (inst1, 0, 2)); |
| 4585 | |
| 4586 | if (bit (inst1, 11) && reg != 0) |
| 4587 | nextpc = pc_val + imm; |
| 4588 | else if (!bit (inst1, 11) && reg == 0) |
| 4589 | nextpc = pc_val + imm; |
| 4590 | } |
| 4591 | return nextpc; |
| 4592 | } |
| 4593 | |
| 4594 | /* Get the raw next address. PC is the current program counter, in |
| 4595 | FRAME. INSERT_BKPT should be TRUE if we want a breakpoint set on |
| 4596 | the alternative next instruction if there are two options. |
| 4597 | |
| 4598 | The value returned has the execution state of the next instruction |
| 4599 | encoded in it. Use IS_THUMB_ADDR () to see whether the instruction is |
| 4600 | in Thumb-State, and gdbarch_addr_bits_remove () to get the plain memory |
| 4601 | address. */ |
| 4602 | |
| 4603 | static CORE_ADDR |
| 4604 | arm_get_next_pc_raw (struct frame_info *frame, CORE_ADDR pc, int insert_bkpt) |
| 4605 | { |
| 4606 | struct gdbarch *gdbarch = get_frame_arch (frame); |
| 4607 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 4608 | enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch); |
| 4609 | unsigned long pc_val; |
| 4610 | unsigned long this_instr; |
| 4611 | unsigned long status; |
| 4612 | CORE_ADDR nextpc; |
| 4613 | |
| 4614 | if (arm_frame_is_thumb (frame)) |
| 4615 | return thumb_get_next_pc_raw (frame, pc, insert_bkpt); |
| 4616 | |
| 4617 | pc_val = (unsigned long) pc; |
| 4618 | this_instr = read_memory_unsigned_integer (pc, 4, byte_order_for_code); |
| 4619 | |
| 4620 | status = get_frame_register_unsigned (frame, ARM_PS_REGNUM); |
| 4621 | nextpc = (CORE_ADDR) (pc_val + 4); /* Default case */ |
| 4622 | |
| 4623 | if (bits (this_instr, 28, 31) == INST_NV) |
| 4624 | switch (bits (this_instr, 24, 27)) |
| 4625 | { |
| 4626 | case 0xa: |
| 4627 | case 0xb: |
| 4628 | { |
| 4629 | /* Branch with Link and change to Thumb. */ |
| 4630 | nextpc = BranchDest (pc, this_instr); |
| 4631 | nextpc |= bit (this_instr, 24) << 1; |
| 4632 | nextpc = MAKE_THUMB_ADDR (nextpc); |
| 4633 | break; |
| 4634 | } |
| 4635 | case 0xc: |
| 4636 | case 0xd: |
| 4637 | case 0xe: |
| 4638 | /* Coprocessor register transfer. */ |
| 4639 | if (bits (this_instr, 12, 15) == 15) |
| 4640 | error (_("Invalid update to pc in instruction")); |
| 4641 | break; |
| 4642 | } |
| 4643 | else if (condition_true (bits (this_instr, 28, 31), status)) |
| 4644 | { |
| 4645 | switch (bits (this_instr, 24, 27)) |
| 4646 | { |
| 4647 | case 0x0: |
| 4648 | case 0x1: /* data processing */ |
| 4649 | case 0x2: |
| 4650 | case 0x3: |
| 4651 | { |
| 4652 | unsigned long operand1, operand2, result = 0; |
| 4653 | unsigned long rn; |
| 4654 | int c; |
| 4655 | |
| 4656 | if (bits (this_instr, 12, 15) != 15) |
| 4657 | break; |
| 4658 | |
| 4659 | if (bits (this_instr, 22, 25) == 0 |
| 4660 | && bits (this_instr, 4, 7) == 9) /* multiply */ |
| 4661 | error (_("Invalid update to pc in instruction")); |
| 4662 | |
| 4663 | /* BX <reg>, BLX <reg> */ |
| 4664 | if (bits (this_instr, 4, 27) == 0x12fff1 |
| 4665 | || bits (this_instr, 4, 27) == 0x12fff3) |
| 4666 | { |
| 4667 | rn = bits (this_instr, 0, 3); |
| 4668 | nextpc = ((rn == ARM_PC_REGNUM) |
| 4669 | ? (pc_val + 8) |
| 4670 | : get_frame_register_unsigned (frame, rn)); |
| 4671 | |
| 4672 | return nextpc; |
| 4673 | } |
| 4674 | |
| 4675 | /* Multiply into PC. */ |
| 4676 | c = (status & FLAG_C) ? 1 : 0; |
| 4677 | rn = bits (this_instr, 16, 19); |
| 4678 | operand1 = ((rn == ARM_PC_REGNUM) |
| 4679 | ? (pc_val + 8) |
| 4680 | : get_frame_register_unsigned (frame, rn)); |
| 4681 | |
| 4682 | if (bit (this_instr, 25)) |
| 4683 | { |
| 4684 | unsigned long immval = bits (this_instr, 0, 7); |
| 4685 | unsigned long rotate = 2 * bits (this_instr, 8, 11); |
| 4686 | operand2 = ((immval >> rotate) | (immval << (32 - rotate))) |
| 4687 | & 0xffffffff; |
| 4688 | } |
| 4689 | else /* operand 2 is a shifted register. */ |
| 4690 | operand2 = shifted_reg_val (frame, this_instr, c, |
| 4691 | pc_val, status); |
| 4692 | |
| 4693 | switch (bits (this_instr, 21, 24)) |
| 4694 | { |
| 4695 | case 0x0: /*and */ |
| 4696 | result = operand1 & operand2; |
| 4697 | break; |
| 4698 | |
| 4699 | case 0x1: /*eor */ |
| 4700 | result = operand1 ^ operand2; |
| 4701 | break; |
| 4702 | |
| 4703 | case 0x2: /*sub */ |
| 4704 | result = operand1 - operand2; |
| 4705 | break; |
| 4706 | |
| 4707 | case 0x3: /*rsb */ |
| 4708 | result = operand2 - operand1; |
| 4709 | break; |
| 4710 | |
| 4711 | case 0x4: /*add */ |
| 4712 | result = operand1 + operand2; |
| 4713 | break; |
| 4714 | |
| 4715 | case 0x5: /*adc */ |
| 4716 | result = operand1 + operand2 + c; |
| 4717 | break; |
| 4718 | |
| 4719 | case 0x6: /*sbc */ |
| 4720 | result = operand1 - operand2 + c; |
| 4721 | break; |
| 4722 | |
| 4723 | case 0x7: /*rsc */ |
| 4724 | result = operand2 - operand1 + c; |
| 4725 | break; |
| 4726 | |
| 4727 | case 0x8: |
| 4728 | case 0x9: |
| 4729 | case 0xa: |
| 4730 | case 0xb: /* tst, teq, cmp, cmn */ |
| 4731 | result = (unsigned long) nextpc; |
| 4732 | break; |
| 4733 | |
| 4734 | case 0xc: /*orr */ |
| 4735 | result = operand1 | operand2; |
| 4736 | break; |
| 4737 | |
| 4738 | case 0xd: /*mov */ |
| 4739 | /* Always step into a function. */ |
| 4740 | result = operand2; |
| 4741 | break; |
| 4742 | |
| 4743 | case 0xe: /*bic */ |
| 4744 | result = operand1 & ~operand2; |
| 4745 | break; |
| 4746 | |
| 4747 | case 0xf: /*mvn */ |
| 4748 | result = ~operand2; |
| 4749 | break; |
| 4750 | } |
| 4751 | |
| 4752 | /* In 26-bit APCS the bottom two bits of the result are |
| 4753 | ignored, and we always end up in ARM state. */ |
| 4754 | if (!arm_apcs_32) |
| 4755 | nextpc = arm_addr_bits_remove (gdbarch, result); |
| 4756 | else |
| 4757 | nextpc = result; |
| 4758 | |
| 4759 | break; |
| 4760 | } |
| 4761 | |
| 4762 | case 0x4: |
| 4763 | case 0x5: /* data transfer */ |
| 4764 | case 0x6: |
| 4765 | case 0x7: |
| 4766 | if (bit (this_instr, 20)) |
| 4767 | { |
| 4768 | /* load */ |
| 4769 | if (bits (this_instr, 12, 15) == 15) |
| 4770 | { |
| 4771 | /* rd == pc */ |
| 4772 | unsigned long rn; |
| 4773 | unsigned long base; |
| 4774 | |
| 4775 | if (bit (this_instr, 22)) |
| 4776 | error (_("Invalid update to pc in instruction")); |
| 4777 | |
| 4778 | /* byte write to PC */ |
| 4779 | rn = bits (this_instr, 16, 19); |
| 4780 | base = ((rn == ARM_PC_REGNUM) |
| 4781 | ? (pc_val + 8) |
| 4782 | : get_frame_register_unsigned (frame, rn)); |
| 4783 | |
| 4784 | if (bit (this_instr, 24)) |
| 4785 | { |
| 4786 | /* pre-indexed */ |
| 4787 | int c = (status & FLAG_C) ? 1 : 0; |
| 4788 | unsigned long offset = |
| 4789 | (bit (this_instr, 25) |
| 4790 | ? shifted_reg_val (frame, this_instr, c, pc_val, status) |
| 4791 | : bits (this_instr, 0, 11)); |
| 4792 | |
| 4793 | if (bit (this_instr, 23)) |
| 4794 | base += offset; |
| 4795 | else |
| 4796 | base -= offset; |
| 4797 | } |
| 4798 | nextpc = (CORE_ADDR) read_memory_integer ((CORE_ADDR) base, |
| 4799 | 4, byte_order); |
| 4800 | } |
| 4801 | } |
| 4802 | break; |
| 4803 | |
| 4804 | case 0x8: |
| 4805 | case 0x9: /* block transfer */ |
| 4806 | if (bit (this_instr, 20)) |
| 4807 | { |
| 4808 | /* LDM */ |
| 4809 | if (bit (this_instr, 15)) |
| 4810 | { |
| 4811 | /* loading pc */ |
| 4812 | int offset = 0; |
| 4813 | |
| 4814 | if (bit (this_instr, 23)) |
| 4815 | { |
| 4816 | /* up */ |
| 4817 | unsigned long reglist = bits (this_instr, 0, 14); |
| 4818 | offset = bitcount (reglist) * 4; |
| 4819 | if (bit (this_instr, 24)) /* pre */ |
| 4820 | offset += 4; |
| 4821 | } |
| 4822 | else if (bit (this_instr, 24)) |
| 4823 | offset = -4; |
| 4824 | |
| 4825 | { |
| 4826 | unsigned long rn_val = |
| 4827 | get_frame_register_unsigned (frame, |
| 4828 | bits (this_instr, 16, 19)); |
| 4829 | nextpc = |
| 4830 | (CORE_ADDR) read_memory_integer ((CORE_ADDR) (rn_val |
| 4831 | + offset), |
| 4832 | 4, byte_order); |
| 4833 | } |
| 4834 | } |
| 4835 | } |
| 4836 | break; |
| 4837 | |
| 4838 | case 0xb: /* branch & link */ |
| 4839 | case 0xa: /* branch */ |
| 4840 | { |
| 4841 | nextpc = BranchDest (pc, this_instr); |
| 4842 | break; |
| 4843 | } |
| 4844 | |
| 4845 | case 0xc: |
| 4846 | case 0xd: |
| 4847 | case 0xe: /* coproc ops */ |
| 4848 | break; |
| 4849 | case 0xf: /* SWI */ |
| 4850 | { |
| 4851 | struct gdbarch_tdep *tdep; |
| 4852 | tdep = gdbarch_tdep (gdbarch); |
| 4853 | |
| 4854 | if (tdep->syscall_next_pc != NULL) |
| 4855 | nextpc = tdep->syscall_next_pc (frame); |
| 4856 | |
| 4857 | } |
| 4858 | break; |
| 4859 | |
| 4860 | default: |
| 4861 | fprintf_filtered (gdb_stderr, _("Bad bit-field extraction\n")); |
| 4862 | return (pc); |
| 4863 | } |
| 4864 | } |
| 4865 | |
| 4866 | return nextpc; |
| 4867 | } |
| 4868 | |
| 4869 | CORE_ADDR |
| 4870 | arm_get_next_pc (struct frame_info *frame, CORE_ADDR pc) |
| 4871 | { |
| 4872 | struct gdbarch *gdbarch = get_frame_arch (frame); |
| 4873 | CORE_ADDR nextpc = |
| 4874 | gdbarch_addr_bits_remove (gdbarch, |
| 4875 | arm_get_next_pc_raw (frame, pc, TRUE)); |
| 4876 | if (nextpc == pc) |
| 4877 | error (_("Infinite loop detected")); |
| 4878 | return nextpc; |
| 4879 | } |
| 4880 | |
| 4881 | /* single_step() is called just before we want to resume the inferior, |
| 4882 | if we want to single-step it but there is no hardware or kernel |
| 4883 | single-step support. We find the target of the coming instruction |
| 4884 | and breakpoint it. */ |
| 4885 | |
| 4886 | int |
| 4887 | arm_software_single_step (struct frame_info *frame) |
| 4888 | { |
| 4889 | struct gdbarch *gdbarch = get_frame_arch (frame); |
| 4890 | struct address_space *aspace = get_frame_address_space (frame); |
| 4891 | |
| 4892 | /* NOTE: This may insert the wrong breakpoint instruction when |
| 4893 | single-stepping over a mode-changing instruction, if the |
| 4894 | CPSR heuristics are used. */ |
| 4895 | |
| 4896 | CORE_ADDR next_pc = arm_get_next_pc (frame, get_frame_pc (frame)); |
| 4897 | insert_single_step_breakpoint (gdbarch, aspace, next_pc); |
| 4898 | |
| 4899 | return 1; |
| 4900 | } |
| 4901 | |
| 4902 | /* Given BUF, which is OLD_LEN bytes ending at ENDADDR, expand |
| 4903 | the buffer to be NEW_LEN bytes ending at ENDADDR. Return |
| 4904 | NULL if an error occurs. BUF is freed. */ |
| 4905 | |
| 4906 | static gdb_byte * |
| 4907 | extend_buffer_earlier (gdb_byte *buf, CORE_ADDR endaddr, |
| 4908 | int old_len, int new_len) |
| 4909 | { |
| 4910 | gdb_byte *new_buf, *middle; |
| 4911 | int bytes_to_read = new_len - old_len; |
| 4912 | |
| 4913 | new_buf = xmalloc (new_len); |
| 4914 | memcpy (new_buf + bytes_to_read, buf, old_len); |
| 4915 | xfree (buf); |
| 4916 | if (target_read_memory (endaddr - new_len, new_buf, bytes_to_read) != 0) |
| 4917 | { |
| 4918 | xfree (new_buf); |
| 4919 | return NULL; |
| 4920 | } |
| 4921 | return new_buf; |
| 4922 | } |
| 4923 | |
| 4924 | /* An IT block is at most the 2-byte IT instruction followed by |
| 4925 | four 4-byte instructions. The furthest back we must search to |
| 4926 | find an IT block that affects the current instruction is thus |
| 4927 | 2 + 3 * 4 == 14 bytes. */ |
| 4928 | #define MAX_IT_BLOCK_PREFIX 14 |
| 4929 | |
| 4930 | /* Use a quick scan if there are more than this many bytes of |
| 4931 | code. */ |
| 4932 | #define IT_SCAN_THRESHOLD 32 |
| 4933 | |
| 4934 | /* Adjust a breakpoint's address to move breakpoints out of IT blocks. |
| 4935 | A breakpoint in an IT block may not be hit, depending on the |
| 4936 | condition flags. */ |
| 4937 | static CORE_ADDR |
| 4938 | arm_adjust_breakpoint_address (struct gdbarch *gdbarch, CORE_ADDR bpaddr) |
| 4939 | { |
| 4940 | gdb_byte *buf; |
| 4941 | char map_type; |
| 4942 | CORE_ADDR boundary, func_start; |
| 4943 | int buf_len, buf2_len; |
| 4944 | enum bfd_endian order = gdbarch_byte_order_for_code (gdbarch); |
| 4945 | int i, any, last_it, last_it_count; |
| 4946 | |
| 4947 | /* If we are using BKPT breakpoints, none of this is necessary. */ |
| 4948 | if (gdbarch_tdep (gdbarch)->thumb2_breakpoint == NULL) |
| 4949 | return bpaddr; |
| 4950 | |
| 4951 | /* ARM mode does not have this problem. */ |
| 4952 | if (!arm_pc_is_thumb (gdbarch, bpaddr)) |
| 4953 | return bpaddr; |
| 4954 | |
| 4955 | /* We are setting a breakpoint in Thumb code that could potentially |
| 4956 | contain an IT block. The first step is to find how much Thumb |
| 4957 | code there is; we do not need to read outside of known Thumb |
| 4958 | sequences. */ |
| 4959 | map_type = arm_find_mapping_symbol (bpaddr, &boundary); |
| 4960 | if (map_type == 0) |
| 4961 | /* Thumb-2 code must have mapping symbols to have a chance. */ |
| 4962 | return bpaddr; |
| 4963 | |
| 4964 | bpaddr = gdbarch_addr_bits_remove (gdbarch, bpaddr); |
| 4965 | |
| 4966 | if (find_pc_partial_function (bpaddr, NULL, &func_start, NULL) |
| 4967 | && func_start > boundary) |
| 4968 | boundary = func_start; |
| 4969 | |
| 4970 | /* Search for a candidate IT instruction. We have to do some fancy |
| 4971 | footwork to distinguish a real IT instruction from the second |
| 4972 | half of a 32-bit instruction, but there is no need for that if |
| 4973 | there's no candidate. */ |
| 4974 | buf_len = min (bpaddr - boundary, MAX_IT_BLOCK_PREFIX); |
| 4975 | if (buf_len == 0) |
| 4976 | /* No room for an IT instruction. */ |
| 4977 | return bpaddr; |
| 4978 | |
| 4979 | buf = xmalloc (buf_len); |
| 4980 | if (target_read_memory (bpaddr - buf_len, buf, buf_len) != 0) |
| 4981 | return bpaddr; |
| 4982 | any = 0; |
| 4983 | for (i = 0; i < buf_len; i += 2) |
| 4984 | { |
| 4985 | unsigned short inst1 = extract_unsigned_integer (&buf[i], 2, order); |
| 4986 | if ((inst1 & 0xff00) == 0xbf00 && (inst1 & 0x000f) != 0) |
| 4987 | { |
| 4988 | any = 1; |
| 4989 | break; |
| 4990 | } |
| 4991 | } |
| 4992 | if (any == 0) |
| 4993 | { |
| 4994 | xfree (buf); |
| 4995 | return bpaddr; |
| 4996 | } |
| 4997 | |
| 4998 | /* OK, the code bytes before this instruction contain at least one |
| 4999 | halfword which resembles an IT instruction. We know that it's |
| 5000 | Thumb code, but there are still two possibilities. Either the |
| 5001 | halfword really is an IT instruction, or it is the second half of |
| 5002 | a 32-bit Thumb instruction. The only way we can tell is to |
| 5003 | scan forwards from a known instruction boundary. */ |
| 5004 | if (bpaddr - boundary > IT_SCAN_THRESHOLD) |
| 5005 | { |
| 5006 | int definite; |
| 5007 | |
| 5008 | /* There's a lot of code before this instruction. Start with an |
| 5009 | optimistic search; it's easy to recognize halfwords that can |
| 5010 | not be the start of a 32-bit instruction, and use that to |
| 5011 | lock on to the instruction boundaries. */ |
| 5012 | buf = extend_buffer_earlier (buf, bpaddr, buf_len, IT_SCAN_THRESHOLD); |
| 5013 | if (buf == NULL) |
| 5014 | return bpaddr; |
| 5015 | buf_len = IT_SCAN_THRESHOLD; |
| 5016 | |
| 5017 | definite = 0; |
| 5018 | for (i = 0; i < buf_len - sizeof (buf) && ! definite; i += 2) |
| 5019 | { |
| 5020 | unsigned short inst1 = extract_unsigned_integer (&buf[i], 2, order); |
| 5021 | if (thumb_insn_size (inst1) == 2) |
| 5022 | { |
| 5023 | definite = 1; |
| 5024 | break; |
| 5025 | } |
| 5026 | } |
| 5027 | |
| 5028 | /* At this point, if DEFINITE, BUF[I] is the first place we |
| 5029 | are sure that we know the instruction boundaries, and it is far |
| 5030 | enough from BPADDR that we could not miss an IT instruction |
| 5031 | affecting BPADDR. If ! DEFINITE, give up - start from a |
| 5032 | known boundary. */ |
| 5033 | if (! definite) |
| 5034 | { |
| 5035 | buf = extend_buffer_earlier (buf, bpaddr, buf_len, |
| 5036 | bpaddr - boundary); |
| 5037 | if (buf == NULL) |
| 5038 | return bpaddr; |
| 5039 | buf_len = bpaddr - boundary; |
| 5040 | i = 0; |
| 5041 | } |
| 5042 | } |
| 5043 | else |
| 5044 | { |
| 5045 | buf = extend_buffer_earlier (buf, bpaddr, buf_len, bpaddr - boundary); |
| 5046 | if (buf == NULL) |
| 5047 | return bpaddr; |
| 5048 | buf_len = bpaddr - boundary; |
| 5049 | i = 0; |
| 5050 | } |
| 5051 | |
| 5052 | /* Scan forwards. Find the last IT instruction before BPADDR. */ |
| 5053 | last_it = -1; |
| 5054 | last_it_count = 0; |
| 5055 | while (i < buf_len) |
| 5056 | { |
| 5057 | unsigned short inst1 = extract_unsigned_integer (&buf[i], 2, order); |
| 5058 | last_it_count--; |
| 5059 | if ((inst1 & 0xff00) == 0xbf00 && (inst1 & 0x000f) != 0) |
| 5060 | { |
| 5061 | last_it = i; |
| 5062 | if (inst1 & 0x0001) |
| 5063 | last_it_count = 4; |
| 5064 | else if (inst1 & 0x0002) |
| 5065 | last_it_count = 3; |
| 5066 | else if (inst1 & 0x0004) |
| 5067 | last_it_count = 2; |
| 5068 | else |
| 5069 | last_it_count = 1; |
| 5070 | } |
| 5071 | i += thumb_insn_size (inst1); |
| 5072 | } |
| 5073 | |
| 5074 | xfree (buf); |
| 5075 | |
| 5076 | if (last_it == -1) |
| 5077 | /* There wasn't really an IT instruction after all. */ |
| 5078 | return bpaddr; |
| 5079 | |
| 5080 | if (last_it_count < 1) |
| 5081 | /* It was too far away. */ |
| 5082 | return bpaddr; |
| 5083 | |
| 5084 | /* This really is a trouble spot. Move the breakpoint to the IT |
| 5085 | instruction. */ |
| 5086 | return bpaddr - buf_len + last_it; |
| 5087 | } |
| 5088 | |
| 5089 | /* ARM displaced stepping support. |
| 5090 | |
| 5091 | Generally ARM displaced stepping works as follows: |
| 5092 | |
| 5093 | 1. When an instruction is to be single-stepped, it is first decoded by |
| 5094 | arm_process_displaced_insn (called from arm_displaced_step_copy_insn). |
| 5095 | Depending on the type of instruction, it is then copied to a scratch |
| 5096 | location, possibly in a modified form. The copy_* set of functions |
| 5097 | performs such modification, as necessary. A breakpoint is placed after |
| 5098 | the modified instruction in the scratch space to return control to GDB. |
| 5099 | Note in particular that instructions which modify the PC will no longer |
| 5100 | do so after modification. |
| 5101 | |
| 5102 | 2. The instruction is single-stepped, by setting the PC to the scratch |
| 5103 | location address, and resuming. Control returns to GDB when the |
| 5104 | breakpoint is hit. |
| 5105 | |
| 5106 | 3. A cleanup function (cleanup_*) is called corresponding to the copy_* |
| 5107 | function used for the current instruction. This function's job is to |
| 5108 | put the CPU/memory state back to what it would have been if the |
| 5109 | instruction had been executed unmodified in its original location. */ |
| 5110 | |
| 5111 | /* NOP instruction (mov r0, r0). */ |
| 5112 | #define ARM_NOP 0xe1a00000 |
| 5113 | |
| 5114 | /* Helper for register reads for displaced stepping. In particular, this |
| 5115 | returns the PC as it would be seen by the instruction at its original |
| 5116 | location. */ |
| 5117 | |
| 5118 | ULONGEST |
| 5119 | displaced_read_reg (struct regcache *regs, struct displaced_step_closure *dsc, |
| 5120 | int regno) |
| 5121 | { |
| 5122 | ULONGEST ret; |
| 5123 | CORE_ADDR from = dsc->insn_addr; |
| 5124 | |
| 5125 | if (regno == ARM_PC_REGNUM) |
| 5126 | { |
| 5127 | /* Compute pipeline offset: |
| 5128 | - When executing an ARM instruction, PC reads as the address of the |
| 5129 | current instruction plus 8. |
| 5130 | - When executing a Thumb instruction, PC reads as the address of the |
| 5131 | current instruction plus 4. */ |
| 5132 | |
| 5133 | if (!dsc->is_thumb) |
| 5134 | from += 8; |
| 5135 | else |
| 5136 | from += 4; |
| 5137 | |
| 5138 | if (debug_displaced) |
| 5139 | fprintf_unfiltered (gdb_stdlog, "displaced: read pc value %.8lx\n", |
| 5140 | (unsigned long) from); |
| 5141 | return (ULONGEST) from; |
| 5142 | } |
| 5143 | else |
| 5144 | { |
| 5145 | regcache_cooked_read_unsigned (regs, regno, &ret); |
| 5146 | if (debug_displaced) |
| 5147 | fprintf_unfiltered (gdb_stdlog, "displaced: read r%d value %.8lx\n", |
| 5148 | regno, (unsigned long) ret); |
| 5149 | return ret; |
| 5150 | } |
| 5151 | } |
| 5152 | |
| 5153 | static int |
| 5154 | displaced_in_arm_mode (struct regcache *regs) |
| 5155 | { |
| 5156 | ULONGEST ps; |
| 5157 | ULONGEST t_bit = arm_psr_thumb_bit (get_regcache_arch (regs)); |
| 5158 | |
| 5159 | regcache_cooked_read_unsigned (regs, ARM_PS_REGNUM, &ps); |
| 5160 | |
| 5161 | return (ps & t_bit) == 0; |
| 5162 | } |
| 5163 | |
| 5164 | /* Write to the PC as from a branch instruction. */ |
| 5165 | |
| 5166 | static void |
| 5167 | branch_write_pc (struct regcache *regs, struct displaced_step_closure *dsc, |
| 5168 | ULONGEST val) |
| 5169 | { |
| 5170 | if (!dsc->is_thumb) |
| 5171 | /* Note: If bits 0/1 are set, this branch would be unpredictable for |
| 5172 | architecture versions < 6. */ |
| 5173 | regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, |
| 5174 | val & ~(ULONGEST) 0x3); |
| 5175 | else |
| 5176 | regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, |
| 5177 | val & ~(ULONGEST) 0x1); |
| 5178 | } |
| 5179 | |
| 5180 | /* Write to the PC as from a branch-exchange instruction. */ |
| 5181 | |
| 5182 | static void |
| 5183 | bx_write_pc (struct regcache *regs, ULONGEST val) |
| 5184 | { |
| 5185 | ULONGEST ps; |
| 5186 | ULONGEST t_bit = arm_psr_thumb_bit (get_regcache_arch (regs)); |
| 5187 | |
| 5188 | regcache_cooked_read_unsigned (regs, ARM_PS_REGNUM, &ps); |
| 5189 | |
| 5190 | if ((val & 1) == 1) |
| 5191 | { |
| 5192 | regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM, ps | t_bit); |
| 5193 | regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val & 0xfffffffe); |
| 5194 | } |
| 5195 | else if ((val & 2) == 0) |
| 5196 | { |
| 5197 | regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM, ps & ~t_bit); |
| 5198 | regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val); |
| 5199 | } |
| 5200 | else |
| 5201 | { |
| 5202 | /* Unpredictable behaviour. Try to do something sensible (switch to ARM |
| 5203 | mode, align dest to 4 bytes). */ |
| 5204 | warning (_("Single-stepping BX to non-word-aligned ARM instruction.")); |
| 5205 | regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM, ps & ~t_bit); |
| 5206 | regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val & 0xfffffffc); |
| 5207 | } |
| 5208 | } |
| 5209 | |
| 5210 | /* Write to the PC as if from a load instruction. */ |
| 5211 | |
| 5212 | static void |
| 5213 | load_write_pc (struct regcache *regs, struct displaced_step_closure *dsc, |
| 5214 | ULONGEST val) |
| 5215 | { |
| 5216 | if (DISPLACED_STEPPING_ARCH_VERSION >= 5) |
| 5217 | bx_write_pc (regs, val); |
| 5218 | else |
| 5219 | branch_write_pc (regs, dsc, val); |
| 5220 | } |
| 5221 | |
| 5222 | /* Write to the PC as if from an ALU instruction. */ |
| 5223 | |
| 5224 | static void |
| 5225 | alu_write_pc (struct regcache *regs, struct displaced_step_closure *dsc, |
| 5226 | ULONGEST val) |
| 5227 | { |
| 5228 | if (DISPLACED_STEPPING_ARCH_VERSION >= 7 && !dsc->is_thumb) |
| 5229 | bx_write_pc (regs, val); |
| 5230 | else |
| 5231 | branch_write_pc (regs, dsc, val); |
| 5232 | } |
| 5233 | |
| 5234 | /* Helper for writing to registers for displaced stepping. Writing to the PC |
| 5235 | has a varying effects depending on the instruction which does the write: |
| 5236 | this is controlled by the WRITE_PC argument. */ |
| 5237 | |
| 5238 | void |
| 5239 | displaced_write_reg (struct regcache *regs, struct displaced_step_closure *dsc, |
| 5240 | int regno, ULONGEST val, enum pc_write_style write_pc) |
| 5241 | { |
| 5242 | if (regno == ARM_PC_REGNUM) |
| 5243 | { |
| 5244 | if (debug_displaced) |
| 5245 | fprintf_unfiltered (gdb_stdlog, "displaced: writing pc %.8lx\n", |
| 5246 | (unsigned long) val); |
| 5247 | switch (write_pc) |
| 5248 | { |
| 5249 | case BRANCH_WRITE_PC: |
| 5250 | branch_write_pc (regs, dsc, val); |
| 5251 | break; |
| 5252 | |
| 5253 | case BX_WRITE_PC: |
| 5254 | bx_write_pc (regs, val); |
| 5255 | break; |
| 5256 | |
| 5257 | case LOAD_WRITE_PC: |
| 5258 | load_write_pc (regs, dsc, val); |
| 5259 | break; |
| 5260 | |
| 5261 | case ALU_WRITE_PC: |
| 5262 | alu_write_pc (regs, dsc, val); |
| 5263 | break; |
| 5264 | |
| 5265 | case CANNOT_WRITE_PC: |
| 5266 | warning (_("Instruction wrote to PC in an unexpected way when " |
| 5267 | "single-stepping")); |
| 5268 | break; |
| 5269 | |
| 5270 | default: |
| 5271 | internal_error (__FILE__, __LINE__, |
| 5272 | _("Invalid argument to displaced_write_reg")); |
| 5273 | } |
| 5274 | |
| 5275 | dsc->wrote_to_pc = 1; |
| 5276 | } |
| 5277 | else |
| 5278 | { |
| 5279 | if (debug_displaced) |
| 5280 | fprintf_unfiltered (gdb_stdlog, "displaced: writing r%d value %.8lx\n", |
| 5281 | regno, (unsigned long) val); |
| 5282 | regcache_cooked_write_unsigned (regs, regno, val); |
| 5283 | } |
| 5284 | } |
| 5285 | |
| 5286 | /* This function is used to concisely determine if an instruction INSN |
| 5287 | references PC. Register fields of interest in INSN should have the |
| 5288 | corresponding fields of BITMASK set to 0b1111. The function |
| 5289 | returns return 1 if any of these fields in INSN reference the PC |
| 5290 | (also 0b1111, r15), else it returns 0. */ |
| 5291 | |
| 5292 | static int |
| 5293 | insn_references_pc (uint32_t insn, uint32_t bitmask) |
| 5294 | { |
| 5295 | uint32_t lowbit = 1; |
| 5296 | |
| 5297 | while (bitmask != 0) |
| 5298 | { |
| 5299 | uint32_t mask; |
| 5300 | |
| 5301 | for (; lowbit && (bitmask & lowbit) == 0; lowbit <<= 1) |
| 5302 | ; |
| 5303 | |
| 5304 | if (!lowbit) |
| 5305 | break; |
| 5306 | |
| 5307 | mask = lowbit * 0xf; |
| 5308 | |
| 5309 | if ((insn & mask) == mask) |
| 5310 | return 1; |
| 5311 | |
| 5312 | bitmask &= ~mask; |
| 5313 | } |
| 5314 | |
| 5315 | return 0; |
| 5316 | } |
| 5317 | |
| 5318 | /* The simplest copy function. Many instructions have the same effect no |
| 5319 | matter what address they are executed at: in those cases, use this. */ |
| 5320 | |
| 5321 | static int |
| 5322 | copy_unmodified (struct gdbarch *gdbarch, uint32_t insn, |
| 5323 | const char *iname, struct displaced_step_closure *dsc) |
| 5324 | { |
| 5325 | if (debug_displaced) |
| 5326 | fprintf_unfiltered (gdb_stdlog, "displaced: copying insn %.8lx, " |
| 5327 | "opcode/class '%s' unmodified\n", (unsigned long) insn, |
| 5328 | iname); |
| 5329 | |
| 5330 | dsc->modinsn[0] = insn; |
| 5331 | |
| 5332 | return 0; |
| 5333 | } |
| 5334 | |
| 5335 | /* Preload instructions with immediate offset. */ |
| 5336 | |
| 5337 | static void |
| 5338 | cleanup_preload (struct gdbarch *gdbarch, |
| 5339 | struct regcache *regs, struct displaced_step_closure *dsc) |
| 5340 | { |
| 5341 | displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC); |
| 5342 | if (!dsc->u.preload.immed) |
| 5343 | displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC); |
| 5344 | } |
| 5345 | |
| 5346 | static int |
| 5347 | copy_preload (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs, |
| 5348 | struct displaced_step_closure *dsc) |
| 5349 | { |
| 5350 | unsigned int rn = bits (insn, 16, 19); |
| 5351 | ULONGEST rn_val; |
| 5352 | |
| 5353 | if (!insn_references_pc (insn, 0x000f0000ul)) |
| 5354 | return copy_unmodified (gdbarch, insn, "preload", dsc); |
| 5355 | |
| 5356 | if (debug_displaced) |
| 5357 | fprintf_unfiltered (gdb_stdlog, "displaced: copying preload insn %.8lx\n", |
| 5358 | (unsigned long) insn); |
| 5359 | |
| 5360 | /* Preload instructions: |
| 5361 | |
| 5362 | {pli/pld} [rn, #+/-imm] |
| 5363 | -> |
| 5364 | {pli/pld} [r0, #+/-imm]. */ |
| 5365 | |
| 5366 | dsc->tmp[0] = displaced_read_reg (regs, dsc, 0); |
| 5367 | rn_val = displaced_read_reg (regs, dsc, rn); |
| 5368 | displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC); |
| 5369 | |
| 5370 | dsc->u.preload.immed = 1; |
| 5371 | |
| 5372 | dsc->modinsn[0] = insn & 0xfff0ffff; |
| 5373 | |
| 5374 | dsc->cleanup = &cleanup_preload; |
| 5375 | |
| 5376 | return 0; |
| 5377 | } |
| 5378 | |
| 5379 | /* Preload instructions with register offset. */ |
| 5380 | |
| 5381 | static int |
| 5382 | copy_preload_reg (struct gdbarch *gdbarch, uint32_t insn, |
| 5383 | struct regcache *regs, |
| 5384 | struct displaced_step_closure *dsc) |
| 5385 | { |
| 5386 | unsigned int rn = bits (insn, 16, 19); |
| 5387 | unsigned int rm = bits (insn, 0, 3); |
| 5388 | ULONGEST rn_val, rm_val; |
| 5389 | |
| 5390 | if (!insn_references_pc (insn, 0x000f000ful)) |
| 5391 | return copy_unmodified (gdbarch, insn, "preload reg", dsc); |
| 5392 | |
| 5393 | if (debug_displaced) |
| 5394 | fprintf_unfiltered (gdb_stdlog, "displaced: copying preload insn %.8lx\n", |
| 5395 | (unsigned long) insn); |
| 5396 | |
| 5397 | /* Preload register-offset instructions: |
| 5398 | |
| 5399 | {pli/pld} [rn, rm {, shift}] |
| 5400 | -> |
| 5401 | {pli/pld} [r0, r1 {, shift}]. */ |
| 5402 | |
| 5403 | dsc->tmp[0] = displaced_read_reg (regs, dsc, 0); |
| 5404 | dsc->tmp[1] = displaced_read_reg (regs, dsc, 1); |
| 5405 | rn_val = displaced_read_reg (regs, dsc, rn); |
| 5406 | rm_val = displaced_read_reg (regs, dsc, rm); |
| 5407 | displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC); |
| 5408 | displaced_write_reg (regs, dsc, 1, rm_val, CANNOT_WRITE_PC); |
| 5409 | |
| 5410 | dsc->u.preload.immed = 0; |
| 5411 | |
| 5412 | dsc->modinsn[0] = (insn & 0xfff0fff0) | 0x1; |
| 5413 | |
| 5414 | dsc->cleanup = &cleanup_preload; |
| 5415 | |
| 5416 | return 0; |
| 5417 | } |
| 5418 | |
| 5419 | /* Copy/cleanup coprocessor load and store instructions. */ |
| 5420 | |
| 5421 | static void |
| 5422 | cleanup_copro_load_store (struct gdbarch *gdbarch, |
| 5423 | struct regcache *regs, |
| 5424 | struct displaced_step_closure *dsc) |
| 5425 | { |
| 5426 | ULONGEST rn_val = displaced_read_reg (regs, dsc, 0); |
| 5427 | |
| 5428 | displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC); |
| 5429 | |
| 5430 | if (dsc->u.ldst.writeback) |
| 5431 | displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, LOAD_WRITE_PC); |
| 5432 | } |
| 5433 | |
| 5434 | static int |
| 5435 | copy_copro_load_store (struct gdbarch *gdbarch, uint32_t insn, |
| 5436 | struct regcache *regs, |
| 5437 | struct displaced_step_closure *dsc) |
| 5438 | { |
| 5439 | unsigned int rn = bits (insn, 16, 19); |
| 5440 | ULONGEST rn_val; |
| 5441 | |
| 5442 | if (!insn_references_pc (insn, 0x000f0000ul)) |
| 5443 | return copy_unmodified (gdbarch, insn, "copro load/store", dsc); |
| 5444 | |
| 5445 | if (debug_displaced) |
| 5446 | fprintf_unfiltered (gdb_stdlog, "displaced: copying coprocessor " |
| 5447 | "load/store insn %.8lx\n", (unsigned long) insn); |
| 5448 | |
| 5449 | /* Coprocessor load/store instructions: |
| 5450 | |
| 5451 | {stc/stc2} [<Rn>, #+/-imm] (and other immediate addressing modes) |
| 5452 | -> |
| 5453 | {stc/stc2} [r0, #+/-imm]. |
| 5454 | |
| 5455 | ldc/ldc2 are handled identically. */ |
| 5456 | |
| 5457 | dsc->tmp[0] = displaced_read_reg (regs, dsc, 0); |
| 5458 | rn_val = displaced_read_reg (regs, dsc, rn); |
| 5459 | displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC); |
| 5460 | |
| 5461 | dsc->u.ldst.writeback = bit (insn, 25); |
| 5462 | dsc->u.ldst.rn = rn; |
| 5463 | |
| 5464 | dsc->modinsn[0] = insn & 0xfff0ffff; |
| 5465 | |
| 5466 | dsc->cleanup = &cleanup_copro_load_store; |
| 5467 | |
| 5468 | return 0; |
| 5469 | } |
| 5470 | |
| 5471 | /* Clean up branch instructions (actually perform the branch, by setting |
| 5472 | PC). */ |
| 5473 | |
| 5474 | static void |
| 5475 | cleanup_branch (struct gdbarch *gdbarch, struct regcache *regs, |
| 5476 | struct displaced_step_closure *dsc) |
| 5477 | { |
| 5478 | uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM); |
| 5479 | int branch_taken = condition_true (dsc->u.branch.cond, status); |
| 5480 | enum pc_write_style write_pc = dsc->u.branch.exchange |
| 5481 | ? BX_WRITE_PC : BRANCH_WRITE_PC; |
| 5482 | |
| 5483 | if (!branch_taken) |
| 5484 | return; |
| 5485 | |
| 5486 | if (dsc->u.branch.link) |
| 5487 | { |
| 5488 | ULONGEST pc = displaced_read_reg (regs, dsc, ARM_PC_REGNUM); |
| 5489 | displaced_write_reg (regs, dsc, ARM_LR_REGNUM, pc - 4, CANNOT_WRITE_PC); |
| 5490 | } |
| 5491 | |
| 5492 | displaced_write_reg (regs, dsc, ARM_PC_REGNUM, dsc->u.branch.dest, write_pc); |
| 5493 | } |
| 5494 | |
| 5495 | /* Copy B/BL/BLX instructions with immediate destinations. */ |
| 5496 | |
| 5497 | static int |
| 5498 | copy_b_bl_blx (struct gdbarch *gdbarch, uint32_t insn, |
| 5499 | struct regcache *regs, struct displaced_step_closure *dsc) |
| 5500 | { |
| 5501 | unsigned int cond = bits (insn, 28, 31); |
| 5502 | int exchange = (cond == 0xf); |
| 5503 | int link = exchange || bit (insn, 24); |
| 5504 | CORE_ADDR from = dsc->insn_addr; |
| 5505 | long offset; |
| 5506 | |
| 5507 | if (debug_displaced) |
| 5508 | fprintf_unfiltered (gdb_stdlog, "displaced: copying %s immediate insn " |
| 5509 | "%.8lx\n", (exchange) ? "blx" : (link) ? "bl" : "b", |
| 5510 | (unsigned long) insn); |
| 5511 | |
| 5512 | /* Implement "BL<cond> <label>" as: |
| 5513 | |
| 5514 | Preparation: cond <- instruction condition |
| 5515 | Insn: mov r0, r0 (nop) |
| 5516 | Cleanup: if (condition true) { r14 <- pc; pc <- label }. |
| 5517 | |
| 5518 | B<cond> similar, but don't set r14 in cleanup. */ |
| 5519 | |
| 5520 | if (exchange) |
| 5521 | /* For BLX, set bit 0 of the destination. The cleanup_branch function will |
| 5522 | then arrange the switch into Thumb mode. */ |
| 5523 | offset = (bits (insn, 0, 23) << 2) | (bit (insn, 24) << 1) | 1; |
| 5524 | else |
| 5525 | offset = bits (insn, 0, 23) << 2; |
| 5526 | |
| 5527 | if (bit (offset, 25)) |
| 5528 | offset = offset | ~0x3ffffff; |
| 5529 | |
| 5530 | dsc->u.branch.cond = cond; |
| 5531 | dsc->u.branch.link = link; |
| 5532 | dsc->u.branch.exchange = exchange; |
| 5533 | dsc->u.branch.dest = from + 8 + offset; |
| 5534 | |
| 5535 | dsc->modinsn[0] = ARM_NOP; |
| 5536 | |
| 5537 | dsc->cleanup = &cleanup_branch; |
| 5538 | |
| 5539 | return 0; |
| 5540 | } |
| 5541 | |
| 5542 | /* Copy BX/BLX with register-specified destinations. */ |
| 5543 | |
| 5544 | static int |
| 5545 | copy_bx_blx_reg (struct gdbarch *gdbarch, uint32_t insn, |
| 5546 | struct regcache *regs, struct displaced_step_closure *dsc) |
| 5547 | { |
| 5548 | unsigned int cond = bits (insn, 28, 31); |
| 5549 | /* BX: x12xxx1x |
| 5550 | BLX: x12xxx3x. */ |
| 5551 | int link = bit (insn, 5); |
| 5552 | unsigned int rm = bits (insn, 0, 3); |
| 5553 | |
| 5554 | if (debug_displaced) |
| 5555 | fprintf_unfiltered (gdb_stdlog, "displaced: copying %s register insn " |
| 5556 | "%.8lx\n", (link) ? "blx" : "bx", |
| 5557 | (unsigned long) insn); |
| 5558 | |
| 5559 | /* Implement {BX,BLX}<cond> <reg>" as: |
| 5560 | |
| 5561 | Preparation: cond <- instruction condition |
| 5562 | Insn: mov r0, r0 (nop) |
| 5563 | Cleanup: if (condition true) { r14 <- pc; pc <- dest; }. |
| 5564 | |
| 5565 | Don't set r14 in cleanup for BX. */ |
| 5566 | |
| 5567 | dsc->u.branch.dest = displaced_read_reg (regs, dsc, rm); |
| 5568 | |
| 5569 | dsc->u.branch.cond = cond; |
| 5570 | dsc->u.branch.link = link; |
| 5571 | dsc->u.branch.exchange = 1; |
| 5572 | |
| 5573 | dsc->modinsn[0] = ARM_NOP; |
| 5574 | |
| 5575 | dsc->cleanup = &cleanup_branch; |
| 5576 | |
| 5577 | return 0; |
| 5578 | } |
| 5579 | |
| 5580 | /* Copy/cleanup arithmetic/logic instruction with immediate RHS. */ |
| 5581 | |
| 5582 | static void |
| 5583 | cleanup_alu_imm (struct gdbarch *gdbarch, |
| 5584 | struct regcache *regs, struct displaced_step_closure *dsc) |
| 5585 | { |
| 5586 | ULONGEST rd_val = displaced_read_reg (regs, dsc, 0); |
| 5587 | displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC); |
| 5588 | displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC); |
| 5589 | displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC); |
| 5590 | } |
| 5591 | |
| 5592 | static int |
| 5593 | copy_alu_imm (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs, |
| 5594 | struct displaced_step_closure *dsc) |
| 5595 | { |
| 5596 | unsigned int rn = bits (insn, 16, 19); |
| 5597 | unsigned int rd = bits (insn, 12, 15); |
| 5598 | unsigned int op = bits (insn, 21, 24); |
| 5599 | int is_mov = (op == 0xd); |
| 5600 | ULONGEST rd_val, rn_val; |
| 5601 | |
| 5602 | if (!insn_references_pc (insn, 0x000ff000ul)) |
| 5603 | return copy_unmodified (gdbarch, insn, "ALU immediate", dsc); |
| 5604 | |
| 5605 | if (debug_displaced) |
| 5606 | fprintf_unfiltered (gdb_stdlog, "displaced: copying immediate %s insn " |
| 5607 | "%.8lx\n", is_mov ? "move" : "ALU", |
| 5608 | (unsigned long) insn); |
| 5609 | |
| 5610 | /* Instruction is of form: |
| 5611 | |
| 5612 | <op><cond> rd, [rn,] #imm |
| 5613 | |
| 5614 | Rewrite as: |
| 5615 | |
| 5616 | Preparation: tmp1, tmp2 <- r0, r1; |
| 5617 | r0, r1 <- rd, rn |
| 5618 | Insn: <op><cond> r0, r1, #imm |
| 5619 | Cleanup: rd <- r0; r0 <- tmp1; r1 <- tmp2 |
| 5620 | */ |
| 5621 | |
| 5622 | dsc->tmp[0] = displaced_read_reg (regs, dsc, 0); |
| 5623 | dsc->tmp[1] = displaced_read_reg (regs, dsc, 1); |
| 5624 | rn_val = displaced_read_reg (regs, dsc, rn); |
| 5625 | rd_val = displaced_read_reg (regs, dsc, rd); |
| 5626 | displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC); |
| 5627 | displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC); |
| 5628 | dsc->rd = rd; |
| 5629 | |
| 5630 | if (is_mov) |
| 5631 | dsc->modinsn[0] = insn & 0xfff00fff; |
| 5632 | else |
| 5633 | dsc->modinsn[0] = (insn & 0xfff00fff) | 0x10000; |
| 5634 | |
| 5635 | dsc->cleanup = &cleanup_alu_imm; |
| 5636 | |
| 5637 | return 0; |
| 5638 | } |
| 5639 | |
| 5640 | /* Copy/cleanup arithmetic/logic insns with register RHS. */ |
| 5641 | |
| 5642 | static void |
| 5643 | cleanup_alu_reg (struct gdbarch *gdbarch, |
| 5644 | struct regcache *regs, struct displaced_step_closure *dsc) |
| 5645 | { |
| 5646 | ULONGEST rd_val; |
| 5647 | int i; |
| 5648 | |
| 5649 | rd_val = displaced_read_reg (regs, dsc, 0); |
| 5650 | |
| 5651 | for (i = 0; i < 3; i++) |
| 5652 | displaced_write_reg (regs, dsc, i, dsc->tmp[i], CANNOT_WRITE_PC); |
| 5653 | |
| 5654 | displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC); |
| 5655 | } |
| 5656 | |
| 5657 | static int |
| 5658 | copy_alu_reg (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs, |
| 5659 | struct displaced_step_closure *dsc) |
| 5660 | { |
| 5661 | unsigned int rn = bits (insn, 16, 19); |
| 5662 | unsigned int rm = bits (insn, 0, 3); |
| 5663 | unsigned int rd = bits (insn, 12, 15); |
| 5664 | unsigned int op = bits (insn, 21, 24); |
| 5665 | int is_mov = (op == 0xd); |
| 5666 | ULONGEST rd_val, rn_val, rm_val; |
| 5667 | |
| 5668 | if (!insn_references_pc (insn, 0x000ff00ful)) |
| 5669 | return copy_unmodified (gdbarch, insn, "ALU reg", dsc); |
| 5670 | |
| 5671 | if (debug_displaced) |
| 5672 | fprintf_unfiltered (gdb_stdlog, "displaced: copying reg %s insn %.8lx\n", |
| 5673 | is_mov ? "move" : "ALU", (unsigned long) insn); |
| 5674 | |
| 5675 | /* Instruction is of form: |
| 5676 | |
| 5677 | <op><cond> rd, [rn,] rm [, <shift>] |
| 5678 | |
| 5679 | Rewrite as: |
| 5680 | |
| 5681 | Preparation: tmp1, tmp2, tmp3 <- r0, r1, r2; |
| 5682 | r0, r1, r2 <- rd, rn, rm |
| 5683 | Insn: <op><cond> r0, r1, r2 [, <shift>] |
| 5684 | Cleanup: rd <- r0; r0, r1, r2 <- tmp1, tmp2, tmp3 |
| 5685 | */ |
| 5686 | |
| 5687 | dsc->tmp[0] = displaced_read_reg (regs, dsc, 0); |
| 5688 | dsc->tmp[1] = displaced_read_reg (regs, dsc, 1); |
| 5689 | dsc->tmp[2] = displaced_read_reg (regs, dsc, 2); |
| 5690 | rd_val = displaced_read_reg (regs, dsc, rd); |
| 5691 | rn_val = displaced_read_reg (regs, dsc, rn); |
| 5692 | rm_val = displaced_read_reg (regs, dsc, rm); |
| 5693 | displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC); |
| 5694 | displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC); |
| 5695 | displaced_write_reg (regs, dsc, 2, rm_val, CANNOT_WRITE_PC); |
| 5696 | dsc->rd = rd; |
| 5697 | |
| 5698 | if (is_mov) |
| 5699 | dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x2; |
| 5700 | else |
| 5701 | dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x10002; |
| 5702 | |
| 5703 | dsc->cleanup = &cleanup_alu_reg; |
| 5704 | |
| 5705 | return 0; |
| 5706 | } |
| 5707 | |
| 5708 | /* Cleanup/copy arithmetic/logic insns with shifted register RHS. */ |
| 5709 | |
| 5710 | static void |
| 5711 | cleanup_alu_shifted_reg (struct gdbarch *gdbarch, |
| 5712 | struct regcache *regs, |
| 5713 | struct displaced_step_closure *dsc) |
| 5714 | { |
| 5715 | ULONGEST rd_val = displaced_read_reg (regs, dsc, 0); |
| 5716 | int i; |
| 5717 | |
| 5718 | for (i = 0; i < 4; i++) |
| 5719 | displaced_write_reg (regs, dsc, i, dsc->tmp[i], CANNOT_WRITE_PC); |
| 5720 | |
| 5721 | displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC); |
| 5722 | } |
| 5723 | |
| 5724 | static int |
| 5725 | copy_alu_shifted_reg (struct gdbarch *gdbarch, uint32_t insn, |
| 5726 | struct regcache *regs, |
| 5727 | struct displaced_step_closure *dsc) |
| 5728 | { |
| 5729 | unsigned int rn = bits (insn, 16, 19); |
| 5730 | unsigned int rm = bits (insn, 0, 3); |
| 5731 | unsigned int rd = bits (insn, 12, 15); |
| 5732 | unsigned int rs = bits (insn, 8, 11); |
| 5733 | unsigned int op = bits (insn, 21, 24); |
| 5734 | int is_mov = (op == 0xd), i; |
| 5735 | ULONGEST rd_val, rn_val, rm_val, rs_val; |
| 5736 | |
| 5737 | if (!insn_references_pc (insn, 0x000fff0ful)) |
| 5738 | return copy_unmodified (gdbarch, insn, "ALU shifted reg", dsc); |
| 5739 | |
| 5740 | if (debug_displaced) |
| 5741 | fprintf_unfiltered (gdb_stdlog, "displaced: copying shifted reg %s insn " |
| 5742 | "%.8lx\n", is_mov ? "move" : "ALU", |
| 5743 | (unsigned long) insn); |
| 5744 | |
| 5745 | /* Instruction is of form: |
| 5746 | |
| 5747 | <op><cond> rd, [rn,] rm, <shift> rs |
| 5748 | |
| 5749 | Rewrite as: |
| 5750 | |
| 5751 | Preparation: tmp1, tmp2, tmp3, tmp4 <- r0, r1, r2, r3 |
| 5752 | r0, r1, r2, r3 <- rd, rn, rm, rs |
| 5753 | Insn: <op><cond> r0, r1, r2, <shift> r3 |
| 5754 | Cleanup: tmp5 <- r0 |
| 5755 | r0, r1, r2, r3 <- tmp1, tmp2, tmp3, tmp4 |
| 5756 | rd <- tmp5 |
| 5757 | */ |
| 5758 | |
| 5759 | for (i = 0; i < 4; i++) |
| 5760 | dsc->tmp[i] = displaced_read_reg (regs, dsc, i); |
| 5761 | |
| 5762 | rd_val = displaced_read_reg (regs, dsc, rd); |
| 5763 | rn_val = displaced_read_reg (regs, dsc, rn); |
| 5764 | rm_val = displaced_read_reg (regs, dsc, rm); |
| 5765 | rs_val = displaced_read_reg (regs, dsc, rs); |
| 5766 | displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC); |
| 5767 | displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC); |
| 5768 | displaced_write_reg (regs, dsc, 2, rm_val, CANNOT_WRITE_PC); |
| 5769 | displaced_write_reg (regs, dsc, 3, rs_val, CANNOT_WRITE_PC); |
| 5770 | dsc->rd = rd; |
| 5771 | |
| 5772 | if (is_mov) |
| 5773 | dsc->modinsn[0] = (insn & 0xfff000f0) | 0x302; |
| 5774 | else |
| 5775 | dsc->modinsn[0] = (insn & 0xfff000f0) | 0x10302; |
| 5776 | |
| 5777 | dsc->cleanup = &cleanup_alu_shifted_reg; |
| 5778 | |
| 5779 | return 0; |
| 5780 | } |
| 5781 | |
| 5782 | /* Clean up load instructions. */ |
| 5783 | |
| 5784 | static void |
| 5785 | cleanup_load (struct gdbarch *gdbarch, struct regcache *regs, |
| 5786 | struct displaced_step_closure *dsc) |
| 5787 | { |
| 5788 | ULONGEST rt_val, rt_val2 = 0, rn_val; |
| 5789 | |
| 5790 | rt_val = displaced_read_reg (regs, dsc, 0); |
| 5791 | if (dsc->u.ldst.xfersize == 8) |
| 5792 | rt_val2 = displaced_read_reg (regs, dsc, 1); |
| 5793 | rn_val = displaced_read_reg (regs, dsc, 2); |
| 5794 | |
| 5795 | displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC); |
| 5796 | if (dsc->u.ldst.xfersize > 4) |
| 5797 | displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC); |
| 5798 | displaced_write_reg (regs, dsc, 2, dsc->tmp[2], CANNOT_WRITE_PC); |
| 5799 | if (!dsc->u.ldst.immed) |
| 5800 | displaced_write_reg (regs, dsc, 3, dsc->tmp[3], CANNOT_WRITE_PC); |
| 5801 | |
| 5802 | /* Handle register writeback. */ |
| 5803 | if (dsc->u.ldst.writeback) |
| 5804 | displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, CANNOT_WRITE_PC); |
| 5805 | /* Put result in right place. */ |
| 5806 | displaced_write_reg (regs, dsc, dsc->rd, rt_val, LOAD_WRITE_PC); |
| 5807 | if (dsc->u.ldst.xfersize == 8) |
| 5808 | displaced_write_reg (regs, dsc, dsc->rd + 1, rt_val2, LOAD_WRITE_PC); |
| 5809 | } |
| 5810 | |
| 5811 | /* Clean up store instructions. */ |
| 5812 | |
| 5813 | static void |
| 5814 | cleanup_store (struct gdbarch *gdbarch, struct regcache *regs, |
| 5815 | struct displaced_step_closure *dsc) |
| 5816 | { |
| 5817 | ULONGEST rn_val = displaced_read_reg (regs, dsc, 2); |
| 5818 | |
| 5819 | displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC); |
| 5820 | if (dsc->u.ldst.xfersize > 4) |
| 5821 | displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC); |
| 5822 | displaced_write_reg (regs, dsc, 2, dsc->tmp[2], CANNOT_WRITE_PC); |
| 5823 | if (!dsc->u.ldst.immed) |
| 5824 | displaced_write_reg (regs, dsc, 3, dsc->tmp[3], CANNOT_WRITE_PC); |
| 5825 | if (!dsc->u.ldst.restore_r4) |
| 5826 | displaced_write_reg (regs, dsc, 4, dsc->tmp[4], CANNOT_WRITE_PC); |
| 5827 | |
| 5828 | /* Writeback. */ |
| 5829 | if (dsc->u.ldst.writeback) |
| 5830 | displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, CANNOT_WRITE_PC); |
| 5831 | } |
| 5832 | |
| 5833 | /* Copy "extra" load/store instructions. These are halfword/doubleword |
| 5834 | transfers, which have a different encoding to byte/word transfers. */ |
| 5835 | |
| 5836 | static int |
| 5837 | copy_extra_ld_st (struct gdbarch *gdbarch, uint32_t insn, int unpriveleged, |
| 5838 | struct regcache *regs, struct displaced_step_closure *dsc) |
| 5839 | { |
| 5840 | unsigned int op1 = bits (insn, 20, 24); |
| 5841 | unsigned int op2 = bits (insn, 5, 6); |
| 5842 | unsigned int rt = bits (insn, 12, 15); |
| 5843 | unsigned int rn = bits (insn, 16, 19); |
| 5844 | unsigned int rm = bits (insn, 0, 3); |
| 5845 | char load[12] = {0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1}; |
| 5846 | char bytesize[12] = {2, 2, 2, 2, 8, 1, 8, 1, 8, 2, 8, 2}; |
| 5847 | int immed = (op1 & 0x4) != 0; |
| 5848 | int opcode; |
| 5849 | ULONGEST rt_val, rt_val2 = 0, rn_val, rm_val = 0; |
| 5850 | |
| 5851 | if (!insn_references_pc (insn, 0x000ff00ful)) |
| 5852 | return copy_unmodified (gdbarch, insn, "extra load/store", dsc); |
| 5853 | |
| 5854 | if (debug_displaced) |
| 5855 | fprintf_unfiltered (gdb_stdlog, "displaced: copying %sextra load/store " |
| 5856 | "insn %.8lx\n", unpriveleged ? "unpriveleged " : "", |
| 5857 | (unsigned long) insn); |
| 5858 | |
| 5859 | opcode = ((op2 << 2) | (op1 & 0x1) | ((op1 & 0x4) >> 1)) - 4; |
| 5860 | |
| 5861 | if (opcode < 0) |
| 5862 | internal_error (__FILE__, __LINE__, |
| 5863 | _("copy_extra_ld_st: instruction decode error")); |
| 5864 | |
| 5865 | dsc->tmp[0] = displaced_read_reg (regs, dsc, 0); |
| 5866 | dsc->tmp[1] = displaced_read_reg (regs, dsc, 1); |
| 5867 | dsc->tmp[2] = displaced_read_reg (regs, dsc, 2); |
| 5868 | if (!immed) |
| 5869 | dsc->tmp[3] = displaced_read_reg (regs, dsc, 3); |
| 5870 | |
| 5871 | rt_val = displaced_read_reg (regs, dsc, rt); |
| 5872 | if (bytesize[opcode] == 8) |
| 5873 | rt_val2 = displaced_read_reg (regs, dsc, rt + 1); |
| 5874 | rn_val = displaced_read_reg (regs, dsc, rn); |
| 5875 | if (!immed) |
| 5876 | rm_val = displaced_read_reg (regs, dsc, rm); |
| 5877 | |
| 5878 | displaced_write_reg (regs, dsc, 0, rt_val, CANNOT_WRITE_PC); |
| 5879 | if (bytesize[opcode] == 8) |
| 5880 | displaced_write_reg (regs, dsc, 1, rt_val2, CANNOT_WRITE_PC); |
| 5881 | displaced_write_reg (regs, dsc, 2, rn_val, CANNOT_WRITE_PC); |
| 5882 | if (!immed) |
| 5883 | displaced_write_reg (regs, dsc, 3, rm_val, CANNOT_WRITE_PC); |
| 5884 | |
| 5885 | dsc->rd = rt; |
| 5886 | dsc->u.ldst.xfersize = bytesize[opcode]; |
| 5887 | dsc->u.ldst.rn = rn; |
| 5888 | dsc->u.ldst.immed = immed; |
| 5889 | dsc->u.ldst.writeback = bit (insn, 24) == 0 || bit (insn, 21) != 0; |
| 5890 | dsc->u.ldst.restore_r4 = 0; |
| 5891 | |
| 5892 | if (immed) |
| 5893 | /* {ldr,str}<width><cond> rt, [rt2,] [rn, #imm] |
| 5894 | -> |
| 5895 | {ldr,str}<width><cond> r0, [r1,] [r2, #imm]. */ |
| 5896 | dsc->modinsn[0] = (insn & 0xfff00fff) | 0x20000; |
| 5897 | else |
| 5898 | /* {ldr,str}<width><cond> rt, [rt2,] [rn, +/-rm] |
| 5899 | -> |
| 5900 | {ldr,str}<width><cond> r0, [r1,] [r2, +/-r3]. */ |
| 5901 | dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x20003; |
| 5902 | |
| 5903 | dsc->cleanup = load[opcode] ? &cleanup_load : &cleanup_store; |
| 5904 | |
| 5905 | return 0; |
| 5906 | } |
| 5907 | |
| 5908 | /* Copy byte/word loads and stores. */ |
| 5909 | |
| 5910 | static int |
| 5911 | copy_ldr_str_ldrb_strb (struct gdbarch *gdbarch, uint32_t insn, |
| 5912 | struct regcache *regs, |
| 5913 | struct displaced_step_closure *dsc, int load, int byte, |
| 5914 | int usermode) |
| 5915 | { |
| 5916 | int immed = !bit (insn, 25); |
| 5917 | unsigned int rt = bits (insn, 12, 15); |
| 5918 | unsigned int rn = bits (insn, 16, 19); |
| 5919 | unsigned int rm = bits (insn, 0, 3); /* Only valid if !immed. */ |
| 5920 | ULONGEST rt_val, rn_val, rm_val = 0; |
| 5921 | |
| 5922 | if (!insn_references_pc (insn, 0x000ff00ful)) |
| 5923 | return copy_unmodified (gdbarch, insn, "load/store", dsc); |
| 5924 | |
| 5925 | if (debug_displaced) |
| 5926 | fprintf_unfiltered (gdb_stdlog, "displaced: copying %s%s insn %.8lx\n", |
| 5927 | load ? (byte ? "ldrb" : "ldr") |
| 5928 | : (byte ? "strb" : "str"), usermode ? "t" : "", |
| 5929 | (unsigned long) insn); |
| 5930 | |
| 5931 | dsc->tmp[0] = displaced_read_reg (regs, dsc, 0); |
| 5932 | dsc->tmp[2] = displaced_read_reg (regs, dsc, 2); |
| 5933 | if (!immed) |
| 5934 | dsc->tmp[3] = displaced_read_reg (regs, dsc, 3); |
| 5935 | if (!load) |
| 5936 | dsc->tmp[4] = displaced_read_reg (regs, dsc, 4); |
| 5937 | |
| 5938 | rt_val = displaced_read_reg (regs, dsc, rt); |
| 5939 | rn_val = displaced_read_reg (regs, dsc, rn); |
| 5940 | if (!immed) |
| 5941 | rm_val = displaced_read_reg (regs, dsc, rm); |
| 5942 | |
| 5943 | displaced_write_reg (regs, dsc, 0, rt_val, CANNOT_WRITE_PC); |
| 5944 | displaced_write_reg (regs, dsc, 2, rn_val, CANNOT_WRITE_PC); |
| 5945 | if (!immed) |
| 5946 | displaced_write_reg (regs, dsc, 3, rm_val, CANNOT_WRITE_PC); |
| 5947 | |
| 5948 | dsc->rd = rt; |
| 5949 | dsc->u.ldst.xfersize = byte ? 1 : 4; |
| 5950 | dsc->u.ldst.rn = rn; |
| 5951 | dsc->u.ldst.immed = immed; |
| 5952 | dsc->u.ldst.writeback = bit (insn, 24) == 0 || bit (insn, 21) != 0; |
| 5953 | |
| 5954 | /* To write PC we can do: |
| 5955 | |
| 5956 | Before this sequence of instructions: |
| 5957 | r0 is the PC value got from displaced_read_reg, so r0 = from + 8; |
| 5958 | r2 is the Rn value got from dispalced_read_reg. |
| 5959 | |
| 5960 | Insn1: push {pc} Write address of STR instruction + offset on stack |
| 5961 | Insn2: pop {r4} Read it back from stack, r4 = addr(Insn1) + offset |
| 5962 | Insn3: sub r4, r4, pc r4 = addr(Insn1) + offset - pc |
| 5963 | = addr(Insn1) + offset - addr(Insn3) - 8 |
| 5964 | = offset - 16 |
| 5965 | Insn4: add r4, r4, #8 r4 = offset - 8 |
| 5966 | Insn5: add r0, r0, r4 r0 = from + 8 + offset - 8 |
| 5967 | = from + offset |
| 5968 | Insn6: str r0, [r2, #imm] (or str r0, [r2, r3]) |
| 5969 | |
| 5970 | Otherwise we don't know what value to write for PC, since the offset is |
| 5971 | architecture-dependent (sometimes PC+8, sometimes PC+12). More details |
| 5972 | of this can be found in Section "Saving from r15" in |
| 5973 | http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0204g/Cihbjifh.html */ |
| 5974 | |
| 5975 | if (load || rt != ARM_PC_REGNUM) |
| 5976 | { |
| 5977 | dsc->u.ldst.restore_r4 = 0; |
| 5978 | |
| 5979 | if (immed) |
| 5980 | /* {ldr,str}[b]<cond> rt, [rn, #imm], etc. |
| 5981 | -> |
| 5982 | {ldr,str}[b]<cond> r0, [r2, #imm]. */ |
| 5983 | dsc->modinsn[0] = (insn & 0xfff00fff) | 0x20000; |
| 5984 | else |
| 5985 | /* {ldr,str}[b]<cond> rt, [rn, rm], etc. |
| 5986 | -> |
| 5987 | {ldr,str}[b]<cond> r0, [r2, r3]. */ |
| 5988 | dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x20003; |
| 5989 | } |
| 5990 | else |
| 5991 | { |
| 5992 | /* We need to use r4 as scratch. Make sure it's restored afterwards. */ |
| 5993 | dsc->u.ldst.restore_r4 = 1; |
| 5994 | dsc->modinsn[0] = 0xe92d8000; /* push {pc} */ |
| 5995 | dsc->modinsn[1] = 0xe8bd0010; /* pop {r4} */ |
| 5996 | dsc->modinsn[2] = 0xe044400f; /* sub r4, r4, pc. */ |
| 5997 | dsc->modinsn[3] = 0xe2844008; /* add r4, r4, #8. */ |
| 5998 | dsc->modinsn[4] = 0xe0800004; /* add r0, r0, r4. */ |
| 5999 | |
| 6000 | /* As above. */ |
| 6001 | if (immed) |
| 6002 | dsc->modinsn[5] = (insn & 0xfff00fff) | 0x20000; |
| 6003 | else |
| 6004 | dsc->modinsn[5] = (insn & 0xfff00ff0) | 0x20003; |
| 6005 | |
| 6006 | dsc->numinsns = 6; |
| 6007 | } |
| 6008 | |
| 6009 | dsc->cleanup = load ? &cleanup_load : &cleanup_store; |
| 6010 | |
| 6011 | return 0; |
| 6012 | } |
| 6013 | |
| 6014 | /* Cleanup LDM instructions with fully-populated register list. This is an |
| 6015 | unfortunate corner case: it's impossible to implement correctly by modifying |
| 6016 | the instruction. The issue is as follows: we have an instruction, |
| 6017 | |
| 6018 | ldm rN, {r0-r15} |
| 6019 | |
| 6020 | which we must rewrite to avoid loading PC. A possible solution would be to |
| 6021 | do the load in two halves, something like (with suitable cleanup |
| 6022 | afterwards): |
| 6023 | |
| 6024 | mov r8, rN |
| 6025 | ldm[id][ab] r8!, {r0-r7} |
| 6026 | str r7, <temp> |
| 6027 | ldm[id][ab] r8, {r7-r14} |
| 6028 | <bkpt> |
| 6029 | |
| 6030 | but at present there's no suitable place for <temp>, since the scratch space |
| 6031 | is overwritten before the cleanup routine is called. For now, we simply |
| 6032 | emulate the instruction. */ |
| 6033 | |
| 6034 | static void |
| 6035 | cleanup_block_load_all (struct gdbarch *gdbarch, struct regcache *regs, |
| 6036 | struct displaced_step_closure *dsc) |
| 6037 | { |
| 6038 | int inc = dsc->u.block.increment; |
| 6039 | int bump_before = dsc->u.block.before ? (inc ? 4 : -4) : 0; |
| 6040 | int bump_after = dsc->u.block.before ? 0 : (inc ? 4 : -4); |
| 6041 | uint32_t regmask = dsc->u.block.regmask; |
| 6042 | int regno = inc ? 0 : 15; |
| 6043 | CORE_ADDR xfer_addr = dsc->u.block.xfer_addr; |
| 6044 | int exception_return = dsc->u.block.load && dsc->u.block.user |
| 6045 | && (regmask & 0x8000) != 0; |
| 6046 | uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM); |
| 6047 | int do_transfer = condition_true (dsc->u.block.cond, status); |
| 6048 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 6049 | |
| 6050 | if (!do_transfer) |
| 6051 | return; |
| 6052 | |
| 6053 | /* If the instruction is ldm rN, {...pc}^, I don't think there's anything |
| 6054 | sensible we can do here. Complain loudly. */ |
| 6055 | if (exception_return) |
| 6056 | error (_("Cannot single-step exception return")); |
| 6057 | |
| 6058 | /* We don't handle any stores here for now. */ |
| 6059 | gdb_assert (dsc->u.block.load != 0); |
| 6060 | |
| 6061 | if (debug_displaced) |
| 6062 | fprintf_unfiltered (gdb_stdlog, "displaced: emulating block transfer: " |
| 6063 | "%s %s %s\n", dsc->u.block.load ? "ldm" : "stm", |
| 6064 | dsc->u.block.increment ? "inc" : "dec", |
| 6065 | dsc->u.block.before ? "before" : "after"); |
| 6066 | |
| 6067 | while (regmask) |
| 6068 | { |
| 6069 | uint32_t memword; |
| 6070 | |
| 6071 | if (inc) |
| 6072 | while (regno <= ARM_PC_REGNUM && (regmask & (1 << regno)) == 0) |
| 6073 | regno++; |
| 6074 | else |
| 6075 | while (regno >= 0 && (regmask & (1 << regno)) == 0) |
| 6076 | regno--; |
| 6077 | |
| 6078 | xfer_addr += bump_before; |
| 6079 | |
| 6080 | memword = read_memory_unsigned_integer (xfer_addr, 4, byte_order); |
| 6081 | displaced_write_reg (regs, dsc, regno, memword, LOAD_WRITE_PC); |
| 6082 | |
| 6083 | xfer_addr += bump_after; |
| 6084 | |
| 6085 | regmask &= ~(1 << regno); |
| 6086 | } |
| 6087 | |
| 6088 | if (dsc->u.block.writeback) |
| 6089 | displaced_write_reg (regs, dsc, dsc->u.block.rn, xfer_addr, |
| 6090 | CANNOT_WRITE_PC); |
| 6091 | } |
| 6092 | |
| 6093 | /* Clean up an STM which included the PC in the register list. */ |
| 6094 | |
| 6095 | static void |
| 6096 | cleanup_block_store_pc (struct gdbarch *gdbarch, struct regcache *regs, |
| 6097 | struct displaced_step_closure *dsc) |
| 6098 | { |
| 6099 | uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM); |
| 6100 | int store_executed = condition_true (dsc->u.block.cond, status); |
| 6101 | CORE_ADDR pc_stored_at, transferred_regs = bitcount (dsc->u.block.regmask); |
| 6102 | CORE_ADDR stm_insn_addr; |
| 6103 | uint32_t pc_val; |
| 6104 | long offset; |
| 6105 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 6106 | |
| 6107 | /* If condition code fails, there's nothing else to do. */ |
| 6108 | if (!store_executed) |
| 6109 | return; |
| 6110 | |
| 6111 | if (dsc->u.block.increment) |
| 6112 | { |
| 6113 | pc_stored_at = dsc->u.block.xfer_addr + 4 * transferred_regs; |
| 6114 | |
| 6115 | if (dsc->u.block.before) |
| 6116 | pc_stored_at += 4; |
| 6117 | } |
| 6118 | else |
| 6119 | { |
| 6120 | pc_stored_at = dsc->u.block.xfer_addr; |
| 6121 | |
| 6122 | if (dsc->u.block.before) |
| 6123 | pc_stored_at -= 4; |
| 6124 | } |
| 6125 | |
| 6126 | pc_val = read_memory_unsigned_integer (pc_stored_at, 4, byte_order); |
| 6127 | stm_insn_addr = dsc->scratch_base; |
| 6128 | offset = pc_val - stm_insn_addr; |
| 6129 | |
| 6130 | if (debug_displaced) |
| 6131 | fprintf_unfiltered (gdb_stdlog, "displaced: detected PC offset %.8lx for " |
| 6132 | "STM instruction\n", offset); |
| 6133 | |
| 6134 | /* Rewrite the stored PC to the proper value for the non-displaced original |
| 6135 | instruction. */ |
| 6136 | write_memory_unsigned_integer (pc_stored_at, 4, byte_order, |
| 6137 | dsc->insn_addr + offset); |
| 6138 | } |
| 6139 | |
| 6140 | /* Clean up an LDM which includes the PC in the register list. We clumped all |
| 6141 | the registers in the transferred list into a contiguous range r0...rX (to |
| 6142 | avoid loading PC directly and losing control of the debugged program), so we |
| 6143 | must undo that here. */ |
| 6144 | |
| 6145 | static void |
| 6146 | cleanup_block_load_pc (struct gdbarch *gdbarch, |
| 6147 | struct regcache *regs, |
| 6148 | struct displaced_step_closure *dsc) |
| 6149 | { |
| 6150 | uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM); |
| 6151 | int load_executed = condition_true (dsc->u.block.cond, status), i; |
| 6152 | unsigned int mask = dsc->u.block.regmask, write_reg = ARM_PC_REGNUM; |
| 6153 | unsigned int regs_loaded = bitcount (mask); |
| 6154 | unsigned int num_to_shuffle = regs_loaded, clobbered; |
| 6155 | |
| 6156 | /* The method employed here will fail if the register list is fully populated |
| 6157 | (we need to avoid loading PC directly). */ |
| 6158 | gdb_assert (num_to_shuffle < 16); |
| 6159 | |
| 6160 | if (!load_executed) |
| 6161 | return; |
| 6162 | |
| 6163 | clobbered = (1 << num_to_shuffle) - 1; |
| 6164 | |
| 6165 | while (num_to_shuffle > 0) |
| 6166 | { |
| 6167 | if ((mask & (1 << write_reg)) != 0) |
| 6168 | { |
| 6169 | unsigned int read_reg = num_to_shuffle - 1; |
| 6170 | |
| 6171 | if (read_reg != write_reg) |
| 6172 | { |
| 6173 | ULONGEST rval = displaced_read_reg (regs, dsc, read_reg); |
| 6174 | displaced_write_reg (regs, dsc, write_reg, rval, LOAD_WRITE_PC); |
| 6175 | if (debug_displaced) |
| 6176 | fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: move " |
| 6177 | "loaded register r%d to r%d\n"), read_reg, |
| 6178 | write_reg); |
| 6179 | } |
| 6180 | else if (debug_displaced) |
| 6181 | fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: register " |
| 6182 | "r%d already in the right place\n"), |
| 6183 | write_reg); |
| 6184 | |
| 6185 | clobbered &= ~(1 << write_reg); |
| 6186 | |
| 6187 | num_to_shuffle--; |
| 6188 | } |
| 6189 | |
| 6190 | write_reg--; |
| 6191 | } |
| 6192 | |
| 6193 | /* Restore any registers we scribbled over. */ |
| 6194 | for (write_reg = 0; clobbered != 0; write_reg++) |
| 6195 | { |
| 6196 | if ((clobbered & (1 << write_reg)) != 0) |
| 6197 | { |
| 6198 | displaced_write_reg (regs, dsc, write_reg, dsc->tmp[write_reg], |
| 6199 | CANNOT_WRITE_PC); |
| 6200 | if (debug_displaced) |
| 6201 | fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: restored " |
| 6202 | "clobbered register r%d\n"), write_reg); |
| 6203 | clobbered &= ~(1 << write_reg); |
| 6204 | } |
| 6205 | } |
| 6206 | |
| 6207 | /* Perform register writeback manually. */ |
| 6208 | if (dsc->u.block.writeback) |
| 6209 | { |
| 6210 | ULONGEST new_rn_val = dsc->u.block.xfer_addr; |
| 6211 | |
| 6212 | if (dsc->u.block.increment) |
| 6213 | new_rn_val += regs_loaded * 4; |
| 6214 | else |
| 6215 | new_rn_val -= regs_loaded * 4; |
| 6216 | |
| 6217 | displaced_write_reg (regs, dsc, dsc->u.block.rn, new_rn_val, |
| 6218 | CANNOT_WRITE_PC); |
| 6219 | } |
| 6220 | } |
| 6221 | |
| 6222 | /* Handle ldm/stm, apart from some tricky cases which are unlikely to occur |
| 6223 | in user-level code (in particular exception return, ldm rn, {...pc}^). */ |
| 6224 | |
| 6225 | static int |
| 6226 | copy_block_xfer (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs, |
| 6227 | struct displaced_step_closure *dsc) |
| 6228 | { |
| 6229 | int load = bit (insn, 20); |
| 6230 | int user = bit (insn, 22); |
| 6231 | int increment = bit (insn, 23); |
| 6232 | int before = bit (insn, 24); |
| 6233 | int writeback = bit (insn, 21); |
| 6234 | int rn = bits (insn, 16, 19); |
| 6235 | |
| 6236 | /* Block transfers which don't mention PC can be run directly |
| 6237 | out-of-line. */ |
| 6238 | if (rn != ARM_PC_REGNUM && (insn & 0x8000) == 0) |
| 6239 | return copy_unmodified (gdbarch, insn, "ldm/stm", dsc); |
| 6240 | |
| 6241 | if (rn == ARM_PC_REGNUM) |
| 6242 | { |
| 6243 | warning (_("displaced: Unpredictable LDM or STM with " |
| 6244 | "base register r15")); |
| 6245 | return copy_unmodified (gdbarch, insn, "unpredictable ldm/stm", dsc); |
| 6246 | } |
| 6247 | |
| 6248 | if (debug_displaced) |
| 6249 | fprintf_unfiltered (gdb_stdlog, "displaced: copying block transfer insn " |
| 6250 | "%.8lx\n", (unsigned long) insn); |
| 6251 | |
| 6252 | dsc->u.block.xfer_addr = displaced_read_reg (regs, dsc, rn); |
| 6253 | dsc->u.block.rn = rn; |
| 6254 | |
| 6255 | dsc->u.block.load = load; |
| 6256 | dsc->u.block.user = user; |
| 6257 | dsc->u.block.increment = increment; |
| 6258 | dsc->u.block.before = before; |
| 6259 | dsc->u.block.writeback = writeback; |
| 6260 | dsc->u.block.cond = bits (insn, 28, 31); |
| 6261 | |
| 6262 | dsc->u.block.regmask = insn & 0xffff; |
| 6263 | |
| 6264 | if (load) |
| 6265 | { |
| 6266 | if ((insn & 0xffff) == 0xffff) |
| 6267 | { |
| 6268 | /* LDM with a fully-populated register list. This case is |
| 6269 | particularly tricky. Implement for now by fully emulating the |
| 6270 | instruction (which might not behave perfectly in all cases, but |
| 6271 | these instructions should be rare enough for that not to matter |
| 6272 | too much). */ |
| 6273 | dsc->modinsn[0] = ARM_NOP; |
| 6274 | |
| 6275 | dsc->cleanup = &cleanup_block_load_all; |
| 6276 | } |
| 6277 | else |
| 6278 | { |
| 6279 | /* LDM of a list of registers which includes PC. Implement by |
| 6280 | rewriting the list of registers to be transferred into a |
| 6281 | contiguous chunk r0...rX before doing the transfer, then shuffling |
| 6282 | registers into the correct places in the cleanup routine. */ |
| 6283 | unsigned int regmask = insn & 0xffff; |
| 6284 | unsigned int num_in_list = bitcount (regmask), new_regmask, bit = 1; |
| 6285 | unsigned int to = 0, from = 0, i, new_rn; |
| 6286 | |
| 6287 | for (i = 0; i < num_in_list; i++) |
| 6288 | dsc->tmp[i] = displaced_read_reg (regs, dsc, i); |
| 6289 | |
| 6290 | /* Writeback makes things complicated. We need to avoid clobbering |
| 6291 | the base register with one of the registers in our modified |
| 6292 | register list, but just using a different register can't work in |
| 6293 | all cases, e.g.: |
| 6294 | |
| 6295 | ldm r14!, {r0-r13,pc} |
| 6296 | |
| 6297 | which would need to be rewritten as: |
| 6298 | |
| 6299 | ldm rN!, {r0-r14} |
| 6300 | |
| 6301 | but that can't work, because there's no free register for N. |
| 6302 | |
| 6303 | Solve this by turning off the writeback bit, and emulating |
| 6304 | writeback manually in the cleanup routine. */ |
| 6305 | |
| 6306 | if (writeback) |
| 6307 | insn &= ~(1 << 21); |
| 6308 | |
| 6309 | new_regmask = (1 << num_in_list) - 1; |
| 6310 | |
| 6311 | if (debug_displaced) |
| 6312 | fprintf_unfiltered (gdb_stdlog, _("displaced: LDM r%d%s, " |
| 6313 | "{..., pc}: original reg list %.4x, modified " |
| 6314 | "list %.4x\n"), rn, writeback ? "!" : "", |
| 6315 | (int) insn & 0xffff, new_regmask); |
| 6316 | |
| 6317 | dsc->modinsn[0] = (insn & ~0xffff) | (new_regmask & 0xffff); |
| 6318 | |
| 6319 | dsc->cleanup = &cleanup_block_load_pc; |
| 6320 | } |
| 6321 | } |
| 6322 | else |
| 6323 | { |
| 6324 | /* STM of a list of registers which includes PC. Run the instruction |
| 6325 | as-is, but out of line: this will store the wrong value for the PC, |
| 6326 | so we must manually fix up the memory in the cleanup routine. |
| 6327 | Doing things this way has the advantage that we can auto-detect |
| 6328 | the offset of the PC write (which is architecture-dependent) in |
| 6329 | the cleanup routine. */ |
| 6330 | dsc->modinsn[0] = insn; |
| 6331 | |
| 6332 | dsc->cleanup = &cleanup_block_store_pc; |
| 6333 | } |
| 6334 | |
| 6335 | return 0; |
| 6336 | } |
| 6337 | |
| 6338 | /* Cleanup/copy SVC (SWI) instructions. These two functions are overridden |
| 6339 | for Linux, where some SVC instructions must be treated specially. */ |
| 6340 | |
| 6341 | static void |
| 6342 | cleanup_svc (struct gdbarch *gdbarch, struct regcache *regs, |
| 6343 | struct displaced_step_closure *dsc) |
| 6344 | { |
| 6345 | CORE_ADDR resume_addr = dsc->insn_addr + 4; |
| 6346 | |
| 6347 | if (debug_displaced) |
| 6348 | fprintf_unfiltered (gdb_stdlog, "displaced: cleanup for svc, resume at " |
| 6349 | "%.8lx\n", (unsigned long) resume_addr); |
| 6350 | |
| 6351 | displaced_write_reg (regs, dsc, ARM_PC_REGNUM, resume_addr, BRANCH_WRITE_PC); |
| 6352 | } |
| 6353 | |
| 6354 | static int |
| 6355 | copy_svc (struct gdbarch *gdbarch, uint32_t insn, CORE_ADDR to, |
| 6356 | struct regcache *regs, struct displaced_step_closure *dsc) |
| 6357 | { |
| 6358 | /* Allow OS-specific code to override SVC handling. */ |
| 6359 | if (dsc->u.svc.copy_svc_os) |
| 6360 | return dsc->u.svc.copy_svc_os (gdbarch, insn, to, regs, dsc); |
| 6361 | |
| 6362 | if (debug_displaced) |
| 6363 | fprintf_unfiltered (gdb_stdlog, "displaced: copying svc insn %.8lx\n", |
| 6364 | (unsigned long) insn); |
| 6365 | |
| 6366 | /* Preparation: none. |
| 6367 | Insn: unmodified svc. |
| 6368 | Cleanup: pc <- insn_addr + 4. */ |
| 6369 | |
| 6370 | dsc->modinsn[0] = insn; |
| 6371 | |
| 6372 | dsc->cleanup = &cleanup_svc; |
| 6373 | /* Pretend we wrote to the PC, so cleanup doesn't set PC to the next |
| 6374 | instruction. */ |
| 6375 | dsc->wrote_to_pc = 1; |
| 6376 | |
| 6377 | return 0; |
| 6378 | } |
| 6379 | |
| 6380 | /* Copy undefined instructions. */ |
| 6381 | |
| 6382 | static int |
| 6383 | copy_undef (struct gdbarch *gdbarch, uint32_t insn, |
| 6384 | struct displaced_step_closure *dsc) |
| 6385 | { |
| 6386 | if (debug_displaced) |
| 6387 | fprintf_unfiltered (gdb_stdlog, |
| 6388 | "displaced: copying undefined insn %.8lx\n", |
| 6389 | (unsigned long) insn); |
| 6390 | |
| 6391 | dsc->modinsn[0] = insn; |
| 6392 | |
| 6393 | return 0; |
| 6394 | } |
| 6395 | |
| 6396 | /* Copy unpredictable instructions. */ |
| 6397 | |
| 6398 | static int |
| 6399 | copy_unpred (struct gdbarch *gdbarch, uint32_t insn, |
| 6400 | struct displaced_step_closure *dsc) |
| 6401 | { |
| 6402 | if (debug_displaced) |
| 6403 | fprintf_unfiltered (gdb_stdlog, "displaced: copying unpredictable insn " |
| 6404 | "%.8lx\n", (unsigned long) insn); |
| 6405 | |
| 6406 | dsc->modinsn[0] = insn; |
| 6407 | |
| 6408 | return 0; |
| 6409 | } |
| 6410 | |
| 6411 | /* The decode_* functions are instruction decoding helpers. They mostly follow |
| 6412 | the presentation in the ARM ARM. */ |
| 6413 | |
| 6414 | static int |
| 6415 | decode_misc_memhint_neon (struct gdbarch *gdbarch, uint32_t insn, |
| 6416 | struct regcache *regs, |
| 6417 | struct displaced_step_closure *dsc) |
| 6418 | { |
| 6419 | unsigned int op1 = bits (insn, 20, 26), op2 = bits (insn, 4, 7); |
| 6420 | unsigned int rn = bits (insn, 16, 19); |
| 6421 | |
| 6422 | if (op1 == 0x10 && (op2 & 0x2) == 0x0 && (rn & 0xe) == 0x0) |
| 6423 | return copy_unmodified (gdbarch, insn, "cps", dsc); |
| 6424 | else if (op1 == 0x10 && op2 == 0x0 && (rn & 0xe) == 0x1) |
| 6425 | return copy_unmodified (gdbarch, insn, "setend", dsc); |
| 6426 | else if ((op1 & 0x60) == 0x20) |
| 6427 | return copy_unmodified (gdbarch, insn, "neon dataproc", dsc); |
| 6428 | else if ((op1 & 0x71) == 0x40) |
| 6429 | return copy_unmodified (gdbarch, insn, "neon elt/struct load/store", dsc); |
| 6430 | else if ((op1 & 0x77) == 0x41) |
| 6431 | return copy_unmodified (gdbarch, insn, "unallocated mem hint", dsc); |
| 6432 | else if ((op1 & 0x77) == 0x45) |
| 6433 | return copy_preload (gdbarch, insn, regs, dsc); /* pli. */ |
| 6434 | else if ((op1 & 0x77) == 0x51) |
| 6435 | { |
| 6436 | if (rn != 0xf) |
| 6437 | return copy_preload (gdbarch, insn, regs, dsc); /* pld/pldw. */ |
| 6438 | else |
| 6439 | return copy_unpred (gdbarch, insn, dsc); |
| 6440 | } |
| 6441 | else if ((op1 & 0x77) == 0x55) |
| 6442 | return copy_preload (gdbarch, insn, regs, dsc); /* pld/pldw. */ |
| 6443 | else if (op1 == 0x57) |
| 6444 | switch (op2) |
| 6445 | { |
| 6446 | case 0x1: return copy_unmodified (gdbarch, insn, "clrex", dsc); |
| 6447 | case 0x4: return copy_unmodified (gdbarch, insn, "dsb", dsc); |
| 6448 | case 0x5: return copy_unmodified (gdbarch, insn, "dmb", dsc); |
| 6449 | case 0x6: return copy_unmodified (gdbarch, insn, "isb", dsc); |
| 6450 | default: return copy_unpred (gdbarch, insn, dsc); |
| 6451 | } |
| 6452 | else if ((op1 & 0x63) == 0x43) |
| 6453 | return copy_unpred (gdbarch, insn, dsc); |
| 6454 | else if ((op2 & 0x1) == 0x0) |
| 6455 | switch (op1 & ~0x80) |
| 6456 | { |
| 6457 | case 0x61: |
| 6458 | return copy_unmodified (gdbarch, insn, "unallocated mem hint", dsc); |
| 6459 | case 0x65: |
| 6460 | return copy_preload_reg (gdbarch, insn, regs, dsc); /* pli reg. */ |
| 6461 | case 0x71: case 0x75: |
| 6462 | /* pld/pldw reg. */ |
| 6463 | return copy_preload_reg (gdbarch, insn, regs, dsc); |
| 6464 | case 0x63: case 0x67: case 0x73: case 0x77: |
| 6465 | return copy_unpred (gdbarch, insn, dsc); |
| 6466 | default: |
| 6467 | return copy_undef (gdbarch, insn, dsc); |
| 6468 | } |
| 6469 | else |
| 6470 | return copy_undef (gdbarch, insn, dsc); /* Probably unreachable. */ |
| 6471 | } |
| 6472 | |
| 6473 | static int |
| 6474 | decode_unconditional (struct gdbarch *gdbarch, uint32_t insn, |
| 6475 | struct regcache *regs, |
| 6476 | struct displaced_step_closure *dsc) |
| 6477 | { |
| 6478 | if (bit (insn, 27) == 0) |
| 6479 | return decode_misc_memhint_neon (gdbarch, insn, regs, dsc); |
| 6480 | /* Switch on bits: 0bxxxxx321xxx0xxxxxxxxxxxxxxxxxxxx. */ |
| 6481 | else switch (((insn & 0x7000000) >> 23) | ((insn & 0x100000) >> 20)) |
| 6482 | { |
| 6483 | case 0x0: case 0x2: |
| 6484 | return copy_unmodified (gdbarch, insn, "srs", dsc); |
| 6485 | |
| 6486 | case 0x1: case 0x3: |
| 6487 | return copy_unmodified (gdbarch, insn, "rfe", dsc); |
| 6488 | |
| 6489 | case 0x4: case 0x5: case 0x6: case 0x7: |
| 6490 | return copy_b_bl_blx (gdbarch, insn, regs, dsc); |
| 6491 | |
| 6492 | case 0x8: |
| 6493 | switch ((insn & 0xe00000) >> 21) |
| 6494 | { |
| 6495 | case 0x1: case 0x3: case 0x4: case 0x5: case 0x6: case 0x7: |
| 6496 | /* stc/stc2. */ |
| 6497 | return copy_copro_load_store (gdbarch, insn, regs, dsc); |
| 6498 | |
| 6499 | case 0x2: |
| 6500 | return copy_unmodified (gdbarch, insn, "mcrr/mcrr2", dsc); |
| 6501 | |
| 6502 | default: |
| 6503 | return copy_undef (gdbarch, insn, dsc); |
| 6504 | } |
| 6505 | |
| 6506 | case 0x9: |
| 6507 | { |
| 6508 | int rn_f = (bits (insn, 16, 19) == 0xf); |
| 6509 | switch ((insn & 0xe00000) >> 21) |
| 6510 | { |
| 6511 | case 0x1: case 0x3: |
| 6512 | /* ldc/ldc2 imm (undefined for rn == pc). */ |
| 6513 | return rn_f ? copy_undef (gdbarch, insn, dsc) |
| 6514 | : copy_copro_load_store (gdbarch, insn, regs, dsc); |
| 6515 | |
| 6516 | case 0x2: |
| 6517 | return copy_unmodified (gdbarch, insn, "mrrc/mrrc2", dsc); |
| 6518 | |
| 6519 | case 0x4: case 0x5: case 0x6: case 0x7: |
| 6520 | /* ldc/ldc2 lit (undefined for rn != pc). */ |
| 6521 | return rn_f ? copy_copro_load_store (gdbarch, insn, regs, dsc) |
| 6522 | : copy_undef (gdbarch, insn, dsc); |
| 6523 | |
| 6524 | default: |
| 6525 | return copy_undef (gdbarch, insn, dsc); |
| 6526 | } |
| 6527 | } |
| 6528 | |
| 6529 | case 0xa: |
| 6530 | return copy_unmodified (gdbarch, insn, "stc/stc2", dsc); |
| 6531 | |
| 6532 | case 0xb: |
| 6533 | if (bits (insn, 16, 19) == 0xf) |
| 6534 | /* ldc/ldc2 lit. */ |
| 6535 | return copy_copro_load_store (gdbarch, insn, regs, dsc); |
| 6536 | else |
| 6537 | return copy_undef (gdbarch, insn, dsc); |
| 6538 | |
| 6539 | case 0xc: |
| 6540 | if (bit (insn, 4)) |
| 6541 | return copy_unmodified (gdbarch, insn, "mcr/mcr2", dsc); |
| 6542 | else |
| 6543 | return copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc); |
| 6544 | |
| 6545 | case 0xd: |
| 6546 | if (bit (insn, 4)) |
| 6547 | return copy_unmodified (gdbarch, insn, "mrc/mrc2", dsc); |
| 6548 | else |
| 6549 | return copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc); |
| 6550 | |
| 6551 | default: |
| 6552 | return copy_undef (gdbarch, insn, dsc); |
| 6553 | } |
| 6554 | } |
| 6555 | |
| 6556 | /* Decode miscellaneous instructions in dp/misc encoding space. */ |
| 6557 | |
| 6558 | static int |
| 6559 | decode_miscellaneous (struct gdbarch *gdbarch, uint32_t insn, |
| 6560 | struct regcache *regs, |
| 6561 | struct displaced_step_closure *dsc) |
| 6562 | { |
| 6563 | unsigned int op2 = bits (insn, 4, 6); |
| 6564 | unsigned int op = bits (insn, 21, 22); |
| 6565 | unsigned int op1 = bits (insn, 16, 19); |
| 6566 | |
| 6567 | switch (op2) |
| 6568 | { |
| 6569 | case 0x0: |
| 6570 | return copy_unmodified (gdbarch, insn, "mrs/msr", dsc); |
| 6571 | |
| 6572 | case 0x1: |
| 6573 | if (op == 0x1) /* bx. */ |
| 6574 | return copy_bx_blx_reg (gdbarch, insn, regs, dsc); |
| 6575 | else if (op == 0x3) |
| 6576 | return copy_unmodified (gdbarch, insn, "clz", dsc); |
| 6577 | else |
| 6578 | return copy_undef (gdbarch, insn, dsc); |
| 6579 | |
| 6580 | case 0x2: |
| 6581 | if (op == 0x1) |
| 6582 | /* Not really supported. */ |
| 6583 | return copy_unmodified (gdbarch, insn, "bxj", dsc); |
| 6584 | else |
| 6585 | return copy_undef (gdbarch, insn, dsc); |
| 6586 | |
| 6587 | case 0x3: |
| 6588 | if (op == 0x1) |
| 6589 | return copy_bx_blx_reg (gdbarch, insn, |
| 6590 | regs, dsc); /* blx register. */ |
| 6591 | else |
| 6592 | return copy_undef (gdbarch, insn, dsc); |
| 6593 | |
| 6594 | case 0x5: |
| 6595 | return copy_unmodified (gdbarch, insn, "saturating add/sub", dsc); |
| 6596 | |
| 6597 | case 0x7: |
| 6598 | if (op == 0x1) |
| 6599 | return copy_unmodified (gdbarch, insn, "bkpt", dsc); |
| 6600 | else if (op == 0x3) |
| 6601 | /* Not really supported. */ |
| 6602 | return copy_unmodified (gdbarch, insn, "smc", dsc); |
| 6603 | |
| 6604 | default: |
| 6605 | return copy_undef (gdbarch, insn, dsc); |
| 6606 | } |
| 6607 | } |
| 6608 | |
| 6609 | static int |
| 6610 | decode_dp_misc (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs, |
| 6611 | struct displaced_step_closure *dsc) |
| 6612 | { |
| 6613 | if (bit (insn, 25)) |
| 6614 | switch (bits (insn, 20, 24)) |
| 6615 | { |
| 6616 | case 0x10: |
| 6617 | return copy_unmodified (gdbarch, insn, "movw", dsc); |
| 6618 | |
| 6619 | case 0x14: |
| 6620 | return copy_unmodified (gdbarch, insn, "movt", dsc); |
| 6621 | |
| 6622 | case 0x12: case 0x16: |
| 6623 | return copy_unmodified (gdbarch, insn, "msr imm", dsc); |
| 6624 | |
| 6625 | default: |
| 6626 | return copy_alu_imm (gdbarch, insn, regs, dsc); |
| 6627 | } |
| 6628 | else |
| 6629 | { |
| 6630 | uint32_t op1 = bits (insn, 20, 24), op2 = bits (insn, 4, 7); |
| 6631 | |
| 6632 | if ((op1 & 0x19) != 0x10 && (op2 & 0x1) == 0x0) |
| 6633 | return copy_alu_reg (gdbarch, insn, regs, dsc); |
| 6634 | else if ((op1 & 0x19) != 0x10 && (op2 & 0x9) == 0x1) |
| 6635 | return copy_alu_shifted_reg (gdbarch, insn, regs, dsc); |
| 6636 | else if ((op1 & 0x19) == 0x10 && (op2 & 0x8) == 0x0) |
| 6637 | return decode_miscellaneous (gdbarch, insn, regs, dsc); |
| 6638 | else if ((op1 & 0x19) == 0x10 && (op2 & 0x9) == 0x8) |
| 6639 | return copy_unmodified (gdbarch, insn, "halfword mul/mla", dsc); |
| 6640 | else if ((op1 & 0x10) == 0x00 && op2 == 0x9) |
| 6641 | return copy_unmodified (gdbarch, insn, "mul/mla", dsc); |
| 6642 | else if ((op1 & 0x10) == 0x10 && op2 == 0x9) |
| 6643 | return copy_unmodified (gdbarch, insn, "synch", dsc); |
| 6644 | else if (op2 == 0xb || (op2 & 0xd) == 0xd) |
| 6645 | /* 2nd arg means "unpriveleged". */ |
| 6646 | return copy_extra_ld_st (gdbarch, insn, (op1 & 0x12) == 0x02, regs, |
| 6647 | dsc); |
| 6648 | } |
| 6649 | |
| 6650 | /* Should be unreachable. */ |
| 6651 | return 1; |
| 6652 | } |
| 6653 | |
| 6654 | static int |
| 6655 | decode_ld_st_word_ubyte (struct gdbarch *gdbarch, uint32_t insn, |
| 6656 | struct regcache *regs, |
| 6657 | struct displaced_step_closure *dsc) |
| 6658 | { |
| 6659 | int a = bit (insn, 25), b = bit (insn, 4); |
| 6660 | uint32_t op1 = bits (insn, 20, 24); |
| 6661 | int rn_f = bits (insn, 16, 19) == 0xf; |
| 6662 | |
| 6663 | if ((!a && (op1 & 0x05) == 0x00 && (op1 & 0x17) != 0x02) |
| 6664 | || (a && (op1 & 0x05) == 0x00 && (op1 & 0x17) != 0x02 && !b)) |
| 6665 | return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 0, 0); |
| 6666 | else if ((!a && (op1 & 0x17) == 0x02) |
| 6667 | || (a && (op1 & 0x17) == 0x02 && !b)) |
| 6668 | return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 0, 1); |
| 6669 | else if ((!a && (op1 & 0x05) == 0x01 && (op1 & 0x17) != 0x03) |
| 6670 | || (a && (op1 & 0x05) == 0x01 && (op1 & 0x17) != 0x03 && !b)) |
| 6671 | return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 0, 0); |
| 6672 | else if ((!a && (op1 & 0x17) == 0x03) |
| 6673 | || (a && (op1 & 0x17) == 0x03 && !b)) |
| 6674 | return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 0, 1); |
| 6675 | else if ((!a && (op1 & 0x05) == 0x04 && (op1 & 0x17) != 0x06) |
| 6676 | || (a && (op1 & 0x05) == 0x04 && (op1 & 0x17) != 0x06 && !b)) |
| 6677 | return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 1, 0); |
| 6678 | else if ((!a && (op1 & 0x17) == 0x06) |
| 6679 | || (a && (op1 & 0x17) == 0x06 && !b)) |
| 6680 | return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 1, 1); |
| 6681 | else if ((!a && (op1 & 0x05) == 0x05 && (op1 & 0x17) != 0x07) |
| 6682 | || (a && (op1 & 0x05) == 0x05 && (op1 & 0x17) != 0x07 && !b)) |
| 6683 | return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 1, 0); |
| 6684 | else if ((!a && (op1 & 0x17) == 0x07) |
| 6685 | || (a && (op1 & 0x17) == 0x07 && !b)) |
| 6686 | return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 1, 1); |
| 6687 | |
| 6688 | /* Should be unreachable. */ |
| 6689 | return 1; |
| 6690 | } |
| 6691 | |
| 6692 | static int |
| 6693 | decode_media (struct gdbarch *gdbarch, uint32_t insn, |
| 6694 | struct displaced_step_closure *dsc) |
| 6695 | { |
| 6696 | switch (bits (insn, 20, 24)) |
| 6697 | { |
| 6698 | case 0x00: case 0x01: case 0x02: case 0x03: |
| 6699 | return copy_unmodified (gdbarch, insn, "parallel add/sub signed", dsc); |
| 6700 | |
| 6701 | case 0x04: case 0x05: case 0x06: case 0x07: |
| 6702 | return copy_unmodified (gdbarch, insn, "parallel add/sub unsigned", dsc); |
| 6703 | |
| 6704 | case 0x08: case 0x09: case 0x0a: case 0x0b: |
| 6705 | case 0x0c: case 0x0d: case 0x0e: case 0x0f: |
| 6706 | return copy_unmodified (gdbarch, insn, |
| 6707 | "decode/pack/unpack/saturate/reverse", dsc); |
| 6708 | |
| 6709 | case 0x18: |
| 6710 | if (bits (insn, 5, 7) == 0) /* op2. */ |
| 6711 | { |
| 6712 | if (bits (insn, 12, 15) == 0xf) |
| 6713 | return copy_unmodified (gdbarch, insn, "usad8", dsc); |
| 6714 | else |
| 6715 | return copy_unmodified (gdbarch, insn, "usada8", dsc); |
| 6716 | } |
| 6717 | else |
| 6718 | return copy_undef (gdbarch, insn, dsc); |
| 6719 | |
| 6720 | case 0x1a: case 0x1b: |
| 6721 | if (bits (insn, 5, 6) == 0x2) /* op2[1:0]. */ |
| 6722 | return copy_unmodified (gdbarch, insn, "sbfx", dsc); |
| 6723 | else |
| 6724 | return copy_undef (gdbarch, insn, dsc); |
| 6725 | |
| 6726 | case 0x1c: case 0x1d: |
| 6727 | if (bits (insn, 5, 6) == 0x0) /* op2[1:0]. */ |
| 6728 | { |
| 6729 | if (bits (insn, 0, 3) == 0xf) |
| 6730 | return copy_unmodified (gdbarch, insn, "bfc", dsc); |
| 6731 | else |
| 6732 | return copy_unmodified (gdbarch, insn, "bfi", dsc); |
| 6733 | } |
| 6734 | else |
| 6735 | return copy_undef (gdbarch, insn, dsc); |
| 6736 | |
| 6737 | case 0x1e: case 0x1f: |
| 6738 | if (bits (insn, 5, 6) == 0x2) /* op2[1:0]. */ |
| 6739 | return copy_unmodified (gdbarch, insn, "ubfx", dsc); |
| 6740 | else |
| 6741 | return copy_undef (gdbarch, insn, dsc); |
| 6742 | } |
| 6743 | |
| 6744 | /* Should be unreachable. */ |
| 6745 | return 1; |
| 6746 | } |
| 6747 | |
| 6748 | static int |
| 6749 | decode_b_bl_ldmstm (struct gdbarch *gdbarch, int32_t insn, |
| 6750 | struct regcache *regs, struct displaced_step_closure *dsc) |
| 6751 | { |
| 6752 | if (bit (insn, 25)) |
| 6753 | return copy_b_bl_blx (gdbarch, insn, regs, dsc); |
| 6754 | else |
| 6755 | return copy_block_xfer (gdbarch, insn, regs, dsc); |
| 6756 | } |
| 6757 | |
| 6758 | static int |
| 6759 | decode_ext_reg_ld_st (struct gdbarch *gdbarch, uint32_t insn, |
| 6760 | struct regcache *regs, |
| 6761 | struct displaced_step_closure *dsc) |
| 6762 | { |
| 6763 | unsigned int opcode = bits (insn, 20, 24); |
| 6764 | |
| 6765 | switch (opcode) |
| 6766 | { |
| 6767 | case 0x04: case 0x05: /* VFP/Neon mrrc/mcrr. */ |
| 6768 | return copy_unmodified (gdbarch, insn, "vfp/neon mrrc/mcrr", dsc); |
| 6769 | |
| 6770 | case 0x08: case 0x0a: case 0x0c: case 0x0e: |
| 6771 | case 0x12: case 0x16: |
| 6772 | return copy_unmodified (gdbarch, insn, "vfp/neon vstm/vpush", dsc); |
| 6773 | |
| 6774 | case 0x09: case 0x0b: case 0x0d: case 0x0f: |
| 6775 | case 0x13: case 0x17: |
| 6776 | return copy_unmodified (gdbarch, insn, "vfp/neon vldm/vpop", dsc); |
| 6777 | |
| 6778 | case 0x10: case 0x14: case 0x18: case 0x1c: /* vstr. */ |
| 6779 | case 0x11: case 0x15: case 0x19: case 0x1d: /* vldr. */ |
| 6780 | /* Note: no writeback for these instructions. Bit 25 will always be |
| 6781 | zero though (via caller), so the following works OK. */ |
| 6782 | return copy_copro_load_store (gdbarch, insn, regs, dsc); |
| 6783 | } |
| 6784 | |
| 6785 | /* Should be unreachable. */ |
| 6786 | return 1; |
| 6787 | } |
| 6788 | |
| 6789 | static int |
| 6790 | decode_svc_copro (struct gdbarch *gdbarch, uint32_t insn, CORE_ADDR to, |
| 6791 | struct regcache *regs, struct displaced_step_closure *dsc) |
| 6792 | { |
| 6793 | unsigned int op1 = bits (insn, 20, 25); |
| 6794 | int op = bit (insn, 4); |
| 6795 | unsigned int coproc = bits (insn, 8, 11); |
| 6796 | unsigned int rn = bits (insn, 16, 19); |
| 6797 | |
| 6798 | if ((op1 & 0x20) == 0x00 && (op1 & 0x3a) != 0x00 && (coproc & 0xe) == 0xa) |
| 6799 | return decode_ext_reg_ld_st (gdbarch, insn, regs, dsc); |
| 6800 | else if ((op1 & 0x21) == 0x00 && (op1 & 0x3a) != 0x00 |
| 6801 | && (coproc & 0xe) != 0xa) |
| 6802 | /* stc/stc2. */ |
| 6803 | return copy_copro_load_store (gdbarch, insn, regs, dsc); |
| 6804 | else if ((op1 & 0x21) == 0x01 && (op1 & 0x3a) != 0x00 |
| 6805 | && (coproc & 0xe) != 0xa) |
| 6806 | /* ldc/ldc2 imm/lit. */ |
| 6807 | return copy_copro_load_store (gdbarch, insn, regs, dsc); |
| 6808 | else if ((op1 & 0x3e) == 0x00) |
| 6809 | return copy_undef (gdbarch, insn, dsc); |
| 6810 | else if ((op1 & 0x3e) == 0x04 && (coproc & 0xe) == 0xa) |
| 6811 | return copy_unmodified (gdbarch, insn, "neon 64bit xfer", dsc); |
| 6812 | else if (op1 == 0x04 && (coproc & 0xe) != 0xa) |
| 6813 | return copy_unmodified (gdbarch, insn, "mcrr/mcrr2", dsc); |
| 6814 | else if (op1 == 0x05 && (coproc & 0xe) != 0xa) |
| 6815 | return copy_unmodified (gdbarch, insn, "mrrc/mrrc2", dsc); |
| 6816 | else if ((op1 & 0x30) == 0x20 && !op) |
| 6817 | { |
| 6818 | if ((coproc & 0xe) == 0xa) |
| 6819 | return copy_unmodified (gdbarch, insn, "vfp dataproc", dsc); |
| 6820 | else |
| 6821 | return copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc); |
| 6822 | } |
| 6823 | else if ((op1 & 0x30) == 0x20 && op) |
| 6824 | return copy_unmodified (gdbarch, insn, "neon 8/16/32 bit xfer", dsc); |
| 6825 | else if ((op1 & 0x31) == 0x20 && op && (coproc & 0xe) != 0xa) |
| 6826 | return copy_unmodified (gdbarch, insn, "mcr/mcr2", dsc); |
| 6827 | else if ((op1 & 0x31) == 0x21 && op && (coproc & 0xe) != 0xa) |
| 6828 | return copy_unmodified (gdbarch, insn, "mrc/mrc2", dsc); |
| 6829 | else if ((op1 & 0x30) == 0x30) |
| 6830 | return copy_svc (gdbarch, insn, to, regs, dsc); |
| 6831 | else |
| 6832 | return copy_undef (gdbarch, insn, dsc); /* Possibly unreachable. */ |
| 6833 | } |
| 6834 | |
| 6835 | static void |
| 6836 | thumb_process_displaced_insn (struct gdbarch *gdbarch, CORE_ADDR from, |
| 6837 | CORE_ADDR to, struct regcache *regs, |
| 6838 | struct displaced_step_closure *dsc) |
| 6839 | { |
| 6840 | error (_("Displaced stepping is only supported in ARM mode")); |
| 6841 | } |
| 6842 | |
| 6843 | void |
| 6844 | arm_process_displaced_insn (struct gdbarch *gdbarch, CORE_ADDR from, |
| 6845 | CORE_ADDR to, struct regcache *regs, |
| 6846 | struct displaced_step_closure *dsc) |
| 6847 | { |
| 6848 | int err = 0; |
| 6849 | enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch); |
| 6850 | uint32_t insn; |
| 6851 | |
| 6852 | /* Most displaced instructions use a 1-instruction scratch space, so set this |
| 6853 | here and override below if/when necessary. */ |
| 6854 | dsc->numinsns = 1; |
| 6855 | dsc->insn_addr = from; |
| 6856 | dsc->scratch_base = to; |
| 6857 | dsc->cleanup = NULL; |
| 6858 | dsc->wrote_to_pc = 0; |
| 6859 | |
| 6860 | if (!displaced_in_arm_mode (regs)) |
| 6861 | return thumb_process_displaced_insn (gdbarch, from, to, regs, dsc); |
| 6862 | |
| 6863 | dsc->is_thumb = 0; |
| 6864 | dsc->insn_size = 4; |
| 6865 | insn = read_memory_unsigned_integer (from, 4, byte_order_for_code); |
| 6866 | if (debug_displaced) |
| 6867 | fprintf_unfiltered (gdb_stdlog, "displaced: stepping insn %.8lx " |
| 6868 | "at %.8lx\n", (unsigned long) insn, |
| 6869 | (unsigned long) from); |
| 6870 | |
| 6871 | if ((insn & 0xf0000000) == 0xf0000000) |
| 6872 | err = decode_unconditional (gdbarch, insn, regs, dsc); |
| 6873 | else switch (((insn & 0x10) >> 4) | ((insn & 0xe000000) >> 24)) |
| 6874 | { |
| 6875 | case 0x0: case 0x1: case 0x2: case 0x3: |
| 6876 | err = decode_dp_misc (gdbarch, insn, regs, dsc); |
| 6877 | break; |
| 6878 | |
| 6879 | case 0x4: case 0x5: case 0x6: |
| 6880 | err = decode_ld_st_word_ubyte (gdbarch, insn, regs, dsc); |
| 6881 | break; |
| 6882 | |
| 6883 | case 0x7: |
| 6884 | err = decode_media (gdbarch, insn, dsc); |
| 6885 | break; |
| 6886 | |
| 6887 | case 0x8: case 0x9: case 0xa: case 0xb: |
| 6888 | err = decode_b_bl_ldmstm (gdbarch, insn, regs, dsc); |
| 6889 | break; |
| 6890 | |
| 6891 | case 0xc: case 0xd: case 0xe: case 0xf: |
| 6892 | err = decode_svc_copro (gdbarch, insn, to, regs, dsc); |
| 6893 | break; |
| 6894 | } |
| 6895 | |
| 6896 | if (err) |
| 6897 | internal_error (__FILE__, __LINE__, |
| 6898 | _("arm_process_displaced_insn: Instruction decode error")); |
| 6899 | } |
| 6900 | |
| 6901 | /* Actually set up the scratch space for a displaced instruction. */ |
| 6902 | |
| 6903 | void |
| 6904 | arm_displaced_init_closure (struct gdbarch *gdbarch, CORE_ADDR from, |
| 6905 | CORE_ADDR to, struct displaced_step_closure *dsc) |
| 6906 | { |
| 6907 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 6908 | unsigned int i, len, offset; |
| 6909 | enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch); |
| 6910 | int size = dsc->is_thumb? 2 : 4; |
| 6911 | const unsigned char *bkp_insn; |
| 6912 | |
| 6913 | offset = 0; |
| 6914 | /* Poke modified instruction(s). */ |
| 6915 | for (i = 0; i < dsc->numinsns; i++) |
| 6916 | { |
| 6917 | if (debug_displaced) |
| 6918 | { |
| 6919 | fprintf_unfiltered (gdb_stdlog, "displaced: writing insn "); |
| 6920 | if (size == 4) |
| 6921 | fprintf_unfiltered (gdb_stdlog, "%.8lx", |
| 6922 | dsc->modinsn[i]); |
| 6923 | else if (size == 2) |
| 6924 | fprintf_unfiltered (gdb_stdlog, "%.4x", |
| 6925 | (unsigned short)dsc->modinsn[i]); |
| 6926 | |
| 6927 | fprintf_unfiltered (gdb_stdlog, " at %.8lx\n", |
| 6928 | (unsigned long) to + offset); |
| 6929 | |
| 6930 | } |
| 6931 | write_memory_unsigned_integer (to + offset, size, |
| 6932 | byte_order_for_code, |
| 6933 | dsc->modinsn[i]); |
| 6934 | offset += size; |
| 6935 | } |
| 6936 | |
| 6937 | /* Choose the correct breakpoint instruction. */ |
| 6938 | if (dsc->is_thumb) |
| 6939 | { |
| 6940 | bkp_insn = tdep->thumb_breakpoint; |
| 6941 | len = tdep->thumb_breakpoint_size; |
| 6942 | } |
| 6943 | else |
| 6944 | { |
| 6945 | bkp_insn = tdep->arm_breakpoint; |
| 6946 | len = tdep->arm_breakpoint_size; |
| 6947 | } |
| 6948 | |
| 6949 | /* Put breakpoint afterwards. */ |
| 6950 | write_memory (to + offset, bkp_insn, len); |
| 6951 | |
| 6952 | if (debug_displaced) |
| 6953 | fprintf_unfiltered (gdb_stdlog, "displaced: copy %s->%s: ", |
| 6954 | paddress (gdbarch, from), paddress (gdbarch, to)); |
| 6955 | } |
| 6956 | |
| 6957 | /* Entry point for copying an instruction into scratch space for displaced |
| 6958 | stepping. */ |
| 6959 | |
| 6960 | struct displaced_step_closure * |
| 6961 | arm_displaced_step_copy_insn (struct gdbarch *gdbarch, |
| 6962 | CORE_ADDR from, CORE_ADDR to, |
| 6963 | struct regcache *regs) |
| 6964 | { |
| 6965 | struct displaced_step_closure *dsc |
| 6966 | = xmalloc (sizeof (struct displaced_step_closure)); |
| 6967 | arm_process_displaced_insn (gdbarch, from, to, regs, dsc); |
| 6968 | arm_displaced_init_closure (gdbarch, from, to, dsc); |
| 6969 | |
| 6970 | return dsc; |
| 6971 | } |
| 6972 | |
| 6973 | /* Entry point for cleaning things up after a displaced instruction has been |
| 6974 | single-stepped. */ |
| 6975 | |
| 6976 | void |
| 6977 | arm_displaced_step_fixup (struct gdbarch *gdbarch, |
| 6978 | struct displaced_step_closure *dsc, |
| 6979 | CORE_ADDR from, CORE_ADDR to, |
| 6980 | struct regcache *regs) |
| 6981 | { |
| 6982 | if (dsc->cleanup) |
| 6983 | dsc->cleanup (gdbarch, regs, dsc); |
| 6984 | |
| 6985 | if (!dsc->wrote_to_pc) |
| 6986 | regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, |
| 6987 | dsc->insn_addr + dsc->insn_size); |
| 6988 | |
| 6989 | } |
| 6990 | |
| 6991 | #include "bfd-in2.h" |
| 6992 | #include "libcoff.h" |
| 6993 | |
| 6994 | static int |
| 6995 | gdb_print_insn_arm (bfd_vma memaddr, disassemble_info *info) |
| 6996 | { |
| 6997 | struct gdbarch *gdbarch = info->application_data; |
| 6998 | |
| 6999 | if (arm_pc_is_thumb (gdbarch, memaddr)) |
| 7000 | { |
| 7001 | static asymbol *asym; |
| 7002 | static combined_entry_type ce; |
| 7003 | static struct coff_symbol_struct csym; |
| 7004 | static struct bfd fake_bfd; |
| 7005 | static bfd_target fake_target; |
| 7006 | |
| 7007 | if (csym.native == NULL) |
| 7008 | { |
| 7009 | /* Create a fake symbol vector containing a Thumb symbol. |
| 7010 | This is solely so that the code in print_insn_little_arm() |
| 7011 | and print_insn_big_arm() in opcodes/arm-dis.c will detect |
| 7012 | the presence of a Thumb symbol and switch to decoding |
| 7013 | Thumb instructions. */ |
| 7014 | |
| 7015 | fake_target.flavour = bfd_target_coff_flavour; |
| 7016 | fake_bfd.xvec = &fake_target; |
| 7017 | ce.u.syment.n_sclass = C_THUMBEXTFUNC; |
| 7018 | csym.native = &ce; |
| 7019 | csym.symbol.the_bfd = &fake_bfd; |
| 7020 | csym.symbol.name = "fake"; |
| 7021 | asym = (asymbol *) & csym; |
| 7022 | } |
| 7023 | |
| 7024 | memaddr = UNMAKE_THUMB_ADDR (memaddr); |
| 7025 | info->symbols = &asym; |
| 7026 | } |
| 7027 | else |
| 7028 | info->symbols = NULL; |
| 7029 | |
| 7030 | if (info->endian == BFD_ENDIAN_BIG) |
| 7031 | return print_insn_big_arm (memaddr, info); |
| 7032 | else |
| 7033 | return print_insn_little_arm (memaddr, info); |
| 7034 | } |
| 7035 | |
| 7036 | /* The following define instruction sequences that will cause ARM |
| 7037 | cpu's to take an undefined instruction trap. These are used to |
| 7038 | signal a breakpoint to GDB. |
| 7039 | |
| 7040 | The newer ARMv4T cpu's are capable of operating in ARM or Thumb |
| 7041 | modes. A different instruction is required for each mode. The ARM |
| 7042 | cpu's can also be big or little endian. Thus four different |
| 7043 | instructions are needed to support all cases. |
| 7044 | |
| 7045 | Note: ARMv4 defines several new instructions that will take the |
| 7046 | undefined instruction trap. ARM7TDMI is nominally ARMv4T, but does |
| 7047 | not in fact add the new instructions. The new undefined |
| 7048 | instructions in ARMv4 are all instructions that had no defined |
| 7049 | behaviour in earlier chips. There is no guarantee that they will |
| 7050 | raise an exception, but may be treated as NOP's. In practice, it |
| 7051 | may only safe to rely on instructions matching: |
| 7052 | |
| 7053 | 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 |
| 7054 | 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 |
| 7055 | C C C C 0 1 1 x x x x x x x x x x x x x x x x x x x x 1 x x x x |
| 7056 | |
| 7057 | Even this may only true if the condition predicate is true. The |
| 7058 | following use a condition predicate of ALWAYS so it is always TRUE. |
| 7059 | |
| 7060 | There are other ways of forcing a breakpoint. GNU/Linux, RISC iX, |
| 7061 | and NetBSD all use a software interrupt rather than an undefined |
| 7062 | instruction to force a trap. This can be handled by by the |
| 7063 | abi-specific code during establishment of the gdbarch vector. */ |
| 7064 | |
| 7065 | #define ARM_LE_BREAKPOINT {0xFE,0xDE,0xFF,0xE7} |
| 7066 | #define ARM_BE_BREAKPOINT {0xE7,0xFF,0xDE,0xFE} |
| 7067 | #define THUMB_LE_BREAKPOINT {0xbe,0xbe} |
| 7068 | #define THUMB_BE_BREAKPOINT {0xbe,0xbe} |
| 7069 | |
| 7070 | static const char arm_default_arm_le_breakpoint[] = ARM_LE_BREAKPOINT; |
| 7071 | static const char arm_default_arm_be_breakpoint[] = ARM_BE_BREAKPOINT; |
| 7072 | static const char arm_default_thumb_le_breakpoint[] = THUMB_LE_BREAKPOINT; |
| 7073 | static const char arm_default_thumb_be_breakpoint[] = THUMB_BE_BREAKPOINT; |
| 7074 | |
| 7075 | /* Determine the type and size of breakpoint to insert at PCPTR. Uses |
| 7076 | the program counter value to determine whether a 16-bit or 32-bit |
| 7077 | breakpoint should be used. It returns a pointer to a string of |
| 7078 | bytes that encode a breakpoint instruction, stores the length of |
| 7079 | the string to *lenptr, and adjusts the program counter (if |
| 7080 | necessary) to point to the actual memory location where the |
| 7081 | breakpoint should be inserted. */ |
| 7082 | |
| 7083 | static const unsigned char * |
| 7084 | arm_breakpoint_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pcptr, int *lenptr) |
| 7085 | { |
| 7086 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 7087 | enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch); |
| 7088 | |
| 7089 | if (arm_pc_is_thumb (gdbarch, *pcptr)) |
| 7090 | { |
| 7091 | *pcptr = UNMAKE_THUMB_ADDR (*pcptr); |
| 7092 | |
| 7093 | /* If we have a separate 32-bit breakpoint instruction for Thumb-2, |
| 7094 | check whether we are replacing a 32-bit instruction. */ |
| 7095 | if (tdep->thumb2_breakpoint != NULL) |
| 7096 | { |
| 7097 | gdb_byte buf[2]; |
| 7098 | if (target_read_memory (*pcptr, buf, 2) == 0) |
| 7099 | { |
| 7100 | unsigned short inst1; |
| 7101 | inst1 = extract_unsigned_integer (buf, 2, byte_order_for_code); |
| 7102 | if ((inst1 & 0xe000) == 0xe000 && (inst1 & 0x1800) != 0) |
| 7103 | { |
| 7104 | *lenptr = tdep->thumb2_breakpoint_size; |
| 7105 | return tdep->thumb2_breakpoint; |
| 7106 | } |
| 7107 | } |
| 7108 | } |
| 7109 | |
| 7110 | *lenptr = tdep->thumb_breakpoint_size; |
| 7111 | return tdep->thumb_breakpoint; |
| 7112 | } |
| 7113 | else |
| 7114 | { |
| 7115 | *lenptr = tdep->arm_breakpoint_size; |
| 7116 | return tdep->arm_breakpoint; |
| 7117 | } |
| 7118 | } |
| 7119 | |
| 7120 | static void |
| 7121 | arm_remote_breakpoint_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pcptr, |
| 7122 | int *kindptr) |
| 7123 | { |
| 7124 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 7125 | |
| 7126 | arm_breakpoint_from_pc (gdbarch, pcptr, kindptr); |
| 7127 | |
| 7128 | if (arm_pc_is_thumb (gdbarch, *pcptr) && *kindptr == 4) |
| 7129 | /* The documented magic value for a 32-bit Thumb-2 breakpoint, so |
| 7130 | that this is not confused with a 32-bit ARM breakpoint. */ |
| 7131 | *kindptr = 3; |
| 7132 | } |
| 7133 | |
| 7134 | /* Extract from an array REGBUF containing the (raw) register state a |
| 7135 | function return value of type TYPE, and copy that, in virtual |
| 7136 | format, into VALBUF. */ |
| 7137 | |
| 7138 | static void |
| 7139 | arm_extract_return_value (struct type *type, struct regcache *regs, |
| 7140 | gdb_byte *valbuf) |
| 7141 | { |
| 7142 | struct gdbarch *gdbarch = get_regcache_arch (regs); |
| 7143 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 7144 | |
| 7145 | if (TYPE_CODE_FLT == TYPE_CODE (type)) |
| 7146 | { |
| 7147 | switch (gdbarch_tdep (gdbarch)->fp_model) |
| 7148 | { |
| 7149 | case ARM_FLOAT_FPA: |
| 7150 | { |
| 7151 | /* The value is in register F0 in internal format. We need to |
| 7152 | extract the raw value and then convert it to the desired |
| 7153 | internal type. */ |
| 7154 | bfd_byte tmpbuf[FP_REGISTER_SIZE]; |
| 7155 | |
| 7156 | regcache_cooked_read (regs, ARM_F0_REGNUM, tmpbuf); |
| 7157 | convert_from_extended (floatformat_from_type (type), tmpbuf, |
| 7158 | valbuf, gdbarch_byte_order (gdbarch)); |
| 7159 | } |
| 7160 | break; |
| 7161 | |
| 7162 | case ARM_FLOAT_SOFT_FPA: |
| 7163 | case ARM_FLOAT_SOFT_VFP: |
| 7164 | /* ARM_FLOAT_VFP can arise if this is a variadic function so |
| 7165 | not using the VFP ABI code. */ |
| 7166 | case ARM_FLOAT_VFP: |
| 7167 | regcache_cooked_read (regs, ARM_A1_REGNUM, valbuf); |
| 7168 | if (TYPE_LENGTH (type) > 4) |
| 7169 | regcache_cooked_read (regs, ARM_A1_REGNUM + 1, |
| 7170 | valbuf + INT_REGISTER_SIZE); |
| 7171 | break; |
| 7172 | |
| 7173 | default: |
| 7174 | internal_error (__FILE__, __LINE__, |
| 7175 | _("arm_extract_return_value: " |
| 7176 | "Floating point model not supported")); |
| 7177 | break; |
| 7178 | } |
| 7179 | } |
| 7180 | else if (TYPE_CODE (type) == TYPE_CODE_INT |
| 7181 | || TYPE_CODE (type) == TYPE_CODE_CHAR |
| 7182 | || TYPE_CODE (type) == TYPE_CODE_BOOL |
| 7183 | || TYPE_CODE (type) == TYPE_CODE_PTR |
| 7184 | || TYPE_CODE (type) == TYPE_CODE_REF |
| 7185 | || TYPE_CODE (type) == TYPE_CODE_ENUM) |
| 7186 | { |
| 7187 | /* If the type is a plain integer, then the access is |
| 7188 | straight-forward. Otherwise we have to play around a bit |
| 7189 | more. */ |
| 7190 | int len = TYPE_LENGTH (type); |
| 7191 | int regno = ARM_A1_REGNUM; |
| 7192 | ULONGEST tmp; |
| 7193 | |
| 7194 | while (len > 0) |
| 7195 | { |
| 7196 | /* By using store_unsigned_integer we avoid having to do |
| 7197 | anything special for small big-endian values. */ |
| 7198 | regcache_cooked_read_unsigned (regs, regno++, &tmp); |
| 7199 | store_unsigned_integer (valbuf, |
| 7200 | (len > INT_REGISTER_SIZE |
| 7201 | ? INT_REGISTER_SIZE : len), |
| 7202 | byte_order, tmp); |
| 7203 | len -= INT_REGISTER_SIZE; |
| 7204 | valbuf += INT_REGISTER_SIZE; |
| 7205 | } |
| 7206 | } |
| 7207 | else |
| 7208 | { |
| 7209 | /* For a structure or union the behaviour is as if the value had |
| 7210 | been stored to word-aligned memory and then loaded into |
| 7211 | registers with 32-bit load instruction(s). */ |
| 7212 | int len = TYPE_LENGTH (type); |
| 7213 | int regno = ARM_A1_REGNUM; |
| 7214 | bfd_byte tmpbuf[INT_REGISTER_SIZE]; |
| 7215 | |
| 7216 | while (len > 0) |
| 7217 | { |
| 7218 | regcache_cooked_read (regs, regno++, tmpbuf); |
| 7219 | memcpy (valbuf, tmpbuf, |
| 7220 | len > INT_REGISTER_SIZE ? INT_REGISTER_SIZE : len); |
| 7221 | len -= INT_REGISTER_SIZE; |
| 7222 | valbuf += INT_REGISTER_SIZE; |
| 7223 | } |
| 7224 | } |
| 7225 | } |
| 7226 | |
| 7227 | |
| 7228 | /* Will a function return an aggregate type in memory or in a |
| 7229 | register? Return 0 if an aggregate type can be returned in a |
| 7230 | register, 1 if it must be returned in memory. */ |
| 7231 | |
| 7232 | static int |
| 7233 | arm_return_in_memory (struct gdbarch *gdbarch, struct type *type) |
| 7234 | { |
| 7235 | int nRc; |
| 7236 | enum type_code code; |
| 7237 | |
| 7238 | CHECK_TYPEDEF (type); |
| 7239 | |
| 7240 | /* In the ARM ABI, "integer" like aggregate types are returned in |
| 7241 | registers. For an aggregate type to be integer like, its size |
| 7242 | must be less than or equal to INT_REGISTER_SIZE and the |
| 7243 | offset of each addressable subfield must be zero. Note that bit |
| 7244 | fields are not addressable, and all addressable subfields of |
| 7245 | unions always start at offset zero. |
| 7246 | |
| 7247 | This function is based on the behaviour of GCC 2.95.1. |
| 7248 | See: gcc/arm.c: arm_return_in_memory() for details. |
| 7249 | |
| 7250 | Note: All versions of GCC before GCC 2.95.2 do not set up the |
| 7251 | parameters correctly for a function returning the following |
| 7252 | structure: struct { float f;}; This should be returned in memory, |
| 7253 | not a register. Richard Earnshaw sent me a patch, but I do not |
| 7254 | know of any way to detect if a function like the above has been |
| 7255 | compiled with the correct calling convention. */ |
| 7256 | |
| 7257 | /* All aggregate types that won't fit in a register must be returned |
| 7258 | in memory. */ |
| 7259 | if (TYPE_LENGTH (type) > INT_REGISTER_SIZE) |
| 7260 | { |
| 7261 | return 1; |
| 7262 | } |
| 7263 | |
| 7264 | /* The AAPCS says all aggregates not larger than a word are returned |
| 7265 | in a register. */ |
| 7266 | if (gdbarch_tdep (gdbarch)->arm_abi != ARM_ABI_APCS) |
| 7267 | return 0; |
| 7268 | |
| 7269 | /* The only aggregate types that can be returned in a register are |
| 7270 | structs and unions. Arrays must be returned in memory. */ |
| 7271 | code = TYPE_CODE (type); |
| 7272 | if ((TYPE_CODE_STRUCT != code) && (TYPE_CODE_UNION != code)) |
| 7273 | { |
| 7274 | return 1; |
| 7275 | } |
| 7276 | |
| 7277 | /* Assume all other aggregate types can be returned in a register. |
| 7278 | Run a check for structures, unions and arrays. */ |
| 7279 | nRc = 0; |
| 7280 | |
| 7281 | if ((TYPE_CODE_STRUCT == code) || (TYPE_CODE_UNION == code)) |
| 7282 | { |
| 7283 | int i; |
| 7284 | /* Need to check if this struct/union is "integer" like. For |
| 7285 | this to be true, its size must be less than or equal to |
| 7286 | INT_REGISTER_SIZE and the offset of each addressable |
| 7287 | subfield must be zero. Note that bit fields are not |
| 7288 | addressable, and unions always start at offset zero. If any |
| 7289 | of the subfields is a floating point type, the struct/union |
| 7290 | cannot be an integer type. */ |
| 7291 | |
| 7292 | /* For each field in the object, check: |
| 7293 | 1) Is it FP? --> yes, nRc = 1; |
| 7294 | 2) Is it addressable (bitpos != 0) and |
| 7295 | not packed (bitsize == 0)? |
| 7296 | --> yes, nRc = 1 |
| 7297 | */ |
| 7298 | |
| 7299 | for (i = 0; i < TYPE_NFIELDS (type); i++) |
| 7300 | { |
| 7301 | enum type_code field_type_code; |
| 7302 | field_type_code = TYPE_CODE (check_typedef (TYPE_FIELD_TYPE (type, |
| 7303 | i))); |
| 7304 | |
| 7305 | /* Is it a floating point type field? */ |
| 7306 | if (field_type_code == TYPE_CODE_FLT) |
| 7307 | { |
| 7308 | nRc = 1; |
| 7309 | break; |
| 7310 | } |
| 7311 | |
| 7312 | /* If bitpos != 0, then we have to care about it. */ |
| 7313 | if (TYPE_FIELD_BITPOS (type, i) != 0) |
| 7314 | { |
| 7315 | /* Bitfields are not addressable. If the field bitsize is |
| 7316 | zero, then the field is not packed. Hence it cannot be |
| 7317 | a bitfield or any other packed type. */ |
| 7318 | if (TYPE_FIELD_BITSIZE (type, i) == 0) |
| 7319 | { |
| 7320 | nRc = 1; |
| 7321 | break; |
| 7322 | } |
| 7323 | } |
| 7324 | } |
| 7325 | } |
| 7326 | |
| 7327 | return nRc; |
| 7328 | } |
| 7329 | |
| 7330 | /* Write into appropriate registers a function return value of type |
| 7331 | TYPE, given in virtual format. */ |
| 7332 | |
| 7333 | static void |
| 7334 | arm_store_return_value (struct type *type, struct regcache *regs, |
| 7335 | const gdb_byte *valbuf) |
| 7336 | { |
| 7337 | struct gdbarch *gdbarch = get_regcache_arch (regs); |
| 7338 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 7339 | |
| 7340 | if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| 7341 | { |
| 7342 | char buf[MAX_REGISTER_SIZE]; |
| 7343 | |
| 7344 | switch (gdbarch_tdep (gdbarch)->fp_model) |
| 7345 | { |
| 7346 | case ARM_FLOAT_FPA: |
| 7347 | |
| 7348 | convert_to_extended (floatformat_from_type (type), buf, valbuf, |
| 7349 | gdbarch_byte_order (gdbarch)); |
| 7350 | regcache_cooked_write (regs, ARM_F0_REGNUM, buf); |
| 7351 | break; |
| 7352 | |
| 7353 | case ARM_FLOAT_SOFT_FPA: |
| 7354 | case ARM_FLOAT_SOFT_VFP: |
| 7355 | /* ARM_FLOAT_VFP can arise if this is a variadic function so |
| 7356 | not using the VFP ABI code. */ |
| 7357 | case ARM_FLOAT_VFP: |
| 7358 | regcache_cooked_write (regs, ARM_A1_REGNUM, valbuf); |
| 7359 | if (TYPE_LENGTH (type) > 4) |
| 7360 | regcache_cooked_write (regs, ARM_A1_REGNUM + 1, |
| 7361 | valbuf + INT_REGISTER_SIZE); |
| 7362 | break; |
| 7363 | |
| 7364 | default: |
| 7365 | internal_error (__FILE__, __LINE__, |
| 7366 | _("arm_store_return_value: Floating " |
| 7367 | "point model not supported")); |
| 7368 | break; |
| 7369 | } |
| 7370 | } |
| 7371 | else if (TYPE_CODE (type) == TYPE_CODE_INT |
| 7372 | || TYPE_CODE (type) == TYPE_CODE_CHAR |
| 7373 | || TYPE_CODE (type) == TYPE_CODE_BOOL |
| 7374 | || TYPE_CODE (type) == TYPE_CODE_PTR |
| 7375 | || TYPE_CODE (type) == TYPE_CODE_REF |
| 7376 | || TYPE_CODE (type) == TYPE_CODE_ENUM) |
| 7377 | { |
| 7378 | if (TYPE_LENGTH (type) <= 4) |
| 7379 | { |
| 7380 | /* Values of one word or less are zero/sign-extended and |
| 7381 | returned in r0. */ |
| 7382 | bfd_byte tmpbuf[INT_REGISTER_SIZE]; |
| 7383 | LONGEST val = unpack_long (type, valbuf); |
| 7384 | |
| 7385 | store_signed_integer (tmpbuf, INT_REGISTER_SIZE, byte_order, val); |
| 7386 | regcache_cooked_write (regs, ARM_A1_REGNUM, tmpbuf); |
| 7387 | } |
| 7388 | else |
| 7389 | { |
| 7390 | /* Integral values greater than one word are stored in consecutive |
| 7391 | registers starting with r0. This will always be a multiple of |
| 7392 | the regiser size. */ |
| 7393 | int len = TYPE_LENGTH (type); |
| 7394 | int regno = ARM_A1_REGNUM; |
| 7395 | |
| 7396 | while (len > 0) |
| 7397 | { |
| 7398 | regcache_cooked_write (regs, regno++, valbuf); |
| 7399 | len -= INT_REGISTER_SIZE; |
| 7400 | valbuf += INT_REGISTER_SIZE; |
| 7401 | } |
| 7402 | } |
| 7403 | } |
| 7404 | else |
| 7405 | { |
| 7406 | /* For a structure or union the behaviour is as if the value had |
| 7407 | been stored to word-aligned memory and then loaded into |
| 7408 | registers with 32-bit load instruction(s). */ |
| 7409 | int len = TYPE_LENGTH (type); |
| 7410 | int regno = ARM_A1_REGNUM; |
| 7411 | bfd_byte tmpbuf[INT_REGISTER_SIZE]; |
| 7412 | |
| 7413 | while (len > 0) |
| 7414 | { |
| 7415 | memcpy (tmpbuf, valbuf, |
| 7416 | len > INT_REGISTER_SIZE ? INT_REGISTER_SIZE : len); |
| 7417 | regcache_cooked_write (regs, regno++, tmpbuf); |
| 7418 | len -= INT_REGISTER_SIZE; |
| 7419 | valbuf += INT_REGISTER_SIZE; |
| 7420 | } |
| 7421 | } |
| 7422 | } |
| 7423 | |
| 7424 | |
| 7425 | /* Handle function return values. */ |
| 7426 | |
| 7427 | static enum return_value_convention |
| 7428 | arm_return_value (struct gdbarch *gdbarch, struct type *func_type, |
| 7429 | struct type *valtype, struct regcache *regcache, |
| 7430 | gdb_byte *readbuf, const gdb_byte *writebuf) |
| 7431 | { |
| 7432 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 7433 | enum arm_vfp_cprc_base_type vfp_base_type; |
| 7434 | int vfp_base_count; |
| 7435 | |
| 7436 | if (arm_vfp_abi_for_function (gdbarch, func_type) |
| 7437 | && arm_vfp_call_candidate (valtype, &vfp_base_type, &vfp_base_count)) |
| 7438 | { |
| 7439 | int reg_char = arm_vfp_cprc_reg_char (vfp_base_type); |
| 7440 | int unit_length = arm_vfp_cprc_unit_length (vfp_base_type); |
| 7441 | int i; |
| 7442 | for (i = 0; i < vfp_base_count; i++) |
| 7443 | { |
| 7444 | if (reg_char == 'q') |
| 7445 | { |
| 7446 | if (writebuf) |
| 7447 | arm_neon_quad_write (gdbarch, regcache, i, |
| 7448 | writebuf + i * unit_length); |
| 7449 | |
| 7450 | if (readbuf) |
| 7451 | arm_neon_quad_read (gdbarch, regcache, i, |
| 7452 | readbuf + i * unit_length); |
| 7453 | } |
| 7454 | else |
| 7455 | { |
| 7456 | char name_buf[4]; |
| 7457 | int regnum; |
| 7458 | |
| 7459 | sprintf (name_buf, "%c%d", reg_char, i); |
| 7460 | regnum = user_reg_map_name_to_regnum (gdbarch, name_buf, |
| 7461 | strlen (name_buf)); |
| 7462 | if (writebuf) |
| 7463 | regcache_cooked_write (regcache, regnum, |
| 7464 | writebuf + i * unit_length); |
| 7465 | if (readbuf) |
| 7466 | regcache_cooked_read (regcache, regnum, |
| 7467 | readbuf + i * unit_length); |
| 7468 | } |
| 7469 | } |
| 7470 | return RETURN_VALUE_REGISTER_CONVENTION; |
| 7471 | } |
| 7472 | |
| 7473 | if (TYPE_CODE (valtype) == TYPE_CODE_STRUCT |
| 7474 | || TYPE_CODE (valtype) == TYPE_CODE_UNION |
| 7475 | || TYPE_CODE (valtype) == TYPE_CODE_ARRAY) |
| 7476 | { |
| 7477 | if (tdep->struct_return == pcc_struct_return |
| 7478 | || arm_return_in_memory (gdbarch, valtype)) |
| 7479 | return RETURN_VALUE_STRUCT_CONVENTION; |
| 7480 | } |
| 7481 | |
| 7482 | if (writebuf) |
| 7483 | arm_store_return_value (valtype, regcache, writebuf); |
| 7484 | |
| 7485 | if (readbuf) |
| 7486 | arm_extract_return_value (valtype, regcache, readbuf); |
| 7487 | |
| 7488 | return RETURN_VALUE_REGISTER_CONVENTION; |
| 7489 | } |
| 7490 | |
| 7491 | |
| 7492 | static int |
| 7493 | arm_get_longjmp_target (struct frame_info *frame, CORE_ADDR *pc) |
| 7494 | { |
| 7495 | struct gdbarch *gdbarch = get_frame_arch (frame); |
| 7496 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 7497 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 7498 | CORE_ADDR jb_addr; |
| 7499 | char buf[INT_REGISTER_SIZE]; |
| 7500 | |
| 7501 | jb_addr = get_frame_register_unsigned (frame, ARM_A1_REGNUM); |
| 7502 | |
| 7503 | if (target_read_memory (jb_addr + tdep->jb_pc * tdep->jb_elt_size, buf, |
| 7504 | INT_REGISTER_SIZE)) |
| 7505 | return 0; |
| 7506 | |
| 7507 | *pc = extract_unsigned_integer (buf, INT_REGISTER_SIZE, byte_order); |
| 7508 | return 1; |
| 7509 | } |
| 7510 | |
| 7511 | /* Recognize GCC and GNU ld's trampolines. If we are in a trampoline, |
| 7512 | return the target PC. Otherwise return 0. */ |
| 7513 | |
| 7514 | CORE_ADDR |
| 7515 | arm_skip_stub (struct frame_info *frame, CORE_ADDR pc) |
| 7516 | { |
| 7517 | char *name; |
| 7518 | int namelen; |
| 7519 | CORE_ADDR start_addr; |
| 7520 | |
| 7521 | /* Find the starting address and name of the function containing the PC. */ |
| 7522 | if (find_pc_partial_function (pc, &name, &start_addr, NULL) == 0) |
| 7523 | return 0; |
| 7524 | |
| 7525 | /* If PC is in a Thumb call or return stub, return the address of the |
| 7526 | target PC, which is in a register. The thunk functions are called |
| 7527 | _call_via_xx, where x is the register name. The possible names |
| 7528 | are r0-r9, sl, fp, ip, sp, and lr. ARM RealView has similar |
| 7529 | functions, named __ARM_call_via_r[0-7]. */ |
| 7530 | if (strncmp (name, "_call_via_", 10) == 0 |
| 7531 | || strncmp (name, "__ARM_call_via_", strlen ("__ARM_call_via_")) == 0) |
| 7532 | { |
| 7533 | /* Use the name suffix to determine which register contains the |
| 7534 | target PC. */ |
| 7535 | static char *table[15] = |
| 7536 | {"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", |
| 7537 | "r8", "r9", "sl", "fp", "ip", "sp", "lr" |
| 7538 | }; |
| 7539 | int regno; |
| 7540 | int offset = strlen (name) - 2; |
| 7541 | |
| 7542 | for (regno = 0; regno <= 14; regno++) |
| 7543 | if (strcmp (&name[offset], table[regno]) == 0) |
| 7544 | return get_frame_register_unsigned (frame, regno); |
| 7545 | } |
| 7546 | |
| 7547 | /* GNU ld generates __foo_from_arm or __foo_from_thumb for |
| 7548 | non-interworking calls to foo. We could decode the stubs |
| 7549 | to find the target but it's easier to use the symbol table. */ |
| 7550 | namelen = strlen (name); |
| 7551 | if (name[0] == '_' && name[1] == '_' |
| 7552 | && ((namelen > 2 + strlen ("_from_thumb") |
| 7553 | && strncmp (name + namelen - strlen ("_from_thumb"), "_from_thumb", |
| 7554 | strlen ("_from_thumb")) == 0) |
| 7555 | || (namelen > 2 + strlen ("_from_arm") |
| 7556 | && strncmp (name + namelen - strlen ("_from_arm"), "_from_arm", |
| 7557 | strlen ("_from_arm")) == 0))) |
| 7558 | { |
| 7559 | char *target_name; |
| 7560 | int target_len = namelen - 2; |
| 7561 | struct minimal_symbol *minsym; |
| 7562 | struct objfile *objfile; |
| 7563 | struct obj_section *sec; |
| 7564 | |
| 7565 | if (name[namelen - 1] == 'b') |
| 7566 | target_len -= strlen ("_from_thumb"); |
| 7567 | else |
| 7568 | target_len -= strlen ("_from_arm"); |
| 7569 | |
| 7570 | target_name = alloca (target_len + 1); |
| 7571 | memcpy (target_name, name + 2, target_len); |
| 7572 | target_name[target_len] = '\0'; |
| 7573 | |
| 7574 | sec = find_pc_section (pc); |
| 7575 | objfile = (sec == NULL) ? NULL : sec->objfile; |
| 7576 | minsym = lookup_minimal_symbol (target_name, NULL, objfile); |
| 7577 | if (minsym != NULL) |
| 7578 | return SYMBOL_VALUE_ADDRESS (minsym); |
| 7579 | else |
| 7580 | return 0; |
| 7581 | } |
| 7582 | |
| 7583 | return 0; /* not a stub */ |
| 7584 | } |
| 7585 | |
| 7586 | static void |
| 7587 | set_arm_command (char *args, int from_tty) |
| 7588 | { |
| 7589 | printf_unfiltered (_("\ |
| 7590 | \"set arm\" must be followed by an apporpriate subcommand.\n")); |
| 7591 | help_list (setarmcmdlist, "set arm ", all_commands, gdb_stdout); |
| 7592 | } |
| 7593 | |
| 7594 | static void |
| 7595 | show_arm_command (char *args, int from_tty) |
| 7596 | { |
| 7597 | cmd_show_list (showarmcmdlist, from_tty, ""); |
| 7598 | } |
| 7599 | |
| 7600 | static void |
| 7601 | arm_update_current_architecture (void) |
| 7602 | { |
| 7603 | struct gdbarch_info info; |
| 7604 | |
| 7605 | /* If the current architecture is not ARM, we have nothing to do. */ |
| 7606 | if (gdbarch_bfd_arch_info (target_gdbarch)->arch != bfd_arch_arm) |
| 7607 | return; |
| 7608 | |
| 7609 | /* Update the architecture. */ |
| 7610 | gdbarch_info_init (&info); |
| 7611 | |
| 7612 | if (!gdbarch_update_p (info)) |
| 7613 | internal_error (__FILE__, __LINE__, _("could not update architecture")); |
| 7614 | } |
| 7615 | |
| 7616 | static void |
| 7617 | set_fp_model_sfunc (char *args, int from_tty, |
| 7618 | struct cmd_list_element *c) |
| 7619 | { |
| 7620 | enum arm_float_model fp_model; |
| 7621 | |
| 7622 | for (fp_model = ARM_FLOAT_AUTO; fp_model != ARM_FLOAT_LAST; fp_model++) |
| 7623 | if (strcmp (current_fp_model, fp_model_strings[fp_model]) == 0) |
| 7624 | { |
| 7625 | arm_fp_model = fp_model; |
| 7626 | break; |
| 7627 | } |
| 7628 | |
| 7629 | if (fp_model == ARM_FLOAT_LAST) |
| 7630 | internal_error (__FILE__, __LINE__, _("Invalid fp model accepted: %s."), |
| 7631 | current_fp_model); |
| 7632 | |
| 7633 | arm_update_current_architecture (); |
| 7634 | } |
| 7635 | |
| 7636 | static void |
| 7637 | show_fp_model (struct ui_file *file, int from_tty, |
| 7638 | struct cmd_list_element *c, const char *value) |
| 7639 | { |
| 7640 | struct gdbarch_tdep *tdep = gdbarch_tdep (target_gdbarch); |
| 7641 | |
| 7642 | if (arm_fp_model == ARM_FLOAT_AUTO |
| 7643 | && gdbarch_bfd_arch_info (target_gdbarch)->arch == bfd_arch_arm) |
| 7644 | fprintf_filtered (file, _("\ |
| 7645 | The current ARM floating point model is \"auto\" (currently \"%s\").\n"), |
| 7646 | fp_model_strings[tdep->fp_model]); |
| 7647 | else |
| 7648 | fprintf_filtered (file, _("\ |
| 7649 | The current ARM floating point model is \"%s\".\n"), |
| 7650 | fp_model_strings[arm_fp_model]); |
| 7651 | } |
| 7652 | |
| 7653 | static void |
| 7654 | arm_set_abi (char *args, int from_tty, |
| 7655 | struct cmd_list_element *c) |
| 7656 | { |
| 7657 | enum arm_abi_kind arm_abi; |
| 7658 | |
| 7659 | for (arm_abi = ARM_ABI_AUTO; arm_abi != ARM_ABI_LAST; arm_abi++) |
| 7660 | if (strcmp (arm_abi_string, arm_abi_strings[arm_abi]) == 0) |
| 7661 | { |
| 7662 | arm_abi_global = arm_abi; |
| 7663 | break; |
| 7664 | } |
| 7665 | |
| 7666 | if (arm_abi == ARM_ABI_LAST) |
| 7667 | internal_error (__FILE__, __LINE__, _("Invalid ABI accepted: %s."), |
| 7668 | arm_abi_string); |
| 7669 | |
| 7670 | arm_update_current_architecture (); |
| 7671 | } |
| 7672 | |
| 7673 | static void |
| 7674 | arm_show_abi (struct ui_file *file, int from_tty, |
| 7675 | struct cmd_list_element *c, const char *value) |
| 7676 | { |
| 7677 | struct gdbarch_tdep *tdep = gdbarch_tdep (target_gdbarch); |
| 7678 | |
| 7679 | if (arm_abi_global == ARM_ABI_AUTO |
| 7680 | && gdbarch_bfd_arch_info (target_gdbarch)->arch == bfd_arch_arm) |
| 7681 | fprintf_filtered (file, _("\ |
| 7682 | The current ARM ABI is \"auto\" (currently \"%s\").\n"), |
| 7683 | arm_abi_strings[tdep->arm_abi]); |
| 7684 | else |
| 7685 | fprintf_filtered (file, _("The current ARM ABI is \"%s\".\n"), |
| 7686 | arm_abi_string); |
| 7687 | } |
| 7688 | |
| 7689 | static void |
| 7690 | arm_show_fallback_mode (struct ui_file *file, int from_tty, |
| 7691 | struct cmd_list_element *c, const char *value) |
| 7692 | { |
| 7693 | struct gdbarch_tdep *tdep = gdbarch_tdep (target_gdbarch); |
| 7694 | |
| 7695 | fprintf_filtered (file, |
| 7696 | _("The current execution mode assumed " |
| 7697 | "(when symbols are unavailable) is \"%s\".\n"), |
| 7698 | arm_fallback_mode_string); |
| 7699 | } |
| 7700 | |
| 7701 | static void |
| 7702 | arm_show_force_mode (struct ui_file *file, int from_tty, |
| 7703 | struct cmd_list_element *c, const char *value) |
| 7704 | { |
| 7705 | struct gdbarch_tdep *tdep = gdbarch_tdep (target_gdbarch); |
| 7706 | |
| 7707 | fprintf_filtered (file, |
| 7708 | _("The current execution mode assumed " |
| 7709 | "(even when symbols are available) is \"%s\".\n"), |
| 7710 | arm_force_mode_string); |
| 7711 | } |
| 7712 | |
| 7713 | /* If the user changes the register disassembly style used for info |
| 7714 | register and other commands, we have to also switch the style used |
| 7715 | in opcodes for disassembly output. This function is run in the "set |
| 7716 | arm disassembly" command, and does that. */ |
| 7717 | |
| 7718 | static void |
| 7719 | set_disassembly_style_sfunc (char *args, int from_tty, |
| 7720 | struct cmd_list_element *c) |
| 7721 | { |
| 7722 | set_disassembly_style (); |
| 7723 | } |
| 7724 | \f |
| 7725 | /* Return the ARM register name corresponding to register I. */ |
| 7726 | static const char * |
| 7727 | arm_register_name (struct gdbarch *gdbarch, int i) |
| 7728 | { |
| 7729 | const int num_regs = gdbarch_num_regs (gdbarch); |
| 7730 | |
| 7731 | if (gdbarch_tdep (gdbarch)->have_vfp_pseudos |
| 7732 | && i >= num_regs && i < num_regs + 32) |
| 7733 | { |
| 7734 | static const char *const vfp_pseudo_names[] = { |
| 7735 | "s0", "s1", "s2", "s3", "s4", "s5", "s6", "s7", |
| 7736 | "s8", "s9", "s10", "s11", "s12", "s13", "s14", "s15", |
| 7737 | "s16", "s17", "s18", "s19", "s20", "s21", "s22", "s23", |
| 7738 | "s24", "s25", "s26", "s27", "s28", "s29", "s30", "s31", |
| 7739 | }; |
| 7740 | |
| 7741 | return vfp_pseudo_names[i - num_regs]; |
| 7742 | } |
| 7743 | |
| 7744 | if (gdbarch_tdep (gdbarch)->have_neon_pseudos |
| 7745 | && i >= num_regs + 32 && i < num_regs + 32 + 16) |
| 7746 | { |
| 7747 | static const char *const neon_pseudo_names[] = { |
| 7748 | "q0", "q1", "q2", "q3", "q4", "q5", "q6", "q7", |
| 7749 | "q8", "q9", "q10", "q11", "q12", "q13", "q14", "q15", |
| 7750 | }; |
| 7751 | |
| 7752 | return neon_pseudo_names[i - num_regs - 32]; |
| 7753 | } |
| 7754 | |
| 7755 | if (i >= ARRAY_SIZE (arm_register_names)) |
| 7756 | /* These registers are only supported on targets which supply |
| 7757 | an XML description. */ |
| 7758 | return ""; |
| 7759 | |
| 7760 | return arm_register_names[i]; |
| 7761 | } |
| 7762 | |
| 7763 | static void |
| 7764 | set_disassembly_style (void) |
| 7765 | { |
| 7766 | int current; |
| 7767 | |
| 7768 | /* Find the style that the user wants. */ |
| 7769 | for (current = 0; current < num_disassembly_options; current++) |
| 7770 | if (disassembly_style == valid_disassembly_styles[current]) |
| 7771 | break; |
| 7772 | gdb_assert (current < num_disassembly_options); |
| 7773 | |
| 7774 | /* Synchronize the disassembler. */ |
| 7775 | set_arm_regname_option (current); |
| 7776 | } |
| 7777 | |
| 7778 | /* Test whether the coff symbol specific value corresponds to a Thumb |
| 7779 | function. */ |
| 7780 | |
| 7781 | static int |
| 7782 | coff_sym_is_thumb (int val) |
| 7783 | { |
| 7784 | return (val == C_THUMBEXT |
| 7785 | || val == C_THUMBSTAT |
| 7786 | || val == C_THUMBEXTFUNC |
| 7787 | || val == C_THUMBSTATFUNC |
| 7788 | || val == C_THUMBLABEL); |
| 7789 | } |
| 7790 | |
| 7791 | /* arm_coff_make_msymbol_special() |
| 7792 | arm_elf_make_msymbol_special() |
| 7793 | |
| 7794 | These functions test whether the COFF or ELF symbol corresponds to |
| 7795 | an address in thumb code, and set a "special" bit in a minimal |
| 7796 | symbol to indicate that it does. */ |
| 7797 | |
| 7798 | static void |
| 7799 | arm_elf_make_msymbol_special(asymbol *sym, struct minimal_symbol *msym) |
| 7800 | { |
| 7801 | /* Thumb symbols are of type STT_LOPROC, (synonymous with |
| 7802 | STT_ARM_TFUNC). */ |
| 7803 | if (ELF_ST_TYPE (((elf_symbol_type *)sym)->internal_elf_sym.st_info) |
| 7804 | == STT_LOPROC) |
| 7805 | MSYMBOL_SET_SPECIAL (msym); |
| 7806 | } |
| 7807 | |
| 7808 | static void |
| 7809 | arm_coff_make_msymbol_special(int val, struct minimal_symbol *msym) |
| 7810 | { |
| 7811 | if (coff_sym_is_thumb (val)) |
| 7812 | MSYMBOL_SET_SPECIAL (msym); |
| 7813 | } |
| 7814 | |
| 7815 | static void |
| 7816 | arm_objfile_data_free (struct objfile *objfile, void *arg) |
| 7817 | { |
| 7818 | struct arm_per_objfile *data = arg; |
| 7819 | unsigned int i; |
| 7820 | |
| 7821 | for (i = 0; i < objfile->obfd->section_count; i++) |
| 7822 | VEC_free (arm_mapping_symbol_s, data->section_maps[i]); |
| 7823 | } |
| 7824 | |
| 7825 | static void |
| 7826 | arm_record_special_symbol (struct gdbarch *gdbarch, struct objfile *objfile, |
| 7827 | asymbol *sym) |
| 7828 | { |
| 7829 | const char *name = bfd_asymbol_name (sym); |
| 7830 | struct arm_per_objfile *data; |
| 7831 | VEC(arm_mapping_symbol_s) **map_p; |
| 7832 | struct arm_mapping_symbol new_map_sym; |
| 7833 | |
| 7834 | gdb_assert (name[0] == '$'); |
| 7835 | if (name[1] != 'a' && name[1] != 't' && name[1] != 'd') |
| 7836 | return; |
| 7837 | |
| 7838 | data = objfile_data (objfile, arm_objfile_data_key); |
| 7839 | if (data == NULL) |
| 7840 | { |
| 7841 | data = OBSTACK_ZALLOC (&objfile->objfile_obstack, |
| 7842 | struct arm_per_objfile); |
| 7843 | set_objfile_data (objfile, arm_objfile_data_key, data); |
| 7844 | data->section_maps = OBSTACK_CALLOC (&objfile->objfile_obstack, |
| 7845 | objfile->obfd->section_count, |
| 7846 | VEC(arm_mapping_symbol_s) *); |
| 7847 | } |
| 7848 | map_p = &data->section_maps[bfd_get_section (sym)->index]; |
| 7849 | |
| 7850 | new_map_sym.value = sym->value; |
| 7851 | new_map_sym.type = name[1]; |
| 7852 | |
| 7853 | /* Assume that most mapping symbols appear in order of increasing |
| 7854 | value. If they were randomly distributed, it would be faster to |
| 7855 | always push here and then sort at first use. */ |
| 7856 | if (!VEC_empty (arm_mapping_symbol_s, *map_p)) |
| 7857 | { |
| 7858 | struct arm_mapping_symbol *prev_map_sym; |
| 7859 | |
| 7860 | prev_map_sym = VEC_last (arm_mapping_symbol_s, *map_p); |
| 7861 | if (prev_map_sym->value >= sym->value) |
| 7862 | { |
| 7863 | unsigned int idx; |
| 7864 | idx = VEC_lower_bound (arm_mapping_symbol_s, *map_p, &new_map_sym, |
| 7865 | arm_compare_mapping_symbols); |
| 7866 | VEC_safe_insert (arm_mapping_symbol_s, *map_p, idx, &new_map_sym); |
| 7867 | return; |
| 7868 | } |
| 7869 | } |
| 7870 | |
| 7871 | VEC_safe_push (arm_mapping_symbol_s, *map_p, &new_map_sym); |
| 7872 | } |
| 7873 | |
| 7874 | static void |
| 7875 | arm_write_pc (struct regcache *regcache, CORE_ADDR pc) |
| 7876 | { |
| 7877 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 7878 | regcache_cooked_write_unsigned (regcache, ARM_PC_REGNUM, pc); |
| 7879 | |
| 7880 | /* If necessary, set the T bit. */ |
| 7881 | if (arm_apcs_32) |
| 7882 | { |
| 7883 | ULONGEST val, t_bit; |
| 7884 | regcache_cooked_read_unsigned (regcache, ARM_PS_REGNUM, &val); |
| 7885 | t_bit = arm_psr_thumb_bit (gdbarch); |
| 7886 | if (arm_pc_is_thumb (gdbarch, pc)) |
| 7887 | regcache_cooked_write_unsigned (regcache, ARM_PS_REGNUM, |
| 7888 | val | t_bit); |
| 7889 | else |
| 7890 | regcache_cooked_write_unsigned (regcache, ARM_PS_REGNUM, |
| 7891 | val & ~t_bit); |
| 7892 | } |
| 7893 | } |
| 7894 | |
| 7895 | /* Read the contents of a NEON quad register, by reading from two |
| 7896 | double registers. This is used to implement the quad pseudo |
| 7897 | registers, and for argument passing in case the quad registers are |
| 7898 | missing; vectors are passed in quad registers when using the VFP |
| 7899 | ABI, even if a NEON unit is not present. REGNUM is the index of |
| 7900 | the quad register, in [0, 15]. */ |
| 7901 | |
| 7902 | static void |
| 7903 | arm_neon_quad_read (struct gdbarch *gdbarch, struct regcache *regcache, |
| 7904 | int regnum, gdb_byte *buf) |
| 7905 | { |
| 7906 | char name_buf[4]; |
| 7907 | gdb_byte reg_buf[8]; |
| 7908 | int offset, double_regnum; |
| 7909 | |
| 7910 | sprintf (name_buf, "d%d", regnum << 1); |
| 7911 | double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf, |
| 7912 | strlen (name_buf)); |
| 7913 | |
| 7914 | /* d0 is always the least significant half of q0. */ |
| 7915 | if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG) |
| 7916 | offset = 8; |
| 7917 | else |
| 7918 | offset = 0; |
| 7919 | |
| 7920 | regcache_raw_read (regcache, double_regnum, reg_buf); |
| 7921 | memcpy (buf + offset, reg_buf, 8); |
| 7922 | |
| 7923 | offset = 8 - offset; |
| 7924 | regcache_raw_read (regcache, double_regnum + 1, reg_buf); |
| 7925 | memcpy (buf + offset, reg_buf, 8); |
| 7926 | } |
| 7927 | |
| 7928 | static void |
| 7929 | arm_pseudo_read (struct gdbarch *gdbarch, struct regcache *regcache, |
| 7930 | int regnum, gdb_byte *buf) |
| 7931 | { |
| 7932 | const int num_regs = gdbarch_num_regs (gdbarch); |
| 7933 | char name_buf[4]; |
| 7934 | gdb_byte reg_buf[8]; |
| 7935 | int offset, double_regnum; |
| 7936 | |
| 7937 | gdb_assert (regnum >= num_regs); |
| 7938 | regnum -= num_regs; |
| 7939 | |
| 7940 | if (gdbarch_tdep (gdbarch)->have_neon_pseudos && regnum >= 32 && regnum < 48) |
| 7941 | /* Quad-precision register. */ |
| 7942 | arm_neon_quad_read (gdbarch, regcache, regnum - 32, buf); |
| 7943 | else |
| 7944 | { |
| 7945 | /* Single-precision register. */ |
| 7946 | gdb_assert (regnum < 32); |
| 7947 | |
| 7948 | /* s0 is always the least significant half of d0. */ |
| 7949 | if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG) |
| 7950 | offset = (regnum & 1) ? 0 : 4; |
| 7951 | else |
| 7952 | offset = (regnum & 1) ? 4 : 0; |
| 7953 | |
| 7954 | sprintf (name_buf, "d%d", regnum >> 1); |
| 7955 | double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf, |
| 7956 | strlen (name_buf)); |
| 7957 | |
| 7958 | regcache_raw_read (regcache, double_regnum, reg_buf); |
| 7959 | memcpy (buf, reg_buf + offset, 4); |
| 7960 | } |
| 7961 | } |
| 7962 | |
| 7963 | /* Store the contents of BUF to a NEON quad register, by writing to |
| 7964 | two double registers. This is used to implement the quad pseudo |
| 7965 | registers, and for argument passing in case the quad registers are |
| 7966 | missing; vectors are passed in quad registers when using the VFP |
| 7967 | ABI, even if a NEON unit is not present. REGNUM is the index |
| 7968 | of the quad register, in [0, 15]. */ |
| 7969 | |
| 7970 | static void |
| 7971 | arm_neon_quad_write (struct gdbarch *gdbarch, struct regcache *regcache, |
| 7972 | int regnum, const gdb_byte *buf) |
| 7973 | { |
| 7974 | char name_buf[4]; |
| 7975 | gdb_byte reg_buf[8]; |
| 7976 | int offset, double_regnum; |
| 7977 | |
| 7978 | sprintf (name_buf, "d%d", regnum << 1); |
| 7979 | double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf, |
| 7980 | strlen (name_buf)); |
| 7981 | |
| 7982 | /* d0 is always the least significant half of q0. */ |
| 7983 | if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG) |
| 7984 | offset = 8; |
| 7985 | else |
| 7986 | offset = 0; |
| 7987 | |
| 7988 | regcache_raw_write (regcache, double_regnum, buf + offset); |
| 7989 | offset = 8 - offset; |
| 7990 | regcache_raw_write (regcache, double_regnum + 1, buf + offset); |
| 7991 | } |
| 7992 | |
| 7993 | static void |
| 7994 | arm_pseudo_write (struct gdbarch *gdbarch, struct regcache *regcache, |
| 7995 | int regnum, const gdb_byte *buf) |
| 7996 | { |
| 7997 | const int num_regs = gdbarch_num_regs (gdbarch); |
| 7998 | char name_buf[4]; |
| 7999 | gdb_byte reg_buf[8]; |
| 8000 | int offset, double_regnum; |
| 8001 | |
| 8002 | gdb_assert (regnum >= num_regs); |
| 8003 | regnum -= num_regs; |
| 8004 | |
| 8005 | if (gdbarch_tdep (gdbarch)->have_neon_pseudos && regnum >= 32 && regnum < 48) |
| 8006 | /* Quad-precision register. */ |
| 8007 | arm_neon_quad_write (gdbarch, regcache, regnum - 32, buf); |
| 8008 | else |
| 8009 | { |
| 8010 | /* Single-precision register. */ |
| 8011 | gdb_assert (regnum < 32); |
| 8012 | |
| 8013 | /* s0 is always the least significant half of d0. */ |
| 8014 | if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG) |
| 8015 | offset = (regnum & 1) ? 0 : 4; |
| 8016 | else |
| 8017 | offset = (regnum & 1) ? 4 : 0; |
| 8018 | |
| 8019 | sprintf (name_buf, "d%d", regnum >> 1); |
| 8020 | double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf, |
| 8021 | strlen (name_buf)); |
| 8022 | |
| 8023 | regcache_raw_read (regcache, double_regnum, reg_buf); |
| 8024 | memcpy (reg_buf + offset, buf, 4); |
| 8025 | regcache_raw_write (regcache, double_regnum, reg_buf); |
| 8026 | } |
| 8027 | } |
| 8028 | |
| 8029 | static struct value * |
| 8030 | value_of_arm_user_reg (struct frame_info *frame, const void *baton) |
| 8031 | { |
| 8032 | const int *reg_p = baton; |
| 8033 | return value_of_register (*reg_p, frame); |
| 8034 | } |
| 8035 | \f |
| 8036 | static enum gdb_osabi |
| 8037 | arm_elf_osabi_sniffer (bfd *abfd) |
| 8038 | { |
| 8039 | unsigned int elfosabi; |
| 8040 | enum gdb_osabi osabi = GDB_OSABI_UNKNOWN; |
| 8041 | |
| 8042 | elfosabi = elf_elfheader (abfd)->e_ident[EI_OSABI]; |
| 8043 | |
| 8044 | if (elfosabi == ELFOSABI_ARM) |
| 8045 | /* GNU tools use this value. Check note sections in this case, |
| 8046 | as well. */ |
| 8047 | bfd_map_over_sections (abfd, |
| 8048 | generic_elf_osabi_sniff_abi_tag_sections, |
| 8049 | &osabi); |
| 8050 | |
| 8051 | /* Anything else will be handled by the generic ELF sniffer. */ |
| 8052 | return osabi; |
| 8053 | } |
| 8054 | |
| 8055 | static int |
| 8056 | arm_register_reggroup_p (struct gdbarch *gdbarch, int regnum, |
| 8057 | struct reggroup *group) |
| 8058 | { |
| 8059 | /* FPS register's type is INT, but belongs to float_reggroup. Beside |
| 8060 | this, FPS register belongs to save_regroup, restore_reggroup, and |
| 8061 | all_reggroup, of course. */ |
| 8062 | if (regnum == ARM_FPS_REGNUM) |
| 8063 | return (group == float_reggroup |
| 8064 | || group == save_reggroup |
| 8065 | || group == restore_reggroup |
| 8066 | || group == all_reggroup); |
| 8067 | else |
| 8068 | return default_register_reggroup_p (gdbarch, regnum, group); |
| 8069 | } |
| 8070 | |
| 8071 | \f |
| 8072 | /* Initialize the current architecture based on INFO. If possible, |
| 8073 | re-use an architecture from ARCHES, which is a list of |
| 8074 | architectures already created during this debugging session. |
| 8075 | |
| 8076 | Called e.g. at program startup, when reading a core file, and when |
| 8077 | reading a binary file. */ |
| 8078 | |
| 8079 | static struct gdbarch * |
| 8080 | arm_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) |
| 8081 | { |
| 8082 | struct gdbarch_tdep *tdep; |
| 8083 | struct gdbarch *gdbarch; |
| 8084 | struct gdbarch_list *best_arch; |
| 8085 | enum arm_abi_kind arm_abi = arm_abi_global; |
| 8086 | enum arm_float_model fp_model = arm_fp_model; |
| 8087 | struct tdesc_arch_data *tdesc_data = NULL; |
| 8088 | int i, is_m = 0; |
| 8089 | int have_vfp_registers = 0, have_vfp_pseudos = 0, have_neon_pseudos = 0; |
| 8090 | int have_neon = 0; |
| 8091 | int have_fpa_registers = 1; |
| 8092 | const struct target_desc *tdesc = info.target_desc; |
| 8093 | |
| 8094 | /* If we have an object to base this architecture on, try to determine |
| 8095 | its ABI. */ |
| 8096 | |
| 8097 | if (arm_abi == ARM_ABI_AUTO && info.abfd != NULL) |
| 8098 | { |
| 8099 | int ei_osabi, e_flags; |
| 8100 | |
| 8101 | switch (bfd_get_flavour (info.abfd)) |
| 8102 | { |
| 8103 | case bfd_target_aout_flavour: |
| 8104 | /* Assume it's an old APCS-style ABI. */ |
| 8105 | arm_abi = ARM_ABI_APCS; |
| 8106 | break; |
| 8107 | |
| 8108 | case bfd_target_coff_flavour: |
| 8109 | /* Assume it's an old APCS-style ABI. */ |
| 8110 | /* XXX WinCE? */ |
| 8111 | arm_abi = ARM_ABI_APCS; |
| 8112 | break; |
| 8113 | |
| 8114 | case bfd_target_elf_flavour: |
| 8115 | ei_osabi = elf_elfheader (info.abfd)->e_ident[EI_OSABI]; |
| 8116 | e_flags = elf_elfheader (info.abfd)->e_flags; |
| 8117 | |
| 8118 | if (ei_osabi == ELFOSABI_ARM) |
| 8119 | { |
| 8120 | /* GNU tools used to use this value, but do not for EABI |
| 8121 | objects. There's nowhere to tag an EABI version |
| 8122 | anyway, so assume APCS. */ |
| 8123 | arm_abi = ARM_ABI_APCS; |
| 8124 | } |
| 8125 | else if (ei_osabi == ELFOSABI_NONE) |
| 8126 | { |
| 8127 | int eabi_ver = EF_ARM_EABI_VERSION (e_flags); |
| 8128 | int attr_arch, attr_profile; |
| 8129 | |
| 8130 | switch (eabi_ver) |
| 8131 | { |
| 8132 | case EF_ARM_EABI_UNKNOWN: |
| 8133 | /* Assume GNU tools. */ |
| 8134 | arm_abi = ARM_ABI_APCS; |
| 8135 | break; |
| 8136 | |
| 8137 | case EF_ARM_EABI_VER4: |
| 8138 | case EF_ARM_EABI_VER5: |
| 8139 | arm_abi = ARM_ABI_AAPCS; |
| 8140 | /* EABI binaries default to VFP float ordering. |
| 8141 | They may also contain build attributes that can |
| 8142 | be used to identify if the VFP argument-passing |
| 8143 | ABI is in use. */ |
| 8144 | if (fp_model == ARM_FLOAT_AUTO) |
| 8145 | { |
| 8146 | #ifdef HAVE_ELF |
| 8147 | switch (bfd_elf_get_obj_attr_int (info.abfd, |
| 8148 | OBJ_ATTR_PROC, |
| 8149 | Tag_ABI_VFP_args)) |
| 8150 | { |
| 8151 | case 0: |
| 8152 | /* "The user intended FP parameter/result |
| 8153 | passing to conform to AAPCS, base |
| 8154 | variant". */ |
| 8155 | fp_model = ARM_FLOAT_SOFT_VFP; |
| 8156 | break; |
| 8157 | case 1: |
| 8158 | /* "The user intended FP parameter/result |
| 8159 | passing to conform to AAPCS, VFP |
| 8160 | variant". */ |
| 8161 | fp_model = ARM_FLOAT_VFP; |
| 8162 | break; |
| 8163 | case 2: |
| 8164 | /* "The user intended FP parameter/result |
| 8165 | passing to conform to tool chain-specific |
| 8166 | conventions" - we don't know any such |
| 8167 | conventions, so leave it as "auto". */ |
| 8168 | break; |
| 8169 | default: |
| 8170 | /* Attribute value not mentioned in the |
| 8171 | October 2008 ABI, so leave it as |
| 8172 | "auto". */ |
| 8173 | break; |
| 8174 | } |
| 8175 | #else |
| 8176 | fp_model = ARM_FLOAT_SOFT_VFP; |
| 8177 | #endif |
| 8178 | } |
| 8179 | break; |
| 8180 | |
| 8181 | default: |
| 8182 | /* Leave it as "auto". */ |
| 8183 | warning (_("unknown ARM EABI version 0x%x"), eabi_ver); |
| 8184 | break; |
| 8185 | } |
| 8186 | |
| 8187 | #ifdef HAVE_ELF |
| 8188 | /* Detect M-profile programs. This only works if the |
| 8189 | executable file includes build attributes; GCC does |
| 8190 | copy them to the executable, but e.g. RealView does |
| 8191 | not. */ |
| 8192 | attr_arch = bfd_elf_get_obj_attr_int (info.abfd, OBJ_ATTR_PROC, |
| 8193 | Tag_CPU_arch); |
| 8194 | attr_profile = bfd_elf_get_obj_attr_int (info.abfd, |
| 8195 | OBJ_ATTR_PROC, |
| 8196 | Tag_CPU_arch_profile); |
| 8197 | /* GCC specifies the profile for v6-M; RealView only |
| 8198 | specifies the profile for architectures starting with |
| 8199 | V7 (as opposed to architectures with a tag |
| 8200 | numerically greater than TAG_CPU_ARCH_V7). */ |
| 8201 | if (!tdesc_has_registers (tdesc) |
| 8202 | && (attr_arch == TAG_CPU_ARCH_V6_M |
| 8203 | || attr_arch == TAG_CPU_ARCH_V6S_M |
| 8204 | || attr_profile == 'M')) |
| 8205 | tdesc = tdesc_arm_with_m; |
| 8206 | #endif |
| 8207 | } |
| 8208 | |
| 8209 | if (fp_model == ARM_FLOAT_AUTO) |
| 8210 | { |
| 8211 | int e_flags = elf_elfheader (info.abfd)->e_flags; |
| 8212 | |
| 8213 | switch (e_flags & (EF_ARM_SOFT_FLOAT | EF_ARM_VFP_FLOAT)) |
| 8214 | { |
| 8215 | case 0: |
| 8216 | /* Leave it as "auto". Strictly speaking this case |
| 8217 | means FPA, but almost nobody uses that now, and |
| 8218 | many toolchains fail to set the appropriate bits |
| 8219 | for the floating-point model they use. */ |
| 8220 | break; |
| 8221 | case EF_ARM_SOFT_FLOAT: |
| 8222 | fp_model = ARM_FLOAT_SOFT_FPA; |
| 8223 | break; |
| 8224 | case EF_ARM_VFP_FLOAT: |
| 8225 | fp_model = ARM_FLOAT_VFP; |
| 8226 | break; |
| 8227 | case EF_ARM_SOFT_FLOAT | EF_ARM_VFP_FLOAT: |
| 8228 | fp_model = ARM_FLOAT_SOFT_VFP; |
| 8229 | break; |
| 8230 | } |
| 8231 | } |
| 8232 | |
| 8233 | if (e_flags & EF_ARM_BE8) |
| 8234 | info.byte_order_for_code = BFD_ENDIAN_LITTLE; |
| 8235 | |
| 8236 | break; |
| 8237 | |
| 8238 | default: |
| 8239 | /* Leave it as "auto". */ |
| 8240 | break; |
| 8241 | } |
| 8242 | } |
| 8243 | |
| 8244 | /* Check any target description for validity. */ |
| 8245 | if (tdesc_has_registers (tdesc)) |
| 8246 | { |
| 8247 | /* For most registers we require GDB's default names; but also allow |
| 8248 | the numeric names for sp / lr / pc, as a convenience. */ |
| 8249 | static const char *const arm_sp_names[] = { "r13", "sp", NULL }; |
| 8250 | static const char *const arm_lr_names[] = { "r14", "lr", NULL }; |
| 8251 | static const char *const arm_pc_names[] = { "r15", "pc", NULL }; |
| 8252 | |
| 8253 | const struct tdesc_feature *feature; |
| 8254 | int valid_p; |
| 8255 | |
| 8256 | feature = tdesc_find_feature (tdesc, |
| 8257 | "org.gnu.gdb.arm.core"); |
| 8258 | if (feature == NULL) |
| 8259 | { |
| 8260 | feature = tdesc_find_feature (tdesc, |
| 8261 | "org.gnu.gdb.arm.m-profile"); |
| 8262 | if (feature == NULL) |
| 8263 | return NULL; |
| 8264 | else |
| 8265 | is_m = 1; |
| 8266 | } |
| 8267 | |
| 8268 | tdesc_data = tdesc_data_alloc (); |
| 8269 | |
| 8270 | valid_p = 1; |
| 8271 | for (i = 0; i < ARM_SP_REGNUM; i++) |
| 8272 | valid_p &= tdesc_numbered_register (feature, tdesc_data, i, |
| 8273 | arm_register_names[i]); |
| 8274 | valid_p &= tdesc_numbered_register_choices (feature, tdesc_data, |
| 8275 | ARM_SP_REGNUM, |
| 8276 | arm_sp_names); |
| 8277 | valid_p &= tdesc_numbered_register_choices (feature, tdesc_data, |
| 8278 | ARM_LR_REGNUM, |
| 8279 | arm_lr_names); |
| 8280 | valid_p &= tdesc_numbered_register_choices (feature, tdesc_data, |
| 8281 | ARM_PC_REGNUM, |
| 8282 | arm_pc_names); |
| 8283 | if (is_m) |
| 8284 | valid_p &= tdesc_numbered_register (feature, tdesc_data, |
| 8285 | ARM_PS_REGNUM, "xpsr"); |
| 8286 | else |
| 8287 | valid_p &= tdesc_numbered_register (feature, tdesc_data, |
| 8288 | ARM_PS_REGNUM, "cpsr"); |
| 8289 | |
| 8290 | if (!valid_p) |
| 8291 | { |
| 8292 | tdesc_data_cleanup (tdesc_data); |
| 8293 | return NULL; |
| 8294 | } |
| 8295 | |
| 8296 | feature = tdesc_find_feature (tdesc, |
| 8297 | "org.gnu.gdb.arm.fpa"); |
| 8298 | if (feature != NULL) |
| 8299 | { |
| 8300 | valid_p = 1; |
| 8301 | for (i = ARM_F0_REGNUM; i <= ARM_FPS_REGNUM; i++) |
| 8302 | valid_p &= tdesc_numbered_register (feature, tdesc_data, i, |
| 8303 | arm_register_names[i]); |
| 8304 | if (!valid_p) |
| 8305 | { |
| 8306 | tdesc_data_cleanup (tdesc_data); |
| 8307 | return NULL; |
| 8308 | } |
| 8309 | } |
| 8310 | else |
| 8311 | have_fpa_registers = 0; |
| 8312 | |
| 8313 | feature = tdesc_find_feature (tdesc, |
| 8314 | "org.gnu.gdb.xscale.iwmmxt"); |
| 8315 | if (feature != NULL) |
| 8316 | { |
| 8317 | static const char *const iwmmxt_names[] = { |
| 8318 | "wR0", "wR1", "wR2", "wR3", "wR4", "wR5", "wR6", "wR7", |
| 8319 | "wR8", "wR9", "wR10", "wR11", "wR12", "wR13", "wR14", "wR15", |
| 8320 | "wCID", "wCon", "wCSSF", "wCASF", "", "", "", "", |
| 8321 | "wCGR0", "wCGR1", "wCGR2", "wCGR3", "", "", "", "", |
| 8322 | }; |
| 8323 | |
| 8324 | valid_p = 1; |
| 8325 | for (i = ARM_WR0_REGNUM; i <= ARM_WR15_REGNUM; i++) |
| 8326 | valid_p |
| 8327 | &= tdesc_numbered_register (feature, tdesc_data, i, |
| 8328 | iwmmxt_names[i - ARM_WR0_REGNUM]); |
| 8329 | |
| 8330 | /* Check for the control registers, but do not fail if they |
| 8331 | are missing. */ |
| 8332 | for (i = ARM_WC0_REGNUM; i <= ARM_WCASF_REGNUM; i++) |
| 8333 | tdesc_numbered_register (feature, tdesc_data, i, |
| 8334 | iwmmxt_names[i - ARM_WR0_REGNUM]); |
| 8335 | |
| 8336 | for (i = ARM_WCGR0_REGNUM; i <= ARM_WCGR3_REGNUM; i++) |
| 8337 | valid_p |
| 8338 | &= tdesc_numbered_register (feature, tdesc_data, i, |
| 8339 | iwmmxt_names[i - ARM_WR0_REGNUM]); |
| 8340 | |
| 8341 | if (!valid_p) |
| 8342 | { |
| 8343 | tdesc_data_cleanup (tdesc_data); |
| 8344 | return NULL; |
| 8345 | } |
| 8346 | } |
| 8347 | |
| 8348 | /* If we have a VFP unit, check whether the single precision registers |
| 8349 | are present. If not, then we will synthesize them as pseudo |
| 8350 | registers. */ |
| 8351 | feature = tdesc_find_feature (tdesc, |
| 8352 | "org.gnu.gdb.arm.vfp"); |
| 8353 | if (feature != NULL) |
| 8354 | { |
| 8355 | static const char *const vfp_double_names[] = { |
| 8356 | "d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7", |
| 8357 | "d8", "d9", "d10", "d11", "d12", "d13", "d14", "d15", |
| 8358 | "d16", "d17", "d18", "d19", "d20", "d21", "d22", "d23", |
| 8359 | "d24", "d25", "d26", "d27", "d28", "d29", "d30", "d31", |
| 8360 | }; |
| 8361 | |
| 8362 | /* Require the double precision registers. There must be either |
| 8363 | 16 or 32. */ |
| 8364 | valid_p = 1; |
| 8365 | for (i = 0; i < 32; i++) |
| 8366 | { |
| 8367 | valid_p &= tdesc_numbered_register (feature, tdesc_data, |
| 8368 | ARM_D0_REGNUM + i, |
| 8369 | vfp_double_names[i]); |
| 8370 | if (!valid_p) |
| 8371 | break; |
| 8372 | } |
| 8373 | |
| 8374 | if (!valid_p && i != 16) |
| 8375 | { |
| 8376 | tdesc_data_cleanup (tdesc_data); |
| 8377 | return NULL; |
| 8378 | } |
| 8379 | |
| 8380 | if (tdesc_unnumbered_register (feature, "s0") == 0) |
| 8381 | have_vfp_pseudos = 1; |
| 8382 | |
| 8383 | have_vfp_registers = 1; |
| 8384 | |
| 8385 | /* If we have VFP, also check for NEON. The architecture allows |
| 8386 | NEON without VFP (integer vector operations only), but GDB |
| 8387 | does not support that. */ |
| 8388 | feature = tdesc_find_feature (tdesc, |
| 8389 | "org.gnu.gdb.arm.neon"); |
| 8390 | if (feature != NULL) |
| 8391 | { |
| 8392 | /* NEON requires 32 double-precision registers. */ |
| 8393 | if (i != 32) |
| 8394 | { |
| 8395 | tdesc_data_cleanup (tdesc_data); |
| 8396 | return NULL; |
| 8397 | } |
| 8398 | |
| 8399 | /* If there are quad registers defined by the stub, use |
| 8400 | their type; otherwise (normally) provide them with |
| 8401 | the default type. */ |
| 8402 | if (tdesc_unnumbered_register (feature, "q0") == 0) |
| 8403 | have_neon_pseudos = 1; |
| 8404 | |
| 8405 | have_neon = 1; |
| 8406 | } |
| 8407 | } |
| 8408 | } |
| 8409 | |
| 8410 | /* If there is already a candidate, use it. */ |
| 8411 | for (best_arch = gdbarch_list_lookup_by_info (arches, &info); |
| 8412 | best_arch != NULL; |
| 8413 | best_arch = gdbarch_list_lookup_by_info (best_arch->next, &info)) |
| 8414 | { |
| 8415 | if (arm_abi != ARM_ABI_AUTO |
| 8416 | && arm_abi != gdbarch_tdep (best_arch->gdbarch)->arm_abi) |
| 8417 | continue; |
| 8418 | |
| 8419 | if (fp_model != ARM_FLOAT_AUTO |
| 8420 | && fp_model != gdbarch_tdep (best_arch->gdbarch)->fp_model) |
| 8421 | continue; |
| 8422 | |
| 8423 | /* There are various other properties in tdep that we do not |
| 8424 | need to check here: those derived from a target description, |
| 8425 | since gdbarches with a different target description are |
| 8426 | automatically disqualified. */ |
| 8427 | |
| 8428 | /* Do check is_m, though, since it might come from the binary. */ |
| 8429 | if (is_m != gdbarch_tdep (best_arch->gdbarch)->is_m) |
| 8430 | continue; |
| 8431 | |
| 8432 | /* Found a match. */ |
| 8433 | break; |
| 8434 | } |
| 8435 | |
| 8436 | if (best_arch != NULL) |
| 8437 | { |
| 8438 | if (tdesc_data != NULL) |
| 8439 | tdesc_data_cleanup (tdesc_data); |
| 8440 | return best_arch->gdbarch; |
| 8441 | } |
| 8442 | |
| 8443 | tdep = xcalloc (1, sizeof (struct gdbarch_tdep)); |
| 8444 | gdbarch = gdbarch_alloc (&info, tdep); |
| 8445 | |
| 8446 | /* Record additional information about the architecture we are defining. |
| 8447 | These are gdbarch discriminators, like the OSABI. */ |
| 8448 | tdep->arm_abi = arm_abi; |
| 8449 | tdep->fp_model = fp_model; |
| 8450 | tdep->is_m = is_m; |
| 8451 | tdep->have_fpa_registers = have_fpa_registers; |
| 8452 | tdep->have_vfp_registers = have_vfp_registers; |
| 8453 | tdep->have_vfp_pseudos = have_vfp_pseudos; |
| 8454 | tdep->have_neon_pseudos = have_neon_pseudos; |
| 8455 | tdep->have_neon = have_neon; |
| 8456 | |
| 8457 | /* Breakpoints. */ |
| 8458 | switch (info.byte_order_for_code) |
| 8459 | { |
| 8460 | case BFD_ENDIAN_BIG: |
| 8461 | tdep->arm_breakpoint = arm_default_arm_be_breakpoint; |
| 8462 | tdep->arm_breakpoint_size = sizeof (arm_default_arm_be_breakpoint); |
| 8463 | tdep->thumb_breakpoint = arm_default_thumb_be_breakpoint; |
| 8464 | tdep->thumb_breakpoint_size = sizeof (arm_default_thumb_be_breakpoint); |
| 8465 | |
| 8466 | break; |
| 8467 | |
| 8468 | case BFD_ENDIAN_LITTLE: |
| 8469 | tdep->arm_breakpoint = arm_default_arm_le_breakpoint; |
| 8470 | tdep->arm_breakpoint_size = sizeof (arm_default_arm_le_breakpoint); |
| 8471 | tdep->thumb_breakpoint = arm_default_thumb_le_breakpoint; |
| 8472 | tdep->thumb_breakpoint_size = sizeof (arm_default_thumb_le_breakpoint); |
| 8473 | |
| 8474 | break; |
| 8475 | |
| 8476 | default: |
| 8477 | internal_error (__FILE__, __LINE__, |
| 8478 | _("arm_gdbarch_init: bad byte order for float format")); |
| 8479 | } |
| 8480 | |
| 8481 | /* On ARM targets char defaults to unsigned. */ |
| 8482 | set_gdbarch_char_signed (gdbarch, 0); |
| 8483 | |
| 8484 | /* Note: for displaced stepping, this includes the breakpoint, and one word |
| 8485 | of additional scratch space. This setting isn't used for anything beside |
| 8486 | displaced stepping at present. */ |
| 8487 | set_gdbarch_max_insn_length (gdbarch, 4 * DISPLACED_MODIFIED_INSNS); |
| 8488 | |
| 8489 | /* This should be low enough for everything. */ |
| 8490 | tdep->lowest_pc = 0x20; |
| 8491 | tdep->jb_pc = -1; /* Longjump support not enabled by default. */ |
| 8492 | |
| 8493 | /* The default, for both APCS and AAPCS, is to return small |
| 8494 | structures in registers. */ |
| 8495 | tdep->struct_return = reg_struct_return; |
| 8496 | |
| 8497 | set_gdbarch_push_dummy_call (gdbarch, arm_push_dummy_call); |
| 8498 | set_gdbarch_frame_align (gdbarch, arm_frame_align); |
| 8499 | |
| 8500 | set_gdbarch_write_pc (gdbarch, arm_write_pc); |
| 8501 | |
| 8502 | /* Frame handling. */ |
| 8503 | set_gdbarch_dummy_id (gdbarch, arm_dummy_id); |
| 8504 | set_gdbarch_unwind_pc (gdbarch, arm_unwind_pc); |
| 8505 | set_gdbarch_unwind_sp (gdbarch, arm_unwind_sp); |
| 8506 | |
| 8507 | frame_base_set_default (gdbarch, &arm_normal_base); |
| 8508 | |
| 8509 | /* Address manipulation. */ |
| 8510 | set_gdbarch_smash_text_address (gdbarch, arm_smash_text_address); |
| 8511 | set_gdbarch_addr_bits_remove (gdbarch, arm_addr_bits_remove); |
| 8512 | |
| 8513 | /* Advance PC across function entry code. */ |
| 8514 | set_gdbarch_skip_prologue (gdbarch, arm_skip_prologue); |
| 8515 | |
| 8516 | /* Detect whether PC is in function epilogue. */ |
| 8517 | set_gdbarch_in_function_epilogue_p (gdbarch, arm_in_function_epilogue_p); |
| 8518 | |
| 8519 | /* Skip trampolines. */ |
| 8520 | set_gdbarch_skip_trampoline_code (gdbarch, arm_skip_stub); |
| 8521 | |
| 8522 | /* The stack grows downward. */ |
| 8523 | set_gdbarch_inner_than (gdbarch, core_addr_lessthan); |
| 8524 | |
| 8525 | /* Breakpoint manipulation. */ |
| 8526 | set_gdbarch_breakpoint_from_pc (gdbarch, arm_breakpoint_from_pc); |
| 8527 | set_gdbarch_remote_breakpoint_from_pc (gdbarch, |
| 8528 | arm_remote_breakpoint_from_pc); |
| 8529 | |
| 8530 | /* Information about registers, etc. */ |
| 8531 | set_gdbarch_sp_regnum (gdbarch, ARM_SP_REGNUM); |
| 8532 | set_gdbarch_pc_regnum (gdbarch, ARM_PC_REGNUM); |
| 8533 | set_gdbarch_num_regs (gdbarch, ARM_NUM_REGS); |
| 8534 | set_gdbarch_register_type (gdbarch, arm_register_type); |
| 8535 | set_gdbarch_register_reggroup_p (gdbarch, arm_register_reggroup_p); |
| 8536 | |
| 8537 | /* This "info float" is FPA-specific. Use the generic version if we |
| 8538 | do not have FPA. */ |
| 8539 | if (gdbarch_tdep (gdbarch)->have_fpa_registers) |
| 8540 | set_gdbarch_print_float_info (gdbarch, arm_print_float_info); |
| 8541 | |
| 8542 | /* Internal <-> external register number maps. */ |
| 8543 | set_gdbarch_dwarf2_reg_to_regnum (gdbarch, arm_dwarf_reg_to_regnum); |
| 8544 | set_gdbarch_register_sim_regno (gdbarch, arm_register_sim_regno); |
| 8545 | |
| 8546 | set_gdbarch_register_name (gdbarch, arm_register_name); |
| 8547 | |
| 8548 | /* Returning results. */ |
| 8549 | set_gdbarch_return_value (gdbarch, arm_return_value); |
| 8550 | |
| 8551 | /* Disassembly. */ |
| 8552 | set_gdbarch_print_insn (gdbarch, gdb_print_insn_arm); |
| 8553 | |
| 8554 | /* Minsymbol frobbing. */ |
| 8555 | set_gdbarch_elf_make_msymbol_special (gdbarch, arm_elf_make_msymbol_special); |
| 8556 | set_gdbarch_coff_make_msymbol_special (gdbarch, |
| 8557 | arm_coff_make_msymbol_special); |
| 8558 | set_gdbarch_record_special_symbol (gdbarch, arm_record_special_symbol); |
| 8559 | |
| 8560 | /* Thumb-2 IT block support. */ |
| 8561 | set_gdbarch_adjust_breakpoint_address (gdbarch, |
| 8562 | arm_adjust_breakpoint_address); |
| 8563 | |
| 8564 | /* Virtual tables. */ |
| 8565 | set_gdbarch_vbit_in_delta (gdbarch, 1); |
| 8566 | |
| 8567 | /* Hook in the ABI-specific overrides, if they have been registered. */ |
| 8568 | gdbarch_init_osabi (info, gdbarch); |
| 8569 | |
| 8570 | dwarf2_frame_set_init_reg (gdbarch, arm_dwarf2_frame_init_reg); |
| 8571 | |
| 8572 | /* Add some default predicates. */ |
| 8573 | frame_unwind_append_unwinder (gdbarch, &arm_stub_unwind); |
| 8574 | dwarf2_append_unwinders (gdbarch); |
| 8575 | frame_unwind_append_unwinder (gdbarch, &arm_exidx_unwind); |
| 8576 | frame_unwind_append_unwinder (gdbarch, &arm_prologue_unwind); |
| 8577 | |
| 8578 | /* Now we have tuned the configuration, set a few final things, |
| 8579 | based on what the OS ABI has told us. */ |
| 8580 | |
| 8581 | /* If the ABI is not otherwise marked, assume the old GNU APCS. EABI |
| 8582 | binaries are always marked. */ |
| 8583 | if (tdep->arm_abi == ARM_ABI_AUTO) |
| 8584 | tdep->arm_abi = ARM_ABI_APCS; |
| 8585 | |
| 8586 | /* Watchpoints are not steppable. */ |
| 8587 | set_gdbarch_have_nonsteppable_watchpoint (gdbarch, 1); |
| 8588 | |
| 8589 | /* We used to default to FPA for generic ARM, but almost nobody |
| 8590 | uses that now, and we now provide a way for the user to force |
| 8591 | the model. So default to the most useful variant. */ |
| 8592 | if (tdep->fp_model == ARM_FLOAT_AUTO) |
| 8593 | tdep->fp_model = ARM_FLOAT_SOFT_FPA; |
| 8594 | |
| 8595 | if (tdep->jb_pc >= 0) |
| 8596 | set_gdbarch_get_longjmp_target (gdbarch, arm_get_longjmp_target); |
| 8597 | |
| 8598 | /* Floating point sizes and format. */ |
| 8599 | set_gdbarch_float_format (gdbarch, floatformats_ieee_single); |
| 8600 | if (tdep->fp_model == ARM_FLOAT_SOFT_FPA || tdep->fp_model == ARM_FLOAT_FPA) |
| 8601 | { |
| 8602 | set_gdbarch_double_format |
| 8603 | (gdbarch, floatformats_ieee_double_littlebyte_bigword); |
| 8604 | set_gdbarch_long_double_format |
| 8605 | (gdbarch, floatformats_ieee_double_littlebyte_bigword); |
| 8606 | } |
| 8607 | else |
| 8608 | { |
| 8609 | set_gdbarch_double_format (gdbarch, floatformats_ieee_double); |
| 8610 | set_gdbarch_long_double_format (gdbarch, floatformats_ieee_double); |
| 8611 | } |
| 8612 | |
| 8613 | if (have_vfp_pseudos) |
| 8614 | { |
| 8615 | /* NOTE: These are the only pseudo registers used by |
| 8616 | the ARM target at the moment. If more are added, a |
| 8617 | little more care in numbering will be needed. */ |
| 8618 | |
| 8619 | int num_pseudos = 32; |
| 8620 | if (have_neon_pseudos) |
| 8621 | num_pseudos += 16; |
| 8622 | set_gdbarch_num_pseudo_regs (gdbarch, num_pseudos); |
| 8623 | set_gdbarch_pseudo_register_read (gdbarch, arm_pseudo_read); |
| 8624 | set_gdbarch_pseudo_register_write (gdbarch, arm_pseudo_write); |
| 8625 | } |
| 8626 | |
| 8627 | if (tdesc_data) |
| 8628 | { |
| 8629 | set_tdesc_pseudo_register_name (gdbarch, arm_register_name); |
| 8630 | |
| 8631 | tdesc_use_registers (gdbarch, tdesc, tdesc_data); |
| 8632 | |
| 8633 | /* Override tdesc_register_type to adjust the types of VFP |
| 8634 | registers for NEON. */ |
| 8635 | set_gdbarch_register_type (gdbarch, arm_register_type); |
| 8636 | } |
| 8637 | |
| 8638 | /* Add standard register aliases. We add aliases even for those |
| 8639 | nanes which are used by the current architecture - it's simpler, |
| 8640 | and does no harm, since nothing ever lists user registers. */ |
| 8641 | for (i = 0; i < ARRAY_SIZE (arm_register_aliases); i++) |
| 8642 | user_reg_add (gdbarch, arm_register_aliases[i].name, |
| 8643 | value_of_arm_user_reg, &arm_register_aliases[i].regnum); |
| 8644 | |
| 8645 | return gdbarch; |
| 8646 | } |
| 8647 | |
| 8648 | static void |
| 8649 | arm_dump_tdep (struct gdbarch *gdbarch, struct ui_file *file) |
| 8650 | { |
| 8651 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 8652 | |
| 8653 | if (tdep == NULL) |
| 8654 | return; |
| 8655 | |
| 8656 | fprintf_unfiltered (file, _("arm_dump_tdep: Lowest pc = 0x%lx"), |
| 8657 | (unsigned long) tdep->lowest_pc); |
| 8658 | } |
| 8659 | |
| 8660 | extern initialize_file_ftype _initialize_arm_tdep; /* -Wmissing-prototypes */ |
| 8661 | |
| 8662 | void |
| 8663 | _initialize_arm_tdep (void) |
| 8664 | { |
| 8665 | struct ui_file *stb; |
| 8666 | long length; |
| 8667 | struct cmd_list_element *new_set, *new_show; |
| 8668 | const char *setname; |
| 8669 | const char *setdesc; |
| 8670 | const char *const *regnames; |
| 8671 | int numregs, i, j; |
| 8672 | static char *helptext; |
| 8673 | char regdesc[1024], *rdptr = regdesc; |
| 8674 | size_t rest = sizeof (regdesc); |
| 8675 | |
| 8676 | gdbarch_register (bfd_arch_arm, arm_gdbarch_init, arm_dump_tdep); |
| 8677 | |
| 8678 | arm_objfile_data_key |
| 8679 | = register_objfile_data_with_cleanup (NULL, arm_objfile_data_free); |
| 8680 | |
| 8681 | /* Add ourselves to objfile event chain. */ |
| 8682 | observer_attach_new_objfile (arm_exidx_new_objfile); |
| 8683 | arm_exidx_data_key |
| 8684 | = register_objfile_data_with_cleanup (NULL, arm_exidx_data_free); |
| 8685 | |
| 8686 | /* Register an ELF OS ABI sniffer for ARM binaries. */ |
| 8687 | gdbarch_register_osabi_sniffer (bfd_arch_arm, |
| 8688 | bfd_target_elf_flavour, |
| 8689 | arm_elf_osabi_sniffer); |
| 8690 | |
| 8691 | /* Initialize the standard target descriptions. */ |
| 8692 | initialize_tdesc_arm_with_m (); |
| 8693 | |
| 8694 | /* Get the number of possible sets of register names defined in opcodes. */ |
| 8695 | num_disassembly_options = get_arm_regname_num_options (); |
| 8696 | |
| 8697 | /* Add root prefix command for all "set arm"/"show arm" commands. */ |
| 8698 | add_prefix_cmd ("arm", no_class, set_arm_command, |
| 8699 | _("Various ARM-specific commands."), |
| 8700 | &setarmcmdlist, "set arm ", 0, &setlist); |
| 8701 | |
| 8702 | add_prefix_cmd ("arm", no_class, show_arm_command, |
| 8703 | _("Various ARM-specific commands."), |
| 8704 | &showarmcmdlist, "show arm ", 0, &showlist); |
| 8705 | |
| 8706 | /* Sync the opcode insn printer with our register viewer. */ |
| 8707 | parse_arm_disassembler_option ("reg-names-std"); |
| 8708 | |
| 8709 | /* Initialize the array that will be passed to |
| 8710 | add_setshow_enum_cmd(). */ |
| 8711 | valid_disassembly_styles |
| 8712 | = xmalloc ((num_disassembly_options + 1) * sizeof (char *)); |
| 8713 | for (i = 0; i < num_disassembly_options; i++) |
| 8714 | { |
| 8715 | numregs = get_arm_regnames (i, &setname, &setdesc, ®names); |
| 8716 | valid_disassembly_styles[i] = setname; |
| 8717 | length = snprintf (rdptr, rest, "%s - %s\n", setname, setdesc); |
| 8718 | rdptr += length; |
| 8719 | rest -= length; |
| 8720 | /* When we find the default names, tell the disassembler to use |
| 8721 | them. */ |
| 8722 | if (!strcmp (setname, "std")) |
| 8723 | { |
| 8724 | disassembly_style = setname; |
| 8725 | set_arm_regname_option (i); |
| 8726 | } |
| 8727 | } |
| 8728 | /* Mark the end of valid options. */ |
| 8729 | valid_disassembly_styles[num_disassembly_options] = NULL; |
| 8730 | |
| 8731 | /* Create the help text. */ |
| 8732 | stb = mem_fileopen (); |
| 8733 | fprintf_unfiltered (stb, "%s%s%s", |
| 8734 | _("The valid values are:\n"), |
| 8735 | regdesc, |
| 8736 | _("The default is \"std\".")); |
| 8737 | helptext = ui_file_xstrdup (stb, NULL); |
| 8738 | ui_file_delete (stb); |
| 8739 | |
| 8740 | add_setshow_enum_cmd("disassembler", no_class, |
| 8741 | valid_disassembly_styles, &disassembly_style, |
| 8742 | _("Set the disassembly style."), |
| 8743 | _("Show the disassembly style."), |
| 8744 | helptext, |
| 8745 | set_disassembly_style_sfunc, |
| 8746 | NULL, /* FIXME: i18n: The disassembly style is |
| 8747 | \"%s\". */ |
| 8748 | &setarmcmdlist, &showarmcmdlist); |
| 8749 | |
| 8750 | add_setshow_boolean_cmd ("apcs32", no_class, &arm_apcs_32, |
| 8751 | _("Set usage of ARM 32-bit mode."), |
| 8752 | _("Show usage of ARM 32-bit mode."), |
| 8753 | _("When off, a 26-bit PC will be used."), |
| 8754 | NULL, |
| 8755 | NULL, /* FIXME: i18n: Usage of ARM 32-bit |
| 8756 | mode is %s. */ |
| 8757 | &setarmcmdlist, &showarmcmdlist); |
| 8758 | |
| 8759 | /* Add a command to allow the user to force the FPU model. */ |
| 8760 | add_setshow_enum_cmd ("fpu", no_class, fp_model_strings, ¤t_fp_model, |
| 8761 | _("Set the floating point type."), |
| 8762 | _("Show the floating point type."), |
| 8763 | _("auto - Determine the FP typefrom the OS-ABI.\n\ |
| 8764 | softfpa - Software FP, mixed-endian doubles on little-endian ARMs.\n\ |
| 8765 | fpa - FPA co-processor (GCC compiled).\n\ |
| 8766 | softvfp - Software FP with pure-endian doubles.\n\ |
| 8767 | vfp - VFP co-processor."), |
| 8768 | set_fp_model_sfunc, show_fp_model, |
| 8769 | &setarmcmdlist, &showarmcmdlist); |
| 8770 | |
| 8771 | /* Add a command to allow the user to force the ABI. */ |
| 8772 | add_setshow_enum_cmd ("abi", class_support, arm_abi_strings, &arm_abi_string, |
| 8773 | _("Set the ABI."), |
| 8774 | _("Show the ABI."), |
| 8775 | NULL, arm_set_abi, arm_show_abi, |
| 8776 | &setarmcmdlist, &showarmcmdlist); |
| 8777 | |
| 8778 | /* Add two commands to allow the user to force the assumed |
| 8779 | execution mode. */ |
| 8780 | add_setshow_enum_cmd ("fallback-mode", class_support, |
| 8781 | arm_mode_strings, &arm_fallback_mode_string, |
| 8782 | _("Set the mode assumed when symbols are unavailable."), |
| 8783 | _("Show the mode assumed when symbols are unavailable."), |
| 8784 | NULL, NULL, arm_show_fallback_mode, |
| 8785 | &setarmcmdlist, &showarmcmdlist); |
| 8786 | add_setshow_enum_cmd ("force-mode", class_support, |
| 8787 | arm_mode_strings, &arm_force_mode_string, |
| 8788 | _("Set the mode assumed even when symbols are available."), |
| 8789 | _("Show the mode assumed even when symbols are available."), |
| 8790 | NULL, NULL, arm_show_force_mode, |
| 8791 | &setarmcmdlist, &showarmcmdlist); |
| 8792 | |
| 8793 | /* Debugging flag. */ |
| 8794 | add_setshow_boolean_cmd ("arm", class_maintenance, &arm_debug, |
| 8795 | _("Set ARM debugging."), |
| 8796 | _("Show ARM debugging."), |
| 8797 | _("When on, arm-specific debugging is enabled."), |
| 8798 | NULL, |
| 8799 | NULL, /* FIXME: i18n: "ARM debugging is %s. */ |
| 8800 | &setdebuglist, &showdebuglist); |
| 8801 | } |