| 1 | /* Target-dependent code for Motorola 68HC11 & 68HC12 |
| 2 | Copyright 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc. |
| 3 | Contributed by Stephane Carrez, stcarrez@nerim.fr |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 2 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program; if not, write to the Free Software |
| 19 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 20 | |
| 21 | |
| 22 | #include "defs.h" |
| 23 | #include "frame.h" |
| 24 | #include "symtab.h" |
| 25 | #include "gdbtypes.h" |
| 26 | #include "gdbcmd.h" |
| 27 | #include "gdbcore.h" |
| 28 | #include "gdb_string.h" |
| 29 | #include "value.h" |
| 30 | #include "inferior.h" |
| 31 | #include "dis-asm.h" |
| 32 | #include "symfile.h" |
| 33 | #include "objfiles.h" |
| 34 | #include "arch-utils.h" |
| 35 | #include "regcache.h" |
| 36 | |
| 37 | #include "target.h" |
| 38 | #include "opcode/m68hc11.h" |
| 39 | #include "elf/m68hc11.h" |
| 40 | #include "elf-bfd.h" |
| 41 | |
| 42 | /* Macros for setting and testing a bit in a minimal symbol. |
| 43 | For 68HC11/68HC12 we have two flags that tell which return |
| 44 | type the function is using. This is used for prologue and frame |
| 45 | analysis to compute correct stack frame layout. |
| 46 | |
| 47 | The MSB of the minimal symbol's "info" field is used for this purpose. |
| 48 | This field is already being used to store the symbol size, so the |
| 49 | assumption is that the symbol size cannot exceed 2^30. |
| 50 | |
| 51 | MSYMBOL_SET_RTC Actually sets the "RTC" bit. |
| 52 | MSYMBOL_SET_RTI Actually sets the "RTI" bit. |
| 53 | MSYMBOL_IS_RTC Tests the "RTC" bit in a minimal symbol. |
| 54 | MSYMBOL_IS_RTI Tests the "RTC" bit in a minimal symbol. |
| 55 | MSYMBOL_SIZE Returns the size of the minimal symbol, |
| 56 | i.e. the "info" field with the "special" bit |
| 57 | masked out. */ |
| 58 | |
| 59 | #define MSYMBOL_SET_RTC(msym) \ |
| 60 | MSYMBOL_INFO (msym) = (char *) (((long) MSYMBOL_INFO (msym)) \ |
| 61 | | 0x80000000) |
| 62 | |
| 63 | #define MSYMBOL_SET_RTI(msym) \ |
| 64 | MSYMBOL_INFO (msym) = (char *) (((long) MSYMBOL_INFO (msym)) \ |
| 65 | | 0x40000000) |
| 66 | |
| 67 | #define MSYMBOL_IS_RTC(msym) \ |
| 68 | (((long) MSYMBOL_INFO (msym) & 0x80000000) != 0) |
| 69 | |
| 70 | #define MSYMBOL_IS_RTI(msym) \ |
| 71 | (((long) MSYMBOL_INFO (msym) & 0x40000000) != 0) |
| 72 | |
| 73 | #define MSYMBOL_SIZE(msym) \ |
| 74 | ((long) MSYMBOL_INFO (msym) & 0x3fffffff) |
| 75 | |
| 76 | enum insn_return_kind { |
| 77 | RETURN_RTS, |
| 78 | RETURN_RTC, |
| 79 | RETURN_RTI |
| 80 | }; |
| 81 | |
| 82 | |
| 83 | /* Register numbers of various important registers. |
| 84 | Note that some of these values are "real" register numbers, |
| 85 | and correspond to the general registers of the machine, |
| 86 | and some are "phony" register numbers which are too large |
| 87 | to be actual register numbers as far as the user is concerned |
| 88 | but do serve to get the desired values when passed to read_register. */ |
| 89 | |
| 90 | #define HARD_X_REGNUM 0 |
| 91 | #define HARD_D_REGNUM 1 |
| 92 | #define HARD_Y_REGNUM 2 |
| 93 | #define HARD_SP_REGNUM 3 |
| 94 | #define HARD_PC_REGNUM 4 |
| 95 | |
| 96 | #define HARD_A_REGNUM 5 |
| 97 | #define HARD_B_REGNUM 6 |
| 98 | #define HARD_CCR_REGNUM 7 |
| 99 | |
| 100 | /* 68HC12 page number register. |
| 101 | Note: to keep a compatibility with gcc register naming, we must |
| 102 | not have to rename FP and other soft registers. The page register |
| 103 | is a real hard register and must therefore be counted by NUM_REGS. |
| 104 | For this it has the same number as Z register (which is not used). */ |
| 105 | #define HARD_PAGE_REGNUM 8 |
| 106 | #define M68HC11_LAST_HARD_REG (HARD_PAGE_REGNUM) |
| 107 | |
| 108 | /* Z is replaced by X or Y by gcc during machine reorg. |
| 109 | ??? There is no way to get it and even know whether |
| 110 | it's in X or Y or in ZS. */ |
| 111 | #define SOFT_Z_REGNUM 8 |
| 112 | |
| 113 | /* Soft registers. These registers are special. There are treated |
| 114 | like normal hard registers by gcc and gdb (ie, within dwarf2 info). |
| 115 | They are physically located in memory. */ |
| 116 | #define SOFT_FP_REGNUM 9 |
| 117 | #define SOFT_TMP_REGNUM 10 |
| 118 | #define SOFT_ZS_REGNUM 11 |
| 119 | #define SOFT_XY_REGNUM 12 |
| 120 | #define SOFT_UNUSED_REGNUM 13 |
| 121 | #define SOFT_D1_REGNUM 14 |
| 122 | #define SOFT_D32_REGNUM (SOFT_D1_REGNUM+31) |
| 123 | #define M68HC11_MAX_SOFT_REGS 32 |
| 124 | |
| 125 | #define M68HC11_NUM_REGS (8) |
| 126 | #define M68HC11_NUM_PSEUDO_REGS (M68HC11_MAX_SOFT_REGS+5) |
| 127 | #define M68HC11_ALL_REGS (M68HC11_NUM_REGS+M68HC11_NUM_PSEUDO_REGS) |
| 128 | |
| 129 | #define M68HC11_REG_SIZE (2) |
| 130 | |
| 131 | #define M68HC12_NUM_REGS (9) |
| 132 | #define M68HC12_NUM_PSEUDO_REGS ((M68HC11_MAX_SOFT_REGS+5)+1-1) |
| 133 | #define M68HC12_HARD_PC_REGNUM (SOFT_D32_REGNUM+1) |
| 134 | |
| 135 | struct insn_sequence; |
| 136 | struct gdbarch_tdep |
| 137 | { |
| 138 | /* Stack pointer correction value. For 68hc11, the stack pointer points |
| 139 | to the next push location. An offset of 1 must be applied to obtain |
| 140 | the address where the last value is saved. For 68hc12, the stack |
| 141 | pointer points to the last value pushed. No offset is necessary. */ |
| 142 | int stack_correction; |
| 143 | |
| 144 | /* Description of instructions in the prologue. */ |
| 145 | struct insn_sequence *prologue; |
| 146 | |
| 147 | /* True if the page memory bank register is available |
| 148 | and must be used. */ |
| 149 | int use_page_register; |
| 150 | |
| 151 | /* ELF flags for ABI. */ |
| 152 | int elf_flags; |
| 153 | }; |
| 154 | |
| 155 | #define M6811_TDEP gdbarch_tdep (current_gdbarch) |
| 156 | #define STACK_CORRECTION (M6811_TDEP->stack_correction) |
| 157 | #define USE_PAGE_REGISTER (M6811_TDEP->use_page_register) |
| 158 | |
| 159 | struct frame_extra_info |
| 160 | { |
| 161 | CORE_ADDR return_pc; |
| 162 | int frameless; |
| 163 | int size; |
| 164 | enum insn_return_kind return_kind; |
| 165 | }; |
| 166 | |
| 167 | /* Table of registers for 68HC11. This includes the hard registers |
| 168 | and the soft registers used by GCC. */ |
| 169 | static char * |
| 170 | m68hc11_register_names[] = |
| 171 | { |
| 172 | "x", "d", "y", "sp", "pc", "a", "b", |
| 173 | "ccr", "page", "frame","tmp", "zs", "xy", 0, |
| 174 | "d1", "d2", "d3", "d4", "d5", "d6", "d7", |
| 175 | "d8", "d9", "d10", "d11", "d12", "d13", "d14", |
| 176 | "d15", "d16", "d17", "d18", "d19", "d20", "d21", |
| 177 | "d22", "d23", "d24", "d25", "d26", "d27", "d28", |
| 178 | "d29", "d30", "d31", "d32" |
| 179 | }; |
| 180 | |
| 181 | struct m68hc11_soft_reg |
| 182 | { |
| 183 | const char *name; |
| 184 | CORE_ADDR addr; |
| 185 | }; |
| 186 | |
| 187 | static struct m68hc11_soft_reg soft_regs[M68HC11_ALL_REGS]; |
| 188 | |
| 189 | #define M68HC11_FP_ADDR soft_regs[SOFT_FP_REGNUM].addr |
| 190 | |
| 191 | static int soft_min_addr; |
| 192 | static int soft_max_addr; |
| 193 | static int soft_reg_initialized = 0; |
| 194 | |
| 195 | /* Look in the symbol table for the address of a pseudo register |
| 196 | in memory. If we don't find it, pretend the register is not used |
| 197 | and not available. */ |
| 198 | static void |
| 199 | m68hc11_get_register_info (struct m68hc11_soft_reg *reg, const char *name) |
| 200 | { |
| 201 | struct minimal_symbol *msymbol; |
| 202 | |
| 203 | msymbol = lookup_minimal_symbol (name, NULL, NULL); |
| 204 | if (msymbol) |
| 205 | { |
| 206 | reg->addr = SYMBOL_VALUE_ADDRESS (msymbol); |
| 207 | reg->name = xstrdup (name); |
| 208 | |
| 209 | /* Keep track of the address range for soft registers. */ |
| 210 | if (reg->addr < (CORE_ADDR) soft_min_addr) |
| 211 | soft_min_addr = reg->addr; |
| 212 | if (reg->addr > (CORE_ADDR) soft_max_addr) |
| 213 | soft_max_addr = reg->addr; |
| 214 | } |
| 215 | else |
| 216 | { |
| 217 | reg->name = 0; |
| 218 | reg->addr = 0; |
| 219 | } |
| 220 | } |
| 221 | |
| 222 | /* Initialize the table of soft register addresses according |
| 223 | to the symbol table. */ |
| 224 | static void |
| 225 | m68hc11_initialize_register_info (void) |
| 226 | { |
| 227 | int i; |
| 228 | |
| 229 | if (soft_reg_initialized) |
| 230 | return; |
| 231 | |
| 232 | soft_min_addr = INT_MAX; |
| 233 | soft_max_addr = 0; |
| 234 | for (i = 0; i < M68HC11_ALL_REGS; i++) |
| 235 | { |
| 236 | soft_regs[i].name = 0; |
| 237 | } |
| 238 | |
| 239 | m68hc11_get_register_info (&soft_regs[SOFT_FP_REGNUM], "_.frame"); |
| 240 | m68hc11_get_register_info (&soft_regs[SOFT_TMP_REGNUM], "_.tmp"); |
| 241 | m68hc11_get_register_info (&soft_regs[SOFT_ZS_REGNUM], "_.z"); |
| 242 | soft_regs[SOFT_Z_REGNUM] = soft_regs[SOFT_ZS_REGNUM]; |
| 243 | m68hc11_get_register_info (&soft_regs[SOFT_XY_REGNUM], "_.xy"); |
| 244 | |
| 245 | for (i = SOFT_D1_REGNUM; i < M68HC11_MAX_SOFT_REGS; i++) |
| 246 | { |
| 247 | char buf[10]; |
| 248 | |
| 249 | sprintf (buf, "_.d%d", i - SOFT_D1_REGNUM + 1); |
| 250 | m68hc11_get_register_info (&soft_regs[i], buf); |
| 251 | } |
| 252 | |
| 253 | if (soft_regs[SOFT_FP_REGNUM].name == 0) |
| 254 | { |
| 255 | warning ("No frame soft register found in the symbol table.\n"); |
| 256 | warning ("Stack backtrace will not work.\n"); |
| 257 | } |
| 258 | soft_reg_initialized = 1; |
| 259 | } |
| 260 | |
| 261 | /* Given an address in memory, return the soft register number if |
| 262 | that address corresponds to a soft register. Returns -1 if not. */ |
| 263 | static int |
| 264 | m68hc11_which_soft_register (CORE_ADDR addr) |
| 265 | { |
| 266 | int i; |
| 267 | |
| 268 | if (addr < soft_min_addr || addr > soft_max_addr) |
| 269 | return -1; |
| 270 | |
| 271 | for (i = SOFT_FP_REGNUM; i < M68HC11_ALL_REGS; i++) |
| 272 | { |
| 273 | if (soft_regs[i].name && soft_regs[i].addr == addr) |
| 274 | return i; |
| 275 | } |
| 276 | return -1; |
| 277 | } |
| 278 | |
| 279 | /* Fetch a pseudo register. The 68hc11 soft registers are treated like |
| 280 | pseudo registers. They are located in memory. Translate the register |
| 281 | fetch into a memory read. */ |
| 282 | static void |
| 283 | m68hc11_pseudo_register_read (struct gdbarch *gdbarch, |
| 284 | struct regcache *regcache, |
| 285 | int regno, void *buf) |
| 286 | { |
| 287 | /* The PC is a pseudo reg only for 68HC12 with the memory bank |
| 288 | addressing mode. */ |
| 289 | if (regno == M68HC12_HARD_PC_REGNUM) |
| 290 | { |
| 291 | const int regsize = TYPE_LENGTH (builtin_type_uint32); |
| 292 | CORE_ADDR pc = read_register (HARD_PC_REGNUM); |
| 293 | int page = read_register (HARD_PAGE_REGNUM); |
| 294 | |
| 295 | if (pc >= 0x8000 && pc < 0xc000) |
| 296 | { |
| 297 | pc -= 0x8000; |
| 298 | pc += (page << 14); |
| 299 | pc += 0x1000000; |
| 300 | } |
| 301 | store_unsigned_integer (buf, regsize, pc); |
| 302 | return; |
| 303 | } |
| 304 | |
| 305 | m68hc11_initialize_register_info (); |
| 306 | |
| 307 | /* Fetch a soft register: translate into a memory read. */ |
| 308 | if (soft_regs[regno].name) |
| 309 | { |
| 310 | target_read_memory (soft_regs[regno].addr, buf, 2); |
| 311 | } |
| 312 | else |
| 313 | { |
| 314 | memset (buf, 0, 2); |
| 315 | } |
| 316 | } |
| 317 | |
| 318 | /* Store a pseudo register. Translate the register store |
| 319 | into a memory write. */ |
| 320 | static void |
| 321 | m68hc11_pseudo_register_write (struct gdbarch *gdbarch, |
| 322 | struct regcache *regcache, |
| 323 | int regno, const void *buf) |
| 324 | { |
| 325 | /* The PC is a pseudo reg only for 68HC12 with the memory bank |
| 326 | addressing mode. */ |
| 327 | if (regno == M68HC12_HARD_PC_REGNUM) |
| 328 | { |
| 329 | const int regsize = TYPE_LENGTH (builtin_type_uint32); |
| 330 | char *tmp = alloca (regsize); |
| 331 | CORE_ADDR pc; |
| 332 | |
| 333 | memcpy (tmp, buf, regsize); |
| 334 | pc = extract_unsigned_integer (tmp, regsize); |
| 335 | if (pc >= 0x1000000) |
| 336 | { |
| 337 | pc -= 0x1000000; |
| 338 | write_register (HARD_PAGE_REGNUM, (pc >> 14) & 0x0ff); |
| 339 | pc &= 0x03fff; |
| 340 | write_register (HARD_PC_REGNUM, pc + 0x8000); |
| 341 | } |
| 342 | else |
| 343 | write_register (HARD_PC_REGNUM, pc); |
| 344 | return; |
| 345 | } |
| 346 | |
| 347 | m68hc11_initialize_register_info (); |
| 348 | |
| 349 | /* Store a soft register: translate into a memory write. */ |
| 350 | if (soft_regs[regno].name) |
| 351 | { |
| 352 | const int regsize = 2; |
| 353 | char *tmp = alloca (regsize); |
| 354 | memcpy (tmp, buf, regsize); |
| 355 | target_write_memory (soft_regs[regno].addr, tmp, regsize); |
| 356 | } |
| 357 | } |
| 358 | |
| 359 | static const char * |
| 360 | m68hc11_register_name (int reg_nr) |
| 361 | { |
| 362 | if (reg_nr == M68HC12_HARD_PC_REGNUM && USE_PAGE_REGISTER) |
| 363 | return "pc"; |
| 364 | if (reg_nr == HARD_PC_REGNUM && USE_PAGE_REGISTER) |
| 365 | return "ppc"; |
| 366 | |
| 367 | if (reg_nr < 0) |
| 368 | return NULL; |
| 369 | if (reg_nr >= M68HC11_ALL_REGS) |
| 370 | return NULL; |
| 371 | |
| 372 | /* If we don't know the address of a soft register, pretend it |
| 373 | does not exist. */ |
| 374 | if (reg_nr > M68HC11_LAST_HARD_REG && soft_regs[reg_nr].name == 0) |
| 375 | return NULL; |
| 376 | return m68hc11_register_names[reg_nr]; |
| 377 | } |
| 378 | |
| 379 | static const unsigned char * |
| 380 | m68hc11_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr) |
| 381 | { |
| 382 | static unsigned char breakpoint[] = {0x0}; |
| 383 | |
| 384 | *lenptr = sizeof (breakpoint); |
| 385 | return breakpoint; |
| 386 | } |
| 387 | |
| 388 | /* Immediately after a function call, return the saved pc before the frame |
| 389 | is setup. */ |
| 390 | |
| 391 | static CORE_ADDR |
| 392 | m68hc11_saved_pc_after_call (struct frame_info *frame) |
| 393 | { |
| 394 | CORE_ADDR addr; |
| 395 | |
| 396 | addr = read_register (HARD_SP_REGNUM) + STACK_CORRECTION; |
| 397 | addr &= 0x0ffff; |
| 398 | return read_memory_integer (addr, 2) & 0x0FFFF; |
| 399 | } |
| 400 | |
| 401 | static CORE_ADDR |
| 402 | m68hc11_frame_saved_pc (struct frame_info *frame) |
| 403 | { |
| 404 | return get_frame_extra_info (frame)->return_pc; |
| 405 | } |
| 406 | |
| 407 | static CORE_ADDR |
| 408 | m68hc11_frame_args_address (struct frame_info *frame) |
| 409 | { |
| 410 | CORE_ADDR addr; |
| 411 | |
| 412 | addr = get_frame_base (frame) + get_frame_extra_info (frame)->size + STACK_CORRECTION + 2; |
| 413 | if (get_frame_extra_info (frame)->return_kind == RETURN_RTC) |
| 414 | addr += 1; |
| 415 | else if (get_frame_extra_info (frame)->return_kind == RETURN_RTI) |
| 416 | addr += 7; |
| 417 | |
| 418 | return addr; |
| 419 | } |
| 420 | |
| 421 | static CORE_ADDR |
| 422 | m68hc11_frame_locals_address (struct frame_info *frame) |
| 423 | { |
| 424 | return get_frame_base (frame); |
| 425 | } |
| 426 | |
| 427 | /* Discard from the stack the innermost frame, restoring all saved |
| 428 | registers. */ |
| 429 | |
| 430 | static void |
| 431 | m68hc11_pop_frame (void) |
| 432 | { |
| 433 | register struct frame_info *frame = get_current_frame (); |
| 434 | register CORE_ADDR fp, sp; |
| 435 | register int regnum; |
| 436 | |
| 437 | if (DEPRECATED_PC_IN_CALL_DUMMY (get_frame_pc (frame), |
| 438 | get_frame_base (frame), |
| 439 | get_frame_base (frame))) |
| 440 | generic_pop_dummy_frame (); |
| 441 | else |
| 442 | { |
| 443 | fp = get_frame_base (frame); |
| 444 | FRAME_INIT_SAVED_REGS (frame); |
| 445 | |
| 446 | /* Copy regs from where they were saved in the frame. */ |
| 447 | for (regnum = 0; regnum < M68HC11_ALL_REGS; regnum++) |
| 448 | if (get_frame_saved_regs (frame)[regnum]) |
| 449 | write_register (regnum, |
| 450 | read_memory_integer (get_frame_saved_regs (frame)[regnum], 2)); |
| 451 | |
| 452 | write_register (HARD_PC_REGNUM, get_frame_extra_info (frame)->return_pc); |
| 453 | sp = (fp + get_frame_extra_info (frame)->size + 2) & 0x0ffff; |
| 454 | write_register (HARD_SP_REGNUM, sp); |
| 455 | } |
| 456 | flush_cached_frames (); |
| 457 | } |
| 458 | |
| 459 | \f |
| 460 | /* 68HC11 & 68HC12 prologue analysis. |
| 461 | |
| 462 | */ |
| 463 | #define MAX_CODES 12 |
| 464 | |
| 465 | /* 68HC11 opcodes. */ |
| 466 | #undef M6811_OP_PAGE2 |
| 467 | #define M6811_OP_PAGE2 (0x18) |
| 468 | #define M6811_OP_LDX (0xde) |
| 469 | #define M6811_OP_PSHX (0x3c) |
| 470 | #define M6811_OP_STS (0x9f) |
| 471 | #define M6811_OP_TSX (0x30) |
| 472 | #define M6811_OP_XGDX (0x8f) |
| 473 | #define M6811_OP_ADDD (0xc3) |
| 474 | #define M6811_OP_TXS (0x35) |
| 475 | #define M6811_OP_DES (0x34) |
| 476 | |
| 477 | /* 68HC12 opcodes. */ |
| 478 | #define M6812_OP_PAGE2 (0x18) |
| 479 | #define M6812_OP_MOVW (0x01) |
| 480 | #define M6812_PB_PSHW (0xae) |
| 481 | #define M6812_OP_STS (0x7f) |
| 482 | #define M6812_OP_LEAS (0x1b) |
| 483 | #define M6812_OP_PSHX (0x34) |
| 484 | #define M6812_OP_PSHY (0x35) |
| 485 | |
| 486 | /* Operand extraction. */ |
| 487 | #define OP_DIRECT (0x100) /* 8-byte direct addressing. */ |
| 488 | #define OP_IMM_LOW (0x200) /* Low part of 16-bit constant/address. */ |
| 489 | #define OP_IMM_HIGH (0x300) /* High part of 16-bit constant/address. */ |
| 490 | #define OP_PBYTE (0x400) /* 68HC12 indexed operand. */ |
| 491 | |
| 492 | /* Identification of the sequence. */ |
| 493 | enum m6811_seq_type |
| 494 | { |
| 495 | P_LAST = 0, |
| 496 | P_SAVE_REG, /* Save a register on the stack. */ |
| 497 | P_SET_FRAME, /* Setup the frame pointer. */ |
| 498 | P_LOCAL_1, /* Allocate 1 byte for locals. */ |
| 499 | P_LOCAL_2, /* Allocate 2 bytes for locals. */ |
| 500 | P_LOCAL_N /* Allocate N bytes for locals. */ |
| 501 | }; |
| 502 | |
| 503 | struct insn_sequence { |
| 504 | enum m6811_seq_type type; |
| 505 | unsigned length; |
| 506 | unsigned short code[MAX_CODES]; |
| 507 | }; |
| 508 | |
| 509 | /* Sequence of instructions in the 68HC11 function prologue. */ |
| 510 | static struct insn_sequence m6811_prologue[] = { |
| 511 | /* Sequences to save a soft-register. */ |
| 512 | { P_SAVE_REG, 3, { M6811_OP_LDX, OP_DIRECT, |
| 513 | M6811_OP_PSHX } }, |
| 514 | { P_SAVE_REG, 5, { M6811_OP_PAGE2, M6811_OP_LDX, OP_DIRECT, |
| 515 | M6811_OP_PAGE2, M6811_OP_PSHX } }, |
| 516 | |
| 517 | /* Sequences to allocate local variables. */ |
| 518 | { P_LOCAL_N, 7, { M6811_OP_TSX, |
| 519 | M6811_OP_XGDX, |
| 520 | M6811_OP_ADDD, OP_IMM_HIGH, OP_IMM_LOW, |
| 521 | M6811_OP_XGDX, |
| 522 | M6811_OP_TXS } }, |
| 523 | { P_LOCAL_N, 11, { M6811_OP_PAGE2, M6811_OP_TSX, |
| 524 | M6811_OP_PAGE2, M6811_OP_XGDX, |
| 525 | M6811_OP_ADDD, OP_IMM_HIGH, OP_IMM_LOW, |
| 526 | M6811_OP_PAGE2, M6811_OP_XGDX, |
| 527 | M6811_OP_PAGE2, M6811_OP_TXS } }, |
| 528 | { P_LOCAL_1, 1, { M6811_OP_DES } }, |
| 529 | { P_LOCAL_2, 1, { M6811_OP_PSHX } }, |
| 530 | { P_LOCAL_2, 2, { M6811_OP_PAGE2, M6811_OP_PSHX } }, |
| 531 | |
| 532 | /* Initialize the frame pointer. */ |
| 533 | { P_SET_FRAME, 2, { M6811_OP_STS, OP_DIRECT } }, |
| 534 | { P_LAST, 0, { 0 } } |
| 535 | }; |
| 536 | |
| 537 | |
| 538 | /* Sequence of instructions in the 68HC12 function prologue. */ |
| 539 | static struct insn_sequence m6812_prologue[] = { |
| 540 | { P_SAVE_REG, 5, { M6812_OP_PAGE2, M6812_OP_MOVW, M6812_PB_PSHW, |
| 541 | OP_IMM_HIGH, OP_IMM_LOW } }, |
| 542 | { P_SET_FRAME, 3, { M6812_OP_STS, OP_IMM_HIGH, OP_IMM_LOW } }, |
| 543 | { P_LOCAL_N, 2, { M6812_OP_LEAS, OP_PBYTE } }, |
| 544 | { P_LOCAL_2, 1, { M6812_OP_PSHX } }, |
| 545 | { P_LOCAL_2, 1, { M6812_OP_PSHY } }, |
| 546 | { P_LAST, 0 } |
| 547 | }; |
| 548 | |
| 549 | |
| 550 | /* Analyze the sequence of instructions starting at the given address. |
| 551 | Returns a pointer to the sequence when it is recognized and |
| 552 | the optional value (constant/address) associated with it. |
| 553 | Advance the pc for the next sequence. */ |
| 554 | static struct insn_sequence * |
| 555 | m68hc11_analyze_instruction (struct insn_sequence *seq, CORE_ADDR *pc, |
| 556 | CORE_ADDR *val) |
| 557 | { |
| 558 | unsigned char buffer[MAX_CODES]; |
| 559 | unsigned bufsize; |
| 560 | unsigned j; |
| 561 | CORE_ADDR cur_val; |
| 562 | short v = 0; |
| 563 | |
| 564 | bufsize = 0; |
| 565 | for (; seq->type != P_LAST; seq++) |
| 566 | { |
| 567 | cur_val = 0; |
| 568 | for (j = 0; j < seq->length; j++) |
| 569 | { |
| 570 | if (bufsize < j + 1) |
| 571 | { |
| 572 | buffer[bufsize] = read_memory_unsigned_integer (*pc + bufsize, |
| 573 | 1); |
| 574 | bufsize++; |
| 575 | } |
| 576 | /* Continue while we match the opcode. */ |
| 577 | if (seq->code[j] == buffer[j]) |
| 578 | continue; |
| 579 | |
| 580 | if ((seq->code[j] & 0xf00) == 0) |
| 581 | break; |
| 582 | |
| 583 | /* Extract a sequence parameter (address or constant). */ |
| 584 | switch (seq->code[j]) |
| 585 | { |
| 586 | case OP_DIRECT: |
| 587 | cur_val = (CORE_ADDR) buffer[j]; |
| 588 | break; |
| 589 | |
| 590 | case OP_IMM_HIGH: |
| 591 | cur_val = cur_val & 0x0ff; |
| 592 | cur_val |= (buffer[j] << 8); |
| 593 | break; |
| 594 | |
| 595 | case OP_IMM_LOW: |
| 596 | cur_val &= 0x0ff00; |
| 597 | cur_val |= buffer[j]; |
| 598 | break; |
| 599 | |
| 600 | case OP_PBYTE: |
| 601 | if ((buffer[j] & 0xE0) == 0x80) |
| 602 | { |
| 603 | v = buffer[j] & 0x1f; |
| 604 | if (v & 0x10) |
| 605 | v |= 0xfff0; |
| 606 | } |
| 607 | else if ((buffer[j] & 0xfe) == 0xf0) |
| 608 | { |
| 609 | v = read_memory_unsigned_integer (*pc + j + 1, 1); |
| 610 | if (buffer[j] & 1) |
| 611 | v |= 0xff00; |
| 612 | *pc = *pc + 1; |
| 613 | } |
| 614 | else if (buffer[j] == 0xf2) |
| 615 | { |
| 616 | v = read_memory_unsigned_integer (*pc + j + 1, 2); |
| 617 | *pc = *pc + 2; |
| 618 | } |
| 619 | cur_val = v; |
| 620 | break; |
| 621 | } |
| 622 | } |
| 623 | |
| 624 | /* We have a full match. */ |
| 625 | if (j == seq->length) |
| 626 | { |
| 627 | *val = cur_val; |
| 628 | *pc = *pc + j; |
| 629 | return seq; |
| 630 | } |
| 631 | } |
| 632 | return 0; |
| 633 | } |
| 634 | |
| 635 | /* Return the instruction that the function at the PC is using. */ |
| 636 | static enum insn_return_kind |
| 637 | m68hc11_get_return_insn (CORE_ADDR pc) |
| 638 | { |
| 639 | struct minimal_symbol *sym; |
| 640 | |
| 641 | /* A flag indicating that this is a STO_M68HC12_FAR or STO_M68HC12_INTERRUPT |
| 642 | function is stored by elfread.c in the high bit of the info field. |
| 643 | Use this to decide which instruction the function uses to return. */ |
| 644 | sym = lookup_minimal_symbol_by_pc (pc); |
| 645 | if (sym == 0) |
| 646 | return RETURN_RTS; |
| 647 | |
| 648 | if (MSYMBOL_IS_RTC (sym)) |
| 649 | return RETURN_RTC; |
| 650 | else if (MSYMBOL_IS_RTI (sym)) |
| 651 | return RETURN_RTI; |
| 652 | else |
| 653 | return RETURN_RTS; |
| 654 | } |
| 655 | |
| 656 | |
| 657 | /* Analyze the function prologue to find some information |
| 658 | about the function: |
| 659 | - the PC of the first line (for m68hc11_skip_prologue) |
| 660 | - the offset of the previous frame saved address (from current frame) |
| 661 | - the soft registers which are pushed. */ |
| 662 | static void |
| 663 | m68hc11_guess_from_prologue (CORE_ADDR pc, CORE_ADDR fp, |
| 664 | CORE_ADDR *first_line, |
| 665 | int *frame_offset, CORE_ADDR *pushed_regs) |
| 666 | { |
| 667 | CORE_ADDR save_addr; |
| 668 | CORE_ADDR func_end; |
| 669 | int size; |
| 670 | int found_frame_point; |
| 671 | int saved_reg; |
| 672 | CORE_ADDR first_pc; |
| 673 | int done = 0; |
| 674 | struct insn_sequence *seq_table; |
| 675 | |
| 676 | first_pc = get_pc_function_start (pc); |
| 677 | size = 0; |
| 678 | |
| 679 | m68hc11_initialize_register_info (); |
| 680 | if (first_pc == 0) |
| 681 | { |
| 682 | *frame_offset = 0; |
| 683 | *first_line = pc; |
| 684 | return; |
| 685 | } |
| 686 | |
| 687 | seq_table = gdbarch_tdep (current_gdbarch)->prologue; |
| 688 | |
| 689 | /* The 68hc11 stack is as follows: |
| 690 | |
| 691 | |
| 692 | | | |
| 693 | +-----------+ |
| 694 | | | |
| 695 | | args | |
| 696 | | | |
| 697 | +-----------+ |
| 698 | | PC-return | |
| 699 | +-----------+ |
| 700 | | Old frame | |
| 701 | +-----------+ |
| 702 | | | |
| 703 | | Locals | |
| 704 | | | |
| 705 | +-----------+ <--- current frame |
| 706 | | | |
| 707 | |
| 708 | With most processors (like 68K) the previous frame can be computed |
| 709 | easily because it is always at a fixed offset (see link/unlink). |
| 710 | That is, locals are accessed with negative offsets, arguments are |
| 711 | accessed with positive ones. Since 68hc11 only supports offsets |
| 712 | in the range [0..255], the frame is defined at the bottom of |
| 713 | locals (see picture). |
| 714 | |
| 715 | The purpose of the analysis made here is to find out the size |
| 716 | of locals in this function. An alternative to this is to use |
| 717 | DWARF2 info. This would be better but I don't know how to |
| 718 | access dwarf2 debug from this function. |
| 719 | |
| 720 | Walk from the function entry point to the point where we save |
| 721 | the frame. While walking instructions, compute the size of bytes |
| 722 | which are pushed. This gives us the index to access the previous |
| 723 | frame. |
| 724 | |
| 725 | We limit the search to 128 bytes so that the algorithm is bounded |
| 726 | in case of random and wrong code. We also stop and abort if |
| 727 | we find an instruction which is not supposed to appear in the |
| 728 | prologue (as generated by gcc 2.95, 2.96). |
| 729 | */ |
| 730 | pc = first_pc; |
| 731 | func_end = pc + 128; |
| 732 | found_frame_point = 0; |
| 733 | *frame_offset = 0; |
| 734 | save_addr = fp + STACK_CORRECTION; |
| 735 | while (!done && pc + 2 < func_end) |
| 736 | { |
| 737 | struct insn_sequence *seq; |
| 738 | CORE_ADDR val; |
| 739 | |
| 740 | seq = m68hc11_analyze_instruction (seq_table, &pc, &val); |
| 741 | if (seq == 0) |
| 742 | break; |
| 743 | |
| 744 | if (seq->type == P_SAVE_REG) |
| 745 | { |
| 746 | if (found_frame_point) |
| 747 | { |
| 748 | saved_reg = m68hc11_which_soft_register (val); |
| 749 | if (saved_reg < 0) |
| 750 | break; |
| 751 | |
| 752 | save_addr -= 2; |
| 753 | if (pushed_regs) |
| 754 | pushed_regs[saved_reg] = save_addr; |
| 755 | } |
| 756 | else |
| 757 | { |
| 758 | size += 2; |
| 759 | } |
| 760 | } |
| 761 | else if (seq->type == P_SET_FRAME) |
| 762 | { |
| 763 | found_frame_point = 1; |
| 764 | *frame_offset = size; |
| 765 | } |
| 766 | else if (seq->type == P_LOCAL_1) |
| 767 | { |
| 768 | size += 1; |
| 769 | } |
| 770 | else if (seq->type == P_LOCAL_2) |
| 771 | { |
| 772 | size += 2; |
| 773 | } |
| 774 | else if (seq->type == P_LOCAL_N) |
| 775 | { |
| 776 | /* Stack pointer is decremented for the allocation. */ |
| 777 | if (val & 0x8000) |
| 778 | size -= (int) (val) | 0xffff0000; |
| 779 | else |
| 780 | size -= val; |
| 781 | } |
| 782 | } |
| 783 | *first_line = pc; |
| 784 | } |
| 785 | |
| 786 | static CORE_ADDR |
| 787 | m68hc11_skip_prologue (CORE_ADDR pc) |
| 788 | { |
| 789 | CORE_ADDR func_addr, func_end; |
| 790 | struct symtab_and_line sal; |
| 791 | int frame_offset; |
| 792 | |
| 793 | /* If we have line debugging information, then the end of the |
| 794 | prologue should be the first assembly instruction of the |
| 795 | first source line. */ |
| 796 | if (find_pc_partial_function (pc, NULL, &func_addr, &func_end)) |
| 797 | { |
| 798 | sal = find_pc_line (func_addr, 0); |
| 799 | if (sal.end && sal.end < func_end) |
| 800 | return sal.end; |
| 801 | } |
| 802 | |
| 803 | m68hc11_guess_from_prologue (pc, 0, &pc, &frame_offset, 0); |
| 804 | return pc; |
| 805 | } |
| 806 | |
| 807 | /* Given a GDB frame, determine the address of the calling function's |
| 808 | frame. This will be used to create a new GDB frame struct, and |
| 809 | then INIT_EXTRA_FRAME_INFO and DEPRECATED_INIT_FRAME_PC will be |
| 810 | called for the new frame. */ |
| 811 | |
| 812 | static CORE_ADDR |
| 813 | m68hc11_frame_chain (struct frame_info *frame) |
| 814 | { |
| 815 | CORE_ADDR addr; |
| 816 | |
| 817 | if (DEPRECATED_PC_IN_CALL_DUMMY (get_frame_pc (frame), |
| 818 | get_frame_base (frame), |
| 819 | get_frame_base (frame))) |
| 820 | return get_frame_base (frame); /* dummy frame same as caller's frame */ |
| 821 | |
| 822 | if (get_frame_extra_info (frame)->return_pc == 0 |
| 823 | || inside_entry_file (get_frame_extra_info (frame)->return_pc)) |
| 824 | return (CORE_ADDR) 0; |
| 825 | |
| 826 | if (get_frame_base (frame) == 0) |
| 827 | { |
| 828 | return (CORE_ADDR) 0; |
| 829 | } |
| 830 | |
| 831 | addr = get_frame_base (frame) + get_frame_extra_info (frame)->size + STACK_CORRECTION - 2; |
| 832 | addr = read_memory_unsigned_integer (addr, 2) & 0x0FFFF; |
| 833 | return addr; |
| 834 | } |
| 835 | |
| 836 | /* Put here the code to store, into a struct frame_saved_regs, the |
| 837 | addresses of the saved registers of frame described by FRAME_INFO. |
| 838 | This includes special registers such as pc and fp saved in special |
| 839 | ways in the stack frame. sp is even more special: the address we |
| 840 | return for it IS the sp for the next frame. */ |
| 841 | static void |
| 842 | m68hc11_frame_init_saved_regs (struct frame_info *fi) |
| 843 | { |
| 844 | CORE_ADDR pc; |
| 845 | CORE_ADDR addr; |
| 846 | |
| 847 | if (get_frame_saved_regs (fi) == NULL) |
| 848 | frame_saved_regs_zalloc (fi); |
| 849 | else |
| 850 | memset (get_frame_saved_regs (fi), 0, SIZEOF_FRAME_SAVED_REGS); |
| 851 | |
| 852 | pc = get_frame_pc (fi); |
| 853 | get_frame_extra_info (fi)->return_kind = m68hc11_get_return_insn (pc); |
| 854 | m68hc11_guess_from_prologue (pc, get_frame_base (fi), &pc, |
| 855 | &get_frame_extra_info (fi)->size, |
| 856 | get_frame_saved_regs (fi)); |
| 857 | |
| 858 | addr = get_frame_base (fi) + get_frame_extra_info (fi)->size + STACK_CORRECTION; |
| 859 | if (soft_regs[SOFT_FP_REGNUM].name) |
| 860 | get_frame_saved_regs (fi)[SOFT_FP_REGNUM] = addr - 2; |
| 861 | |
| 862 | /* Take into account how the function was called/returns. */ |
| 863 | if (get_frame_extra_info (fi)->return_kind == RETURN_RTC) |
| 864 | { |
| 865 | get_frame_saved_regs (fi)[HARD_PAGE_REGNUM] = addr; |
| 866 | addr++; |
| 867 | } |
| 868 | else if (get_frame_extra_info (fi)->return_kind == RETURN_RTI) |
| 869 | { |
| 870 | get_frame_saved_regs (fi)[HARD_CCR_REGNUM] = addr; |
| 871 | get_frame_saved_regs (fi)[HARD_D_REGNUM] = addr + 1; |
| 872 | get_frame_saved_regs (fi)[HARD_X_REGNUM] = addr + 3; |
| 873 | get_frame_saved_regs (fi)[HARD_Y_REGNUM] = addr + 5; |
| 874 | addr += 7; |
| 875 | } |
| 876 | get_frame_saved_regs (fi)[HARD_SP_REGNUM] = addr; |
| 877 | get_frame_saved_regs (fi)[HARD_PC_REGNUM] = get_frame_saved_regs (fi)[HARD_SP_REGNUM]; |
| 878 | } |
| 879 | |
| 880 | static void |
| 881 | m68hc11_init_extra_frame_info (int fromleaf, struct frame_info *fi) |
| 882 | { |
| 883 | CORE_ADDR addr; |
| 884 | |
| 885 | frame_extra_info_zalloc (fi, sizeof (struct frame_extra_info)); |
| 886 | |
| 887 | if (get_next_frame (fi)) |
| 888 | deprecated_update_frame_pc_hack (fi, FRAME_SAVED_PC (get_next_frame (fi))); |
| 889 | |
| 890 | m68hc11_frame_init_saved_regs (fi); |
| 891 | |
| 892 | if (fromleaf) |
| 893 | { |
| 894 | get_frame_extra_info (fi)->return_kind = m68hc11_get_return_insn (get_frame_pc (fi)); |
| 895 | get_frame_extra_info (fi)->return_pc = m68hc11_saved_pc_after_call (fi); |
| 896 | } |
| 897 | else |
| 898 | { |
| 899 | addr = get_frame_saved_regs (fi)[HARD_PC_REGNUM]; |
| 900 | addr = read_memory_unsigned_integer (addr, 2) & 0x0ffff; |
| 901 | |
| 902 | /* Take into account the 68HC12 specific call (PC + page). */ |
| 903 | if (get_frame_extra_info (fi)->return_kind == RETURN_RTC |
| 904 | && addr >= 0x08000 && addr < 0x0c000 |
| 905 | && USE_PAGE_REGISTER) |
| 906 | { |
| 907 | CORE_ADDR page_addr = get_frame_saved_regs (fi)[HARD_PAGE_REGNUM]; |
| 908 | |
| 909 | unsigned page = read_memory_unsigned_integer (page_addr, 1); |
| 910 | addr -= 0x08000; |
| 911 | addr += ((page & 0x0ff) << 14); |
| 912 | addr += 0x1000000; |
| 913 | } |
| 914 | get_frame_extra_info (fi)->return_pc = addr; |
| 915 | } |
| 916 | } |
| 917 | |
| 918 | /* Same as 'info reg' but prints the registers in a different way. */ |
| 919 | static void |
| 920 | show_regs (char *args, int from_tty) |
| 921 | { |
| 922 | int ccr = read_register (HARD_CCR_REGNUM); |
| 923 | int i; |
| 924 | int nr; |
| 925 | |
| 926 | printf_filtered ("PC=%04x SP=%04x FP=%04x CCR=%02x %c%c%c%c%c%c%c%c\n", |
| 927 | (int) read_register (HARD_PC_REGNUM), |
| 928 | (int) read_register (HARD_SP_REGNUM), |
| 929 | (int) read_register (SOFT_FP_REGNUM), |
| 930 | ccr, |
| 931 | ccr & M6811_S_BIT ? 'S' : '-', |
| 932 | ccr & M6811_X_BIT ? 'X' : '-', |
| 933 | ccr & M6811_H_BIT ? 'H' : '-', |
| 934 | ccr & M6811_I_BIT ? 'I' : '-', |
| 935 | ccr & M6811_N_BIT ? 'N' : '-', |
| 936 | ccr & M6811_Z_BIT ? 'Z' : '-', |
| 937 | ccr & M6811_V_BIT ? 'V' : '-', |
| 938 | ccr & M6811_C_BIT ? 'C' : '-'); |
| 939 | |
| 940 | printf_filtered ("D=%04x IX=%04x IY=%04x", |
| 941 | (int) read_register (HARD_D_REGNUM), |
| 942 | (int) read_register (HARD_X_REGNUM), |
| 943 | (int) read_register (HARD_Y_REGNUM)); |
| 944 | |
| 945 | if (USE_PAGE_REGISTER) |
| 946 | { |
| 947 | printf_filtered (" Page=%02x", |
| 948 | (int) read_register (HARD_PAGE_REGNUM)); |
| 949 | } |
| 950 | printf_filtered ("\n"); |
| 951 | |
| 952 | nr = 0; |
| 953 | for (i = SOFT_D1_REGNUM; i < M68HC11_ALL_REGS; i++) |
| 954 | { |
| 955 | /* Skip registers which are not defined in the symbol table. */ |
| 956 | if (soft_regs[i].name == 0) |
| 957 | continue; |
| 958 | |
| 959 | printf_filtered ("D%d=%04x", |
| 960 | i - SOFT_D1_REGNUM + 1, |
| 961 | (int) read_register (i)); |
| 962 | nr++; |
| 963 | if ((nr % 8) == 7) |
| 964 | printf_filtered ("\n"); |
| 965 | else |
| 966 | printf_filtered (" "); |
| 967 | } |
| 968 | if (nr && (nr % 8) != 7) |
| 969 | printf_filtered ("\n"); |
| 970 | } |
| 971 | |
| 972 | static CORE_ADDR |
| 973 | m68hc11_stack_align (CORE_ADDR addr) |
| 974 | { |
| 975 | return ((addr + 1) & -2); |
| 976 | } |
| 977 | |
| 978 | static CORE_ADDR |
| 979 | m68hc11_push_arguments (int nargs, |
| 980 | struct value **args, |
| 981 | CORE_ADDR sp, |
| 982 | int struct_return, |
| 983 | CORE_ADDR struct_addr) |
| 984 | { |
| 985 | int stack_alloc; |
| 986 | int argnum; |
| 987 | int first_stack_argnum; |
| 988 | int stack_offset; |
| 989 | struct type *type; |
| 990 | char *val; |
| 991 | int len; |
| 992 | |
| 993 | stack_alloc = 0; |
| 994 | first_stack_argnum = 0; |
| 995 | if (struct_return) |
| 996 | { |
| 997 | /* The struct is allocated on the stack and gdb used the stack |
| 998 | pointer for the address of that struct. We must apply the |
| 999 | stack offset on the address. */ |
| 1000 | write_register (HARD_D_REGNUM, struct_addr + STACK_CORRECTION); |
| 1001 | } |
| 1002 | else if (nargs > 0) |
| 1003 | { |
| 1004 | type = VALUE_TYPE (args[0]); |
| 1005 | len = TYPE_LENGTH (type); |
| 1006 | |
| 1007 | /* First argument is passed in D and X registers. */ |
| 1008 | if (len <= 4) |
| 1009 | { |
| 1010 | LONGEST v = extract_unsigned_integer (VALUE_CONTENTS (args[0]), len); |
| 1011 | first_stack_argnum = 1; |
| 1012 | write_register (HARD_D_REGNUM, v); |
| 1013 | if (len > 2) |
| 1014 | { |
| 1015 | v >>= 16; |
| 1016 | write_register (HARD_X_REGNUM, v); |
| 1017 | } |
| 1018 | } |
| 1019 | } |
| 1020 | for (argnum = first_stack_argnum; argnum < nargs; argnum++) |
| 1021 | { |
| 1022 | type = VALUE_TYPE (args[argnum]); |
| 1023 | stack_alloc += (TYPE_LENGTH (type) + 1) & -2; |
| 1024 | } |
| 1025 | sp -= stack_alloc; |
| 1026 | |
| 1027 | stack_offset = STACK_CORRECTION; |
| 1028 | for (argnum = first_stack_argnum; argnum < nargs; argnum++) |
| 1029 | { |
| 1030 | type = VALUE_TYPE (args[argnum]); |
| 1031 | len = TYPE_LENGTH (type); |
| 1032 | |
| 1033 | val = (char*) VALUE_CONTENTS (args[argnum]); |
| 1034 | write_memory (sp + stack_offset, val, len); |
| 1035 | stack_offset += len; |
| 1036 | if (len & 1) |
| 1037 | { |
| 1038 | static char zero = 0; |
| 1039 | |
| 1040 | write_memory (sp + stack_offset, &zero, 1); |
| 1041 | stack_offset++; |
| 1042 | } |
| 1043 | } |
| 1044 | return sp; |
| 1045 | } |
| 1046 | |
| 1047 | |
| 1048 | /* Return a location where we can set a breakpoint that will be hit |
| 1049 | when an inferior function call returns. */ |
| 1050 | CORE_ADDR |
| 1051 | m68hc11_call_dummy_address (void) |
| 1052 | { |
| 1053 | return entry_point_address (); |
| 1054 | } |
| 1055 | |
| 1056 | static struct type * |
| 1057 | m68hc11_register_virtual_type (int reg_nr) |
| 1058 | { |
| 1059 | switch (reg_nr) |
| 1060 | { |
| 1061 | case HARD_PAGE_REGNUM: |
| 1062 | case HARD_A_REGNUM: |
| 1063 | case HARD_B_REGNUM: |
| 1064 | case HARD_CCR_REGNUM: |
| 1065 | return builtin_type_uint8; |
| 1066 | |
| 1067 | case M68HC12_HARD_PC_REGNUM: |
| 1068 | return builtin_type_uint32; |
| 1069 | |
| 1070 | default: |
| 1071 | return builtin_type_uint16; |
| 1072 | } |
| 1073 | } |
| 1074 | |
| 1075 | static void |
| 1076 | m68hc11_store_struct_return (CORE_ADDR addr, CORE_ADDR sp) |
| 1077 | { |
| 1078 | /* The struct address computed by gdb is on the stack. |
| 1079 | It uses the stack pointer so we must apply the stack |
| 1080 | correction offset. */ |
| 1081 | write_register (HARD_D_REGNUM, addr + STACK_CORRECTION); |
| 1082 | } |
| 1083 | |
| 1084 | static void |
| 1085 | m68hc11_store_return_value (struct type *type, char *valbuf) |
| 1086 | { |
| 1087 | int len; |
| 1088 | |
| 1089 | len = TYPE_LENGTH (type); |
| 1090 | |
| 1091 | /* First argument is passed in D and X registers. */ |
| 1092 | if (len <= 4) |
| 1093 | { |
| 1094 | LONGEST v = extract_unsigned_integer (valbuf, len); |
| 1095 | |
| 1096 | write_register (HARD_D_REGNUM, v); |
| 1097 | if (len > 2) |
| 1098 | { |
| 1099 | v >>= 16; |
| 1100 | write_register (HARD_X_REGNUM, v); |
| 1101 | } |
| 1102 | } |
| 1103 | else |
| 1104 | error ("return of value > 4 is not supported."); |
| 1105 | } |
| 1106 | |
| 1107 | |
| 1108 | /* Given a return value in `regbuf' with a type `type', |
| 1109 | extract and copy its value into `valbuf'. */ |
| 1110 | |
| 1111 | static void |
| 1112 | m68hc11_extract_return_value (struct type *type, |
| 1113 | char *regbuf, |
| 1114 | char *valbuf) |
| 1115 | { |
| 1116 | int len = TYPE_LENGTH (type); |
| 1117 | |
| 1118 | switch (len) |
| 1119 | { |
| 1120 | case 1: |
| 1121 | memcpy (valbuf, ®buf[HARD_D_REGNUM * 2 + 1], len); |
| 1122 | break; |
| 1123 | |
| 1124 | case 2: |
| 1125 | memcpy (valbuf, ®buf[HARD_D_REGNUM * 2], len); |
| 1126 | break; |
| 1127 | |
| 1128 | case 3: |
| 1129 | memcpy (&valbuf[0], ®buf[HARD_X_REGNUM * 2 + 1], 1); |
| 1130 | memcpy (&valbuf[1], ®buf[HARD_D_REGNUM * 2], 2); |
| 1131 | break; |
| 1132 | |
| 1133 | case 4: |
| 1134 | memcpy (&valbuf[0], ®buf[HARD_X_REGNUM * 2], 2); |
| 1135 | memcpy (&valbuf[2], ®buf[HARD_D_REGNUM * 2], 2); |
| 1136 | break; |
| 1137 | |
| 1138 | default: |
| 1139 | error ("bad size for return value"); |
| 1140 | } |
| 1141 | } |
| 1142 | |
| 1143 | /* Should call_function allocate stack space for a struct return? */ |
| 1144 | static int |
| 1145 | m68hc11_use_struct_convention (int gcc_p, struct type *type) |
| 1146 | { |
| 1147 | return (TYPE_CODE (type) == TYPE_CODE_STRUCT |
| 1148 | || TYPE_CODE (type) == TYPE_CODE_UNION |
| 1149 | || TYPE_LENGTH (type) > 4); |
| 1150 | } |
| 1151 | |
| 1152 | static int |
| 1153 | m68hc11_return_value_on_stack (struct type *type) |
| 1154 | { |
| 1155 | return TYPE_LENGTH (type) > 4; |
| 1156 | } |
| 1157 | |
| 1158 | /* Extract from an array REGBUF containing the (raw) register state |
| 1159 | the address in which a function should return its structure value, |
| 1160 | as a CORE_ADDR (or an expression that can be used as one). */ |
| 1161 | static CORE_ADDR |
| 1162 | m68hc11_extract_struct_value_address (char *regbuf) |
| 1163 | { |
| 1164 | return extract_address (®buf[HARD_D_REGNUM * 2], |
| 1165 | REGISTER_RAW_SIZE (HARD_D_REGNUM)); |
| 1166 | } |
| 1167 | |
| 1168 | /* Function: push_return_address (pc) |
| 1169 | Set up the return address for the inferior function call. |
| 1170 | Needed for targets where we don't actually execute a JSR/BSR instruction */ |
| 1171 | |
| 1172 | static CORE_ADDR |
| 1173 | m68hc11_push_return_address (CORE_ADDR pc, CORE_ADDR sp) |
| 1174 | { |
| 1175 | char valbuf[2]; |
| 1176 | |
| 1177 | pc = CALL_DUMMY_ADDRESS (); |
| 1178 | sp -= 2; |
| 1179 | store_unsigned_integer (valbuf, 2, pc); |
| 1180 | write_memory (sp + STACK_CORRECTION, valbuf, 2); |
| 1181 | return sp; |
| 1182 | } |
| 1183 | |
| 1184 | /* Test whether the ELF symbol corresponds to a function using rtc or |
| 1185 | rti to return. */ |
| 1186 | |
| 1187 | static void |
| 1188 | m68hc11_elf_make_msymbol_special (asymbol *sym, struct minimal_symbol *msym) |
| 1189 | { |
| 1190 | unsigned char flags; |
| 1191 | |
| 1192 | flags = ((elf_symbol_type *)sym)->internal_elf_sym.st_other; |
| 1193 | if (flags & STO_M68HC12_FAR) |
| 1194 | MSYMBOL_SET_RTC (msym); |
| 1195 | if (flags & STO_M68HC12_INTERRUPT) |
| 1196 | MSYMBOL_SET_RTI (msym); |
| 1197 | } |
| 1198 | |
| 1199 | static int |
| 1200 | gdb_print_insn_m68hc11 (bfd_vma memaddr, disassemble_info *info) |
| 1201 | { |
| 1202 | if (TARGET_ARCHITECTURE->arch == bfd_arch_m68hc11) |
| 1203 | return print_insn_m68hc11 (memaddr, info); |
| 1204 | else |
| 1205 | return print_insn_m68hc12 (memaddr, info); |
| 1206 | } |
| 1207 | |
| 1208 | static struct gdbarch * |
| 1209 | m68hc11_gdbarch_init (struct gdbarch_info info, |
| 1210 | struct gdbarch_list *arches) |
| 1211 | { |
| 1212 | static LONGEST m68hc11_call_dummy_words[] = |
| 1213 | {0}; |
| 1214 | struct gdbarch *gdbarch; |
| 1215 | struct gdbarch_tdep *tdep; |
| 1216 | int elf_flags; |
| 1217 | |
| 1218 | soft_reg_initialized = 0; |
| 1219 | |
| 1220 | /* Extract the elf_flags if available. */ |
| 1221 | if (info.abfd != NULL |
| 1222 | && bfd_get_flavour (info.abfd) == bfd_target_elf_flavour) |
| 1223 | elf_flags = elf_elfheader (info.abfd)->e_flags; |
| 1224 | else |
| 1225 | elf_flags = 0; |
| 1226 | |
| 1227 | /* try to find a pre-existing architecture */ |
| 1228 | for (arches = gdbarch_list_lookup_by_info (arches, &info); |
| 1229 | arches != NULL; |
| 1230 | arches = gdbarch_list_lookup_by_info (arches->next, &info)) |
| 1231 | { |
| 1232 | if (gdbarch_tdep (arches->gdbarch)->elf_flags != elf_flags) |
| 1233 | continue; |
| 1234 | |
| 1235 | return arches->gdbarch; |
| 1236 | } |
| 1237 | |
| 1238 | /* Need a new architecture. Fill in a target specific vector. */ |
| 1239 | tdep = (struct gdbarch_tdep *) xmalloc (sizeof (struct gdbarch_tdep)); |
| 1240 | gdbarch = gdbarch_alloc (&info, tdep); |
| 1241 | tdep->elf_flags = elf_flags; |
| 1242 | |
| 1243 | /* NOTE: cagney/2002-12-06: This can be deleted when this arch is |
| 1244 | ready to unwind the PC first (see frame.c:get_prev_frame()). */ |
| 1245 | set_gdbarch_deprecated_init_frame_pc (gdbarch, init_frame_pc_default); |
| 1246 | |
| 1247 | switch (info.bfd_arch_info->arch) |
| 1248 | { |
| 1249 | case bfd_arch_m68hc11: |
| 1250 | tdep->stack_correction = 1; |
| 1251 | tdep->use_page_register = 0; |
| 1252 | tdep->prologue = m6811_prologue; |
| 1253 | set_gdbarch_addr_bit (gdbarch, 16); |
| 1254 | set_gdbarch_num_pseudo_regs (gdbarch, M68HC11_NUM_PSEUDO_REGS); |
| 1255 | set_gdbarch_pc_regnum (gdbarch, HARD_PC_REGNUM); |
| 1256 | set_gdbarch_num_regs (gdbarch, M68HC11_NUM_REGS); |
| 1257 | break; |
| 1258 | |
| 1259 | case bfd_arch_m68hc12: |
| 1260 | tdep->stack_correction = 0; |
| 1261 | tdep->use_page_register = elf_flags & E_M68HC12_BANKS; |
| 1262 | tdep->prologue = m6812_prologue; |
| 1263 | set_gdbarch_addr_bit (gdbarch, elf_flags & E_M68HC12_BANKS ? 32 : 16); |
| 1264 | set_gdbarch_num_pseudo_regs (gdbarch, |
| 1265 | elf_flags & E_M68HC12_BANKS |
| 1266 | ? M68HC12_NUM_PSEUDO_REGS |
| 1267 | : M68HC11_NUM_PSEUDO_REGS); |
| 1268 | set_gdbarch_pc_regnum (gdbarch, elf_flags & E_M68HC12_BANKS |
| 1269 | ? M68HC12_HARD_PC_REGNUM : HARD_PC_REGNUM); |
| 1270 | set_gdbarch_num_regs (gdbarch, elf_flags & E_M68HC12_BANKS |
| 1271 | ? M68HC12_NUM_REGS : M68HC11_NUM_REGS); |
| 1272 | break; |
| 1273 | |
| 1274 | default: |
| 1275 | break; |
| 1276 | } |
| 1277 | |
| 1278 | /* Initially set everything according to the ABI. |
| 1279 | Use 16-bit integers since it will be the case for most |
| 1280 | programs. The size of these types should normally be set |
| 1281 | according to the dwarf2 debug information. */ |
| 1282 | set_gdbarch_short_bit (gdbarch, 16); |
| 1283 | set_gdbarch_int_bit (gdbarch, elf_flags & E_M68HC11_I32 ? 32 : 16); |
| 1284 | set_gdbarch_float_bit (gdbarch, 32); |
| 1285 | set_gdbarch_double_bit (gdbarch, elf_flags & E_M68HC11_F64 ? 64 : 32); |
| 1286 | set_gdbarch_long_double_bit (gdbarch, elf_flags & E_M68HC11_F64 ? 64 : 32); |
| 1287 | set_gdbarch_long_bit (gdbarch, 32); |
| 1288 | set_gdbarch_ptr_bit (gdbarch, 16); |
| 1289 | set_gdbarch_long_long_bit (gdbarch, 64); |
| 1290 | |
| 1291 | /* Set register info. */ |
| 1292 | set_gdbarch_fp0_regnum (gdbarch, -1); |
| 1293 | set_gdbarch_max_register_raw_size (gdbarch, 2); |
| 1294 | set_gdbarch_max_register_virtual_size (gdbarch, 2); |
| 1295 | set_gdbarch_frame_init_saved_regs (gdbarch, m68hc11_frame_init_saved_regs); |
| 1296 | set_gdbarch_frame_args_skip (gdbarch, 0); |
| 1297 | |
| 1298 | set_gdbarch_read_pc (gdbarch, generic_target_read_pc); |
| 1299 | set_gdbarch_write_pc (gdbarch, generic_target_write_pc); |
| 1300 | set_gdbarch_read_fp (gdbarch, generic_target_read_fp); |
| 1301 | set_gdbarch_read_sp (gdbarch, generic_target_read_sp); |
| 1302 | set_gdbarch_write_sp (gdbarch, generic_target_write_sp); |
| 1303 | |
| 1304 | set_gdbarch_sp_regnum (gdbarch, HARD_SP_REGNUM); |
| 1305 | set_gdbarch_fp_regnum (gdbarch, SOFT_FP_REGNUM); |
| 1306 | set_gdbarch_register_name (gdbarch, m68hc11_register_name); |
| 1307 | set_gdbarch_register_size (gdbarch, 2); |
| 1308 | set_gdbarch_register_bytes (gdbarch, M68HC11_ALL_REGS * 2); |
| 1309 | set_gdbarch_register_virtual_type (gdbarch, m68hc11_register_virtual_type); |
| 1310 | set_gdbarch_pseudo_register_read (gdbarch, m68hc11_pseudo_register_read); |
| 1311 | set_gdbarch_pseudo_register_write (gdbarch, m68hc11_pseudo_register_write); |
| 1312 | |
| 1313 | set_gdbarch_call_dummy_length (gdbarch, 0); |
| 1314 | set_gdbarch_call_dummy_address (gdbarch, m68hc11_call_dummy_address); |
| 1315 | set_gdbarch_call_dummy_breakpoint_offset_p (gdbarch, 1); /*???*/ |
| 1316 | set_gdbarch_call_dummy_breakpoint_offset (gdbarch, 0); |
| 1317 | set_gdbarch_call_dummy_start_offset (gdbarch, 0); |
| 1318 | set_gdbarch_call_dummy_words (gdbarch, m68hc11_call_dummy_words); |
| 1319 | set_gdbarch_sizeof_call_dummy_words (gdbarch, |
| 1320 | sizeof (m68hc11_call_dummy_words)); |
| 1321 | set_gdbarch_call_dummy_p (gdbarch, 1); |
| 1322 | set_gdbarch_call_dummy_stack_adjust_p (gdbarch, 0); |
| 1323 | set_gdbarch_get_saved_register (gdbarch, deprecated_generic_get_saved_register); |
| 1324 | set_gdbarch_fix_call_dummy (gdbarch, generic_fix_call_dummy); |
| 1325 | set_gdbarch_deprecated_extract_return_value (gdbarch, m68hc11_extract_return_value); |
| 1326 | set_gdbarch_push_arguments (gdbarch, m68hc11_push_arguments); |
| 1327 | set_gdbarch_push_dummy_frame (gdbarch, generic_push_dummy_frame); |
| 1328 | set_gdbarch_push_return_address (gdbarch, m68hc11_push_return_address); |
| 1329 | set_gdbarch_return_value_on_stack (gdbarch, m68hc11_return_value_on_stack); |
| 1330 | |
| 1331 | set_gdbarch_store_struct_return (gdbarch, m68hc11_store_struct_return); |
| 1332 | set_gdbarch_deprecated_store_return_value (gdbarch, m68hc11_store_return_value); |
| 1333 | set_gdbarch_deprecated_extract_struct_value_address (gdbarch, m68hc11_extract_struct_value_address); |
| 1334 | set_gdbarch_register_convertible (gdbarch, generic_register_convertible_not); |
| 1335 | |
| 1336 | |
| 1337 | set_gdbarch_frame_chain (gdbarch, m68hc11_frame_chain); |
| 1338 | set_gdbarch_frame_saved_pc (gdbarch, m68hc11_frame_saved_pc); |
| 1339 | set_gdbarch_frame_args_address (gdbarch, m68hc11_frame_args_address); |
| 1340 | set_gdbarch_frame_locals_address (gdbarch, m68hc11_frame_locals_address); |
| 1341 | set_gdbarch_saved_pc_after_call (gdbarch, m68hc11_saved_pc_after_call); |
| 1342 | set_gdbarch_frame_num_args (gdbarch, frame_num_args_unknown); |
| 1343 | |
| 1344 | set_gdbarch_get_saved_register (gdbarch, deprecated_generic_get_saved_register); |
| 1345 | |
| 1346 | set_gdbarch_store_struct_return (gdbarch, m68hc11_store_struct_return); |
| 1347 | set_gdbarch_deprecated_store_return_value (gdbarch, m68hc11_store_return_value); |
| 1348 | set_gdbarch_deprecated_extract_struct_value_address |
| 1349 | (gdbarch, m68hc11_extract_struct_value_address); |
| 1350 | set_gdbarch_use_struct_convention (gdbarch, m68hc11_use_struct_convention); |
| 1351 | set_gdbarch_init_extra_frame_info (gdbarch, m68hc11_init_extra_frame_info); |
| 1352 | set_gdbarch_pop_frame (gdbarch, m68hc11_pop_frame); |
| 1353 | set_gdbarch_skip_prologue (gdbarch, m68hc11_skip_prologue); |
| 1354 | set_gdbarch_inner_than (gdbarch, core_addr_lessthan); |
| 1355 | set_gdbarch_decr_pc_after_break (gdbarch, 0); |
| 1356 | set_gdbarch_function_start_offset (gdbarch, 0); |
| 1357 | set_gdbarch_breakpoint_from_pc (gdbarch, m68hc11_breakpoint_from_pc); |
| 1358 | set_gdbarch_stack_align (gdbarch, m68hc11_stack_align); |
| 1359 | set_gdbarch_print_insn (gdbarch, gdb_print_insn_m68hc11); |
| 1360 | |
| 1361 | /* Minsymbol frobbing. */ |
| 1362 | set_gdbarch_elf_make_msymbol_special (gdbarch, |
| 1363 | m68hc11_elf_make_msymbol_special); |
| 1364 | |
| 1365 | set_gdbarch_believe_pcc_promotion (gdbarch, 1); |
| 1366 | |
| 1367 | return gdbarch; |
| 1368 | } |
| 1369 | |
| 1370 | void |
| 1371 | _initialize_m68hc11_tdep (void) |
| 1372 | { |
| 1373 | register_gdbarch_init (bfd_arch_m68hc11, m68hc11_gdbarch_init); |
| 1374 | register_gdbarch_init (bfd_arch_m68hc12, m68hc11_gdbarch_init); |
| 1375 | |
| 1376 | add_com ("regs", class_vars, show_regs, "Print all registers"); |
| 1377 | } |
| 1378 | |