| 1 | /* Target-dependent code for the Matsushita MN10300 for GDB, the GNU debugger. |
| 2 | |
| 3 | Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, |
| 4 | 2007, 2008 Free Software Foundation, Inc. |
| 5 | |
| 6 | This file is part of GDB. |
| 7 | |
| 8 | This program is free software; you can redistribute it and/or modify |
| 9 | it under the terms of the GNU General Public License as published by |
| 10 | the Free Software Foundation; either version 3 of the License, or |
| 11 | (at your option) any later version. |
| 12 | |
| 13 | This program is distributed in the hope that it will be useful, |
| 14 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | GNU General Public License for more details. |
| 17 | |
| 18 | You should have received a copy of the GNU General Public License |
| 19 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 20 | |
| 21 | #include "defs.h" |
| 22 | #include "arch-utils.h" |
| 23 | #include "dis-asm.h" |
| 24 | #include "gdbtypes.h" |
| 25 | #include "regcache.h" |
| 26 | #include "gdb_string.h" |
| 27 | #include "gdb_assert.h" |
| 28 | #include "gdbcore.h" /* for write_memory_unsigned_integer */ |
| 29 | #include "value.h" |
| 30 | #include "gdbtypes.h" |
| 31 | #include "frame.h" |
| 32 | #include "frame-unwind.h" |
| 33 | #include "frame-base.h" |
| 34 | #include "trad-frame.h" |
| 35 | #include "symtab.h" |
| 36 | #include "dwarf2-frame.h" |
| 37 | #include "osabi.h" |
| 38 | #include "infcall.h" |
| 39 | #include "target.h" |
| 40 | |
| 41 | #include "mn10300-tdep.h" |
| 42 | |
| 43 | /* Forward decl. */ |
| 44 | extern struct trad_frame_cache *mn10300_frame_unwind_cache (struct frame_info*, |
| 45 | void **); |
| 46 | |
| 47 | /* Compute the alignment required by a type. */ |
| 48 | |
| 49 | static int |
| 50 | mn10300_type_align (struct type *type) |
| 51 | { |
| 52 | int i, align = 1; |
| 53 | |
| 54 | switch (TYPE_CODE (type)) |
| 55 | { |
| 56 | case TYPE_CODE_INT: |
| 57 | case TYPE_CODE_ENUM: |
| 58 | case TYPE_CODE_SET: |
| 59 | case TYPE_CODE_RANGE: |
| 60 | case TYPE_CODE_CHAR: |
| 61 | case TYPE_CODE_BOOL: |
| 62 | case TYPE_CODE_FLT: |
| 63 | case TYPE_CODE_PTR: |
| 64 | case TYPE_CODE_REF: |
| 65 | return TYPE_LENGTH (type); |
| 66 | |
| 67 | case TYPE_CODE_COMPLEX: |
| 68 | return TYPE_LENGTH (type) / 2; |
| 69 | |
| 70 | case TYPE_CODE_STRUCT: |
| 71 | case TYPE_CODE_UNION: |
| 72 | for (i = 0; i < TYPE_NFIELDS (type); i++) |
| 73 | { |
| 74 | int falign = mn10300_type_align (TYPE_FIELD_TYPE (type, i)); |
| 75 | while (align < falign) |
| 76 | align <<= 1; |
| 77 | } |
| 78 | return align; |
| 79 | |
| 80 | case TYPE_CODE_ARRAY: |
| 81 | /* HACK! Structures containing arrays, even small ones, are not |
| 82 | elligible for returning in registers. */ |
| 83 | return 256; |
| 84 | |
| 85 | case TYPE_CODE_TYPEDEF: |
| 86 | return mn10300_type_align (check_typedef (type)); |
| 87 | |
| 88 | default: |
| 89 | internal_error (__FILE__, __LINE__, _("bad switch")); |
| 90 | } |
| 91 | } |
| 92 | |
| 93 | /* Should call_function allocate stack space for a struct return? */ |
| 94 | static int |
| 95 | mn10300_use_struct_convention (struct type *type) |
| 96 | { |
| 97 | /* Structures bigger than a pair of words can't be returned in |
| 98 | registers. */ |
| 99 | if (TYPE_LENGTH (type) > 8) |
| 100 | return 1; |
| 101 | |
| 102 | switch (TYPE_CODE (type)) |
| 103 | { |
| 104 | case TYPE_CODE_STRUCT: |
| 105 | case TYPE_CODE_UNION: |
| 106 | /* Structures with a single field are handled as the field |
| 107 | itself. */ |
| 108 | if (TYPE_NFIELDS (type) == 1) |
| 109 | return mn10300_use_struct_convention (TYPE_FIELD_TYPE (type, 0)); |
| 110 | |
| 111 | /* Structures with word or double-word size are passed in memory, as |
| 112 | long as they require at least word alignment. */ |
| 113 | if (mn10300_type_align (type) >= 4) |
| 114 | return 0; |
| 115 | |
| 116 | return 1; |
| 117 | |
| 118 | /* Arrays are addressable, so they're never returned in |
| 119 | registers. This condition can only hold when the array is |
| 120 | the only field of a struct or union. */ |
| 121 | case TYPE_CODE_ARRAY: |
| 122 | return 1; |
| 123 | |
| 124 | case TYPE_CODE_TYPEDEF: |
| 125 | return mn10300_use_struct_convention (check_typedef (type)); |
| 126 | |
| 127 | default: |
| 128 | return 0; |
| 129 | } |
| 130 | } |
| 131 | |
| 132 | static void |
| 133 | mn10300_store_return_value (struct gdbarch *gdbarch, struct type *type, |
| 134 | struct regcache *regcache, const void *valbuf) |
| 135 | { |
| 136 | int len = TYPE_LENGTH (type); |
| 137 | int reg, regsz; |
| 138 | |
| 139 | if (TYPE_CODE (type) == TYPE_CODE_PTR) |
| 140 | reg = 4; |
| 141 | else |
| 142 | reg = 0; |
| 143 | |
| 144 | regsz = register_size (gdbarch, reg); |
| 145 | |
| 146 | if (len <= regsz) |
| 147 | regcache_raw_write_part (regcache, reg, 0, len, valbuf); |
| 148 | else if (len <= 2 * regsz) |
| 149 | { |
| 150 | regcache_raw_write (regcache, reg, valbuf); |
| 151 | gdb_assert (regsz == register_size (gdbarch, reg + 1)); |
| 152 | regcache_raw_write_part (regcache, reg+1, 0, |
| 153 | len - regsz, (char *) valbuf + regsz); |
| 154 | } |
| 155 | else |
| 156 | internal_error (__FILE__, __LINE__, |
| 157 | _("Cannot store return value %d bytes long."), len); |
| 158 | } |
| 159 | |
| 160 | static void |
| 161 | mn10300_extract_return_value (struct gdbarch *gdbarch, struct type *type, |
| 162 | struct regcache *regcache, void *valbuf) |
| 163 | { |
| 164 | char buf[MAX_REGISTER_SIZE]; |
| 165 | int len = TYPE_LENGTH (type); |
| 166 | int reg, regsz; |
| 167 | |
| 168 | if (TYPE_CODE (type) == TYPE_CODE_PTR) |
| 169 | reg = 4; |
| 170 | else |
| 171 | reg = 0; |
| 172 | |
| 173 | regsz = register_size (gdbarch, reg); |
| 174 | if (len <= regsz) |
| 175 | { |
| 176 | regcache_raw_read (regcache, reg, buf); |
| 177 | memcpy (valbuf, buf, len); |
| 178 | } |
| 179 | else if (len <= 2 * regsz) |
| 180 | { |
| 181 | regcache_raw_read (regcache, reg, buf); |
| 182 | memcpy (valbuf, buf, regsz); |
| 183 | gdb_assert (regsz == register_size (gdbarch, reg + 1)); |
| 184 | regcache_raw_read (regcache, reg + 1, buf); |
| 185 | memcpy ((char *) valbuf + regsz, buf, len - regsz); |
| 186 | } |
| 187 | else |
| 188 | internal_error (__FILE__, __LINE__, |
| 189 | _("Cannot extract return value %d bytes long."), len); |
| 190 | } |
| 191 | |
| 192 | /* Determine, for architecture GDBARCH, how a return value of TYPE |
| 193 | should be returned. If it is supposed to be returned in registers, |
| 194 | and READBUF is non-zero, read the appropriate value from REGCACHE, |
| 195 | and copy it into READBUF. If WRITEBUF is non-zero, write the value |
| 196 | from WRITEBUF into REGCACHE. */ |
| 197 | |
| 198 | static enum return_value_convention |
| 199 | mn10300_return_value (struct gdbarch *gdbarch, struct type *func_type, |
| 200 | struct type *type, struct regcache *regcache, |
| 201 | gdb_byte *readbuf, const gdb_byte *writebuf) |
| 202 | { |
| 203 | if (mn10300_use_struct_convention (type)) |
| 204 | return RETURN_VALUE_STRUCT_CONVENTION; |
| 205 | |
| 206 | if (readbuf) |
| 207 | mn10300_extract_return_value (gdbarch, type, regcache, readbuf); |
| 208 | if (writebuf) |
| 209 | mn10300_store_return_value (gdbarch, type, regcache, writebuf); |
| 210 | |
| 211 | return RETURN_VALUE_REGISTER_CONVENTION; |
| 212 | } |
| 213 | |
| 214 | static char * |
| 215 | register_name (int reg, char **regs, long sizeof_regs) |
| 216 | { |
| 217 | if (reg < 0 || reg >= sizeof_regs / sizeof (regs[0])) |
| 218 | return NULL; |
| 219 | else |
| 220 | return regs[reg]; |
| 221 | } |
| 222 | |
| 223 | static const char * |
| 224 | mn10300_generic_register_name (struct gdbarch *gdbarch, int reg) |
| 225 | { |
| 226 | static char *regs[] = |
| 227 | { "d0", "d1", "d2", "d3", "a0", "a1", "a2", "a3", |
| 228 | "sp", "pc", "mdr", "psw", "lir", "lar", "", "", |
| 229 | "", "", "", "", "", "", "", "", |
| 230 | "", "", "", "", "", "", "", "fp" |
| 231 | }; |
| 232 | return register_name (reg, regs, sizeof regs); |
| 233 | } |
| 234 | |
| 235 | |
| 236 | static const char * |
| 237 | am33_register_name (struct gdbarch *gdbarch, int reg) |
| 238 | { |
| 239 | static char *regs[] = |
| 240 | { "d0", "d1", "d2", "d3", "a0", "a1", "a2", "a3", |
| 241 | "sp", "pc", "mdr", "psw", "lir", "lar", "", |
| 242 | "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", |
| 243 | "ssp", "msp", "usp", "mcrh", "mcrl", "mcvf", "", "", "" |
| 244 | }; |
| 245 | return register_name (reg, regs, sizeof regs); |
| 246 | } |
| 247 | |
| 248 | static const char * |
| 249 | am33_2_register_name (struct gdbarch *gdbarch, int reg) |
| 250 | { |
| 251 | static char *regs[] = |
| 252 | { |
| 253 | "d0", "d1", "d2", "d3", "a0", "a1", "a2", "a3", |
| 254 | "sp", "pc", "mdr", "psw", "lir", "lar", "mdrq", "r0", |
| 255 | "r1", "r2", "r3", "r4", "r5", "r6", "r7", "ssp", |
| 256 | "msp", "usp", "mcrh", "mcrl", "mcvf", "fpcr", "", "", |
| 257 | "fs0", "fs1", "fs2", "fs3", "fs4", "fs5", "fs6", "fs7", |
| 258 | "fs8", "fs9", "fs10", "fs11", "fs12", "fs13", "fs14", "fs15", |
| 259 | "fs16", "fs17", "fs18", "fs19", "fs20", "fs21", "fs22", "fs23", |
| 260 | "fs24", "fs25", "fs26", "fs27", "fs28", "fs29", "fs30", "fs31" |
| 261 | }; |
| 262 | return register_name (reg, regs, sizeof regs); |
| 263 | } |
| 264 | |
| 265 | static struct type * |
| 266 | mn10300_register_type (struct gdbarch *gdbarch, int reg) |
| 267 | { |
| 268 | return builtin_type_int; |
| 269 | } |
| 270 | |
| 271 | static CORE_ADDR |
| 272 | mn10300_read_pc (struct regcache *regcache) |
| 273 | { |
| 274 | ULONGEST val; |
| 275 | regcache_cooked_read_unsigned (regcache, E_PC_REGNUM, &val); |
| 276 | return val; |
| 277 | } |
| 278 | |
| 279 | static void |
| 280 | mn10300_write_pc (struct regcache *regcache, CORE_ADDR val) |
| 281 | { |
| 282 | regcache_cooked_write_unsigned (regcache, E_PC_REGNUM, val); |
| 283 | } |
| 284 | |
| 285 | /* The breakpoint instruction must be the same size as the smallest |
| 286 | instruction in the instruction set. |
| 287 | |
| 288 | The Matsushita mn10x00 processors have single byte instructions |
| 289 | so we need a single byte breakpoint. Matsushita hasn't defined |
| 290 | one, so we defined it ourselves. */ |
| 291 | |
| 292 | const static unsigned char * |
| 293 | mn10300_breakpoint_from_pc (struct gdbarch *gdbarch, CORE_ADDR *bp_addr, |
| 294 | int *bp_size) |
| 295 | { |
| 296 | static char breakpoint[] = {0xff}; |
| 297 | *bp_size = 1; |
| 298 | return breakpoint; |
| 299 | } |
| 300 | |
| 301 | /* Set offsets of saved registers. |
| 302 | This is a helper function for mn10300_analyze_prologue. */ |
| 303 | |
| 304 | static void |
| 305 | set_reg_offsets (struct frame_info *fi, |
| 306 | void **this_cache, |
| 307 | int movm_args, |
| 308 | int fpregmask, |
| 309 | int stack_extra_size, |
| 310 | int frame_in_fp) |
| 311 | { |
| 312 | struct gdbarch *gdbarch; |
| 313 | struct trad_frame_cache *cache; |
| 314 | int offset = 0; |
| 315 | CORE_ADDR base; |
| 316 | |
| 317 | if (fi == NULL || this_cache == NULL) |
| 318 | return; |
| 319 | |
| 320 | cache = mn10300_frame_unwind_cache (fi, this_cache); |
| 321 | if (cache == NULL) |
| 322 | return; |
| 323 | gdbarch = get_frame_arch (fi); |
| 324 | |
| 325 | if (frame_in_fp) |
| 326 | { |
| 327 | base = frame_unwind_register_unsigned (fi, E_A3_REGNUM); |
| 328 | } |
| 329 | else |
| 330 | { |
| 331 | base = frame_unwind_register_unsigned (fi, E_SP_REGNUM) |
| 332 | + stack_extra_size; |
| 333 | } |
| 334 | |
| 335 | trad_frame_set_this_base (cache, base); |
| 336 | |
| 337 | if (AM33_MODE (gdbarch) == 2) |
| 338 | { |
| 339 | /* If bit N is set in fpregmask, fsN is saved on the stack. |
| 340 | The floating point registers are saved in ascending order. |
| 341 | For example: fs16 <- Frame Pointer |
| 342 | fs17 Frame Pointer + 4 */ |
| 343 | if (fpregmask != 0) |
| 344 | { |
| 345 | int i; |
| 346 | for (i = 0; i < 32; i++) |
| 347 | { |
| 348 | if (fpregmask & (1 << i)) |
| 349 | { |
| 350 | trad_frame_set_reg_addr (cache, E_FS0_REGNUM + i, |
| 351 | base + offset); |
| 352 | offset += 4; |
| 353 | } |
| 354 | } |
| 355 | } |
| 356 | } |
| 357 | |
| 358 | |
| 359 | if (movm_args & movm_other_bit) |
| 360 | { |
| 361 | /* The `other' bit leaves a blank area of four bytes at the |
| 362 | beginning of its block of saved registers, making it 32 bytes |
| 363 | long in total. */ |
| 364 | trad_frame_set_reg_addr (cache, E_LAR_REGNUM, base + offset + 4); |
| 365 | trad_frame_set_reg_addr (cache, E_LIR_REGNUM, base + offset + 8); |
| 366 | trad_frame_set_reg_addr (cache, E_MDR_REGNUM, base + offset + 12); |
| 367 | trad_frame_set_reg_addr (cache, E_A0_REGNUM + 1, base + offset + 16); |
| 368 | trad_frame_set_reg_addr (cache, E_A0_REGNUM, base + offset + 20); |
| 369 | trad_frame_set_reg_addr (cache, E_D0_REGNUM + 1, base + offset + 24); |
| 370 | trad_frame_set_reg_addr (cache, E_D0_REGNUM, base + offset + 28); |
| 371 | offset += 32; |
| 372 | } |
| 373 | |
| 374 | if (movm_args & movm_a3_bit) |
| 375 | { |
| 376 | trad_frame_set_reg_addr (cache, E_A3_REGNUM, base + offset); |
| 377 | offset += 4; |
| 378 | } |
| 379 | if (movm_args & movm_a2_bit) |
| 380 | { |
| 381 | trad_frame_set_reg_addr (cache, E_A2_REGNUM, base + offset); |
| 382 | offset += 4; |
| 383 | } |
| 384 | if (movm_args & movm_d3_bit) |
| 385 | { |
| 386 | trad_frame_set_reg_addr (cache, E_D3_REGNUM, base + offset); |
| 387 | offset += 4; |
| 388 | } |
| 389 | if (movm_args & movm_d2_bit) |
| 390 | { |
| 391 | trad_frame_set_reg_addr (cache, E_D2_REGNUM, base + offset); |
| 392 | offset += 4; |
| 393 | } |
| 394 | if (AM33_MODE (gdbarch)) |
| 395 | { |
| 396 | if (movm_args & movm_exother_bit) |
| 397 | { |
| 398 | trad_frame_set_reg_addr (cache, E_MCVF_REGNUM, base + offset); |
| 399 | trad_frame_set_reg_addr (cache, E_MCRL_REGNUM, base + offset + 4); |
| 400 | trad_frame_set_reg_addr (cache, E_MCRH_REGNUM, base + offset + 8); |
| 401 | trad_frame_set_reg_addr (cache, E_MDRQ_REGNUM, base + offset + 12); |
| 402 | trad_frame_set_reg_addr (cache, E_E1_REGNUM, base + offset + 16); |
| 403 | trad_frame_set_reg_addr (cache, E_E0_REGNUM, base + offset + 20); |
| 404 | offset += 24; |
| 405 | } |
| 406 | if (movm_args & movm_exreg1_bit) |
| 407 | { |
| 408 | trad_frame_set_reg_addr (cache, E_E7_REGNUM, base + offset); |
| 409 | trad_frame_set_reg_addr (cache, E_E6_REGNUM, base + offset + 4); |
| 410 | trad_frame_set_reg_addr (cache, E_E5_REGNUM, base + offset + 8); |
| 411 | trad_frame_set_reg_addr (cache, E_E4_REGNUM, base + offset + 12); |
| 412 | offset += 16; |
| 413 | } |
| 414 | if (movm_args & movm_exreg0_bit) |
| 415 | { |
| 416 | trad_frame_set_reg_addr (cache, E_E3_REGNUM, base + offset); |
| 417 | trad_frame_set_reg_addr (cache, E_E2_REGNUM, base + offset + 4); |
| 418 | offset += 8; |
| 419 | } |
| 420 | } |
| 421 | /* The last (or first) thing on the stack will be the PC. */ |
| 422 | trad_frame_set_reg_addr (cache, E_PC_REGNUM, base + offset); |
| 423 | /* Save the SP in the 'traditional' way. |
| 424 | This will be the same location where the PC is saved. */ |
| 425 | trad_frame_set_reg_value (cache, E_SP_REGNUM, base + offset); |
| 426 | } |
| 427 | |
| 428 | /* The main purpose of this file is dealing with prologues to extract |
| 429 | information about stack frames and saved registers. |
| 430 | |
| 431 | In gcc/config/mn13000/mn10300.c, the expand_prologue prologue |
| 432 | function is pretty readable, and has a nice explanation of how the |
| 433 | prologue is generated. The prologues generated by that code will |
| 434 | have the following form (NOTE: the current code doesn't handle all |
| 435 | this!): |
| 436 | |
| 437 | + If this is an old-style varargs function, then its arguments |
| 438 | need to be flushed back to the stack: |
| 439 | |
| 440 | mov d0,(4,sp) |
| 441 | mov d1,(4,sp) |
| 442 | |
| 443 | + If we use any of the callee-saved registers, save them now. |
| 444 | |
| 445 | movm [some callee-saved registers],(sp) |
| 446 | |
| 447 | + If we have any floating-point registers to save: |
| 448 | |
| 449 | - Decrement the stack pointer to reserve space for the registers. |
| 450 | If the function doesn't need a frame pointer, we may combine |
| 451 | this with the adjustment that reserves space for the frame. |
| 452 | |
| 453 | add -SIZE, sp |
| 454 | |
| 455 | - Save the floating-point registers. We have two possible |
| 456 | strategies: |
| 457 | |
| 458 | . Save them at fixed offset from the SP: |
| 459 | |
| 460 | fmov fsN,(OFFSETN,sp) |
| 461 | fmov fsM,(OFFSETM,sp) |
| 462 | ... |
| 463 | |
| 464 | Note that, if OFFSETN happens to be zero, you'll get the |
| 465 | different opcode: fmov fsN,(sp) |
| 466 | |
| 467 | . Or, set a0 to the start of the save area, and then use |
| 468 | post-increment addressing to save the FP registers. |
| 469 | |
| 470 | mov sp, a0 |
| 471 | add SIZE, a0 |
| 472 | fmov fsN,(a0+) |
| 473 | fmov fsM,(a0+) |
| 474 | ... |
| 475 | |
| 476 | + If the function needs a frame pointer, we set it here. |
| 477 | |
| 478 | mov sp, a3 |
| 479 | |
| 480 | + Now we reserve space for the stack frame proper. This could be |
| 481 | merged into the `add -SIZE, sp' instruction for FP saves up |
| 482 | above, unless we needed to set the frame pointer in the previous |
| 483 | step, or the frame is so large that allocating the whole thing at |
| 484 | once would put the FP register save slots out of reach of the |
| 485 | addressing mode (128 bytes). |
| 486 | |
| 487 | add -SIZE, sp |
| 488 | |
| 489 | One day we might keep the stack pointer constant, that won't |
| 490 | change the code for prologues, but it will make the frame |
| 491 | pointerless case much more common. */ |
| 492 | |
| 493 | /* Analyze the prologue to determine where registers are saved, |
| 494 | the end of the prologue, etc etc. Return the end of the prologue |
| 495 | scanned. |
| 496 | |
| 497 | We store into FI (if non-null) several tidbits of information: |
| 498 | |
| 499 | * stack_size -- size of this stack frame. Note that if we stop in |
| 500 | certain parts of the prologue/epilogue we may claim the size of the |
| 501 | current frame is zero. This happens when the current frame has |
| 502 | not been allocated yet or has already been deallocated. |
| 503 | |
| 504 | * fsr -- Addresses of registers saved in the stack by this frame. |
| 505 | |
| 506 | * status -- A (relatively) generic status indicator. It's a bitmask |
| 507 | with the following bits: |
| 508 | |
| 509 | MY_FRAME_IN_SP: The base of the current frame is actually in |
| 510 | the stack pointer. This can happen for frame pointerless |
| 511 | functions, or cases where we're stopped in the prologue/epilogue |
| 512 | itself. For these cases mn10300_analyze_prologue will need up |
| 513 | update fi->frame before returning or analyzing the register |
| 514 | save instructions. |
| 515 | |
| 516 | MY_FRAME_IN_FP: The base of the current frame is in the |
| 517 | frame pointer register ($a3). |
| 518 | |
| 519 | NO_MORE_FRAMES: Set this if the current frame is "start" or |
| 520 | if the first instruction looks like mov <imm>,sp. This tells |
| 521 | frame chain to not bother trying to unwind past this frame. */ |
| 522 | |
| 523 | static CORE_ADDR |
| 524 | mn10300_analyze_prologue (struct gdbarch *gdbarch, struct frame_info *fi, |
| 525 | void **this_cache, |
| 526 | CORE_ADDR pc) |
| 527 | { |
| 528 | CORE_ADDR func_addr, func_end, addr, stop; |
| 529 | long stack_extra_size = 0; |
| 530 | int imm_size; |
| 531 | unsigned char buf[4]; |
| 532 | int status; |
| 533 | int movm_args = 0; |
| 534 | int fpregmask = 0; |
| 535 | char *name; |
| 536 | int frame_in_fp = 0; |
| 537 | |
| 538 | /* Use the PC in the frame if it's provided to look up the |
| 539 | start of this function. |
| 540 | |
| 541 | Note: kevinb/2003-07-16: We used to do the following here: |
| 542 | pc = (fi ? get_frame_pc (fi) : pc); |
| 543 | But this is (now) badly broken when called from analyze_dummy_frame(). |
| 544 | */ |
| 545 | if (fi) |
| 546 | { |
| 547 | pc = (pc ? pc : get_frame_pc (fi)); |
| 548 | } |
| 549 | |
| 550 | /* Find the start of this function. */ |
| 551 | status = find_pc_partial_function (pc, &name, &func_addr, &func_end); |
| 552 | |
| 553 | /* Do nothing if we couldn't find the start of this function |
| 554 | |
| 555 | MVS: comment went on to say "or if we're stopped at the first |
| 556 | instruction in the prologue" -- but code doesn't reflect that, |
| 557 | and I don't want to do that anyway. */ |
| 558 | if (status == 0) |
| 559 | { |
| 560 | addr = pc; |
| 561 | goto finish_prologue; |
| 562 | } |
| 563 | |
| 564 | /* If we're in start, then give up. */ |
| 565 | if (strcmp (name, "start") == 0) |
| 566 | { |
| 567 | addr = pc; |
| 568 | goto finish_prologue; |
| 569 | } |
| 570 | |
| 571 | /* Figure out where to stop scanning. */ |
| 572 | stop = fi ? pc : func_end; |
| 573 | |
| 574 | /* Don't walk off the end of the function. */ |
| 575 | stop = stop > func_end ? func_end : stop; |
| 576 | |
| 577 | /* Start scanning on the first instruction of this function. */ |
| 578 | addr = func_addr; |
| 579 | |
| 580 | /* Suck in two bytes. */ |
| 581 | if (addr + 2 > stop || !safe_frame_unwind_memory (fi, addr, buf, 2)) |
| 582 | goto finish_prologue; |
| 583 | |
| 584 | /* First see if this insn sets the stack pointer from a register; if |
| 585 | so, it's probably the initialization of the stack pointer in _start, |
| 586 | so mark this as the bottom-most frame. */ |
| 587 | if (buf[0] == 0xf2 && (buf[1] & 0xf3) == 0xf0) |
| 588 | { |
| 589 | goto finish_prologue; |
| 590 | } |
| 591 | |
| 592 | /* Now look for movm [regs],sp, which saves the callee saved registers. |
| 593 | |
| 594 | At this time we don't know if fi->frame is valid, so we only note |
| 595 | that we encountered a movm instruction. Later, we'll set the entries |
| 596 | in fsr.regs as needed. */ |
| 597 | if (buf[0] == 0xcf) |
| 598 | { |
| 599 | /* Extract the register list for the movm instruction. */ |
| 600 | movm_args = buf[1]; |
| 601 | |
| 602 | addr += 2; |
| 603 | |
| 604 | /* Quit now if we're beyond the stop point. */ |
| 605 | if (addr >= stop) |
| 606 | goto finish_prologue; |
| 607 | |
| 608 | /* Get the next two bytes so the prologue scan can continue. */ |
| 609 | if (!safe_frame_unwind_memory (fi, addr, buf, 2)) |
| 610 | goto finish_prologue; |
| 611 | } |
| 612 | |
| 613 | /* Check for "mov pc, a2", an instruction found in optimized, position |
| 614 | independent code. Skip it if found. */ |
| 615 | if (buf[0] == 0xf0 && buf[1] == 0x2e) |
| 616 | { |
| 617 | addr += 2; |
| 618 | |
| 619 | /* Quit now if we're beyond the stop point. */ |
| 620 | if (addr >= stop) |
| 621 | goto finish_prologue; |
| 622 | |
| 623 | /* Get the next two bytes so the prologue scan can continue. */ |
| 624 | status = target_read_memory (addr, buf, 2); |
| 625 | if (status != 0) |
| 626 | goto finish_prologue; |
| 627 | } |
| 628 | |
| 629 | if (AM33_MODE (gdbarch) == 2) |
| 630 | { |
| 631 | /* Determine if any floating point registers are to be saved. |
| 632 | Look for one of the following three prologue formats: |
| 633 | |
| 634 | [movm [regs],(sp)] [movm [regs],(sp)] [movm [regs],(sp)] |
| 635 | |
| 636 | add -SIZE,sp add -SIZE,sp add -SIZE,sp |
| 637 | fmov fs#,(sp) mov sp,a0/a1 mov sp,a0/a1 |
| 638 | fmov fs#,(#,sp) fmov fs#,(a0/a1+) add SIZE2,a0/a1 |
| 639 | ... ... fmov fs#,(a0/a1+) |
| 640 | ... ... ... |
| 641 | fmov fs#,(#,sp) fmov fs#,(a0/a1+) fmov fs#,(a0/a1+) |
| 642 | |
| 643 | [mov sp,a3] [mov sp,a3] |
| 644 | [add -SIZE2,sp] [add -SIZE2,sp] */ |
| 645 | |
| 646 | /* Remember the address at which we started in the event that we |
| 647 | don't ultimately find an fmov instruction. Once we're certain |
| 648 | that we matched one of the above patterns, we'll set |
| 649 | ``restore_addr'' to the appropriate value. Note: At one time |
| 650 | in the past, this code attempted to not adjust ``addr'' until |
| 651 | there was a fair degree of certainty that the pattern would be |
| 652 | matched. However, that code did not wait until an fmov instruction |
| 653 | was actually encountered. As a consequence, ``addr'' would |
| 654 | sometimes be advanced even when no fmov instructions were found. */ |
| 655 | CORE_ADDR restore_addr = addr; |
| 656 | int fmov_found = 0; |
| 657 | |
| 658 | /* First, look for add -SIZE,sp (i.e. add imm8,sp (0xf8feXX) |
| 659 | or add imm16,sp (0xfafeXXXX) |
| 660 | or add imm32,sp (0xfcfeXXXXXXXX)) */ |
| 661 | imm_size = 0; |
| 662 | if (buf[0] == 0xf8 && buf[1] == 0xfe) |
| 663 | imm_size = 1; |
| 664 | else if (buf[0] == 0xfa && buf[1] == 0xfe) |
| 665 | imm_size = 2; |
| 666 | else if (buf[0] == 0xfc && buf[1] == 0xfe) |
| 667 | imm_size = 4; |
| 668 | if (imm_size != 0) |
| 669 | { |
| 670 | /* An "add -#,sp" instruction has been found. "addr + 2 + imm_size" |
| 671 | is the address of the next instruction. Don't modify "addr" until |
| 672 | the next "floating point prologue" instruction is found. If this |
| 673 | is not a prologue that saves floating point registers we need to |
| 674 | be able to back out of this bit of code and continue with the |
| 675 | prologue analysis. */ |
| 676 | if (addr + 2 + imm_size < stop) |
| 677 | { |
| 678 | if (!safe_frame_unwind_memory (fi, addr + 2 + imm_size, buf, 3)) |
| 679 | goto finish_prologue; |
| 680 | if ((buf[0] & 0xfc) == 0x3c) |
| 681 | { |
| 682 | /* Occasionally, especially with C++ code, the "fmov" |
| 683 | instructions will be preceded by "mov sp,aN" |
| 684 | (aN => a0, a1, a2, or a3). |
| 685 | |
| 686 | This is a one byte instruction: mov sp,aN = 0011 11XX |
| 687 | where XX is the register number. |
| 688 | |
| 689 | Skip this instruction by incrementing addr. The "fmov" |
| 690 | instructions will have the form "fmov fs#,(aN+)" in this |
| 691 | case, but that will not necessitate a change in the |
| 692 | "fmov" parsing logic below. */ |
| 693 | |
| 694 | addr++; |
| 695 | |
| 696 | if ((buf[1] & 0xfc) == 0x20) |
| 697 | { |
| 698 | /* Occasionally, especially with C++ code compiled with |
| 699 | the -fomit-frame-pointer or -O3 options, the |
| 700 | "mov sp,aN" instruction will be followed by an |
| 701 | "add #,aN" instruction. This indicates the |
| 702 | "stack_size", the size of the portion of the stack |
| 703 | containing the arguments. This instruction format is: |
| 704 | add #,aN = 0010 00XX YYYY YYYY |
| 705 | where XX is the register number |
| 706 | YYYY YYYY is the constant. |
| 707 | Note the size of the stack (as a negative number) in |
| 708 | the frame info structure. */ |
| 709 | if (fi) |
| 710 | stack_extra_size += -buf[2]; |
| 711 | |
| 712 | addr += 2; |
| 713 | } |
| 714 | } |
| 715 | |
| 716 | if ((buf[0] & 0xfc) == 0x3c || |
| 717 | buf[0] == 0xf9 || buf[0] == 0xfb) |
| 718 | { |
| 719 | /* An "fmov" instruction has been found indicating that this |
| 720 | prologue saves floating point registers (or, as described |
| 721 | above, a "mov sp,aN" and possible "add #,aN" have been |
| 722 | found and we will assume an "fmov" follows). Process the |
| 723 | consecutive "fmov" instructions. */ |
| 724 | for (addr += 2 + imm_size;;addr += imm_size) |
| 725 | { |
| 726 | int regnum; |
| 727 | |
| 728 | /* Read the "fmov" instruction. */ |
| 729 | if (addr >= stop || |
| 730 | !safe_frame_unwind_memory (fi, addr, buf, 4)) |
| 731 | goto finish_prologue; |
| 732 | |
| 733 | if (buf[0] != 0xf9 && buf[0] != 0xfb) |
| 734 | break; |
| 735 | |
| 736 | /* An fmov instruction has just been seen. We can |
| 737 | now really commit to the pattern match. */ |
| 738 | |
| 739 | fmov_found = 1; |
| 740 | |
| 741 | /* Get the floating point register number from the |
| 742 | 2nd and 3rd bytes of the "fmov" instruction: |
| 743 | Machine Code: 0000 00X0 YYYY 0000 => |
| 744 | Regnum: 000X YYYY */ |
| 745 | regnum = (buf[1] & 0x02) << 3; |
| 746 | regnum |= ((buf[2] & 0xf0) >> 4) & 0x0f; |
| 747 | |
| 748 | /* Add this register number to the bit mask of floating |
| 749 | point registers that have been saved. */ |
| 750 | fpregmask |= 1 << regnum; |
| 751 | |
| 752 | /* Determine the length of this "fmov" instruction. |
| 753 | fmov fs#,(sp) => 3 byte instruction |
| 754 | fmov fs#,(#,sp) => 4 byte instruction */ |
| 755 | imm_size = (buf[0] == 0xf9) ? 3 : 4; |
| 756 | } |
| 757 | } |
| 758 | } |
| 759 | } |
| 760 | /* If no fmov instructions were found by the above sequence, reset |
| 761 | the state and pretend that the above bit of code never happened. */ |
| 762 | if (!fmov_found) |
| 763 | { |
| 764 | addr = restore_addr; |
| 765 | status = target_read_memory (addr, buf, 2); |
| 766 | if (status != 0) |
| 767 | goto finish_prologue; |
| 768 | stack_extra_size = 0; |
| 769 | } |
| 770 | } |
| 771 | |
| 772 | /* Now see if we set up a frame pointer via "mov sp,a3" */ |
| 773 | if (buf[0] == 0x3f) |
| 774 | { |
| 775 | addr += 1; |
| 776 | |
| 777 | /* The frame pointer is now valid. */ |
| 778 | if (fi) |
| 779 | { |
| 780 | frame_in_fp = 1; |
| 781 | } |
| 782 | |
| 783 | /* Quit now if we're beyond the stop point. */ |
| 784 | if (addr >= stop) |
| 785 | goto finish_prologue; |
| 786 | |
| 787 | /* Get two more bytes so scanning can continue. */ |
| 788 | if (!safe_frame_unwind_memory (fi, addr, buf, 2)) |
| 789 | goto finish_prologue; |
| 790 | } |
| 791 | |
| 792 | /* Next we should allocate the local frame. No more prologue insns |
| 793 | are found after allocating the local frame. |
| 794 | |
| 795 | Search for add imm8,sp (0xf8feXX) |
| 796 | or add imm16,sp (0xfafeXXXX) |
| 797 | or add imm32,sp (0xfcfeXXXXXXXX). |
| 798 | |
| 799 | If none of the above was found, then this prologue has no |
| 800 | additional stack. */ |
| 801 | |
| 802 | imm_size = 0; |
| 803 | if (buf[0] == 0xf8 && buf[1] == 0xfe) |
| 804 | imm_size = 1; |
| 805 | else if (buf[0] == 0xfa && buf[1] == 0xfe) |
| 806 | imm_size = 2; |
| 807 | else if (buf[0] == 0xfc && buf[1] == 0xfe) |
| 808 | imm_size = 4; |
| 809 | |
| 810 | if (imm_size != 0) |
| 811 | { |
| 812 | /* Suck in imm_size more bytes, they'll hold the size of the |
| 813 | current frame. */ |
| 814 | if (!safe_frame_unwind_memory (fi, addr + 2, buf, imm_size)) |
| 815 | goto finish_prologue; |
| 816 | |
| 817 | /* Note the size of the stack. */ |
| 818 | stack_extra_size -= extract_signed_integer (buf, imm_size); |
| 819 | |
| 820 | /* We just consumed 2 + imm_size bytes. */ |
| 821 | addr += 2 + imm_size; |
| 822 | |
| 823 | /* No more prologue insns follow, so begin preparation to return. */ |
| 824 | goto finish_prologue; |
| 825 | } |
| 826 | /* Do the essentials and get out of here. */ |
| 827 | finish_prologue: |
| 828 | /* Note if/where callee saved registers were saved. */ |
| 829 | if (fi) |
| 830 | set_reg_offsets (fi, this_cache, movm_args, fpregmask, stack_extra_size, |
| 831 | frame_in_fp); |
| 832 | return addr; |
| 833 | } |
| 834 | |
| 835 | /* Function: skip_prologue |
| 836 | Return the address of the first inst past the prologue of the function. */ |
| 837 | |
| 838 | static CORE_ADDR |
| 839 | mn10300_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 840 | { |
| 841 | return mn10300_analyze_prologue (gdbarch, NULL, NULL, pc); |
| 842 | } |
| 843 | |
| 844 | /* Simple frame_unwind_cache. |
| 845 | This finds the "extra info" for the frame. */ |
| 846 | struct trad_frame_cache * |
| 847 | mn10300_frame_unwind_cache (struct frame_info *next_frame, |
| 848 | void **this_prologue_cache) |
| 849 | { |
| 850 | struct gdbarch *gdbarch; |
| 851 | struct trad_frame_cache *cache; |
| 852 | CORE_ADDR pc, start, end; |
| 853 | void *cache_p; |
| 854 | |
| 855 | if (*this_prologue_cache) |
| 856 | return (*this_prologue_cache); |
| 857 | |
| 858 | gdbarch = get_frame_arch (next_frame); |
| 859 | cache_p = trad_frame_cache_zalloc (next_frame); |
| 860 | pc = gdbarch_unwind_pc (gdbarch, next_frame); |
| 861 | mn10300_analyze_prologue (gdbarch, next_frame, &cache_p, pc); |
| 862 | cache = cache_p; |
| 863 | |
| 864 | if (find_pc_partial_function (pc, NULL, &start, &end)) |
| 865 | trad_frame_set_id (cache, |
| 866 | frame_id_build (trad_frame_get_this_base (cache), |
| 867 | start)); |
| 868 | else |
| 869 | { |
| 870 | start = frame_func_unwind (next_frame, NORMAL_FRAME); |
| 871 | trad_frame_set_id (cache, |
| 872 | frame_id_build (trad_frame_get_this_base (cache), |
| 873 | start)); |
| 874 | } |
| 875 | |
| 876 | (*this_prologue_cache) = cache; |
| 877 | return cache; |
| 878 | } |
| 879 | |
| 880 | /* Here is a dummy implementation. */ |
| 881 | static struct frame_id |
| 882 | mn10300_unwind_dummy_id (struct gdbarch *gdbarch, |
| 883 | struct frame_info *next_frame) |
| 884 | { |
| 885 | return frame_id_build (frame_sp_unwind (next_frame), |
| 886 | frame_pc_unwind (next_frame)); |
| 887 | } |
| 888 | |
| 889 | /* Trad frame implementation. */ |
| 890 | static void |
| 891 | mn10300_frame_this_id (struct frame_info *next_frame, |
| 892 | void **this_prologue_cache, |
| 893 | struct frame_id *this_id) |
| 894 | { |
| 895 | struct trad_frame_cache *cache = |
| 896 | mn10300_frame_unwind_cache (next_frame, this_prologue_cache); |
| 897 | |
| 898 | trad_frame_get_id (cache, this_id); |
| 899 | } |
| 900 | |
| 901 | static void |
| 902 | mn10300_frame_prev_register (struct frame_info *next_frame, |
| 903 | void **this_prologue_cache, |
| 904 | int regnum, int *optimizedp, |
| 905 | enum lval_type *lvalp, CORE_ADDR *addrp, |
| 906 | int *realnump, gdb_byte *bufferp) |
| 907 | { |
| 908 | struct trad_frame_cache *cache = |
| 909 | mn10300_frame_unwind_cache (next_frame, this_prologue_cache); |
| 910 | |
| 911 | trad_frame_get_register (cache, next_frame, regnum, optimizedp, |
| 912 | lvalp, addrp, realnump, bufferp); |
| 913 | /* Or... |
| 914 | trad_frame_get_prev_register (next_frame, cache->prev_regs, regnum, |
| 915 | optimizedp, lvalp, addrp, realnump, bufferp); |
| 916 | */ |
| 917 | } |
| 918 | |
| 919 | static const struct frame_unwind mn10300_frame_unwind = { |
| 920 | NORMAL_FRAME, |
| 921 | mn10300_frame_this_id, |
| 922 | mn10300_frame_prev_register |
| 923 | }; |
| 924 | |
| 925 | static CORE_ADDR |
| 926 | mn10300_frame_base_address (struct frame_info *next_frame, |
| 927 | void **this_prologue_cache) |
| 928 | { |
| 929 | struct trad_frame_cache *cache = |
| 930 | mn10300_frame_unwind_cache (next_frame, this_prologue_cache); |
| 931 | |
| 932 | return trad_frame_get_this_base (cache); |
| 933 | } |
| 934 | |
| 935 | static const struct frame_unwind * |
| 936 | mn10300_frame_sniffer (struct frame_info *next_frame) |
| 937 | { |
| 938 | return &mn10300_frame_unwind; |
| 939 | } |
| 940 | |
| 941 | static const struct frame_base mn10300_frame_base = { |
| 942 | &mn10300_frame_unwind, |
| 943 | mn10300_frame_base_address, |
| 944 | mn10300_frame_base_address, |
| 945 | mn10300_frame_base_address |
| 946 | }; |
| 947 | |
| 948 | static CORE_ADDR |
| 949 | mn10300_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame) |
| 950 | { |
| 951 | ULONGEST pc; |
| 952 | |
| 953 | pc = frame_unwind_register_unsigned (next_frame, E_PC_REGNUM); |
| 954 | return pc; |
| 955 | } |
| 956 | |
| 957 | static CORE_ADDR |
| 958 | mn10300_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame) |
| 959 | { |
| 960 | ULONGEST sp; |
| 961 | |
| 962 | sp = frame_unwind_register_unsigned (next_frame, E_SP_REGNUM); |
| 963 | return sp; |
| 964 | } |
| 965 | |
| 966 | static void |
| 967 | mn10300_frame_unwind_init (struct gdbarch *gdbarch) |
| 968 | { |
| 969 | frame_unwind_append_sniffer (gdbarch, dwarf2_frame_sniffer); |
| 970 | frame_unwind_append_sniffer (gdbarch, mn10300_frame_sniffer); |
| 971 | frame_base_set_default (gdbarch, &mn10300_frame_base); |
| 972 | set_gdbarch_unwind_dummy_id (gdbarch, mn10300_unwind_dummy_id); |
| 973 | set_gdbarch_unwind_pc (gdbarch, mn10300_unwind_pc); |
| 974 | set_gdbarch_unwind_sp (gdbarch, mn10300_unwind_sp); |
| 975 | } |
| 976 | |
| 977 | /* Function: push_dummy_call |
| 978 | * |
| 979 | * Set up machine state for a target call, including |
| 980 | * function arguments, stack, return address, etc. |
| 981 | * |
| 982 | */ |
| 983 | |
| 984 | static CORE_ADDR |
| 985 | mn10300_push_dummy_call (struct gdbarch *gdbarch, |
| 986 | struct value *target_func, |
| 987 | struct regcache *regcache, |
| 988 | CORE_ADDR bp_addr, |
| 989 | int nargs, struct value **args, |
| 990 | CORE_ADDR sp, |
| 991 | int struct_return, |
| 992 | CORE_ADDR struct_addr) |
| 993 | { |
| 994 | const int push_size = register_size (gdbarch, E_PC_REGNUM); |
| 995 | int regs_used; |
| 996 | int len, arg_len; |
| 997 | int stack_offset = 0; |
| 998 | int argnum; |
| 999 | char *val, valbuf[MAX_REGISTER_SIZE]; |
| 1000 | |
| 1001 | /* This should be a nop, but align the stack just in case something |
| 1002 | went wrong. Stacks are four byte aligned on the mn10300. */ |
| 1003 | sp &= ~3; |
| 1004 | |
| 1005 | /* Now make space on the stack for the args. |
| 1006 | |
| 1007 | XXX This doesn't appear to handle pass-by-invisible reference |
| 1008 | arguments. */ |
| 1009 | regs_used = struct_return ? 1 : 0; |
| 1010 | for (len = 0, argnum = 0; argnum < nargs; argnum++) |
| 1011 | { |
| 1012 | arg_len = (TYPE_LENGTH (value_type (args[argnum])) + 3) & ~3; |
| 1013 | while (regs_used < 2 && arg_len > 0) |
| 1014 | { |
| 1015 | regs_used++; |
| 1016 | arg_len -= push_size; |
| 1017 | } |
| 1018 | len += arg_len; |
| 1019 | } |
| 1020 | |
| 1021 | /* Allocate stack space. */ |
| 1022 | sp -= len; |
| 1023 | |
| 1024 | if (struct_return) |
| 1025 | { |
| 1026 | regs_used = 1; |
| 1027 | regcache_cooked_write_unsigned (regcache, E_D0_REGNUM, struct_addr); |
| 1028 | } |
| 1029 | else |
| 1030 | regs_used = 0; |
| 1031 | |
| 1032 | /* Push all arguments onto the stack. */ |
| 1033 | for (argnum = 0; argnum < nargs; argnum++) |
| 1034 | { |
| 1035 | /* FIXME what about structs? Unions? */ |
| 1036 | if (TYPE_CODE (value_type (*args)) == TYPE_CODE_STRUCT |
| 1037 | && TYPE_LENGTH (value_type (*args)) > 8) |
| 1038 | { |
| 1039 | /* Change to pointer-to-type. */ |
| 1040 | arg_len = push_size; |
| 1041 | store_unsigned_integer (valbuf, push_size, |
| 1042 | VALUE_ADDRESS (*args)); |
| 1043 | val = &valbuf[0]; |
| 1044 | } |
| 1045 | else |
| 1046 | { |
| 1047 | arg_len = TYPE_LENGTH (value_type (*args)); |
| 1048 | val = (char *) value_contents (*args); |
| 1049 | } |
| 1050 | |
| 1051 | while (regs_used < 2 && arg_len > 0) |
| 1052 | { |
| 1053 | regcache_cooked_write_unsigned (regcache, regs_used, |
| 1054 | extract_unsigned_integer (val, push_size)); |
| 1055 | val += push_size; |
| 1056 | arg_len -= push_size; |
| 1057 | regs_used++; |
| 1058 | } |
| 1059 | |
| 1060 | while (arg_len > 0) |
| 1061 | { |
| 1062 | write_memory (sp + stack_offset, val, push_size); |
| 1063 | arg_len -= push_size; |
| 1064 | val += push_size; |
| 1065 | stack_offset += push_size; |
| 1066 | } |
| 1067 | |
| 1068 | args++; |
| 1069 | } |
| 1070 | |
| 1071 | /* Make space for the flushback area. */ |
| 1072 | sp -= 8; |
| 1073 | |
| 1074 | /* Push the return address that contains the magic breakpoint. */ |
| 1075 | sp -= 4; |
| 1076 | write_memory_unsigned_integer (sp, push_size, bp_addr); |
| 1077 | |
| 1078 | /* The CPU also writes the return address always into the |
| 1079 | MDR register on "call". */ |
| 1080 | regcache_cooked_write_unsigned (regcache, E_MDR_REGNUM, bp_addr); |
| 1081 | |
| 1082 | /* Update $sp. */ |
| 1083 | regcache_cooked_write_unsigned (regcache, E_SP_REGNUM, sp); |
| 1084 | |
| 1085 | /* On the mn10300, it's possible to move some of the stack adjustment |
| 1086 | and saving of the caller-save registers out of the prologue and |
| 1087 | into the call sites. (When using gcc, this optimization can |
| 1088 | occur when using the -mrelax switch.) If this occurs, the dwarf2 |
| 1089 | info will reflect this fact. We can test to see if this is the |
| 1090 | case by creating a new frame using the current stack pointer and |
| 1091 | the address of the function that we're about to call. We then |
| 1092 | unwind SP and see if it's different than the SP of our newly |
| 1093 | created frame. If the SP values are the same, the caller is not |
| 1094 | expected to allocate any additional stack. On the other hand, if |
| 1095 | the SP values are different, the difference determines the |
| 1096 | additional stack that must be allocated. |
| 1097 | |
| 1098 | Note that we don't update the return value though because that's |
| 1099 | the value of the stack just after pushing the arguments, but prior |
| 1100 | to performing the call. This value is needed in order to |
| 1101 | construct the frame ID of the dummy call. */ |
| 1102 | { |
| 1103 | CORE_ADDR func_addr = find_function_addr (target_func, NULL); |
| 1104 | CORE_ADDR unwound_sp |
| 1105 | = mn10300_unwind_sp (gdbarch, create_new_frame (sp, func_addr)); |
| 1106 | if (sp != unwound_sp) |
| 1107 | regcache_cooked_write_unsigned (regcache, E_SP_REGNUM, |
| 1108 | sp - (unwound_sp - sp)); |
| 1109 | } |
| 1110 | |
| 1111 | return sp; |
| 1112 | } |
| 1113 | |
| 1114 | /* If DWARF2 is a register number appearing in Dwarf2 debug info, then |
| 1115 | mn10300_dwarf2_reg_to_regnum (DWARF2) is the corresponding GDB |
| 1116 | register number. Why don't Dwarf2 and GDB use the same numbering? |
| 1117 | Who knows? But since people have object files lying around with |
| 1118 | the existing Dwarf2 numbering, and other people have written stubs |
| 1119 | to work with the existing GDB, neither of them can change. So we |
| 1120 | just have to cope. */ |
| 1121 | static int |
| 1122 | mn10300_dwarf2_reg_to_regnum (struct gdbarch *gdbarch, int dwarf2) |
| 1123 | { |
| 1124 | /* This table is supposed to be shaped like the gdbarch_register_name |
| 1125 | initializer in gcc/config/mn10300/mn10300.h. Registers which |
| 1126 | appear in GCC's numbering, but have no counterpart in GDB's |
| 1127 | world, are marked with a -1. */ |
| 1128 | static int dwarf2_to_gdb[] = { |
| 1129 | 0, 1, 2, 3, 4, 5, 6, 7, -1, 8, |
| 1130 | 15, 16, 17, 18, 19, 20, 21, 22, |
| 1131 | 32, 33, 34, 35, 36, 37, 38, 39, |
| 1132 | 40, 41, 42, 43, 44, 45, 46, 47, |
| 1133 | 48, 49, 50, 51, 52, 53, 54, 55, |
| 1134 | 56, 57, 58, 59, 60, 61, 62, 63, |
| 1135 | 9 |
| 1136 | }; |
| 1137 | |
| 1138 | if (dwarf2 < 0 |
| 1139 | || dwarf2 >= ARRAY_SIZE (dwarf2_to_gdb)) |
| 1140 | { |
| 1141 | warning (_("Bogus register number in debug info: %d"), dwarf2); |
| 1142 | return -1; |
| 1143 | } |
| 1144 | |
| 1145 | return dwarf2_to_gdb[dwarf2]; |
| 1146 | } |
| 1147 | |
| 1148 | static struct gdbarch * |
| 1149 | mn10300_gdbarch_init (struct gdbarch_info info, |
| 1150 | struct gdbarch_list *arches) |
| 1151 | { |
| 1152 | struct gdbarch *gdbarch; |
| 1153 | struct gdbarch_tdep *tdep; |
| 1154 | int num_regs; |
| 1155 | |
| 1156 | arches = gdbarch_list_lookup_by_info (arches, &info); |
| 1157 | if (arches != NULL) |
| 1158 | return arches->gdbarch; |
| 1159 | |
| 1160 | tdep = xmalloc (sizeof (struct gdbarch_tdep)); |
| 1161 | gdbarch = gdbarch_alloc (&info, tdep); |
| 1162 | |
| 1163 | switch (info.bfd_arch_info->mach) |
| 1164 | { |
| 1165 | case 0: |
| 1166 | case bfd_mach_mn10300: |
| 1167 | set_gdbarch_register_name (gdbarch, mn10300_generic_register_name); |
| 1168 | tdep->am33_mode = 0; |
| 1169 | num_regs = 32; |
| 1170 | break; |
| 1171 | case bfd_mach_am33: |
| 1172 | set_gdbarch_register_name (gdbarch, am33_register_name); |
| 1173 | tdep->am33_mode = 1; |
| 1174 | num_regs = 32; |
| 1175 | break; |
| 1176 | case bfd_mach_am33_2: |
| 1177 | set_gdbarch_register_name (gdbarch, am33_2_register_name); |
| 1178 | tdep->am33_mode = 2; |
| 1179 | num_regs = 64; |
| 1180 | set_gdbarch_fp0_regnum (gdbarch, 32); |
| 1181 | break; |
| 1182 | default: |
| 1183 | internal_error (__FILE__, __LINE__, |
| 1184 | _("mn10300_gdbarch_init: Unknown mn10300 variant")); |
| 1185 | break; |
| 1186 | } |
| 1187 | |
| 1188 | /* Registers. */ |
| 1189 | set_gdbarch_num_regs (gdbarch, num_regs); |
| 1190 | set_gdbarch_register_type (gdbarch, mn10300_register_type); |
| 1191 | set_gdbarch_skip_prologue (gdbarch, mn10300_skip_prologue); |
| 1192 | set_gdbarch_read_pc (gdbarch, mn10300_read_pc); |
| 1193 | set_gdbarch_write_pc (gdbarch, mn10300_write_pc); |
| 1194 | set_gdbarch_pc_regnum (gdbarch, E_PC_REGNUM); |
| 1195 | set_gdbarch_sp_regnum (gdbarch, E_SP_REGNUM); |
| 1196 | set_gdbarch_dwarf2_reg_to_regnum (gdbarch, mn10300_dwarf2_reg_to_regnum); |
| 1197 | |
| 1198 | /* Stack unwinding. */ |
| 1199 | set_gdbarch_inner_than (gdbarch, core_addr_lessthan); |
| 1200 | /* Breakpoints. */ |
| 1201 | set_gdbarch_breakpoint_from_pc (gdbarch, mn10300_breakpoint_from_pc); |
| 1202 | /* decr_pc_after_break? */ |
| 1203 | /* Disassembly. */ |
| 1204 | set_gdbarch_print_insn (gdbarch, print_insn_mn10300); |
| 1205 | |
| 1206 | /* Stage 2 */ |
| 1207 | set_gdbarch_return_value (gdbarch, mn10300_return_value); |
| 1208 | |
| 1209 | /* Stage 3 -- get target calls working. */ |
| 1210 | set_gdbarch_push_dummy_call (gdbarch, mn10300_push_dummy_call); |
| 1211 | /* set_gdbarch_return_value (store, extract) */ |
| 1212 | |
| 1213 | |
| 1214 | mn10300_frame_unwind_init (gdbarch); |
| 1215 | |
| 1216 | /* Hook in ABI-specific overrides, if they have been registered. */ |
| 1217 | gdbarch_init_osabi (info, gdbarch); |
| 1218 | |
| 1219 | return gdbarch; |
| 1220 | } |
| 1221 | |
| 1222 | /* Dump out the mn10300 specific architecture information. */ |
| 1223 | |
| 1224 | static void |
| 1225 | mn10300_dump_tdep (struct gdbarch *gdbarch, struct ui_file *file) |
| 1226 | { |
| 1227 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 1228 | fprintf_unfiltered (file, "mn10300_dump_tdep: am33_mode = %d\n", |
| 1229 | tdep->am33_mode); |
| 1230 | } |
| 1231 | |
| 1232 | void |
| 1233 | _initialize_mn10300_tdep (void) |
| 1234 | { |
| 1235 | gdbarch_register (bfd_arch_mn10300, mn10300_gdbarch_init, mn10300_dump_tdep); |
| 1236 | } |
| 1237 | |