| 1 | /* Intel 386 target-dependent stuff. |
| 2 | |
| 3 | Copyright 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, |
| 4 | 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software |
| 5 | Foundation, Inc. |
| 6 | |
| 7 | This file is part of GDB. |
| 8 | |
| 9 | This program is free software; you can redistribute it and/or modify |
| 10 | it under the terms of the GNU General Public License as published by |
| 11 | the Free Software Foundation; either version 2 of the License, or |
| 12 | (at your option) any later version. |
| 13 | |
| 14 | This program is distributed in the hope that it will be useful, |
| 15 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 17 | GNU General Public License for more details. |
| 18 | |
| 19 | You should have received a copy of the GNU General Public License |
| 20 | along with this program; if not, write to the Free Software |
| 21 | Foundation, Inc., 59 Temple Place - Suite 330, |
| 22 | Boston, MA 02111-1307, USA. */ |
| 23 | |
| 24 | #include "defs.h" |
| 25 | #include "arch-utils.h" |
| 26 | #include "command.h" |
| 27 | #include "dummy-frame.h" |
| 28 | #include "dwarf2-frame.h" |
| 29 | #include "doublest.h" |
| 30 | #include "floatformat.h" |
| 31 | #include "frame.h" |
| 32 | #include "frame-base.h" |
| 33 | #include "frame-unwind.h" |
| 34 | #include "inferior.h" |
| 35 | #include "gdbcmd.h" |
| 36 | #include "gdbcore.h" |
| 37 | #include "objfiles.h" |
| 38 | #include "osabi.h" |
| 39 | #include "regcache.h" |
| 40 | #include "reggroups.h" |
| 41 | #include "regset.h" |
| 42 | #include "symfile.h" |
| 43 | #include "symtab.h" |
| 44 | #include "target.h" |
| 45 | #include "value.h" |
| 46 | #include "dis-asm.h" |
| 47 | |
| 48 | #include "gdb_assert.h" |
| 49 | #include "gdb_string.h" |
| 50 | |
| 51 | #include "i386-tdep.h" |
| 52 | #include "i387-tdep.h" |
| 53 | |
| 54 | /* Register names. */ |
| 55 | |
| 56 | static char *i386_register_names[] = |
| 57 | { |
| 58 | "eax", "ecx", "edx", "ebx", |
| 59 | "esp", "ebp", "esi", "edi", |
| 60 | "eip", "eflags", "cs", "ss", |
| 61 | "ds", "es", "fs", "gs", |
| 62 | "st0", "st1", "st2", "st3", |
| 63 | "st4", "st5", "st6", "st7", |
| 64 | "fctrl", "fstat", "ftag", "fiseg", |
| 65 | "fioff", "foseg", "fooff", "fop", |
| 66 | "xmm0", "xmm1", "xmm2", "xmm3", |
| 67 | "xmm4", "xmm5", "xmm6", "xmm7", |
| 68 | "mxcsr" |
| 69 | }; |
| 70 | |
| 71 | static const int i386_num_register_names = ARRAY_SIZE (i386_register_names); |
| 72 | |
| 73 | /* Register names for MMX pseudo-registers. */ |
| 74 | |
| 75 | static char *i386_mmx_names[] = |
| 76 | { |
| 77 | "mm0", "mm1", "mm2", "mm3", |
| 78 | "mm4", "mm5", "mm6", "mm7" |
| 79 | }; |
| 80 | |
| 81 | static const int i386_num_mmx_regs = ARRAY_SIZE (i386_mmx_names); |
| 82 | |
| 83 | static int |
| 84 | i386_mmx_regnum_p (struct gdbarch *gdbarch, int regnum) |
| 85 | { |
| 86 | int mm0_regnum = gdbarch_tdep (gdbarch)->mm0_regnum; |
| 87 | |
| 88 | if (mm0_regnum < 0) |
| 89 | return 0; |
| 90 | |
| 91 | return (regnum >= mm0_regnum && regnum < mm0_regnum + i386_num_mmx_regs); |
| 92 | } |
| 93 | |
| 94 | /* SSE register? */ |
| 95 | |
| 96 | static int |
| 97 | i386_sse_regnum_p (struct gdbarch *gdbarch, int regnum) |
| 98 | { |
| 99 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 100 | |
| 101 | #define I387_ST0_REGNUM tdep->st0_regnum |
| 102 | #define I387_NUM_XMM_REGS tdep->num_xmm_regs |
| 103 | |
| 104 | if (I387_NUM_XMM_REGS == 0) |
| 105 | return 0; |
| 106 | |
| 107 | return (I387_XMM0_REGNUM <= regnum && regnum < I387_MXCSR_REGNUM); |
| 108 | |
| 109 | #undef I387_ST0_REGNUM |
| 110 | #undef I387_NUM_XMM_REGS |
| 111 | } |
| 112 | |
| 113 | static int |
| 114 | i386_mxcsr_regnum_p (struct gdbarch *gdbarch, int regnum) |
| 115 | { |
| 116 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 117 | |
| 118 | #define I387_ST0_REGNUM tdep->st0_regnum |
| 119 | #define I387_NUM_XMM_REGS tdep->num_xmm_regs |
| 120 | |
| 121 | if (I387_NUM_XMM_REGS == 0) |
| 122 | return 0; |
| 123 | |
| 124 | return (regnum == I387_MXCSR_REGNUM); |
| 125 | |
| 126 | #undef I387_ST0_REGNUM |
| 127 | #undef I387_NUM_XMM_REGS |
| 128 | } |
| 129 | |
| 130 | #define I387_ST0_REGNUM (gdbarch_tdep (current_gdbarch)->st0_regnum) |
| 131 | #define I387_MM0_REGNUM (gdbarch_tdep (current_gdbarch)->mm0_regnum) |
| 132 | #define I387_NUM_XMM_REGS (gdbarch_tdep (current_gdbarch)->num_xmm_regs) |
| 133 | |
| 134 | /* FP register? */ |
| 135 | |
| 136 | int |
| 137 | i386_fp_regnum_p (int regnum) |
| 138 | { |
| 139 | if (I387_ST0_REGNUM < 0) |
| 140 | return 0; |
| 141 | |
| 142 | return (I387_ST0_REGNUM <= regnum && regnum < I387_FCTRL_REGNUM); |
| 143 | } |
| 144 | |
| 145 | int |
| 146 | i386_fpc_regnum_p (int regnum) |
| 147 | { |
| 148 | if (I387_ST0_REGNUM < 0) |
| 149 | return 0; |
| 150 | |
| 151 | return (I387_FCTRL_REGNUM <= regnum && regnum < I387_XMM0_REGNUM); |
| 152 | } |
| 153 | |
| 154 | /* Return the name of register REGNUM. */ |
| 155 | |
| 156 | const char * |
| 157 | i386_register_name (int regnum) |
| 158 | { |
| 159 | if (i386_mmx_regnum_p (current_gdbarch, regnum)) |
| 160 | return i386_mmx_names[regnum - I387_MM0_REGNUM]; |
| 161 | |
| 162 | if (regnum >= 0 && regnum < i386_num_register_names) |
| 163 | return i386_register_names[regnum]; |
| 164 | |
| 165 | return NULL; |
| 166 | } |
| 167 | |
| 168 | /* Convert a dbx register number REG to the appropriate register |
| 169 | number used by GDB. */ |
| 170 | |
| 171 | static int |
| 172 | i386_dbx_reg_to_regnum (int reg) |
| 173 | { |
| 174 | /* This implements what GCC calls the "default" register map |
| 175 | (dbx_register_map[]). */ |
| 176 | |
| 177 | if (reg >= 0 && reg <= 7) |
| 178 | { |
| 179 | /* General-purpose registers. The debug info calls %ebp |
| 180 | register 4, and %esp register 5. */ |
| 181 | if (reg == 4) |
| 182 | return 5; |
| 183 | else if (reg == 5) |
| 184 | return 4; |
| 185 | else return reg; |
| 186 | } |
| 187 | else if (reg >= 12 && reg <= 19) |
| 188 | { |
| 189 | /* Floating-point registers. */ |
| 190 | return reg - 12 + I387_ST0_REGNUM; |
| 191 | } |
| 192 | else if (reg >= 21 && reg <= 28) |
| 193 | { |
| 194 | /* SSE registers. */ |
| 195 | return reg - 21 + I387_XMM0_REGNUM; |
| 196 | } |
| 197 | else if (reg >= 29 && reg <= 36) |
| 198 | { |
| 199 | /* MMX registers. */ |
| 200 | return reg - 29 + I387_MM0_REGNUM; |
| 201 | } |
| 202 | |
| 203 | /* This will hopefully provoke a warning. */ |
| 204 | return NUM_REGS + NUM_PSEUDO_REGS; |
| 205 | } |
| 206 | |
| 207 | /* Convert SVR4 register number REG to the appropriate register number |
| 208 | used by GDB. */ |
| 209 | |
| 210 | static int |
| 211 | i386_svr4_reg_to_regnum (int reg) |
| 212 | { |
| 213 | /* This implements the GCC register map that tries to be compatible |
| 214 | with the SVR4 C compiler for DWARF (svr4_dbx_register_map[]). */ |
| 215 | |
| 216 | /* The SVR4 register numbering includes %eip and %eflags, and |
| 217 | numbers the floating point registers differently. */ |
| 218 | if (reg >= 0 && reg <= 9) |
| 219 | { |
| 220 | /* General-purpose registers. */ |
| 221 | return reg; |
| 222 | } |
| 223 | else if (reg >= 11 && reg <= 18) |
| 224 | { |
| 225 | /* Floating-point registers. */ |
| 226 | return reg - 11 + I387_ST0_REGNUM; |
| 227 | } |
| 228 | else if (reg >= 21 && reg <= 36) |
| 229 | { |
| 230 | /* The SSE and MMX registers have the same numbers as with dbx. */ |
| 231 | return i386_dbx_reg_to_regnum (reg); |
| 232 | } |
| 233 | |
| 234 | switch (reg) |
| 235 | { |
| 236 | case 37: return I387_FCTRL_REGNUM; |
| 237 | case 38: return I387_FSTAT_REGNUM; |
| 238 | case 39: return I387_MXCSR_REGNUM; |
| 239 | case 40: return I386_ES_REGNUM; |
| 240 | case 41: return I386_CS_REGNUM; |
| 241 | case 42: return I386_SS_REGNUM; |
| 242 | case 43: return I386_DS_REGNUM; |
| 243 | case 44: return I386_FS_REGNUM; |
| 244 | case 45: return I386_GS_REGNUM; |
| 245 | } |
| 246 | |
| 247 | /* This will hopefully provoke a warning. */ |
| 248 | return NUM_REGS + NUM_PSEUDO_REGS; |
| 249 | } |
| 250 | |
| 251 | #undef I387_ST0_REGNUM |
| 252 | #undef I387_MM0_REGNUM |
| 253 | #undef I387_NUM_XMM_REGS |
| 254 | \f |
| 255 | |
| 256 | /* This is the variable that is set with "set disassembly-flavor", and |
| 257 | its legitimate values. */ |
| 258 | static const char att_flavor[] = "att"; |
| 259 | static const char intel_flavor[] = "intel"; |
| 260 | static const char *valid_flavors[] = |
| 261 | { |
| 262 | att_flavor, |
| 263 | intel_flavor, |
| 264 | NULL |
| 265 | }; |
| 266 | static const char *disassembly_flavor = att_flavor; |
| 267 | \f |
| 268 | |
| 269 | /* Use the program counter to determine the contents and size of a |
| 270 | breakpoint instruction. Return a pointer to a string of bytes that |
| 271 | encode a breakpoint instruction, store the length of the string in |
| 272 | *LEN and optionally adjust *PC to point to the correct memory |
| 273 | location for inserting the breakpoint. |
| 274 | |
| 275 | On the i386 we have a single breakpoint that fits in a single byte |
| 276 | and can be inserted anywhere. |
| 277 | |
| 278 | This function is 64-bit safe. */ |
| 279 | |
| 280 | static const gdb_byte * |
| 281 | i386_breakpoint_from_pc (CORE_ADDR *pc, int *len) |
| 282 | { |
| 283 | static gdb_byte break_insn[] = { 0xcc }; /* int 3 */ |
| 284 | |
| 285 | *len = sizeof (break_insn); |
| 286 | return break_insn; |
| 287 | } |
| 288 | \f |
| 289 | #ifdef I386_REGNO_TO_SYMMETRY |
| 290 | #error "The Sequent Symmetry is no longer supported." |
| 291 | #endif |
| 292 | |
| 293 | /* According to the System V ABI, the registers %ebp, %ebx, %edi, %esi |
| 294 | and %esp "belong" to the calling function. Therefore these |
| 295 | registers should be saved if they're going to be modified. */ |
| 296 | |
| 297 | /* The maximum number of saved registers. This should include all |
| 298 | registers mentioned above, and %eip. */ |
| 299 | #define I386_NUM_SAVED_REGS I386_NUM_GREGS |
| 300 | |
| 301 | struct i386_frame_cache |
| 302 | { |
| 303 | /* Base address. */ |
| 304 | CORE_ADDR base; |
| 305 | LONGEST sp_offset; |
| 306 | CORE_ADDR pc; |
| 307 | |
| 308 | /* Saved registers. */ |
| 309 | CORE_ADDR saved_regs[I386_NUM_SAVED_REGS]; |
| 310 | CORE_ADDR saved_sp; |
| 311 | int pc_in_eax; |
| 312 | |
| 313 | /* Stack space reserved for local variables. */ |
| 314 | long locals; |
| 315 | }; |
| 316 | |
| 317 | /* Allocate and initialize a frame cache. */ |
| 318 | |
| 319 | static struct i386_frame_cache * |
| 320 | i386_alloc_frame_cache (void) |
| 321 | { |
| 322 | struct i386_frame_cache *cache; |
| 323 | int i; |
| 324 | |
| 325 | cache = FRAME_OBSTACK_ZALLOC (struct i386_frame_cache); |
| 326 | |
| 327 | /* Base address. */ |
| 328 | cache->base = 0; |
| 329 | cache->sp_offset = -4; |
| 330 | cache->pc = 0; |
| 331 | |
| 332 | /* Saved registers. We initialize these to -1 since zero is a valid |
| 333 | offset (that's where %ebp is supposed to be stored). */ |
| 334 | for (i = 0; i < I386_NUM_SAVED_REGS; i++) |
| 335 | cache->saved_regs[i] = -1; |
| 336 | cache->saved_sp = 0; |
| 337 | cache->pc_in_eax = 0; |
| 338 | |
| 339 | /* Frameless until proven otherwise. */ |
| 340 | cache->locals = -1; |
| 341 | |
| 342 | return cache; |
| 343 | } |
| 344 | |
| 345 | /* If the instruction at PC is a jump, return the address of its |
| 346 | target. Otherwise, return PC. */ |
| 347 | |
| 348 | static CORE_ADDR |
| 349 | i386_follow_jump (CORE_ADDR pc) |
| 350 | { |
| 351 | gdb_byte op; |
| 352 | long delta = 0; |
| 353 | int data16 = 0; |
| 354 | |
| 355 | op = read_memory_unsigned_integer (pc, 1); |
| 356 | if (op == 0x66) |
| 357 | { |
| 358 | data16 = 1; |
| 359 | op = read_memory_unsigned_integer (pc + 1, 1); |
| 360 | } |
| 361 | |
| 362 | switch (op) |
| 363 | { |
| 364 | case 0xe9: |
| 365 | /* Relative jump: if data16 == 0, disp32, else disp16. */ |
| 366 | if (data16) |
| 367 | { |
| 368 | delta = read_memory_integer (pc + 2, 2); |
| 369 | |
| 370 | /* Include the size of the jmp instruction (including the |
| 371 | 0x66 prefix). */ |
| 372 | delta += 4; |
| 373 | } |
| 374 | else |
| 375 | { |
| 376 | delta = read_memory_integer (pc + 1, 4); |
| 377 | |
| 378 | /* Include the size of the jmp instruction. */ |
| 379 | delta += 5; |
| 380 | } |
| 381 | break; |
| 382 | case 0xeb: |
| 383 | /* Relative jump, disp8 (ignore data16). */ |
| 384 | delta = read_memory_integer (pc + data16 + 1, 1); |
| 385 | |
| 386 | delta += data16 + 2; |
| 387 | break; |
| 388 | } |
| 389 | |
| 390 | return pc + delta; |
| 391 | } |
| 392 | |
| 393 | /* Check whether PC points at a prologue for a function returning a |
| 394 | structure or union. If so, it updates CACHE and returns the |
| 395 | address of the first instruction after the code sequence that |
| 396 | removes the "hidden" argument from the stack or CURRENT_PC, |
| 397 | whichever is smaller. Otherwise, return PC. */ |
| 398 | |
| 399 | static CORE_ADDR |
| 400 | i386_analyze_struct_return (CORE_ADDR pc, CORE_ADDR current_pc, |
| 401 | struct i386_frame_cache *cache) |
| 402 | { |
| 403 | /* Functions that return a structure or union start with: |
| 404 | |
| 405 | popl %eax 0x58 |
| 406 | xchgl %eax, (%esp) 0x87 0x04 0x24 |
| 407 | or xchgl %eax, 0(%esp) 0x87 0x44 0x24 0x00 |
| 408 | |
| 409 | (the System V compiler puts out the second `xchg' instruction, |
| 410 | and the assembler doesn't try to optimize it, so the 'sib' form |
| 411 | gets generated). This sequence is used to get the address of the |
| 412 | return buffer for a function that returns a structure. */ |
| 413 | static gdb_byte proto1[3] = { 0x87, 0x04, 0x24 }; |
| 414 | static gdb_byte proto2[4] = { 0x87, 0x44, 0x24, 0x00 }; |
| 415 | gdb_byte buf[4]; |
| 416 | gdb_byte op; |
| 417 | |
| 418 | if (current_pc <= pc) |
| 419 | return pc; |
| 420 | |
| 421 | op = read_memory_unsigned_integer (pc, 1); |
| 422 | |
| 423 | if (op != 0x58) /* popl %eax */ |
| 424 | return pc; |
| 425 | |
| 426 | read_memory (pc + 1, buf, 4); |
| 427 | if (memcmp (buf, proto1, 3) != 0 && memcmp (buf, proto2, 4) != 0) |
| 428 | return pc; |
| 429 | |
| 430 | if (current_pc == pc) |
| 431 | { |
| 432 | cache->sp_offset += 4; |
| 433 | return current_pc; |
| 434 | } |
| 435 | |
| 436 | if (current_pc == pc + 1) |
| 437 | { |
| 438 | cache->pc_in_eax = 1; |
| 439 | return current_pc; |
| 440 | } |
| 441 | |
| 442 | if (buf[1] == proto1[1]) |
| 443 | return pc + 4; |
| 444 | else |
| 445 | return pc + 5; |
| 446 | } |
| 447 | |
| 448 | static CORE_ADDR |
| 449 | i386_skip_probe (CORE_ADDR pc) |
| 450 | { |
| 451 | /* A function may start with |
| 452 | |
| 453 | pushl constant |
| 454 | call _probe |
| 455 | addl $4, %esp |
| 456 | |
| 457 | followed by |
| 458 | |
| 459 | pushl %ebp |
| 460 | |
| 461 | etc. */ |
| 462 | gdb_byte buf[8]; |
| 463 | gdb_byte op; |
| 464 | |
| 465 | op = read_memory_unsigned_integer (pc, 1); |
| 466 | |
| 467 | if (op == 0x68 || op == 0x6a) |
| 468 | { |
| 469 | int delta; |
| 470 | |
| 471 | /* Skip past the `pushl' instruction; it has either a one-byte or a |
| 472 | four-byte operand, depending on the opcode. */ |
| 473 | if (op == 0x68) |
| 474 | delta = 5; |
| 475 | else |
| 476 | delta = 2; |
| 477 | |
| 478 | /* Read the following 8 bytes, which should be `call _probe' (6 |
| 479 | bytes) followed by `addl $4,%esp' (2 bytes). */ |
| 480 | read_memory (pc + delta, buf, sizeof (buf)); |
| 481 | if (buf[0] == 0xe8 && buf[6] == 0xc4 && buf[7] == 0x4) |
| 482 | pc += delta + sizeof (buf); |
| 483 | } |
| 484 | |
| 485 | return pc; |
| 486 | } |
| 487 | |
| 488 | /* Maximum instruction length we need to handle. */ |
| 489 | #define I386_MAX_INSN_LEN 6 |
| 490 | |
| 491 | /* Instruction description. */ |
| 492 | struct i386_insn |
| 493 | { |
| 494 | size_t len; |
| 495 | gdb_byte insn[I386_MAX_INSN_LEN]; |
| 496 | gdb_byte mask[I386_MAX_INSN_LEN]; |
| 497 | }; |
| 498 | |
| 499 | /* Search for the instruction at PC in the list SKIP_INSNS. Return |
| 500 | the first instruction description that matches. Otherwise, return |
| 501 | NULL. */ |
| 502 | |
| 503 | static struct i386_insn * |
| 504 | i386_match_insn (CORE_ADDR pc, struct i386_insn *skip_insns) |
| 505 | { |
| 506 | struct i386_insn *insn; |
| 507 | gdb_byte op; |
| 508 | |
| 509 | op = read_memory_unsigned_integer (pc, 1); |
| 510 | |
| 511 | for (insn = skip_insns; insn->len > 0; insn++) |
| 512 | { |
| 513 | if ((op & insn->mask[0]) == insn->insn[0]) |
| 514 | { |
| 515 | gdb_byte buf[I386_MAX_INSN_LEN - 1]; |
| 516 | int insn_matched = 1; |
| 517 | size_t i; |
| 518 | |
| 519 | gdb_assert (insn->len > 1); |
| 520 | gdb_assert (insn->len <= I386_MAX_INSN_LEN); |
| 521 | |
| 522 | read_memory (pc + 1, buf, insn->len - 1); |
| 523 | for (i = 1; i < insn->len; i++) |
| 524 | { |
| 525 | if ((buf[i - 1] & insn->mask[i]) != insn->insn[i]) |
| 526 | insn_matched = 0; |
| 527 | } |
| 528 | |
| 529 | if (insn_matched) |
| 530 | return insn; |
| 531 | } |
| 532 | } |
| 533 | |
| 534 | return NULL; |
| 535 | } |
| 536 | |
| 537 | /* Some special instructions that might be migrated by GCC into the |
| 538 | part of the prologue that sets up the new stack frame. Because the |
| 539 | stack frame hasn't been setup yet, no registers have been saved |
| 540 | yet, and only the scratch registers %eax, %ecx and %edx can be |
| 541 | touched. */ |
| 542 | |
| 543 | struct i386_insn i386_frame_setup_skip_insns[] = |
| 544 | { |
| 545 | /* Check for `movb imm8, r' and `movl imm32, r'. |
| 546 | |
| 547 | ??? Should we handle 16-bit operand-sizes here? */ |
| 548 | |
| 549 | /* `movb imm8, %al' and `movb imm8, %ah' */ |
| 550 | /* `movb imm8, %cl' and `movb imm8, %ch' */ |
| 551 | { 2, { 0xb0, 0x00 }, { 0xfa, 0x00 } }, |
| 552 | /* `movb imm8, %dl' and `movb imm8, %dh' */ |
| 553 | { 2, { 0xb2, 0x00 }, { 0xfb, 0x00 } }, |
| 554 | /* `movl imm32, %eax' and `movl imm32, %ecx' */ |
| 555 | { 5, { 0xb8 }, { 0xfe } }, |
| 556 | /* `movl imm32, %edx' */ |
| 557 | { 5, { 0xba }, { 0xff } }, |
| 558 | |
| 559 | /* Check for `mov imm32, r32'. Note that there is an alternative |
| 560 | encoding for `mov m32, %eax'. |
| 561 | |
| 562 | ??? Should we handle SIB adressing here? |
| 563 | ??? Should we handle 16-bit operand-sizes here? */ |
| 564 | |
| 565 | /* `movl m32, %eax' */ |
| 566 | { 5, { 0xa1 }, { 0xff } }, |
| 567 | /* `movl m32, %eax' and `mov; m32, %ecx' */ |
| 568 | { 6, { 0x89, 0x05 }, {0xff, 0xf7 } }, |
| 569 | /* `movl m32, %edx' */ |
| 570 | { 6, { 0x89, 0x15 }, {0xff, 0xff } }, |
| 571 | |
| 572 | /* Check for `xorl r32, r32' and the equivalent `subl r32, r32'. |
| 573 | Because of the symmetry, there are actually two ways to encode |
| 574 | these instructions; opcode bytes 0x29 and 0x2b for `subl' and |
| 575 | opcode bytes 0x31 and 0x33 for `xorl'. */ |
| 576 | |
| 577 | /* `subl %eax, %eax' */ |
| 578 | { 2, { 0x29, 0xc0 }, { 0xfd, 0xff } }, |
| 579 | /* `subl %ecx, %ecx' */ |
| 580 | { 2, { 0x29, 0xc9 }, { 0xfd, 0xff } }, |
| 581 | /* `subl %edx, %edx' */ |
| 582 | { 2, { 0x29, 0xd2 }, { 0xfd, 0xff } }, |
| 583 | /* `xorl %eax, %eax' */ |
| 584 | { 2, { 0x31, 0xc0 }, { 0xfd, 0xff } }, |
| 585 | /* `xorl %ecx, %ecx' */ |
| 586 | { 2, { 0x31, 0xc9 }, { 0xfd, 0xff } }, |
| 587 | /* `xorl %edx, %edx' */ |
| 588 | { 2, { 0x31, 0xd2 }, { 0xfd, 0xff } }, |
| 589 | { 0 } |
| 590 | }; |
| 591 | |
| 592 | /* Check whether PC points at a code that sets up a new stack frame. |
| 593 | If so, it updates CACHE and returns the address of the first |
| 594 | instruction after the sequence that sets up the frame or LIMIT, |
| 595 | whichever is smaller. If we don't recognize the code, return PC. */ |
| 596 | |
| 597 | static CORE_ADDR |
| 598 | i386_analyze_frame_setup (CORE_ADDR pc, CORE_ADDR limit, |
| 599 | struct i386_frame_cache *cache) |
| 600 | { |
| 601 | struct i386_insn *insn; |
| 602 | gdb_byte op; |
| 603 | int skip = 0; |
| 604 | |
| 605 | if (limit <= pc) |
| 606 | return limit; |
| 607 | |
| 608 | op = read_memory_unsigned_integer (pc, 1); |
| 609 | |
| 610 | if (op == 0x55) /* pushl %ebp */ |
| 611 | { |
| 612 | /* Take into account that we've executed the `pushl %ebp' that |
| 613 | starts this instruction sequence. */ |
| 614 | cache->saved_regs[I386_EBP_REGNUM] = 0; |
| 615 | cache->sp_offset += 4; |
| 616 | pc++; |
| 617 | |
| 618 | /* If that's all, return now. */ |
| 619 | if (limit <= pc) |
| 620 | return limit; |
| 621 | |
| 622 | /* Check for some special instructions that might be migrated by |
| 623 | GCC into the prologue and skip them. At this point in the |
| 624 | prologue, code should only touch the scratch registers %eax, |
| 625 | %ecx and %edx, so while the number of posibilities is sheer, |
| 626 | it is limited. |
| 627 | |
| 628 | Make sure we only skip these instructions if we later see the |
| 629 | `movl %esp, %ebp' that actually sets up the frame. */ |
| 630 | while (pc + skip < limit) |
| 631 | { |
| 632 | insn = i386_match_insn (pc + skip, i386_frame_setup_skip_insns); |
| 633 | if (insn == NULL) |
| 634 | break; |
| 635 | |
| 636 | skip += insn->len; |
| 637 | } |
| 638 | |
| 639 | /* If that's all, return now. */ |
| 640 | if (limit <= pc + skip) |
| 641 | return limit; |
| 642 | |
| 643 | op = read_memory_unsigned_integer (pc + skip, 1); |
| 644 | |
| 645 | /* Check for `movl %esp, %ebp' -- can be written in two ways. */ |
| 646 | switch (op) |
| 647 | { |
| 648 | case 0x8b: |
| 649 | if (read_memory_unsigned_integer (pc + skip + 1, 1) != 0xec) |
| 650 | return pc; |
| 651 | break; |
| 652 | case 0x89: |
| 653 | if (read_memory_unsigned_integer (pc + skip + 1, 1) != 0xe5) |
| 654 | return pc; |
| 655 | break; |
| 656 | default: |
| 657 | return pc; |
| 658 | } |
| 659 | |
| 660 | /* OK, we actually have a frame. We just don't know how large |
| 661 | it is yet. Set its size to zero. We'll adjust it if |
| 662 | necessary. We also now commit to skipping the special |
| 663 | instructions mentioned before. */ |
| 664 | cache->locals = 0; |
| 665 | pc += (skip + 2); |
| 666 | |
| 667 | /* If that's all, return now. */ |
| 668 | if (limit <= pc) |
| 669 | return limit; |
| 670 | |
| 671 | /* Check for stack adjustment |
| 672 | |
| 673 | subl $XXX, %esp |
| 674 | |
| 675 | NOTE: You can't subtract a 16-bit immediate from a 32-bit |
| 676 | reg, so we don't have to worry about a data16 prefix. */ |
| 677 | op = read_memory_unsigned_integer (pc, 1); |
| 678 | if (op == 0x83) |
| 679 | { |
| 680 | /* `subl' with 8-bit immediate. */ |
| 681 | if (read_memory_unsigned_integer (pc + 1, 1) != 0xec) |
| 682 | /* Some instruction starting with 0x83 other than `subl'. */ |
| 683 | return pc; |
| 684 | |
| 685 | /* `subl' with signed 8-bit immediate (though it wouldn't |
| 686 | make sense to be negative). */ |
| 687 | cache->locals = read_memory_integer (pc + 2, 1); |
| 688 | return pc + 3; |
| 689 | } |
| 690 | else if (op == 0x81) |
| 691 | { |
| 692 | /* Maybe it is `subl' with a 32-bit immediate. */ |
| 693 | if (read_memory_unsigned_integer (pc + 1, 1) != 0xec) |
| 694 | /* Some instruction starting with 0x81 other than `subl'. */ |
| 695 | return pc; |
| 696 | |
| 697 | /* It is `subl' with a 32-bit immediate. */ |
| 698 | cache->locals = read_memory_integer (pc + 2, 4); |
| 699 | return pc + 6; |
| 700 | } |
| 701 | else |
| 702 | { |
| 703 | /* Some instruction other than `subl'. */ |
| 704 | return pc; |
| 705 | } |
| 706 | } |
| 707 | else if (op == 0xc8) /* enter */ |
| 708 | { |
| 709 | cache->locals = read_memory_unsigned_integer (pc + 1, 2); |
| 710 | return pc + 4; |
| 711 | } |
| 712 | |
| 713 | return pc; |
| 714 | } |
| 715 | |
| 716 | /* Check whether PC points at code that saves registers on the stack. |
| 717 | If so, it updates CACHE and returns the address of the first |
| 718 | instruction after the register saves or CURRENT_PC, whichever is |
| 719 | smaller. Otherwise, return PC. */ |
| 720 | |
| 721 | static CORE_ADDR |
| 722 | i386_analyze_register_saves (CORE_ADDR pc, CORE_ADDR current_pc, |
| 723 | struct i386_frame_cache *cache) |
| 724 | { |
| 725 | CORE_ADDR offset = 0; |
| 726 | gdb_byte op; |
| 727 | int i; |
| 728 | |
| 729 | if (cache->locals > 0) |
| 730 | offset -= cache->locals; |
| 731 | for (i = 0; i < 8 && pc < current_pc; i++) |
| 732 | { |
| 733 | op = read_memory_unsigned_integer (pc, 1); |
| 734 | if (op < 0x50 || op > 0x57) |
| 735 | break; |
| 736 | |
| 737 | offset -= 4; |
| 738 | cache->saved_regs[op - 0x50] = offset; |
| 739 | cache->sp_offset += 4; |
| 740 | pc++; |
| 741 | } |
| 742 | |
| 743 | return pc; |
| 744 | } |
| 745 | |
| 746 | /* Do a full analysis of the prologue at PC and update CACHE |
| 747 | accordingly. Bail out early if CURRENT_PC is reached. Return the |
| 748 | address where the analysis stopped. |
| 749 | |
| 750 | We handle these cases: |
| 751 | |
| 752 | The startup sequence can be at the start of the function, or the |
| 753 | function can start with a branch to startup code at the end. |
| 754 | |
| 755 | %ebp can be set up with either the 'enter' instruction, or "pushl |
| 756 | %ebp, movl %esp, %ebp" (`enter' is too slow to be useful, but was |
| 757 | once used in the System V compiler). |
| 758 | |
| 759 | Local space is allocated just below the saved %ebp by either the |
| 760 | 'enter' instruction, or by "subl $<size>, %esp". 'enter' has a |
| 761 | 16-bit unsigned argument for space to allocate, and the 'addl' |
| 762 | instruction could have either a signed byte, or 32-bit immediate. |
| 763 | |
| 764 | Next, the registers used by this function are pushed. With the |
| 765 | System V compiler they will always be in the order: %edi, %esi, |
| 766 | %ebx (and sometimes a harmless bug causes it to also save but not |
| 767 | restore %eax); however, the code below is willing to see the pushes |
| 768 | in any order, and will handle up to 8 of them. |
| 769 | |
| 770 | If the setup sequence is at the end of the function, then the next |
| 771 | instruction will be a branch back to the start. */ |
| 772 | |
| 773 | static CORE_ADDR |
| 774 | i386_analyze_prologue (CORE_ADDR pc, CORE_ADDR current_pc, |
| 775 | struct i386_frame_cache *cache) |
| 776 | { |
| 777 | pc = i386_follow_jump (pc); |
| 778 | pc = i386_analyze_struct_return (pc, current_pc, cache); |
| 779 | pc = i386_skip_probe (pc); |
| 780 | pc = i386_analyze_frame_setup (pc, current_pc, cache); |
| 781 | return i386_analyze_register_saves (pc, current_pc, cache); |
| 782 | } |
| 783 | |
| 784 | /* Return PC of first real instruction. */ |
| 785 | |
| 786 | static CORE_ADDR |
| 787 | i386_skip_prologue (CORE_ADDR start_pc) |
| 788 | { |
| 789 | static gdb_byte pic_pat[6] = |
| 790 | { |
| 791 | 0xe8, 0, 0, 0, 0, /* call 0x0 */ |
| 792 | 0x5b, /* popl %ebx */ |
| 793 | }; |
| 794 | struct i386_frame_cache cache; |
| 795 | CORE_ADDR pc; |
| 796 | gdb_byte op; |
| 797 | int i; |
| 798 | |
| 799 | cache.locals = -1; |
| 800 | pc = i386_analyze_prologue (start_pc, 0xffffffff, &cache); |
| 801 | if (cache.locals < 0) |
| 802 | return start_pc; |
| 803 | |
| 804 | /* Found valid frame setup. */ |
| 805 | |
| 806 | /* The native cc on SVR4 in -K PIC mode inserts the following code |
| 807 | to get the address of the global offset table (GOT) into register |
| 808 | %ebx: |
| 809 | |
| 810 | call 0x0 |
| 811 | popl %ebx |
| 812 | movl %ebx,x(%ebp) (optional) |
| 813 | addl y,%ebx |
| 814 | |
| 815 | This code is with the rest of the prologue (at the end of the |
| 816 | function), so we have to skip it to get to the first real |
| 817 | instruction at the start of the function. */ |
| 818 | |
| 819 | for (i = 0; i < 6; i++) |
| 820 | { |
| 821 | op = read_memory_unsigned_integer (pc + i, 1); |
| 822 | if (pic_pat[i] != op) |
| 823 | break; |
| 824 | } |
| 825 | if (i == 6) |
| 826 | { |
| 827 | int delta = 6; |
| 828 | |
| 829 | op = read_memory_unsigned_integer (pc + delta, 1); |
| 830 | |
| 831 | if (op == 0x89) /* movl %ebx, x(%ebp) */ |
| 832 | { |
| 833 | op = read_memory_unsigned_integer (pc + delta + 1, 1); |
| 834 | |
| 835 | if (op == 0x5d) /* One byte offset from %ebp. */ |
| 836 | delta += 3; |
| 837 | else if (op == 0x9d) /* Four byte offset from %ebp. */ |
| 838 | delta += 6; |
| 839 | else /* Unexpected instruction. */ |
| 840 | delta = 0; |
| 841 | |
| 842 | op = read_memory_unsigned_integer (pc + delta, 1); |
| 843 | } |
| 844 | |
| 845 | /* addl y,%ebx */ |
| 846 | if (delta > 0 && op == 0x81 |
| 847 | && read_memory_unsigned_integer (pc + delta + 1, 1) == 0xc3); |
| 848 | { |
| 849 | pc += delta + 6; |
| 850 | } |
| 851 | } |
| 852 | |
| 853 | /* If the function starts with a branch (to startup code at the end) |
| 854 | the last instruction should bring us back to the first |
| 855 | instruction of the real code. */ |
| 856 | if (i386_follow_jump (start_pc) != start_pc) |
| 857 | pc = i386_follow_jump (pc); |
| 858 | |
| 859 | return pc; |
| 860 | } |
| 861 | |
| 862 | /* This function is 64-bit safe. */ |
| 863 | |
| 864 | static CORE_ADDR |
| 865 | i386_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame) |
| 866 | { |
| 867 | gdb_byte buf[8]; |
| 868 | |
| 869 | frame_unwind_register (next_frame, PC_REGNUM, buf); |
| 870 | return extract_typed_address (buf, builtin_type_void_func_ptr); |
| 871 | } |
| 872 | \f |
| 873 | |
| 874 | /* Normal frames. */ |
| 875 | |
| 876 | static struct i386_frame_cache * |
| 877 | i386_frame_cache (struct frame_info *next_frame, void **this_cache) |
| 878 | { |
| 879 | struct i386_frame_cache *cache; |
| 880 | gdb_byte buf[4]; |
| 881 | int i; |
| 882 | |
| 883 | if (*this_cache) |
| 884 | return *this_cache; |
| 885 | |
| 886 | cache = i386_alloc_frame_cache (); |
| 887 | *this_cache = cache; |
| 888 | |
| 889 | /* In principle, for normal frames, %ebp holds the frame pointer, |
| 890 | which holds the base address for the current stack frame. |
| 891 | However, for functions that don't need it, the frame pointer is |
| 892 | optional. For these "frameless" functions the frame pointer is |
| 893 | actually the frame pointer of the calling frame. Signal |
| 894 | trampolines are just a special case of a "frameless" function. |
| 895 | They (usually) share their frame pointer with the frame that was |
| 896 | in progress when the signal occurred. */ |
| 897 | |
| 898 | frame_unwind_register (next_frame, I386_EBP_REGNUM, buf); |
| 899 | cache->base = extract_unsigned_integer (buf, 4); |
| 900 | if (cache->base == 0) |
| 901 | return cache; |
| 902 | |
| 903 | /* For normal frames, %eip is stored at 4(%ebp). */ |
| 904 | cache->saved_regs[I386_EIP_REGNUM] = 4; |
| 905 | |
| 906 | cache->pc = frame_func_unwind (next_frame); |
| 907 | if (cache->pc != 0) |
| 908 | i386_analyze_prologue (cache->pc, frame_pc_unwind (next_frame), cache); |
| 909 | |
| 910 | if (cache->locals < 0) |
| 911 | { |
| 912 | /* We didn't find a valid frame, which means that CACHE->base |
| 913 | currently holds the frame pointer for our calling frame. If |
| 914 | we're at the start of a function, or somewhere half-way its |
| 915 | prologue, the function's frame probably hasn't been fully |
| 916 | setup yet. Try to reconstruct the base address for the stack |
| 917 | frame by looking at the stack pointer. For truly "frameless" |
| 918 | functions this might work too. */ |
| 919 | |
| 920 | frame_unwind_register (next_frame, I386_ESP_REGNUM, buf); |
| 921 | cache->base = extract_unsigned_integer (buf, 4) + cache->sp_offset; |
| 922 | } |
| 923 | |
| 924 | /* Now that we have the base address for the stack frame we can |
| 925 | calculate the value of %esp in the calling frame. */ |
| 926 | cache->saved_sp = cache->base + 8; |
| 927 | |
| 928 | /* Adjust all the saved registers such that they contain addresses |
| 929 | instead of offsets. */ |
| 930 | for (i = 0; i < I386_NUM_SAVED_REGS; i++) |
| 931 | if (cache->saved_regs[i] != -1) |
| 932 | cache->saved_regs[i] += cache->base; |
| 933 | |
| 934 | return cache; |
| 935 | } |
| 936 | |
| 937 | static void |
| 938 | i386_frame_this_id (struct frame_info *next_frame, void **this_cache, |
| 939 | struct frame_id *this_id) |
| 940 | { |
| 941 | struct i386_frame_cache *cache = i386_frame_cache (next_frame, this_cache); |
| 942 | |
| 943 | /* This marks the outermost frame. */ |
| 944 | if (cache->base == 0) |
| 945 | return; |
| 946 | |
| 947 | /* See the end of i386_push_dummy_call. */ |
| 948 | (*this_id) = frame_id_build (cache->base + 8, cache->pc); |
| 949 | } |
| 950 | |
| 951 | static void |
| 952 | i386_frame_prev_register (struct frame_info *next_frame, void **this_cache, |
| 953 | int regnum, int *optimizedp, |
| 954 | enum lval_type *lvalp, CORE_ADDR *addrp, |
| 955 | int *realnump, gdb_byte *valuep) |
| 956 | { |
| 957 | struct i386_frame_cache *cache = i386_frame_cache (next_frame, this_cache); |
| 958 | |
| 959 | gdb_assert (regnum >= 0); |
| 960 | |
| 961 | /* The System V ABI says that: |
| 962 | |
| 963 | "The flags register contains the system flags, such as the |
| 964 | direction flag and the carry flag. The direction flag must be |
| 965 | set to the forward (that is, zero) direction before entry and |
| 966 | upon exit from a function. Other user flags have no specified |
| 967 | role in the standard calling sequence and are not preserved." |
| 968 | |
| 969 | To guarantee the "upon exit" part of that statement we fake a |
| 970 | saved flags register that has its direction flag cleared. |
| 971 | |
| 972 | Note that GCC doesn't seem to rely on the fact that the direction |
| 973 | flag is cleared after a function return; it always explicitly |
| 974 | clears the flag before operations where it matters. |
| 975 | |
| 976 | FIXME: kettenis/20030316: I'm not quite sure whether this is the |
| 977 | right thing to do. The way we fake the flags register here makes |
| 978 | it impossible to change it. */ |
| 979 | |
| 980 | if (regnum == I386_EFLAGS_REGNUM) |
| 981 | { |
| 982 | *optimizedp = 0; |
| 983 | *lvalp = not_lval; |
| 984 | *addrp = 0; |
| 985 | *realnump = -1; |
| 986 | if (valuep) |
| 987 | { |
| 988 | ULONGEST val; |
| 989 | |
| 990 | /* Clear the direction flag. */ |
| 991 | val = frame_unwind_register_unsigned (next_frame, |
| 992 | I386_EFLAGS_REGNUM); |
| 993 | val &= ~(1 << 10); |
| 994 | store_unsigned_integer (valuep, 4, val); |
| 995 | } |
| 996 | |
| 997 | return; |
| 998 | } |
| 999 | |
| 1000 | if (regnum == I386_EIP_REGNUM && cache->pc_in_eax) |
| 1001 | { |
| 1002 | *optimizedp = 0; |
| 1003 | *lvalp = lval_register; |
| 1004 | *addrp = 0; |
| 1005 | *realnump = I386_EAX_REGNUM; |
| 1006 | if (valuep) |
| 1007 | frame_unwind_register (next_frame, (*realnump), valuep); |
| 1008 | return; |
| 1009 | } |
| 1010 | |
| 1011 | if (regnum == I386_ESP_REGNUM && cache->saved_sp) |
| 1012 | { |
| 1013 | *optimizedp = 0; |
| 1014 | *lvalp = not_lval; |
| 1015 | *addrp = 0; |
| 1016 | *realnump = -1; |
| 1017 | if (valuep) |
| 1018 | { |
| 1019 | /* Store the value. */ |
| 1020 | store_unsigned_integer (valuep, 4, cache->saved_sp); |
| 1021 | } |
| 1022 | return; |
| 1023 | } |
| 1024 | |
| 1025 | if (regnum < I386_NUM_SAVED_REGS && cache->saved_regs[regnum] != -1) |
| 1026 | { |
| 1027 | *optimizedp = 0; |
| 1028 | *lvalp = lval_memory; |
| 1029 | *addrp = cache->saved_regs[regnum]; |
| 1030 | *realnump = -1; |
| 1031 | if (valuep) |
| 1032 | { |
| 1033 | /* Read the value in from memory. */ |
| 1034 | read_memory (*addrp, valuep, |
| 1035 | register_size (current_gdbarch, regnum)); |
| 1036 | } |
| 1037 | return; |
| 1038 | } |
| 1039 | |
| 1040 | *optimizedp = 0; |
| 1041 | *lvalp = lval_register; |
| 1042 | *addrp = 0; |
| 1043 | *realnump = regnum; |
| 1044 | if (valuep) |
| 1045 | frame_unwind_register (next_frame, (*realnump), valuep); |
| 1046 | } |
| 1047 | |
| 1048 | static const struct frame_unwind i386_frame_unwind = |
| 1049 | { |
| 1050 | NORMAL_FRAME, |
| 1051 | i386_frame_this_id, |
| 1052 | i386_frame_prev_register |
| 1053 | }; |
| 1054 | |
| 1055 | static const struct frame_unwind * |
| 1056 | i386_frame_sniffer (struct frame_info *next_frame) |
| 1057 | { |
| 1058 | return &i386_frame_unwind; |
| 1059 | } |
| 1060 | \f |
| 1061 | |
| 1062 | /* Signal trampolines. */ |
| 1063 | |
| 1064 | static struct i386_frame_cache * |
| 1065 | i386_sigtramp_frame_cache (struct frame_info *next_frame, void **this_cache) |
| 1066 | { |
| 1067 | struct i386_frame_cache *cache; |
| 1068 | struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch); |
| 1069 | CORE_ADDR addr; |
| 1070 | gdb_byte buf[4]; |
| 1071 | |
| 1072 | if (*this_cache) |
| 1073 | return *this_cache; |
| 1074 | |
| 1075 | cache = i386_alloc_frame_cache (); |
| 1076 | |
| 1077 | frame_unwind_register (next_frame, I386_ESP_REGNUM, buf); |
| 1078 | cache->base = extract_unsigned_integer (buf, 4) - 4; |
| 1079 | |
| 1080 | addr = tdep->sigcontext_addr (next_frame); |
| 1081 | if (tdep->sc_reg_offset) |
| 1082 | { |
| 1083 | int i; |
| 1084 | |
| 1085 | gdb_assert (tdep->sc_num_regs <= I386_NUM_SAVED_REGS); |
| 1086 | |
| 1087 | for (i = 0; i < tdep->sc_num_regs; i++) |
| 1088 | if (tdep->sc_reg_offset[i] != -1) |
| 1089 | cache->saved_regs[i] = addr + tdep->sc_reg_offset[i]; |
| 1090 | } |
| 1091 | else |
| 1092 | { |
| 1093 | cache->saved_regs[I386_EIP_REGNUM] = addr + tdep->sc_pc_offset; |
| 1094 | cache->saved_regs[I386_ESP_REGNUM] = addr + tdep->sc_sp_offset; |
| 1095 | } |
| 1096 | |
| 1097 | *this_cache = cache; |
| 1098 | return cache; |
| 1099 | } |
| 1100 | |
| 1101 | static void |
| 1102 | i386_sigtramp_frame_this_id (struct frame_info *next_frame, void **this_cache, |
| 1103 | struct frame_id *this_id) |
| 1104 | { |
| 1105 | struct i386_frame_cache *cache = |
| 1106 | i386_sigtramp_frame_cache (next_frame, this_cache); |
| 1107 | |
| 1108 | /* See the end of i386_push_dummy_call. */ |
| 1109 | (*this_id) = frame_id_build (cache->base + 8, frame_pc_unwind (next_frame)); |
| 1110 | } |
| 1111 | |
| 1112 | static void |
| 1113 | i386_sigtramp_frame_prev_register (struct frame_info *next_frame, |
| 1114 | void **this_cache, |
| 1115 | int regnum, int *optimizedp, |
| 1116 | enum lval_type *lvalp, CORE_ADDR *addrp, |
| 1117 | int *realnump, gdb_byte *valuep) |
| 1118 | { |
| 1119 | /* Make sure we've initialized the cache. */ |
| 1120 | i386_sigtramp_frame_cache (next_frame, this_cache); |
| 1121 | |
| 1122 | i386_frame_prev_register (next_frame, this_cache, regnum, |
| 1123 | optimizedp, lvalp, addrp, realnump, valuep); |
| 1124 | } |
| 1125 | |
| 1126 | static const struct frame_unwind i386_sigtramp_frame_unwind = |
| 1127 | { |
| 1128 | SIGTRAMP_FRAME, |
| 1129 | i386_sigtramp_frame_this_id, |
| 1130 | i386_sigtramp_frame_prev_register |
| 1131 | }; |
| 1132 | |
| 1133 | static const struct frame_unwind * |
| 1134 | i386_sigtramp_frame_sniffer (struct frame_info *next_frame) |
| 1135 | { |
| 1136 | struct gdbarch_tdep *tdep = gdbarch_tdep (get_frame_arch (next_frame)); |
| 1137 | |
| 1138 | /* We shouldn't even bother if we don't have a sigcontext_addr |
| 1139 | handler. */ |
| 1140 | if (tdep->sigcontext_addr == NULL) |
| 1141 | return NULL; |
| 1142 | |
| 1143 | if (tdep->sigtramp_p != NULL) |
| 1144 | { |
| 1145 | if (tdep->sigtramp_p (next_frame)) |
| 1146 | return &i386_sigtramp_frame_unwind; |
| 1147 | } |
| 1148 | |
| 1149 | if (tdep->sigtramp_start != 0) |
| 1150 | { |
| 1151 | CORE_ADDR pc = frame_pc_unwind (next_frame); |
| 1152 | |
| 1153 | gdb_assert (tdep->sigtramp_end != 0); |
| 1154 | if (pc >= tdep->sigtramp_start && pc < tdep->sigtramp_end) |
| 1155 | return &i386_sigtramp_frame_unwind; |
| 1156 | } |
| 1157 | |
| 1158 | return NULL; |
| 1159 | } |
| 1160 | \f |
| 1161 | |
| 1162 | static CORE_ADDR |
| 1163 | i386_frame_base_address (struct frame_info *next_frame, void **this_cache) |
| 1164 | { |
| 1165 | struct i386_frame_cache *cache = i386_frame_cache (next_frame, this_cache); |
| 1166 | |
| 1167 | return cache->base; |
| 1168 | } |
| 1169 | |
| 1170 | static const struct frame_base i386_frame_base = |
| 1171 | { |
| 1172 | &i386_frame_unwind, |
| 1173 | i386_frame_base_address, |
| 1174 | i386_frame_base_address, |
| 1175 | i386_frame_base_address |
| 1176 | }; |
| 1177 | |
| 1178 | static struct frame_id |
| 1179 | i386_unwind_dummy_id (struct gdbarch *gdbarch, struct frame_info *next_frame) |
| 1180 | { |
| 1181 | gdb_byte buf[4]; |
| 1182 | CORE_ADDR fp; |
| 1183 | |
| 1184 | frame_unwind_register (next_frame, I386_EBP_REGNUM, buf); |
| 1185 | fp = extract_unsigned_integer (buf, 4); |
| 1186 | |
| 1187 | /* See the end of i386_push_dummy_call. */ |
| 1188 | return frame_id_build (fp + 8, frame_pc_unwind (next_frame)); |
| 1189 | } |
| 1190 | \f |
| 1191 | |
| 1192 | /* Figure out where the longjmp will land. Slurp the args out of the |
| 1193 | stack. We expect the first arg to be a pointer to the jmp_buf |
| 1194 | structure from which we extract the address that we will land at. |
| 1195 | This address is copied into PC. This routine returns non-zero on |
| 1196 | success. |
| 1197 | |
| 1198 | This function is 64-bit safe. */ |
| 1199 | |
| 1200 | static int |
| 1201 | i386_get_longjmp_target (CORE_ADDR *pc) |
| 1202 | { |
| 1203 | gdb_byte buf[8]; |
| 1204 | CORE_ADDR sp, jb_addr; |
| 1205 | int jb_pc_offset = gdbarch_tdep (current_gdbarch)->jb_pc_offset; |
| 1206 | int len = TYPE_LENGTH (builtin_type_void_func_ptr); |
| 1207 | |
| 1208 | /* If JB_PC_OFFSET is -1, we have no way to find out where the |
| 1209 | longjmp will land. */ |
| 1210 | if (jb_pc_offset == -1) |
| 1211 | return 0; |
| 1212 | |
| 1213 | /* Don't use I386_ESP_REGNUM here, since this function is also used |
| 1214 | for AMD64. */ |
| 1215 | regcache_cooked_read (current_regcache, SP_REGNUM, buf); |
| 1216 | sp = extract_typed_address (buf, builtin_type_void_data_ptr); |
| 1217 | if (target_read_memory (sp + len, buf, len)) |
| 1218 | return 0; |
| 1219 | |
| 1220 | jb_addr = extract_typed_address (buf, builtin_type_void_data_ptr); |
| 1221 | if (target_read_memory (jb_addr + jb_pc_offset, buf, len)) |
| 1222 | return 0; |
| 1223 | |
| 1224 | *pc = extract_typed_address (buf, builtin_type_void_func_ptr); |
| 1225 | return 1; |
| 1226 | } |
| 1227 | \f |
| 1228 | |
| 1229 | static CORE_ADDR |
| 1230 | i386_push_dummy_call (struct gdbarch *gdbarch, struct value *function, |
| 1231 | struct regcache *regcache, CORE_ADDR bp_addr, int nargs, |
| 1232 | struct value **args, CORE_ADDR sp, int struct_return, |
| 1233 | CORE_ADDR struct_addr) |
| 1234 | { |
| 1235 | gdb_byte buf[4]; |
| 1236 | int i; |
| 1237 | |
| 1238 | /* Push arguments in reverse order. */ |
| 1239 | for (i = nargs - 1; i >= 0; i--) |
| 1240 | { |
| 1241 | int len = TYPE_LENGTH (value_enclosing_type (args[i])); |
| 1242 | |
| 1243 | /* The System V ABI says that: |
| 1244 | |
| 1245 | "An argument's size is increased, if necessary, to make it a |
| 1246 | multiple of [32-bit] words. This may require tail padding, |
| 1247 | depending on the size of the argument." |
| 1248 | |
| 1249 | This makes sure the stack says word-aligned. */ |
| 1250 | sp -= (len + 3) & ~3; |
| 1251 | write_memory (sp, value_contents_all (args[i]), len); |
| 1252 | } |
| 1253 | |
| 1254 | /* Push value address. */ |
| 1255 | if (struct_return) |
| 1256 | { |
| 1257 | sp -= 4; |
| 1258 | store_unsigned_integer (buf, 4, struct_addr); |
| 1259 | write_memory (sp, buf, 4); |
| 1260 | } |
| 1261 | |
| 1262 | /* Store return address. */ |
| 1263 | sp -= 4; |
| 1264 | store_unsigned_integer (buf, 4, bp_addr); |
| 1265 | write_memory (sp, buf, 4); |
| 1266 | |
| 1267 | /* Finally, update the stack pointer... */ |
| 1268 | store_unsigned_integer (buf, 4, sp); |
| 1269 | regcache_cooked_write (regcache, I386_ESP_REGNUM, buf); |
| 1270 | |
| 1271 | /* ...and fake a frame pointer. */ |
| 1272 | regcache_cooked_write (regcache, I386_EBP_REGNUM, buf); |
| 1273 | |
| 1274 | /* MarkK wrote: This "+ 8" is all over the place: |
| 1275 | (i386_frame_this_id, i386_sigtramp_frame_this_id, |
| 1276 | i386_unwind_dummy_id). It's there, since all frame unwinders for |
| 1277 | a given target have to agree (within a certain margin) on the |
| 1278 | definition of the stack address of a frame. Otherwise |
| 1279 | frame_id_inner() won't work correctly. Since DWARF2/GCC uses the |
| 1280 | stack address *before* the function call as a frame's CFA. On |
| 1281 | the i386, when %ebp is used as a frame pointer, the offset |
| 1282 | between the contents %ebp and the CFA as defined by GCC. */ |
| 1283 | return sp + 8; |
| 1284 | } |
| 1285 | |
| 1286 | /* These registers are used for returning integers (and on some |
| 1287 | targets also for returning `struct' and `union' values when their |
| 1288 | size and alignment match an integer type). */ |
| 1289 | #define LOW_RETURN_REGNUM I386_EAX_REGNUM /* %eax */ |
| 1290 | #define HIGH_RETURN_REGNUM I386_EDX_REGNUM /* %edx */ |
| 1291 | |
| 1292 | /* Read, for architecture GDBARCH, a function return value of TYPE |
| 1293 | from REGCACHE, and copy that into VALBUF. */ |
| 1294 | |
| 1295 | static void |
| 1296 | i386_extract_return_value (struct gdbarch *gdbarch, struct type *type, |
| 1297 | struct regcache *regcache, gdb_byte *valbuf) |
| 1298 | { |
| 1299 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 1300 | int len = TYPE_LENGTH (type); |
| 1301 | gdb_byte buf[I386_MAX_REGISTER_SIZE]; |
| 1302 | |
| 1303 | if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| 1304 | { |
| 1305 | if (tdep->st0_regnum < 0) |
| 1306 | { |
| 1307 | warning (_("Cannot find floating-point return value.")); |
| 1308 | memset (valbuf, 0, len); |
| 1309 | return; |
| 1310 | } |
| 1311 | |
| 1312 | /* Floating-point return values can be found in %st(0). Convert |
| 1313 | its contents to the desired type. This is probably not |
| 1314 | exactly how it would happen on the target itself, but it is |
| 1315 | the best we can do. */ |
| 1316 | regcache_raw_read (regcache, I386_ST0_REGNUM, buf); |
| 1317 | convert_typed_floating (buf, builtin_type_i387_ext, valbuf, type); |
| 1318 | } |
| 1319 | else |
| 1320 | { |
| 1321 | int low_size = register_size (current_gdbarch, LOW_RETURN_REGNUM); |
| 1322 | int high_size = register_size (current_gdbarch, HIGH_RETURN_REGNUM); |
| 1323 | |
| 1324 | if (len <= low_size) |
| 1325 | { |
| 1326 | regcache_raw_read (regcache, LOW_RETURN_REGNUM, buf); |
| 1327 | memcpy (valbuf, buf, len); |
| 1328 | } |
| 1329 | else if (len <= (low_size + high_size)) |
| 1330 | { |
| 1331 | regcache_raw_read (regcache, LOW_RETURN_REGNUM, buf); |
| 1332 | memcpy (valbuf, buf, low_size); |
| 1333 | regcache_raw_read (regcache, HIGH_RETURN_REGNUM, buf); |
| 1334 | memcpy (valbuf + low_size, buf, len - low_size); |
| 1335 | } |
| 1336 | else |
| 1337 | internal_error (__FILE__, __LINE__, |
| 1338 | _("Cannot extract return value of %d bytes long."), len); |
| 1339 | } |
| 1340 | } |
| 1341 | |
| 1342 | /* Write, for architecture GDBARCH, a function return value of TYPE |
| 1343 | from VALBUF into REGCACHE. */ |
| 1344 | |
| 1345 | static void |
| 1346 | i386_store_return_value (struct gdbarch *gdbarch, struct type *type, |
| 1347 | struct regcache *regcache, const gdb_byte *valbuf) |
| 1348 | { |
| 1349 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 1350 | int len = TYPE_LENGTH (type); |
| 1351 | |
| 1352 | /* Define I387_ST0_REGNUM such that we use the proper definitions |
| 1353 | for the architecture. */ |
| 1354 | #define I387_ST0_REGNUM I386_ST0_REGNUM |
| 1355 | |
| 1356 | if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| 1357 | { |
| 1358 | ULONGEST fstat; |
| 1359 | gdb_byte buf[I386_MAX_REGISTER_SIZE]; |
| 1360 | |
| 1361 | if (tdep->st0_regnum < 0) |
| 1362 | { |
| 1363 | warning (_("Cannot set floating-point return value.")); |
| 1364 | return; |
| 1365 | } |
| 1366 | |
| 1367 | /* Returning floating-point values is a bit tricky. Apart from |
| 1368 | storing the return value in %st(0), we have to simulate the |
| 1369 | state of the FPU at function return point. */ |
| 1370 | |
| 1371 | /* Convert the value found in VALBUF to the extended |
| 1372 | floating-point format used by the FPU. This is probably |
| 1373 | not exactly how it would happen on the target itself, but |
| 1374 | it is the best we can do. */ |
| 1375 | convert_typed_floating (valbuf, type, buf, builtin_type_i387_ext); |
| 1376 | regcache_raw_write (regcache, I386_ST0_REGNUM, buf); |
| 1377 | |
| 1378 | /* Set the top of the floating-point register stack to 7. The |
| 1379 | actual value doesn't really matter, but 7 is what a normal |
| 1380 | function return would end up with if the program started out |
| 1381 | with a freshly initialized FPU. */ |
| 1382 | regcache_raw_read_unsigned (regcache, I387_FSTAT_REGNUM, &fstat); |
| 1383 | fstat |= (7 << 11); |
| 1384 | regcache_raw_write_unsigned (regcache, I387_FSTAT_REGNUM, fstat); |
| 1385 | |
| 1386 | /* Mark %st(1) through %st(7) as empty. Since we set the top of |
| 1387 | the floating-point register stack to 7, the appropriate value |
| 1388 | for the tag word is 0x3fff. */ |
| 1389 | regcache_raw_write_unsigned (regcache, I387_FTAG_REGNUM, 0x3fff); |
| 1390 | } |
| 1391 | else |
| 1392 | { |
| 1393 | int low_size = register_size (current_gdbarch, LOW_RETURN_REGNUM); |
| 1394 | int high_size = register_size (current_gdbarch, HIGH_RETURN_REGNUM); |
| 1395 | |
| 1396 | if (len <= low_size) |
| 1397 | regcache_raw_write_part (regcache, LOW_RETURN_REGNUM, 0, len, valbuf); |
| 1398 | else if (len <= (low_size + high_size)) |
| 1399 | { |
| 1400 | regcache_raw_write (regcache, LOW_RETURN_REGNUM, valbuf); |
| 1401 | regcache_raw_write_part (regcache, HIGH_RETURN_REGNUM, 0, |
| 1402 | len - low_size, valbuf + low_size); |
| 1403 | } |
| 1404 | else |
| 1405 | internal_error (__FILE__, __LINE__, |
| 1406 | _("Cannot store return value of %d bytes long."), len); |
| 1407 | } |
| 1408 | |
| 1409 | #undef I387_ST0_REGNUM |
| 1410 | } |
| 1411 | \f |
| 1412 | |
| 1413 | /* This is the variable that is set with "set struct-convention", and |
| 1414 | its legitimate values. */ |
| 1415 | static const char default_struct_convention[] = "default"; |
| 1416 | static const char pcc_struct_convention[] = "pcc"; |
| 1417 | static const char reg_struct_convention[] = "reg"; |
| 1418 | static const char *valid_conventions[] = |
| 1419 | { |
| 1420 | default_struct_convention, |
| 1421 | pcc_struct_convention, |
| 1422 | reg_struct_convention, |
| 1423 | NULL |
| 1424 | }; |
| 1425 | static const char *struct_convention = default_struct_convention; |
| 1426 | |
| 1427 | /* Return non-zero if TYPE, which is assumed to be a structure or |
| 1428 | union type, should be returned in registers for architecture |
| 1429 | GDBARCH. */ |
| 1430 | |
| 1431 | static int |
| 1432 | i386_reg_struct_return_p (struct gdbarch *gdbarch, struct type *type) |
| 1433 | { |
| 1434 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 1435 | enum type_code code = TYPE_CODE (type); |
| 1436 | int len = TYPE_LENGTH (type); |
| 1437 | |
| 1438 | gdb_assert (code == TYPE_CODE_STRUCT || code == TYPE_CODE_UNION); |
| 1439 | |
| 1440 | if (struct_convention == pcc_struct_convention |
| 1441 | || (struct_convention == default_struct_convention |
| 1442 | && tdep->struct_return == pcc_struct_return)) |
| 1443 | return 0; |
| 1444 | |
| 1445 | /* Structures consisting of a single `float', `double' or 'long |
| 1446 | double' member are returned in %st(0). */ |
| 1447 | if (code == TYPE_CODE_STRUCT && TYPE_NFIELDS (type) == 1) |
| 1448 | { |
| 1449 | type = check_typedef (TYPE_FIELD_TYPE (type, 0)); |
| 1450 | if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| 1451 | return (len == 4 || len == 8 || len == 12); |
| 1452 | } |
| 1453 | |
| 1454 | return (len == 1 || len == 2 || len == 4 || len == 8); |
| 1455 | } |
| 1456 | |
| 1457 | /* Determine, for architecture GDBARCH, how a return value of TYPE |
| 1458 | should be returned. If it is supposed to be returned in registers, |
| 1459 | and READBUF is non-zero, read the appropriate value from REGCACHE, |
| 1460 | and copy it into READBUF. If WRITEBUF is non-zero, write the value |
| 1461 | from WRITEBUF into REGCACHE. */ |
| 1462 | |
| 1463 | static enum return_value_convention |
| 1464 | i386_return_value (struct gdbarch *gdbarch, struct type *type, |
| 1465 | struct regcache *regcache, gdb_byte *readbuf, |
| 1466 | const gdb_byte *writebuf) |
| 1467 | { |
| 1468 | enum type_code code = TYPE_CODE (type); |
| 1469 | |
| 1470 | if ((code == TYPE_CODE_STRUCT || code == TYPE_CODE_UNION) |
| 1471 | && !i386_reg_struct_return_p (gdbarch, type)) |
| 1472 | { |
| 1473 | /* The System V ABI says that: |
| 1474 | |
| 1475 | "A function that returns a structure or union also sets %eax |
| 1476 | to the value of the original address of the caller's area |
| 1477 | before it returns. Thus when the caller receives control |
| 1478 | again, the address of the returned object resides in register |
| 1479 | %eax and can be used to access the object." |
| 1480 | |
| 1481 | So the ABI guarantees that we can always find the return |
| 1482 | value just after the function has returned. */ |
| 1483 | |
| 1484 | if (readbuf) |
| 1485 | { |
| 1486 | ULONGEST addr; |
| 1487 | |
| 1488 | regcache_raw_read_unsigned (regcache, I386_EAX_REGNUM, &addr); |
| 1489 | read_memory (addr, readbuf, TYPE_LENGTH (type)); |
| 1490 | } |
| 1491 | |
| 1492 | return RETURN_VALUE_ABI_RETURNS_ADDRESS; |
| 1493 | } |
| 1494 | |
| 1495 | /* This special case is for structures consisting of a single |
| 1496 | `float', `double' or 'long double' member. These structures are |
| 1497 | returned in %st(0). For these structures, we call ourselves |
| 1498 | recursively, changing TYPE into the type of the first member of |
| 1499 | the structure. Since that should work for all structures that |
| 1500 | have only one member, we don't bother to check the member's type |
| 1501 | here. */ |
| 1502 | if (code == TYPE_CODE_STRUCT && TYPE_NFIELDS (type) == 1) |
| 1503 | { |
| 1504 | type = check_typedef (TYPE_FIELD_TYPE (type, 0)); |
| 1505 | return i386_return_value (gdbarch, type, regcache, readbuf, writebuf); |
| 1506 | } |
| 1507 | |
| 1508 | if (readbuf) |
| 1509 | i386_extract_return_value (gdbarch, type, regcache, readbuf); |
| 1510 | if (writebuf) |
| 1511 | i386_store_return_value (gdbarch, type, regcache, writebuf); |
| 1512 | |
| 1513 | return RETURN_VALUE_REGISTER_CONVENTION; |
| 1514 | } |
| 1515 | \f |
| 1516 | |
| 1517 | /* Types for the MMX and SSE registers. */ |
| 1518 | static struct type *i386_mmx_type; |
| 1519 | static struct type *i386_sse_type; |
| 1520 | |
| 1521 | /* Construct the type for MMX registers. */ |
| 1522 | static struct type * |
| 1523 | i386_build_mmx_type (void) |
| 1524 | { |
| 1525 | /* The type we're building is this: */ |
| 1526 | #if 0 |
| 1527 | union __gdb_builtin_type_vec64i |
| 1528 | { |
| 1529 | int64_t uint64; |
| 1530 | int32_t v2_int32[2]; |
| 1531 | int16_t v4_int16[4]; |
| 1532 | int8_t v8_int8[8]; |
| 1533 | }; |
| 1534 | #endif |
| 1535 | |
| 1536 | if (! i386_mmx_type) |
| 1537 | { |
| 1538 | struct type *t; |
| 1539 | |
| 1540 | t = init_composite_type ("__gdb_builtin_type_vec64i", TYPE_CODE_UNION); |
| 1541 | append_composite_type_field (t, "uint64", builtin_type_int64); |
| 1542 | append_composite_type_field (t, "v2_int32", builtin_type_v2_int32); |
| 1543 | append_composite_type_field (t, "v4_int16", builtin_type_v4_int16); |
| 1544 | append_composite_type_field (t, "v8_int8", builtin_type_v8_int8); |
| 1545 | |
| 1546 | TYPE_FLAGS (t) |= TYPE_FLAG_VECTOR; |
| 1547 | TYPE_NAME (t) = "builtin_type_vec64i"; |
| 1548 | |
| 1549 | i386_mmx_type = t; |
| 1550 | } |
| 1551 | |
| 1552 | return i386_mmx_type; |
| 1553 | } |
| 1554 | |
| 1555 | /* Construct the type for SSE registers. */ |
| 1556 | static struct type * |
| 1557 | i386_build_sse_type (void) |
| 1558 | { |
| 1559 | if (! i386_sse_type) |
| 1560 | { |
| 1561 | struct type *t; |
| 1562 | |
| 1563 | t = init_composite_type ("__gdb_builtin_type_vec128i", TYPE_CODE_UNION); |
| 1564 | append_composite_type_field (t, "v4_float", builtin_type_v4_float); |
| 1565 | append_composite_type_field (t, "v2_double", builtin_type_v2_double); |
| 1566 | append_composite_type_field (t, "v16_int8", builtin_type_v16_int8); |
| 1567 | append_composite_type_field (t, "v8_int16", builtin_type_v8_int16); |
| 1568 | append_composite_type_field (t, "v4_int32", builtin_type_v4_int32); |
| 1569 | append_composite_type_field (t, "v2_int64", builtin_type_v2_int64); |
| 1570 | append_composite_type_field (t, "uint128", builtin_type_int128); |
| 1571 | |
| 1572 | TYPE_FLAGS (t) |= TYPE_FLAG_VECTOR; |
| 1573 | TYPE_NAME (t) = "builtin_type_vec128i"; |
| 1574 | |
| 1575 | i386_sse_type = t; |
| 1576 | } |
| 1577 | |
| 1578 | return i386_sse_type; |
| 1579 | } |
| 1580 | |
| 1581 | /* Return the GDB type object for the "standard" data type of data in |
| 1582 | register REGNUM. Perhaps %esi and %edi should go here, but |
| 1583 | potentially they could be used for things other than address. */ |
| 1584 | |
| 1585 | static struct type * |
| 1586 | i386_register_type (struct gdbarch *gdbarch, int regnum) |
| 1587 | { |
| 1588 | if (regnum == I386_EIP_REGNUM) |
| 1589 | return builtin_type_void_func_ptr; |
| 1590 | |
| 1591 | if (regnum == I386_EBP_REGNUM || regnum == I386_ESP_REGNUM) |
| 1592 | return builtin_type_void_data_ptr; |
| 1593 | |
| 1594 | if (i386_fp_regnum_p (regnum)) |
| 1595 | return builtin_type_i387_ext; |
| 1596 | |
| 1597 | if (i386_sse_regnum_p (gdbarch, regnum)) |
| 1598 | return i386_build_sse_type (); |
| 1599 | |
| 1600 | if (i386_mmx_regnum_p (gdbarch, regnum)) |
| 1601 | return i386_build_mmx_type (); |
| 1602 | |
| 1603 | return builtin_type_int; |
| 1604 | } |
| 1605 | |
| 1606 | /* Map a cooked register onto a raw register or memory. For the i386, |
| 1607 | the MMX registers need to be mapped onto floating point registers. */ |
| 1608 | |
| 1609 | static int |
| 1610 | i386_mmx_regnum_to_fp_regnum (struct regcache *regcache, int regnum) |
| 1611 | { |
| 1612 | struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache)); |
| 1613 | int mmxreg, fpreg; |
| 1614 | ULONGEST fstat; |
| 1615 | int tos; |
| 1616 | |
| 1617 | /* Define I387_ST0_REGNUM such that we use the proper definitions |
| 1618 | for REGCACHE's architecture. */ |
| 1619 | #define I387_ST0_REGNUM tdep->st0_regnum |
| 1620 | |
| 1621 | mmxreg = regnum - tdep->mm0_regnum; |
| 1622 | regcache_raw_read_unsigned (regcache, I387_FSTAT_REGNUM, &fstat); |
| 1623 | tos = (fstat >> 11) & 0x7; |
| 1624 | fpreg = (mmxreg + tos) % 8; |
| 1625 | |
| 1626 | return (I387_ST0_REGNUM + fpreg); |
| 1627 | |
| 1628 | #undef I387_ST0_REGNUM |
| 1629 | } |
| 1630 | |
| 1631 | static void |
| 1632 | i386_pseudo_register_read (struct gdbarch *gdbarch, struct regcache *regcache, |
| 1633 | int regnum, gdb_byte *buf) |
| 1634 | { |
| 1635 | if (i386_mmx_regnum_p (gdbarch, regnum)) |
| 1636 | { |
| 1637 | gdb_byte mmx_buf[MAX_REGISTER_SIZE]; |
| 1638 | int fpnum = i386_mmx_regnum_to_fp_regnum (regcache, regnum); |
| 1639 | |
| 1640 | /* Extract (always little endian). */ |
| 1641 | regcache_raw_read (regcache, fpnum, mmx_buf); |
| 1642 | memcpy (buf, mmx_buf, register_size (gdbarch, regnum)); |
| 1643 | } |
| 1644 | else |
| 1645 | regcache_raw_read (regcache, regnum, buf); |
| 1646 | } |
| 1647 | |
| 1648 | static void |
| 1649 | i386_pseudo_register_write (struct gdbarch *gdbarch, struct regcache *regcache, |
| 1650 | int regnum, const gdb_byte *buf) |
| 1651 | { |
| 1652 | if (i386_mmx_regnum_p (gdbarch, regnum)) |
| 1653 | { |
| 1654 | gdb_byte mmx_buf[MAX_REGISTER_SIZE]; |
| 1655 | int fpnum = i386_mmx_regnum_to_fp_regnum (regcache, regnum); |
| 1656 | |
| 1657 | /* Read ... */ |
| 1658 | regcache_raw_read (regcache, fpnum, mmx_buf); |
| 1659 | /* ... Modify ... (always little endian). */ |
| 1660 | memcpy (mmx_buf, buf, register_size (gdbarch, regnum)); |
| 1661 | /* ... Write. */ |
| 1662 | regcache_raw_write (regcache, fpnum, mmx_buf); |
| 1663 | } |
| 1664 | else |
| 1665 | regcache_raw_write (regcache, regnum, buf); |
| 1666 | } |
| 1667 | \f |
| 1668 | |
| 1669 | /* Return the register number of the register allocated by GCC after |
| 1670 | REGNUM, or -1 if there is no such register. */ |
| 1671 | |
| 1672 | static int |
| 1673 | i386_next_regnum (int regnum) |
| 1674 | { |
| 1675 | /* GCC allocates the registers in the order: |
| 1676 | |
| 1677 | %eax, %edx, %ecx, %ebx, %esi, %edi, %ebp, %esp, ... |
| 1678 | |
| 1679 | Since storing a variable in %esp doesn't make any sense we return |
| 1680 | -1 for %ebp and for %esp itself. */ |
| 1681 | static int next_regnum[] = |
| 1682 | { |
| 1683 | I386_EDX_REGNUM, /* Slot for %eax. */ |
| 1684 | I386_EBX_REGNUM, /* Slot for %ecx. */ |
| 1685 | I386_ECX_REGNUM, /* Slot for %edx. */ |
| 1686 | I386_ESI_REGNUM, /* Slot for %ebx. */ |
| 1687 | -1, -1, /* Slots for %esp and %ebp. */ |
| 1688 | I386_EDI_REGNUM, /* Slot for %esi. */ |
| 1689 | I386_EBP_REGNUM /* Slot for %edi. */ |
| 1690 | }; |
| 1691 | |
| 1692 | if (regnum >= 0 && regnum < sizeof (next_regnum) / sizeof (next_regnum[0])) |
| 1693 | return next_regnum[regnum]; |
| 1694 | |
| 1695 | return -1; |
| 1696 | } |
| 1697 | |
| 1698 | /* Return nonzero if a value of type TYPE stored in register REGNUM |
| 1699 | needs any special handling. */ |
| 1700 | |
| 1701 | static int |
| 1702 | i386_convert_register_p (int regnum, struct type *type) |
| 1703 | { |
| 1704 | int len = TYPE_LENGTH (type); |
| 1705 | |
| 1706 | /* Values may be spread across multiple registers. Most debugging |
| 1707 | formats aren't expressive enough to specify the locations, so |
| 1708 | some heuristics is involved. Right now we only handle types that |
| 1709 | have a length that is a multiple of the word size, since GCC |
| 1710 | doesn't seem to put any other types into registers. */ |
| 1711 | if (len > 4 && len % 4 == 0) |
| 1712 | { |
| 1713 | int last_regnum = regnum; |
| 1714 | |
| 1715 | while (len > 4) |
| 1716 | { |
| 1717 | last_regnum = i386_next_regnum (last_regnum); |
| 1718 | len -= 4; |
| 1719 | } |
| 1720 | |
| 1721 | if (last_regnum != -1) |
| 1722 | return 1; |
| 1723 | } |
| 1724 | |
| 1725 | return i386_fp_regnum_p (regnum); |
| 1726 | } |
| 1727 | |
| 1728 | /* Read a value of type TYPE from register REGNUM in frame FRAME, and |
| 1729 | return its contents in TO. */ |
| 1730 | |
| 1731 | static void |
| 1732 | i386_register_to_value (struct frame_info *frame, int regnum, |
| 1733 | struct type *type, gdb_byte *to) |
| 1734 | { |
| 1735 | int len = TYPE_LENGTH (type); |
| 1736 | |
| 1737 | /* FIXME: kettenis/20030609: What should we do if REGNUM isn't |
| 1738 | available in FRAME (i.e. if it wasn't saved)? */ |
| 1739 | |
| 1740 | if (i386_fp_regnum_p (regnum)) |
| 1741 | { |
| 1742 | i387_register_to_value (frame, regnum, type, to); |
| 1743 | return; |
| 1744 | } |
| 1745 | |
| 1746 | /* Read a value spread across multiple registers. */ |
| 1747 | |
| 1748 | gdb_assert (len > 4 && len % 4 == 0); |
| 1749 | |
| 1750 | while (len > 0) |
| 1751 | { |
| 1752 | gdb_assert (regnum != -1); |
| 1753 | gdb_assert (register_size (current_gdbarch, regnum) == 4); |
| 1754 | |
| 1755 | get_frame_register (frame, regnum, to); |
| 1756 | regnum = i386_next_regnum (regnum); |
| 1757 | len -= 4; |
| 1758 | to += 4; |
| 1759 | } |
| 1760 | } |
| 1761 | |
| 1762 | /* Write the contents FROM of a value of type TYPE into register |
| 1763 | REGNUM in frame FRAME. */ |
| 1764 | |
| 1765 | static void |
| 1766 | i386_value_to_register (struct frame_info *frame, int regnum, |
| 1767 | struct type *type, const gdb_byte *from) |
| 1768 | { |
| 1769 | int len = TYPE_LENGTH (type); |
| 1770 | |
| 1771 | if (i386_fp_regnum_p (regnum)) |
| 1772 | { |
| 1773 | i387_value_to_register (frame, regnum, type, from); |
| 1774 | return; |
| 1775 | } |
| 1776 | |
| 1777 | /* Write a value spread across multiple registers. */ |
| 1778 | |
| 1779 | gdb_assert (len > 4 && len % 4 == 0); |
| 1780 | |
| 1781 | while (len > 0) |
| 1782 | { |
| 1783 | gdb_assert (regnum != -1); |
| 1784 | gdb_assert (register_size (current_gdbarch, regnum) == 4); |
| 1785 | |
| 1786 | put_frame_register (frame, regnum, from); |
| 1787 | regnum = i386_next_regnum (regnum); |
| 1788 | len -= 4; |
| 1789 | from += 4; |
| 1790 | } |
| 1791 | } |
| 1792 | \f |
| 1793 | /* Supply register REGNUM from the buffer specified by GREGS and LEN |
| 1794 | in the general-purpose register set REGSET to register cache |
| 1795 | REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */ |
| 1796 | |
| 1797 | void |
| 1798 | i386_supply_gregset (const struct regset *regset, struct regcache *regcache, |
| 1799 | int regnum, const void *gregs, size_t len) |
| 1800 | { |
| 1801 | const struct gdbarch_tdep *tdep = gdbarch_tdep (regset->arch); |
| 1802 | const gdb_byte *regs = gregs; |
| 1803 | int i; |
| 1804 | |
| 1805 | gdb_assert (len == tdep->sizeof_gregset); |
| 1806 | |
| 1807 | for (i = 0; i < tdep->gregset_num_regs; i++) |
| 1808 | { |
| 1809 | if ((regnum == i || regnum == -1) |
| 1810 | && tdep->gregset_reg_offset[i] != -1) |
| 1811 | regcache_raw_supply (regcache, i, regs + tdep->gregset_reg_offset[i]); |
| 1812 | } |
| 1813 | } |
| 1814 | |
| 1815 | /* Collect register REGNUM from the register cache REGCACHE and store |
| 1816 | it in the buffer specified by GREGS and LEN as described by the |
| 1817 | general-purpose register set REGSET. If REGNUM is -1, do this for |
| 1818 | all registers in REGSET. */ |
| 1819 | |
| 1820 | void |
| 1821 | i386_collect_gregset (const struct regset *regset, |
| 1822 | const struct regcache *regcache, |
| 1823 | int regnum, void *gregs, size_t len) |
| 1824 | { |
| 1825 | const struct gdbarch_tdep *tdep = gdbarch_tdep (regset->arch); |
| 1826 | gdb_byte *regs = gregs; |
| 1827 | int i; |
| 1828 | |
| 1829 | gdb_assert (len == tdep->sizeof_gregset); |
| 1830 | |
| 1831 | for (i = 0; i < tdep->gregset_num_regs; i++) |
| 1832 | { |
| 1833 | if ((regnum == i || regnum == -1) |
| 1834 | && tdep->gregset_reg_offset[i] != -1) |
| 1835 | regcache_raw_collect (regcache, i, regs + tdep->gregset_reg_offset[i]); |
| 1836 | } |
| 1837 | } |
| 1838 | |
| 1839 | /* Supply register REGNUM from the buffer specified by FPREGS and LEN |
| 1840 | in the floating-point register set REGSET to register cache |
| 1841 | REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */ |
| 1842 | |
| 1843 | static void |
| 1844 | i386_supply_fpregset (const struct regset *regset, struct regcache *regcache, |
| 1845 | int regnum, const void *fpregs, size_t len) |
| 1846 | { |
| 1847 | const struct gdbarch_tdep *tdep = gdbarch_tdep (regset->arch); |
| 1848 | |
| 1849 | if (len == I387_SIZEOF_FXSAVE) |
| 1850 | { |
| 1851 | i387_supply_fxsave (regcache, regnum, fpregs); |
| 1852 | return; |
| 1853 | } |
| 1854 | |
| 1855 | gdb_assert (len == tdep->sizeof_fpregset); |
| 1856 | i387_supply_fsave (regcache, regnum, fpregs); |
| 1857 | } |
| 1858 | |
| 1859 | /* Collect register REGNUM from the register cache REGCACHE and store |
| 1860 | it in the buffer specified by FPREGS and LEN as described by the |
| 1861 | floating-point register set REGSET. If REGNUM is -1, do this for |
| 1862 | all registers in REGSET. */ |
| 1863 | |
| 1864 | static void |
| 1865 | i386_collect_fpregset (const struct regset *regset, |
| 1866 | const struct regcache *regcache, |
| 1867 | int regnum, void *fpregs, size_t len) |
| 1868 | { |
| 1869 | const struct gdbarch_tdep *tdep = gdbarch_tdep (regset->arch); |
| 1870 | |
| 1871 | if (len == I387_SIZEOF_FXSAVE) |
| 1872 | { |
| 1873 | i387_collect_fxsave (regcache, regnum, fpregs); |
| 1874 | return; |
| 1875 | } |
| 1876 | |
| 1877 | gdb_assert (len == tdep->sizeof_fpregset); |
| 1878 | i387_collect_fsave (regcache, regnum, fpregs); |
| 1879 | } |
| 1880 | |
| 1881 | /* Return the appropriate register set for the core section identified |
| 1882 | by SECT_NAME and SECT_SIZE. */ |
| 1883 | |
| 1884 | const struct regset * |
| 1885 | i386_regset_from_core_section (struct gdbarch *gdbarch, |
| 1886 | const char *sect_name, size_t sect_size) |
| 1887 | { |
| 1888 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 1889 | |
| 1890 | if (strcmp (sect_name, ".reg") == 0 && sect_size == tdep->sizeof_gregset) |
| 1891 | { |
| 1892 | if (tdep->gregset == NULL) |
| 1893 | tdep->gregset = regset_alloc (gdbarch, i386_supply_gregset, |
| 1894 | i386_collect_gregset); |
| 1895 | return tdep->gregset; |
| 1896 | } |
| 1897 | |
| 1898 | if ((strcmp (sect_name, ".reg2") == 0 && sect_size == tdep->sizeof_fpregset) |
| 1899 | || (strcmp (sect_name, ".reg-xfp") == 0 |
| 1900 | && sect_size == I387_SIZEOF_FXSAVE)) |
| 1901 | { |
| 1902 | if (tdep->fpregset == NULL) |
| 1903 | tdep->fpregset = regset_alloc (gdbarch, i386_supply_fpregset, |
| 1904 | i386_collect_fpregset); |
| 1905 | return tdep->fpregset; |
| 1906 | } |
| 1907 | |
| 1908 | return NULL; |
| 1909 | } |
| 1910 | \f |
| 1911 | |
| 1912 | #ifdef STATIC_TRANSFORM_NAME |
| 1913 | /* SunPRO encodes the static variables. This is not related to C++ |
| 1914 | mangling, it is done for C too. */ |
| 1915 | |
| 1916 | char * |
| 1917 | sunpro_static_transform_name (char *name) |
| 1918 | { |
| 1919 | char *p; |
| 1920 | if (IS_STATIC_TRANSFORM_NAME (name)) |
| 1921 | { |
| 1922 | /* For file-local statics there will be a period, a bunch of |
| 1923 | junk (the contents of which match a string given in the |
| 1924 | N_OPT), a period and the name. For function-local statics |
| 1925 | there will be a bunch of junk (which seems to change the |
| 1926 | second character from 'A' to 'B'), a period, the name of the |
| 1927 | function, and the name. So just skip everything before the |
| 1928 | last period. */ |
| 1929 | p = strrchr (name, '.'); |
| 1930 | if (p != NULL) |
| 1931 | name = p + 1; |
| 1932 | } |
| 1933 | return name; |
| 1934 | } |
| 1935 | #endif /* STATIC_TRANSFORM_NAME */ |
| 1936 | \f |
| 1937 | |
| 1938 | /* Stuff for WIN32 PE style DLL's but is pretty generic really. */ |
| 1939 | |
| 1940 | CORE_ADDR |
| 1941 | i386_pe_skip_trampoline_code (CORE_ADDR pc, char *name) |
| 1942 | { |
| 1943 | if (pc && read_memory_unsigned_integer (pc, 2) == 0x25ff) /* jmp *(dest) */ |
| 1944 | { |
| 1945 | unsigned long indirect = read_memory_unsigned_integer (pc + 2, 4); |
| 1946 | struct minimal_symbol *indsym = |
| 1947 | indirect ? lookup_minimal_symbol_by_pc (indirect) : 0; |
| 1948 | char *symname = indsym ? SYMBOL_LINKAGE_NAME (indsym) : 0; |
| 1949 | |
| 1950 | if (symname) |
| 1951 | { |
| 1952 | if (strncmp (symname, "__imp_", 6) == 0 |
| 1953 | || strncmp (symname, "_imp_", 5) == 0) |
| 1954 | return name ? 1 : read_memory_unsigned_integer (indirect, 4); |
| 1955 | } |
| 1956 | } |
| 1957 | return 0; /* Not a trampoline. */ |
| 1958 | } |
| 1959 | \f |
| 1960 | |
| 1961 | /* Return whether the frame preceding NEXT_FRAME corresponds to a |
| 1962 | sigtramp routine. */ |
| 1963 | |
| 1964 | static int |
| 1965 | i386_sigtramp_p (struct frame_info *next_frame) |
| 1966 | { |
| 1967 | CORE_ADDR pc = frame_pc_unwind (next_frame); |
| 1968 | char *name; |
| 1969 | |
| 1970 | find_pc_partial_function (pc, &name, NULL, NULL); |
| 1971 | return (name && strcmp ("_sigtramp", name) == 0); |
| 1972 | } |
| 1973 | \f |
| 1974 | |
| 1975 | /* We have two flavours of disassembly. The machinery on this page |
| 1976 | deals with switching between those. */ |
| 1977 | |
| 1978 | static int |
| 1979 | i386_print_insn (bfd_vma pc, struct disassemble_info *info) |
| 1980 | { |
| 1981 | gdb_assert (disassembly_flavor == att_flavor |
| 1982 | || disassembly_flavor == intel_flavor); |
| 1983 | |
| 1984 | /* FIXME: kettenis/20020915: Until disassembler_options is properly |
| 1985 | constified, cast to prevent a compiler warning. */ |
| 1986 | info->disassembler_options = (char *) disassembly_flavor; |
| 1987 | info->mach = gdbarch_bfd_arch_info (current_gdbarch)->mach; |
| 1988 | |
| 1989 | return print_insn_i386 (pc, info); |
| 1990 | } |
| 1991 | \f |
| 1992 | |
| 1993 | /* There are a few i386 architecture variants that differ only |
| 1994 | slightly from the generic i386 target. For now, we don't give them |
| 1995 | their own source file, but include them here. As a consequence, |
| 1996 | they'll always be included. */ |
| 1997 | |
| 1998 | /* System V Release 4 (SVR4). */ |
| 1999 | |
| 2000 | /* Return whether the frame preceding NEXT_FRAME corresponds to a SVR4 |
| 2001 | sigtramp routine. */ |
| 2002 | |
| 2003 | static int |
| 2004 | i386_svr4_sigtramp_p (struct frame_info *next_frame) |
| 2005 | { |
| 2006 | CORE_ADDR pc = frame_pc_unwind (next_frame); |
| 2007 | char *name; |
| 2008 | |
| 2009 | /* UnixWare uses _sigacthandler. The origin of the other symbols is |
| 2010 | currently unknown. */ |
| 2011 | find_pc_partial_function (pc, &name, NULL, NULL); |
| 2012 | return (name && (strcmp ("_sigreturn", name) == 0 |
| 2013 | || strcmp ("_sigacthandler", name) == 0 |
| 2014 | || strcmp ("sigvechandler", name) == 0)); |
| 2015 | } |
| 2016 | |
| 2017 | /* Assuming NEXT_FRAME is for a frame following a SVR4 sigtramp |
| 2018 | routine, return the address of the associated sigcontext (ucontext) |
| 2019 | structure. */ |
| 2020 | |
| 2021 | static CORE_ADDR |
| 2022 | i386_svr4_sigcontext_addr (struct frame_info *next_frame) |
| 2023 | { |
| 2024 | gdb_byte buf[4]; |
| 2025 | CORE_ADDR sp; |
| 2026 | |
| 2027 | frame_unwind_register (next_frame, I386_ESP_REGNUM, buf); |
| 2028 | sp = extract_unsigned_integer (buf, 4); |
| 2029 | |
| 2030 | return read_memory_unsigned_integer (sp + 8, 4); |
| 2031 | } |
| 2032 | \f |
| 2033 | |
| 2034 | /* Generic ELF. */ |
| 2035 | |
| 2036 | void |
| 2037 | i386_elf_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 2038 | { |
| 2039 | /* We typically use stabs-in-ELF with the SVR4 register numbering. */ |
| 2040 | set_gdbarch_stab_reg_to_regnum (gdbarch, i386_svr4_reg_to_regnum); |
| 2041 | } |
| 2042 | |
| 2043 | /* System V Release 4 (SVR4). */ |
| 2044 | |
| 2045 | void |
| 2046 | i386_svr4_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 2047 | { |
| 2048 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 2049 | |
| 2050 | /* System V Release 4 uses ELF. */ |
| 2051 | i386_elf_init_abi (info, gdbarch); |
| 2052 | |
| 2053 | /* System V Release 4 has shared libraries. */ |
| 2054 | set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target); |
| 2055 | |
| 2056 | tdep->sigtramp_p = i386_svr4_sigtramp_p; |
| 2057 | tdep->sigcontext_addr = i386_svr4_sigcontext_addr; |
| 2058 | tdep->sc_pc_offset = 36 + 14 * 4; |
| 2059 | tdep->sc_sp_offset = 36 + 17 * 4; |
| 2060 | |
| 2061 | tdep->jb_pc_offset = 20; |
| 2062 | } |
| 2063 | |
| 2064 | /* DJGPP. */ |
| 2065 | |
| 2066 | static void |
| 2067 | i386_go32_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 2068 | { |
| 2069 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 2070 | |
| 2071 | /* DJGPP doesn't have any special frames for signal handlers. */ |
| 2072 | tdep->sigtramp_p = NULL; |
| 2073 | |
| 2074 | tdep->jb_pc_offset = 36; |
| 2075 | } |
| 2076 | |
| 2077 | /* NetWare. */ |
| 2078 | |
| 2079 | static void |
| 2080 | i386_nw_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 2081 | { |
| 2082 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 2083 | |
| 2084 | tdep->jb_pc_offset = 24; |
| 2085 | } |
| 2086 | \f |
| 2087 | |
| 2088 | /* i386 register groups. In addition to the normal groups, add "mmx" |
| 2089 | and "sse". */ |
| 2090 | |
| 2091 | static struct reggroup *i386_sse_reggroup; |
| 2092 | static struct reggroup *i386_mmx_reggroup; |
| 2093 | |
| 2094 | static void |
| 2095 | i386_init_reggroups (void) |
| 2096 | { |
| 2097 | i386_sse_reggroup = reggroup_new ("sse", USER_REGGROUP); |
| 2098 | i386_mmx_reggroup = reggroup_new ("mmx", USER_REGGROUP); |
| 2099 | } |
| 2100 | |
| 2101 | static void |
| 2102 | i386_add_reggroups (struct gdbarch *gdbarch) |
| 2103 | { |
| 2104 | reggroup_add (gdbarch, i386_sse_reggroup); |
| 2105 | reggroup_add (gdbarch, i386_mmx_reggroup); |
| 2106 | reggroup_add (gdbarch, general_reggroup); |
| 2107 | reggroup_add (gdbarch, float_reggroup); |
| 2108 | reggroup_add (gdbarch, all_reggroup); |
| 2109 | reggroup_add (gdbarch, save_reggroup); |
| 2110 | reggroup_add (gdbarch, restore_reggroup); |
| 2111 | reggroup_add (gdbarch, vector_reggroup); |
| 2112 | reggroup_add (gdbarch, system_reggroup); |
| 2113 | } |
| 2114 | |
| 2115 | int |
| 2116 | i386_register_reggroup_p (struct gdbarch *gdbarch, int regnum, |
| 2117 | struct reggroup *group) |
| 2118 | { |
| 2119 | int sse_regnum_p = (i386_sse_regnum_p (gdbarch, regnum) |
| 2120 | || i386_mxcsr_regnum_p (gdbarch, regnum)); |
| 2121 | int fp_regnum_p = (i386_fp_regnum_p (regnum) |
| 2122 | || i386_fpc_regnum_p (regnum)); |
| 2123 | int mmx_regnum_p = (i386_mmx_regnum_p (gdbarch, regnum)); |
| 2124 | |
| 2125 | if (group == i386_mmx_reggroup) |
| 2126 | return mmx_regnum_p; |
| 2127 | if (group == i386_sse_reggroup) |
| 2128 | return sse_regnum_p; |
| 2129 | if (group == vector_reggroup) |
| 2130 | return (mmx_regnum_p || sse_regnum_p); |
| 2131 | if (group == float_reggroup) |
| 2132 | return fp_regnum_p; |
| 2133 | if (group == general_reggroup) |
| 2134 | return (!fp_regnum_p && !mmx_regnum_p && !sse_regnum_p); |
| 2135 | |
| 2136 | return default_register_reggroup_p (gdbarch, regnum, group); |
| 2137 | } |
| 2138 | \f |
| 2139 | |
| 2140 | /* Get the ARGIth function argument for the current function. */ |
| 2141 | |
| 2142 | static CORE_ADDR |
| 2143 | i386_fetch_pointer_argument (struct frame_info *frame, int argi, |
| 2144 | struct type *type) |
| 2145 | { |
| 2146 | CORE_ADDR sp = get_frame_register_unsigned (frame, I386_ESP_REGNUM); |
| 2147 | return read_memory_unsigned_integer (sp + (4 * (argi + 1)), 4); |
| 2148 | } |
| 2149 | |
| 2150 | \f |
| 2151 | static struct gdbarch * |
| 2152 | i386_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) |
| 2153 | { |
| 2154 | struct gdbarch_tdep *tdep; |
| 2155 | struct gdbarch *gdbarch; |
| 2156 | |
| 2157 | /* If there is already a candidate, use it. */ |
| 2158 | arches = gdbarch_list_lookup_by_info (arches, &info); |
| 2159 | if (arches != NULL) |
| 2160 | return arches->gdbarch; |
| 2161 | |
| 2162 | /* Allocate space for the new architecture. */ |
| 2163 | tdep = XMALLOC (struct gdbarch_tdep); |
| 2164 | gdbarch = gdbarch_alloc (&info, tdep); |
| 2165 | |
| 2166 | /* General-purpose registers. */ |
| 2167 | tdep->gregset = NULL; |
| 2168 | tdep->gregset_reg_offset = NULL; |
| 2169 | tdep->gregset_num_regs = I386_NUM_GREGS; |
| 2170 | tdep->sizeof_gregset = 0; |
| 2171 | |
| 2172 | /* Floating-point registers. */ |
| 2173 | tdep->fpregset = NULL; |
| 2174 | tdep->sizeof_fpregset = I387_SIZEOF_FSAVE; |
| 2175 | |
| 2176 | /* The default settings include the FPU registers, the MMX registers |
| 2177 | and the SSE registers. This can be overridden for a specific ABI |
| 2178 | by adjusting the members `st0_regnum', `mm0_regnum' and |
| 2179 | `num_xmm_regs' of `struct gdbarch_tdep', otherwise the registers |
| 2180 | will show up in the output of "info all-registers". Ideally we |
| 2181 | should try to autodetect whether they are available, such that we |
| 2182 | can prevent "info all-registers" from displaying registers that |
| 2183 | aren't available. |
| 2184 | |
| 2185 | NOTE: kevinb/2003-07-13: ... if it's a choice between printing |
| 2186 | [the SSE registers] always (even when they don't exist) or never |
| 2187 | showing them to the user (even when they do exist), I prefer the |
| 2188 | former over the latter. */ |
| 2189 | |
| 2190 | tdep->st0_regnum = I386_ST0_REGNUM; |
| 2191 | |
| 2192 | /* The MMX registers are implemented as pseudo-registers. Put off |
| 2193 | calculating the register number for %mm0 until we know the number |
| 2194 | of raw registers. */ |
| 2195 | tdep->mm0_regnum = 0; |
| 2196 | |
| 2197 | /* I386_NUM_XREGS includes %mxcsr, so substract one. */ |
| 2198 | tdep->num_xmm_regs = I386_NUM_XREGS - 1; |
| 2199 | |
| 2200 | tdep->jb_pc_offset = -1; |
| 2201 | tdep->struct_return = pcc_struct_return; |
| 2202 | tdep->sigtramp_start = 0; |
| 2203 | tdep->sigtramp_end = 0; |
| 2204 | tdep->sigtramp_p = i386_sigtramp_p; |
| 2205 | tdep->sigcontext_addr = NULL; |
| 2206 | tdep->sc_reg_offset = NULL; |
| 2207 | tdep->sc_pc_offset = -1; |
| 2208 | tdep->sc_sp_offset = -1; |
| 2209 | |
| 2210 | /* The format used for `long double' on almost all i386 targets is |
| 2211 | the i387 extended floating-point format. In fact, of all targets |
| 2212 | in the GCC 2.95 tree, only OSF/1 does it different, and insists |
| 2213 | on having a `long double' that's not `long' at all. */ |
| 2214 | set_gdbarch_long_double_format (gdbarch, &floatformat_i387_ext); |
| 2215 | |
| 2216 | /* Although the i387 extended floating-point has only 80 significant |
| 2217 | bits, a `long double' actually takes up 96, probably to enforce |
| 2218 | alignment. */ |
| 2219 | set_gdbarch_long_double_bit (gdbarch, 96); |
| 2220 | |
| 2221 | /* The default ABI includes general-purpose registers, |
| 2222 | floating-point registers, and the SSE registers. */ |
| 2223 | set_gdbarch_num_regs (gdbarch, I386_SSE_NUM_REGS); |
| 2224 | set_gdbarch_register_name (gdbarch, i386_register_name); |
| 2225 | set_gdbarch_register_type (gdbarch, i386_register_type); |
| 2226 | |
| 2227 | /* Register numbers of various important registers. */ |
| 2228 | set_gdbarch_sp_regnum (gdbarch, I386_ESP_REGNUM); /* %esp */ |
| 2229 | set_gdbarch_pc_regnum (gdbarch, I386_EIP_REGNUM); /* %eip */ |
| 2230 | set_gdbarch_ps_regnum (gdbarch, I386_EFLAGS_REGNUM); /* %eflags */ |
| 2231 | set_gdbarch_fp0_regnum (gdbarch, I386_ST0_REGNUM); /* %st(0) */ |
| 2232 | |
| 2233 | /* NOTE: kettenis/20040418: GCC does have two possible register |
| 2234 | numbering schemes on the i386: dbx and SVR4. These schemes |
| 2235 | differ in how they number %ebp, %esp, %eflags, and the |
| 2236 | floating-point registers, and are implemented by the arrays |
| 2237 | dbx_register_map[] and svr4_dbx_register_map in |
| 2238 | gcc/config/i386.c. GCC also defines a third numbering scheme in |
| 2239 | gcc/config/i386.c, which it designates as the "default" register |
| 2240 | map used in 64bit mode. This last register numbering scheme is |
| 2241 | implemented in dbx64_register_map, and is used for AMD64; see |
| 2242 | amd64-tdep.c. |
| 2243 | |
| 2244 | Currently, each GCC i386 target always uses the same register |
| 2245 | numbering scheme across all its supported debugging formats |
| 2246 | i.e. SDB (COFF), stabs and DWARF 2. This is because |
| 2247 | gcc/sdbout.c, gcc/dbxout.c and gcc/dwarf2out.c all use the |
| 2248 | DBX_REGISTER_NUMBER macro which is defined by each target's |
| 2249 | respective config header in a manner independent of the requested |
| 2250 | output debugging format. |
| 2251 | |
| 2252 | This does not match the arrangement below, which presumes that |
| 2253 | the SDB and stabs numbering schemes differ from the DWARF and |
| 2254 | DWARF 2 ones. The reason for this arrangement is that it is |
| 2255 | likely to get the numbering scheme for the target's |
| 2256 | default/native debug format right. For targets where GCC is the |
| 2257 | native compiler (FreeBSD, NetBSD, OpenBSD, GNU/Linux) or for |
| 2258 | targets where the native toolchain uses a different numbering |
| 2259 | scheme for a particular debug format (stabs-in-ELF on Solaris) |
| 2260 | the defaults below will have to be overridden, like |
| 2261 | i386_elf_init_abi() does. */ |
| 2262 | |
| 2263 | /* Use the dbx register numbering scheme for stabs and COFF. */ |
| 2264 | set_gdbarch_stab_reg_to_regnum (gdbarch, i386_dbx_reg_to_regnum); |
| 2265 | set_gdbarch_sdb_reg_to_regnum (gdbarch, i386_dbx_reg_to_regnum); |
| 2266 | |
| 2267 | /* Use the SVR4 register numbering scheme for DWARF and DWARF 2. */ |
| 2268 | set_gdbarch_dwarf_reg_to_regnum (gdbarch, i386_svr4_reg_to_regnum); |
| 2269 | set_gdbarch_dwarf2_reg_to_regnum (gdbarch, i386_svr4_reg_to_regnum); |
| 2270 | |
| 2271 | /* We don't define ECOFF_REG_TO_REGNUM, since ECOFF doesn't seem to |
| 2272 | be in use on any of the supported i386 targets. */ |
| 2273 | |
| 2274 | set_gdbarch_print_float_info (gdbarch, i387_print_float_info); |
| 2275 | |
| 2276 | set_gdbarch_get_longjmp_target (gdbarch, i386_get_longjmp_target); |
| 2277 | |
| 2278 | /* Call dummy code. */ |
| 2279 | set_gdbarch_push_dummy_call (gdbarch, i386_push_dummy_call); |
| 2280 | |
| 2281 | set_gdbarch_convert_register_p (gdbarch, i386_convert_register_p); |
| 2282 | set_gdbarch_register_to_value (gdbarch, i386_register_to_value); |
| 2283 | set_gdbarch_value_to_register (gdbarch, i386_value_to_register); |
| 2284 | |
| 2285 | set_gdbarch_return_value (gdbarch, i386_return_value); |
| 2286 | |
| 2287 | set_gdbarch_skip_prologue (gdbarch, i386_skip_prologue); |
| 2288 | |
| 2289 | /* Stack grows downward. */ |
| 2290 | set_gdbarch_inner_than (gdbarch, core_addr_lessthan); |
| 2291 | |
| 2292 | set_gdbarch_breakpoint_from_pc (gdbarch, i386_breakpoint_from_pc); |
| 2293 | set_gdbarch_decr_pc_after_break (gdbarch, 1); |
| 2294 | |
| 2295 | set_gdbarch_frame_args_skip (gdbarch, 8); |
| 2296 | |
| 2297 | /* Wire in the MMX registers. */ |
| 2298 | set_gdbarch_num_pseudo_regs (gdbarch, i386_num_mmx_regs); |
| 2299 | set_gdbarch_pseudo_register_read (gdbarch, i386_pseudo_register_read); |
| 2300 | set_gdbarch_pseudo_register_write (gdbarch, i386_pseudo_register_write); |
| 2301 | |
| 2302 | set_gdbarch_print_insn (gdbarch, i386_print_insn); |
| 2303 | |
| 2304 | set_gdbarch_unwind_dummy_id (gdbarch, i386_unwind_dummy_id); |
| 2305 | |
| 2306 | set_gdbarch_unwind_pc (gdbarch, i386_unwind_pc); |
| 2307 | |
| 2308 | /* Add the i386 register groups. */ |
| 2309 | i386_add_reggroups (gdbarch); |
| 2310 | set_gdbarch_register_reggroup_p (gdbarch, i386_register_reggroup_p); |
| 2311 | |
| 2312 | /* Helper for function argument information. */ |
| 2313 | set_gdbarch_fetch_pointer_argument (gdbarch, i386_fetch_pointer_argument); |
| 2314 | |
| 2315 | /* Hook in the DWARF CFI frame unwinder. */ |
| 2316 | frame_unwind_append_sniffer (gdbarch, dwarf2_frame_sniffer); |
| 2317 | |
| 2318 | frame_base_set_default (gdbarch, &i386_frame_base); |
| 2319 | |
| 2320 | /* Hook in ABI-specific overrides, if they have been registered. */ |
| 2321 | gdbarch_init_osabi (info, gdbarch); |
| 2322 | |
| 2323 | frame_unwind_append_sniffer (gdbarch, i386_sigtramp_frame_sniffer); |
| 2324 | frame_unwind_append_sniffer (gdbarch, i386_frame_sniffer); |
| 2325 | |
| 2326 | /* If we have a register mapping, enable the generic core file |
| 2327 | support, unless it has already been enabled. */ |
| 2328 | if (tdep->gregset_reg_offset |
| 2329 | && !gdbarch_regset_from_core_section_p (gdbarch)) |
| 2330 | set_gdbarch_regset_from_core_section (gdbarch, |
| 2331 | i386_regset_from_core_section); |
| 2332 | |
| 2333 | /* Unless support for MMX has been disabled, make %mm0 the first |
| 2334 | pseudo-register. */ |
| 2335 | if (tdep->mm0_regnum == 0) |
| 2336 | tdep->mm0_regnum = gdbarch_num_regs (gdbarch); |
| 2337 | |
| 2338 | return gdbarch; |
| 2339 | } |
| 2340 | |
| 2341 | static enum gdb_osabi |
| 2342 | i386_coff_osabi_sniffer (bfd *abfd) |
| 2343 | { |
| 2344 | if (strcmp (bfd_get_target (abfd), "coff-go32-exe") == 0 |
| 2345 | || strcmp (bfd_get_target (abfd), "coff-go32") == 0) |
| 2346 | return GDB_OSABI_GO32; |
| 2347 | |
| 2348 | return GDB_OSABI_UNKNOWN; |
| 2349 | } |
| 2350 | |
| 2351 | static enum gdb_osabi |
| 2352 | i386_nlm_osabi_sniffer (bfd *abfd) |
| 2353 | { |
| 2354 | return GDB_OSABI_NETWARE; |
| 2355 | } |
| 2356 | \f |
| 2357 | |
| 2358 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
| 2359 | void _initialize_i386_tdep (void); |
| 2360 | |
| 2361 | void |
| 2362 | _initialize_i386_tdep (void) |
| 2363 | { |
| 2364 | register_gdbarch_init (bfd_arch_i386, i386_gdbarch_init); |
| 2365 | |
| 2366 | /* Add the variable that controls the disassembly flavor. */ |
| 2367 | add_setshow_enum_cmd ("disassembly-flavor", no_class, valid_flavors, |
| 2368 | &disassembly_flavor, _("\ |
| 2369 | Set the disassembly flavor."), _("\ |
| 2370 | Show the disassembly flavor."), _("\ |
| 2371 | The valid values are \"att\" and \"intel\", and the default value is \"att\"."), |
| 2372 | NULL, |
| 2373 | NULL, /* FIXME: i18n: */ |
| 2374 | &setlist, &showlist); |
| 2375 | |
| 2376 | /* Add the variable that controls the convention for returning |
| 2377 | structs. */ |
| 2378 | add_setshow_enum_cmd ("struct-convention", no_class, valid_conventions, |
| 2379 | &struct_convention, _("\ |
| 2380 | Set the convention for returning small structs."), _("\ |
| 2381 | Show the convention for returning small structs."), _("\ |
| 2382 | Valid values are \"default\", \"pcc\" and \"reg\", and the default value\n\ |
| 2383 | is \"default\"."), |
| 2384 | NULL, |
| 2385 | NULL, /* FIXME: i18n: */ |
| 2386 | &setlist, &showlist); |
| 2387 | |
| 2388 | gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_coff_flavour, |
| 2389 | i386_coff_osabi_sniffer); |
| 2390 | gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_nlm_flavour, |
| 2391 | i386_nlm_osabi_sniffer); |
| 2392 | |
| 2393 | gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_SVR4, |
| 2394 | i386_svr4_init_abi); |
| 2395 | gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_GO32, |
| 2396 | i386_go32_init_abi); |
| 2397 | gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_NETWARE, |
| 2398 | i386_nw_init_abi); |
| 2399 | |
| 2400 | /* Initialize the i386 specific register groups. */ |
| 2401 | i386_init_reggroups (); |
| 2402 | } |