| 1 | /* Copyright (C) 2009-2018 Free Software Foundation, Inc. |
| 2 | |
| 3 | This file is part of GDB. |
| 4 | |
| 5 | This program is free software; you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by |
| 7 | the Free Software Foundation; either version 3 of the License, or |
| 8 | (at your option) any later version. |
| 9 | |
| 10 | This program is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | GNU General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU General Public License |
| 16 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 17 | |
| 18 | #include "defs.h" |
| 19 | #include "osabi.h" |
| 20 | #include "amd64-tdep.h" |
| 21 | #include "x86-xstate.h" |
| 22 | #include "gdbtypes.h" |
| 23 | #include "gdbcore.h" |
| 24 | #include "regcache.h" |
| 25 | #include "windows-tdep.h" |
| 26 | #include "frame.h" |
| 27 | #include "objfiles.h" |
| 28 | #include "frame-unwind.h" |
| 29 | #include "coff/internal.h" |
| 30 | #include "coff/i386.h" |
| 31 | #include "coff/pe.h" |
| 32 | #include "libcoff.h" |
| 33 | #include "value.h" |
| 34 | #include <algorithm> |
| 35 | |
| 36 | /* The registers used to pass integer arguments during a function call. */ |
| 37 | static int amd64_windows_dummy_call_integer_regs[] = |
| 38 | { |
| 39 | AMD64_RCX_REGNUM, /* %rcx */ |
| 40 | AMD64_RDX_REGNUM, /* %rdx */ |
| 41 | AMD64_R8_REGNUM, /* %r8 */ |
| 42 | AMD64_R9_REGNUM /* %r9 */ |
| 43 | }; |
| 44 | |
| 45 | /* Return nonzero if an argument of type TYPE should be passed |
| 46 | via one of the integer registers. */ |
| 47 | |
| 48 | static int |
| 49 | amd64_windows_passed_by_integer_register (struct type *type) |
| 50 | { |
| 51 | switch (TYPE_CODE (type)) |
| 52 | { |
| 53 | case TYPE_CODE_INT: |
| 54 | case TYPE_CODE_ENUM: |
| 55 | case TYPE_CODE_BOOL: |
| 56 | case TYPE_CODE_RANGE: |
| 57 | case TYPE_CODE_CHAR: |
| 58 | case TYPE_CODE_PTR: |
| 59 | case TYPE_CODE_REF: |
| 60 | case TYPE_CODE_RVALUE_REF: |
| 61 | case TYPE_CODE_STRUCT: |
| 62 | case TYPE_CODE_UNION: |
| 63 | return (TYPE_LENGTH (type) == 1 |
| 64 | || TYPE_LENGTH (type) == 2 |
| 65 | || TYPE_LENGTH (type) == 4 |
| 66 | || TYPE_LENGTH (type) == 8); |
| 67 | |
| 68 | default: |
| 69 | return 0; |
| 70 | } |
| 71 | } |
| 72 | |
| 73 | /* Return nonzero if an argument of type TYPE should be passed |
| 74 | via one of the XMM registers. */ |
| 75 | |
| 76 | static int |
| 77 | amd64_windows_passed_by_xmm_register (struct type *type) |
| 78 | { |
| 79 | return ((TYPE_CODE (type) == TYPE_CODE_FLT |
| 80 | || TYPE_CODE (type) == TYPE_CODE_DECFLOAT) |
| 81 | && (TYPE_LENGTH (type) == 4 || TYPE_LENGTH (type) == 8)); |
| 82 | } |
| 83 | |
| 84 | /* Return non-zero iff an argument of the given TYPE should be passed |
| 85 | by pointer. */ |
| 86 | |
| 87 | static int |
| 88 | amd64_windows_passed_by_pointer (struct type *type) |
| 89 | { |
| 90 | if (amd64_windows_passed_by_integer_register (type)) |
| 91 | return 0; |
| 92 | |
| 93 | if (amd64_windows_passed_by_xmm_register (type)) |
| 94 | return 0; |
| 95 | |
| 96 | return 1; |
| 97 | } |
| 98 | |
| 99 | /* For each argument that should be passed by pointer, reserve some |
| 100 | stack space, store a copy of the argument on the stack, and replace |
| 101 | the argument by its address. Return the new Stack Pointer value. |
| 102 | |
| 103 | NARGS is the number of arguments. ARGS is the array containing |
| 104 | the value of each argument. SP is value of the Stack Pointer. */ |
| 105 | |
| 106 | static CORE_ADDR |
| 107 | amd64_windows_adjust_args_passed_by_pointer (struct value **args, |
| 108 | int nargs, CORE_ADDR sp) |
| 109 | { |
| 110 | int i; |
| 111 | |
| 112 | for (i = 0; i < nargs; i++) |
| 113 | if (amd64_windows_passed_by_pointer (value_type (args[i]))) |
| 114 | { |
| 115 | struct type *type = value_type (args[i]); |
| 116 | const gdb_byte *valbuf = value_contents (args[i]); |
| 117 | const int len = TYPE_LENGTH (type); |
| 118 | |
| 119 | /* Store a copy of that argument on the stack, aligned to |
| 120 | a 16 bytes boundary, and then use the copy's address as |
| 121 | the argument. */ |
| 122 | |
| 123 | sp -= len; |
| 124 | sp &= ~0xf; |
| 125 | write_memory (sp, valbuf, len); |
| 126 | |
| 127 | args[i] |
| 128 | = value_addr (value_from_contents_and_address (type, valbuf, sp)); |
| 129 | } |
| 130 | |
| 131 | return sp; |
| 132 | } |
| 133 | |
| 134 | /* Store the value of ARG in register REGNO (right-justified). |
| 135 | REGCACHE is the register cache. */ |
| 136 | |
| 137 | static void |
| 138 | amd64_windows_store_arg_in_reg (struct regcache *regcache, |
| 139 | struct value *arg, int regno) |
| 140 | { |
| 141 | struct type *type = value_type (arg); |
| 142 | const gdb_byte *valbuf = value_contents (arg); |
| 143 | gdb_byte buf[8]; |
| 144 | |
| 145 | gdb_assert (TYPE_LENGTH (type) <= 8); |
| 146 | memset (buf, 0, sizeof buf); |
| 147 | memcpy (buf, valbuf, std::min (TYPE_LENGTH (type), (unsigned int) 8)); |
| 148 | regcache->cooked_write (regno, buf); |
| 149 | } |
| 150 | |
| 151 | /* Push the arguments for an inferior function call, and return |
| 152 | the updated value of the SP (Stack Pointer). |
| 153 | |
| 154 | All arguments are identical to the arguments used in |
| 155 | amd64_windows_push_dummy_call. */ |
| 156 | |
| 157 | static CORE_ADDR |
| 158 | amd64_windows_push_arguments (struct regcache *regcache, int nargs, |
| 159 | struct value **args, CORE_ADDR sp, |
| 160 | int struct_return) |
| 161 | { |
| 162 | int reg_idx = 0; |
| 163 | int i; |
| 164 | struct value **stack_args = XALLOCAVEC (struct value *, nargs); |
| 165 | int num_stack_args = 0; |
| 166 | int num_elements = 0; |
| 167 | int element = 0; |
| 168 | |
| 169 | /* First, handle the arguments passed by pointer. |
| 170 | |
| 171 | These arguments are replaced by pointers to a copy we are making |
| 172 | in inferior memory. So use a copy of the ARGS table, to avoid |
| 173 | modifying the original one. */ |
| 174 | { |
| 175 | struct value **args1 = XALLOCAVEC (struct value *, nargs); |
| 176 | |
| 177 | memcpy (args1, args, nargs * sizeof (struct value *)); |
| 178 | sp = amd64_windows_adjust_args_passed_by_pointer (args1, nargs, sp); |
| 179 | args = args1; |
| 180 | } |
| 181 | |
| 182 | /* Reserve a register for the "hidden" argument. */ |
| 183 | if (struct_return) |
| 184 | reg_idx++; |
| 185 | |
| 186 | for (i = 0; i < nargs; i++) |
| 187 | { |
| 188 | struct type *type = value_type (args[i]); |
| 189 | int len = TYPE_LENGTH (type); |
| 190 | int on_stack_p = 1; |
| 191 | |
| 192 | if (reg_idx < ARRAY_SIZE (amd64_windows_dummy_call_integer_regs)) |
| 193 | { |
| 194 | if (amd64_windows_passed_by_integer_register (type)) |
| 195 | { |
| 196 | amd64_windows_store_arg_in_reg |
| 197 | (regcache, args[i], |
| 198 | amd64_windows_dummy_call_integer_regs[reg_idx]); |
| 199 | on_stack_p = 0; |
| 200 | reg_idx++; |
| 201 | } |
| 202 | else if (amd64_windows_passed_by_xmm_register (type)) |
| 203 | { |
| 204 | amd64_windows_store_arg_in_reg |
| 205 | (regcache, args[i], AMD64_XMM0_REGNUM + reg_idx); |
| 206 | /* In case of varargs, these parameters must also be |
| 207 | passed via the integer registers. */ |
| 208 | amd64_windows_store_arg_in_reg |
| 209 | (regcache, args[i], |
| 210 | amd64_windows_dummy_call_integer_regs[reg_idx]); |
| 211 | on_stack_p = 0; |
| 212 | reg_idx++; |
| 213 | } |
| 214 | } |
| 215 | |
| 216 | if (on_stack_p) |
| 217 | { |
| 218 | num_elements += ((len + 7) / 8); |
| 219 | stack_args[num_stack_args++] = args[i]; |
| 220 | } |
| 221 | } |
| 222 | |
| 223 | /* Allocate space for the arguments on the stack, keeping it |
| 224 | aligned on a 16 byte boundary. */ |
| 225 | sp -= num_elements * 8; |
| 226 | sp &= ~0xf; |
| 227 | |
| 228 | /* Write out the arguments to the stack. */ |
| 229 | for (i = 0; i < num_stack_args; i++) |
| 230 | { |
| 231 | struct type *type = value_type (stack_args[i]); |
| 232 | const gdb_byte *valbuf = value_contents (stack_args[i]); |
| 233 | |
| 234 | write_memory (sp + element * 8, valbuf, TYPE_LENGTH (type)); |
| 235 | element += ((TYPE_LENGTH (type) + 7) / 8); |
| 236 | } |
| 237 | |
| 238 | return sp; |
| 239 | } |
| 240 | |
| 241 | /* Implement the "push_dummy_call" gdbarch method. */ |
| 242 | |
| 243 | static CORE_ADDR |
| 244 | amd64_windows_push_dummy_call |
| 245 | (struct gdbarch *gdbarch, struct value *function, |
| 246 | struct regcache *regcache, CORE_ADDR bp_addr, |
| 247 | int nargs, struct value **args, |
| 248 | CORE_ADDR sp, int struct_return, CORE_ADDR struct_addr) |
| 249 | { |
| 250 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 251 | gdb_byte buf[8]; |
| 252 | |
| 253 | /* Pass arguments. */ |
| 254 | sp = amd64_windows_push_arguments (regcache, nargs, args, sp, |
| 255 | struct_return); |
| 256 | |
| 257 | /* Pass "hidden" argument". */ |
| 258 | if (struct_return) |
| 259 | { |
| 260 | /* The "hidden" argument is passed throught the first argument |
| 261 | register. */ |
| 262 | const int arg_regnum = amd64_windows_dummy_call_integer_regs[0]; |
| 263 | |
| 264 | store_unsigned_integer (buf, 8, byte_order, struct_addr); |
| 265 | regcache->cooked_write (arg_regnum, buf); |
| 266 | } |
| 267 | |
| 268 | /* Reserve some memory on the stack for the integer-parameter |
| 269 | registers, as required by the ABI. */ |
| 270 | sp -= ARRAY_SIZE (amd64_windows_dummy_call_integer_regs) * 8; |
| 271 | |
| 272 | /* Store return address. */ |
| 273 | sp -= 8; |
| 274 | store_unsigned_integer (buf, 8, byte_order, bp_addr); |
| 275 | write_memory (sp, buf, 8); |
| 276 | |
| 277 | /* Update the stack pointer... */ |
| 278 | store_unsigned_integer (buf, 8, byte_order, sp); |
| 279 | regcache->cooked_write (AMD64_RSP_REGNUM, buf); |
| 280 | |
| 281 | /* ...and fake a frame pointer. */ |
| 282 | regcache->cooked_write (AMD64_RBP_REGNUM, buf); |
| 283 | |
| 284 | return sp + 16; |
| 285 | } |
| 286 | |
| 287 | /* Implement the "return_value" gdbarch method for amd64-windows. */ |
| 288 | |
| 289 | static enum return_value_convention |
| 290 | amd64_windows_return_value (struct gdbarch *gdbarch, struct value *function, |
| 291 | struct type *type, struct regcache *regcache, |
| 292 | gdb_byte *readbuf, const gdb_byte *writebuf) |
| 293 | { |
| 294 | int len = TYPE_LENGTH (type); |
| 295 | int regnum = -1; |
| 296 | |
| 297 | /* See if our value is returned through a register. If it is, then |
| 298 | store the associated register number in REGNUM. */ |
| 299 | switch (TYPE_CODE (type)) |
| 300 | { |
| 301 | case TYPE_CODE_FLT: |
| 302 | case TYPE_CODE_DECFLOAT: |
| 303 | /* __m128, __m128i, __m128d, floats, and doubles are returned |
| 304 | via XMM0. */ |
| 305 | if (len == 4 || len == 8 || len == 16) |
| 306 | regnum = AMD64_XMM0_REGNUM; |
| 307 | break; |
| 308 | default: |
| 309 | /* All other values that are 1, 2, 4 or 8 bytes long are returned |
| 310 | via RAX. */ |
| 311 | if (len == 1 || len == 2 || len == 4 || len == 8) |
| 312 | regnum = AMD64_RAX_REGNUM; |
| 313 | break; |
| 314 | } |
| 315 | |
| 316 | if (regnum < 0) |
| 317 | { |
| 318 | /* RAX contains the address where the return value has been stored. */ |
| 319 | if (readbuf) |
| 320 | { |
| 321 | ULONGEST addr; |
| 322 | |
| 323 | regcache_raw_read_unsigned (regcache, AMD64_RAX_REGNUM, &addr); |
| 324 | read_memory (addr, readbuf, TYPE_LENGTH (type)); |
| 325 | } |
| 326 | return RETURN_VALUE_ABI_RETURNS_ADDRESS; |
| 327 | } |
| 328 | else |
| 329 | { |
| 330 | /* Extract the return value from the register where it was stored. */ |
| 331 | if (readbuf) |
| 332 | regcache->raw_read_part (regnum, 0, len, readbuf); |
| 333 | if (writebuf) |
| 334 | regcache->raw_write_part (regnum, 0, len, writebuf); |
| 335 | return RETURN_VALUE_REGISTER_CONVENTION; |
| 336 | } |
| 337 | } |
| 338 | |
| 339 | /* Check that the code pointed to by PC corresponds to a call to |
| 340 | __main, skip it if so. Return PC otherwise. */ |
| 341 | |
| 342 | static CORE_ADDR |
| 343 | amd64_skip_main_prologue (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 344 | { |
| 345 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 346 | gdb_byte op; |
| 347 | |
| 348 | target_read_memory (pc, &op, 1); |
| 349 | if (op == 0xe8) |
| 350 | { |
| 351 | gdb_byte buf[4]; |
| 352 | |
| 353 | if (target_read_memory (pc + 1, buf, sizeof buf) == 0) |
| 354 | { |
| 355 | struct bound_minimal_symbol s; |
| 356 | CORE_ADDR call_dest; |
| 357 | |
| 358 | call_dest = pc + 5 + extract_signed_integer (buf, 4, byte_order); |
| 359 | s = lookup_minimal_symbol_by_pc (call_dest); |
| 360 | if (s.minsym != NULL |
| 361 | && MSYMBOL_LINKAGE_NAME (s.minsym) != NULL |
| 362 | && strcmp (MSYMBOL_LINKAGE_NAME (s.minsym), "__main") == 0) |
| 363 | pc += 5; |
| 364 | } |
| 365 | } |
| 366 | |
| 367 | return pc; |
| 368 | } |
| 369 | |
| 370 | struct amd64_windows_frame_cache |
| 371 | { |
| 372 | /* ImageBase for the module. */ |
| 373 | CORE_ADDR image_base; |
| 374 | |
| 375 | /* Function start and end rva. */ |
| 376 | CORE_ADDR start_rva; |
| 377 | CORE_ADDR end_rva; |
| 378 | |
| 379 | /* Next instruction to be executed. */ |
| 380 | CORE_ADDR pc; |
| 381 | |
| 382 | /* Current sp. */ |
| 383 | CORE_ADDR sp; |
| 384 | |
| 385 | /* Address of saved integer and xmm registers. */ |
| 386 | CORE_ADDR prev_reg_addr[16]; |
| 387 | CORE_ADDR prev_xmm_addr[16]; |
| 388 | |
| 389 | /* These two next fields are set only for machine info frames. */ |
| 390 | |
| 391 | /* Likewise for RIP. */ |
| 392 | CORE_ADDR prev_rip_addr; |
| 393 | |
| 394 | /* Likewise for RSP. */ |
| 395 | CORE_ADDR prev_rsp_addr; |
| 396 | |
| 397 | /* Address of the previous frame. */ |
| 398 | CORE_ADDR prev_sp; |
| 399 | }; |
| 400 | |
| 401 | /* Convert a Windows register number to gdb. */ |
| 402 | static const enum amd64_regnum amd64_windows_w2gdb_regnum[] = |
| 403 | { |
| 404 | AMD64_RAX_REGNUM, |
| 405 | AMD64_RCX_REGNUM, |
| 406 | AMD64_RDX_REGNUM, |
| 407 | AMD64_RBX_REGNUM, |
| 408 | AMD64_RSP_REGNUM, |
| 409 | AMD64_RBP_REGNUM, |
| 410 | AMD64_RSI_REGNUM, |
| 411 | AMD64_RDI_REGNUM, |
| 412 | AMD64_R8_REGNUM, |
| 413 | AMD64_R9_REGNUM, |
| 414 | AMD64_R10_REGNUM, |
| 415 | AMD64_R11_REGNUM, |
| 416 | AMD64_R12_REGNUM, |
| 417 | AMD64_R13_REGNUM, |
| 418 | AMD64_R14_REGNUM, |
| 419 | AMD64_R15_REGNUM |
| 420 | }; |
| 421 | |
| 422 | /* Return TRUE iff PC is the the range of the function corresponding to |
| 423 | CACHE. */ |
| 424 | |
| 425 | static int |
| 426 | pc_in_range (CORE_ADDR pc, const struct amd64_windows_frame_cache *cache) |
| 427 | { |
| 428 | return (pc >= cache->image_base + cache->start_rva |
| 429 | && pc < cache->image_base + cache->end_rva); |
| 430 | } |
| 431 | |
| 432 | /* Try to recognize and decode an epilogue sequence. |
| 433 | |
| 434 | Return -1 if we fail to read the instructions for any reason. |
| 435 | Return 1 if an epilogue sequence was recognized, 0 otherwise. */ |
| 436 | |
| 437 | static int |
| 438 | amd64_windows_frame_decode_epilogue (struct frame_info *this_frame, |
| 439 | struct amd64_windows_frame_cache *cache) |
| 440 | { |
| 441 | /* According to MSDN an epilogue "must consist of either an add RSP,constant |
| 442 | or lea RSP,constant[FPReg], followed by a series of zero or more 8-byte |
| 443 | register pops and a return or a jmp". |
| 444 | |
| 445 | Furthermore, according to RtlVirtualUnwind, the complete list of |
| 446 | epilog marker is: |
| 447 | - ret [c3] |
| 448 | - ret n [c2 imm16] |
| 449 | - rep ret [f3 c3] |
| 450 | - jmp imm8 | imm32 [eb rel8] or [e9 rel32] |
| 451 | - jmp qword ptr imm32 - not handled |
| 452 | - rex.w jmp reg [4X ff eY] |
| 453 | */ |
| 454 | |
| 455 | CORE_ADDR pc = cache->pc; |
| 456 | CORE_ADDR cur_sp = cache->sp; |
| 457 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| 458 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 459 | gdb_byte op; |
| 460 | gdb_byte rex; |
| 461 | |
| 462 | /* We don't care about the instruction deallocating the frame: |
| 463 | if it hasn't been executed, the pc is still in the body, |
| 464 | if it has been executed, the following epilog decoding will work. */ |
| 465 | |
| 466 | /* First decode: |
| 467 | - pop reg [41 58-5f] or [58-5f]. */ |
| 468 | |
| 469 | while (1) |
| 470 | { |
| 471 | /* Read opcode. */ |
| 472 | if (target_read_memory (pc, &op, 1) != 0) |
| 473 | return -1; |
| 474 | |
| 475 | if (op >= 0x40 && op <= 0x4f) |
| 476 | { |
| 477 | /* REX prefix. */ |
| 478 | rex = op; |
| 479 | |
| 480 | /* Read opcode. */ |
| 481 | if (target_read_memory (pc + 1, &op, 1) != 0) |
| 482 | return -1; |
| 483 | } |
| 484 | else |
| 485 | rex = 0; |
| 486 | |
| 487 | if (op >= 0x58 && op <= 0x5f) |
| 488 | { |
| 489 | /* pop reg */ |
| 490 | gdb_byte reg = (op & 0x0f) | ((rex & 1) << 3); |
| 491 | |
| 492 | cache->prev_reg_addr[amd64_windows_w2gdb_regnum[reg]] = cur_sp; |
| 493 | cur_sp += 8; |
| 494 | pc += rex ? 2 : 1; |
| 495 | } |
| 496 | else |
| 497 | break; |
| 498 | |
| 499 | /* Allow the user to break this loop. This shouldn't happen as the |
| 500 | number of consecutive pop should be small. */ |
| 501 | QUIT; |
| 502 | } |
| 503 | |
| 504 | /* Then decode the marker. */ |
| 505 | |
| 506 | /* Read opcode. */ |
| 507 | if (target_read_memory (pc, &op, 1) != 0) |
| 508 | return -1; |
| 509 | |
| 510 | switch (op) |
| 511 | { |
| 512 | case 0xc3: |
| 513 | /* Ret. */ |
| 514 | cache->prev_rip_addr = cur_sp; |
| 515 | cache->prev_sp = cur_sp + 8; |
| 516 | return 1; |
| 517 | |
| 518 | case 0xeb: |
| 519 | { |
| 520 | /* jmp rel8 */ |
| 521 | gdb_byte rel8; |
| 522 | CORE_ADDR npc; |
| 523 | |
| 524 | if (target_read_memory (pc + 1, &rel8, 1) != 0) |
| 525 | return -1; |
| 526 | npc = pc + 2 + (signed char) rel8; |
| 527 | |
| 528 | /* If the jump is within the function, then this is not a marker, |
| 529 | otherwise this is a tail-call. */ |
| 530 | return !pc_in_range (npc, cache); |
| 531 | } |
| 532 | |
| 533 | case 0xec: |
| 534 | { |
| 535 | /* jmp rel32 */ |
| 536 | gdb_byte rel32[4]; |
| 537 | CORE_ADDR npc; |
| 538 | |
| 539 | if (target_read_memory (pc + 1, rel32, 4) != 0) |
| 540 | return -1; |
| 541 | npc = pc + 5 + extract_signed_integer (rel32, 4, byte_order); |
| 542 | |
| 543 | /* If the jump is within the function, then this is not a marker, |
| 544 | otherwise this is a tail-call. */ |
| 545 | return !pc_in_range (npc, cache); |
| 546 | } |
| 547 | |
| 548 | case 0xc2: |
| 549 | { |
| 550 | /* ret n */ |
| 551 | gdb_byte imm16[2]; |
| 552 | |
| 553 | if (target_read_memory (pc + 1, imm16, 2) != 0) |
| 554 | return -1; |
| 555 | cache->prev_rip_addr = cur_sp; |
| 556 | cache->prev_sp = cur_sp |
| 557 | + extract_unsigned_integer (imm16, 4, byte_order); |
| 558 | return 1; |
| 559 | } |
| 560 | |
| 561 | case 0xf3: |
| 562 | { |
| 563 | /* rep; ret */ |
| 564 | gdb_byte op1; |
| 565 | |
| 566 | if (target_read_memory (pc + 2, &op1, 1) != 0) |
| 567 | return -1; |
| 568 | if (op1 != 0xc3) |
| 569 | return 0; |
| 570 | |
| 571 | cache->prev_rip_addr = cur_sp; |
| 572 | cache->prev_sp = cur_sp + 8; |
| 573 | return 1; |
| 574 | } |
| 575 | |
| 576 | case 0x40: |
| 577 | case 0x41: |
| 578 | case 0x42: |
| 579 | case 0x43: |
| 580 | case 0x44: |
| 581 | case 0x45: |
| 582 | case 0x46: |
| 583 | case 0x47: |
| 584 | case 0x48: |
| 585 | case 0x49: |
| 586 | case 0x4a: |
| 587 | case 0x4b: |
| 588 | case 0x4c: |
| 589 | case 0x4d: |
| 590 | case 0x4e: |
| 591 | case 0x4f: |
| 592 | /* Got a REX prefix, read next byte. */ |
| 593 | rex = op; |
| 594 | if (target_read_memory (pc + 1, &op, 1) != 0) |
| 595 | return -1; |
| 596 | |
| 597 | if (op == 0xff) |
| 598 | { |
| 599 | /* rex jmp reg */ |
| 600 | gdb_byte op1; |
| 601 | |
| 602 | if (target_read_memory (pc + 2, &op1, 1) != 0) |
| 603 | return -1; |
| 604 | return (op1 & 0xf8) == 0xe0; |
| 605 | } |
| 606 | else |
| 607 | return 0; |
| 608 | |
| 609 | default: |
| 610 | /* Not REX, so unknown. */ |
| 611 | return 0; |
| 612 | } |
| 613 | } |
| 614 | |
| 615 | /* Decode and execute unwind insns at UNWIND_INFO. */ |
| 616 | |
| 617 | static void |
| 618 | amd64_windows_frame_decode_insns (struct frame_info *this_frame, |
| 619 | struct amd64_windows_frame_cache *cache, |
| 620 | CORE_ADDR unwind_info) |
| 621 | { |
| 622 | CORE_ADDR save_addr = 0; |
| 623 | CORE_ADDR cur_sp = cache->sp; |
| 624 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| 625 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 626 | int first = 1; |
| 627 | |
| 628 | /* There are at least 3 possibilities to share an unwind info entry: |
| 629 | 1. Two different runtime_function entries (in .pdata) can point to the |
| 630 | same unwind info entry. There is no such indication while unwinding, |
| 631 | so we don't really care about that case. We suppose this scheme is |
| 632 | used to save memory when the unwind entries are exactly the same. |
| 633 | 2. Chained unwind_info entries, with no unwind codes (no prologue). |
| 634 | There is a major difference with the previous case: the pc range for |
| 635 | the function is different (in case 1, the pc range comes from the |
| 636 | runtime_function entry; in case 2, the pc range for the chained entry |
| 637 | comes from the first unwind entry). Case 1 cannot be used instead as |
| 638 | the pc is not in the prologue. This case is officially documented. |
| 639 | (There might be unwind code in the first unwind entry to handle |
| 640 | additional unwinding). GCC (at least until gcc 5.0) doesn't chain |
| 641 | entries. |
| 642 | 3. Undocumented unwind info redirection. Hard to know the exact purpose, |
| 643 | so it is considered as a memory optimization of case 2. |
| 644 | */ |
| 645 | |
| 646 | if (unwind_info & 1) |
| 647 | { |
| 648 | /* Unofficially documented unwind info redirection, when UNWIND_INFO |
| 649 | address is odd (http://www.codemachine.com/article_x64deepdive.html). |
| 650 | */ |
| 651 | struct external_pex64_runtime_function d; |
| 652 | |
| 653 | if (target_read_memory (cache->image_base + (unwind_info & ~1), |
| 654 | (gdb_byte *) &d, sizeof (d)) != 0) |
| 655 | return; |
| 656 | |
| 657 | cache->start_rva |
| 658 | = extract_unsigned_integer (d.rva_BeginAddress, 4, byte_order); |
| 659 | cache->end_rva |
| 660 | = extract_unsigned_integer (d.rva_EndAddress, 4, byte_order); |
| 661 | unwind_info |
| 662 | = extract_unsigned_integer (d.rva_UnwindData, 4, byte_order); |
| 663 | } |
| 664 | |
| 665 | while (1) |
| 666 | { |
| 667 | struct external_pex64_unwind_info ex_ui; |
| 668 | /* There are at most 256 16-bit unwind insns. */ |
| 669 | gdb_byte insns[2 * 256]; |
| 670 | gdb_byte *p; |
| 671 | gdb_byte *end_insns; |
| 672 | unsigned char codes_count; |
| 673 | unsigned char frame_reg; |
| 674 | CORE_ADDR start; |
| 675 | |
| 676 | /* Read and decode header. */ |
| 677 | if (target_read_memory (cache->image_base + unwind_info, |
| 678 | (gdb_byte *) &ex_ui, sizeof (ex_ui)) != 0) |
| 679 | return; |
| 680 | |
| 681 | if (frame_debug) |
| 682 | fprintf_unfiltered |
| 683 | (gdb_stdlog, |
| 684 | "amd64_windows_frame_decodes_insn: " |
| 685 | "%s: ver: %02x, plgsz: %02x, cnt: %02x, frame: %02x\n", |
| 686 | paddress (gdbarch, unwind_info), |
| 687 | ex_ui.Version_Flags, ex_ui.SizeOfPrologue, |
| 688 | ex_ui.CountOfCodes, ex_ui.FrameRegisterOffset); |
| 689 | |
| 690 | /* Check version. */ |
| 691 | if (PEX64_UWI_VERSION (ex_ui.Version_Flags) != 1 |
| 692 | && PEX64_UWI_VERSION (ex_ui.Version_Flags) != 2) |
| 693 | return; |
| 694 | |
| 695 | start = cache->image_base + cache->start_rva; |
| 696 | if (first |
| 697 | && !(cache->pc >= start && cache->pc < start + ex_ui.SizeOfPrologue)) |
| 698 | { |
| 699 | /* We want to detect if the PC points to an epilogue. This needs |
| 700 | to be checked only once, and an epilogue can be anywhere but in |
| 701 | the prologue. If so, the epilogue detection+decoding function is |
| 702 | sufficient. Otherwise, the unwinder will consider that the PC |
| 703 | is in the body of the function and will need to decode unwind |
| 704 | info. */ |
| 705 | if (amd64_windows_frame_decode_epilogue (this_frame, cache) == 1) |
| 706 | return; |
| 707 | |
| 708 | /* Not in an epilog. Clear possible side effects. */ |
| 709 | memset (cache->prev_reg_addr, 0, sizeof (cache->prev_reg_addr)); |
| 710 | } |
| 711 | |
| 712 | codes_count = ex_ui.CountOfCodes; |
| 713 | frame_reg = PEX64_UWI_FRAMEREG (ex_ui.FrameRegisterOffset); |
| 714 | |
| 715 | if (frame_reg != 0) |
| 716 | { |
| 717 | /* According to msdn: |
| 718 | If an FP reg is used, then any unwind code taking an offset must |
| 719 | only be used after the FP reg is established in the prolog. */ |
| 720 | gdb_byte buf[8]; |
| 721 | int frreg = amd64_windows_w2gdb_regnum[frame_reg]; |
| 722 | |
| 723 | get_frame_register (this_frame, frreg, buf); |
| 724 | save_addr = extract_unsigned_integer (buf, 8, byte_order); |
| 725 | |
| 726 | if (frame_debug) |
| 727 | fprintf_unfiltered (gdb_stdlog, " frame_reg=%s, val=%s\n", |
| 728 | gdbarch_register_name (gdbarch, frreg), |
| 729 | paddress (gdbarch, save_addr)); |
| 730 | } |
| 731 | |
| 732 | /* Read opcodes. */ |
| 733 | if (codes_count != 0 |
| 734 | && target_read_memory (cache->image_base + unwind_info |
| 735 | + sizeof (ex_ui), |
| 736 | insns, codes_count * 2) != 0) |
| 737 | return; |
| 738 | |
| 739 | end_insns = &insns[codes_count * 2]; |
| 740 | p = insns; |
| 741 | |
| 742 | /* Skip opcodes 6 of version 2. This opcode is not documented. */ |
| 743 | if (PEX64_UWI_VERSION (ex_ui.Version_Flags) == 2) |
| 744 | { |
| 745 | for (; p < end_insns; p += 2) |
| 746 | if (PEX64_UNWCODE_CODE (p[1]) != 6) |
| 747 | break; |
| 748 | } |
| 749 | |
| 750 | for (; p < end_insns; p += 2) |
| 751 | { |
| 752 | int reg; |
| 753 | |
| 754 | /* Virtually execute the operation if the pc is after the |
| 755 | corresponding instruction (that does matter in case of break |
| 756 | within the prologue). Note that for chained info (!first), the |
| 757 | prologue has been fully executed. */ |
| 758 | if (cache->pc >= start + p[0] || cache->pc < start) |
| 759 | { |
| 760 | if (frame_debug) |
| 761 | fprintf_unfiltered |
| 762 | (gdb_stdlog, " op #%u: off=0x%02x, insn=0x%02x\n", |
| 763 | (unsigned) (p - insns), p[0], p[1]); |
| 764 | |
| 765 | /* If there is no frame registers defined, the current value of |
| 766 | rsp is used instead. */ |
| 767 | if (frame_reg == 0) |
| 768 | save_addr = cur_sp; |
| 769 | |
| 770 | reg = -1; |
| 771 | |
| 772 | switch (PEX64_UNWCODE_CODE (p[1])) |
| 773 | { |
| 774 | case UWOP_PUSH_NONVOL: |
| 775 | /* Push pre-decrements RSP. */ |
| 776 | reg = amd64_windows_w2gdb_regnum[PEX64_UNWCODE_INFO (p[1])]; |
| 777 | cache->prev_reg_addr[reg] = cur_sp; |
| 778 | cur_sp += 8; |
| 779 | break; |
| 780 | case UWOP_ALLOC_LARGE: |
| 781 | if (PEX64_UNWCODE_INFO (p[1]) == 0) |
| 782 | cur_sp += |
| 783 | 8 * extract_unsigned_integer (p + 2, 2, byte_order); |
| 784 | else if (PEX64_UNWCODE_INFO (p[1]) == 1) |
| 785 | cur_sp += extract_unsigned_integer (p + 2, 4, byte_order); |
| 786 | else |
| 787 | return; |
| 788 | break; |
| 789 | case UWOP_ALLOC_SMALL: |
| 790 | cur_sp += 8 + 8 * PEX64_UNWCODE_INFO (p[1]); |
| 791 | break; |
| 792 | case UWOP_SET_FPREG: |
| 793 | cur_sp = save_addr |
| 794 | - PEX64_UWI_FRAMEOFF (ex_ui.FrameRegisterOffset) * 16; |
| 795 | break; |
| 796 | case UWOP_SAVE_NONVOL: |
| 797 | reg = amd64_windows_w2gdb_regnum[PEX64_UNWCODE_INFO (p[1])]; |
| 798 | cache->prev_reg_addr[reg] = save_addr |
| 799 | + 8 * extract_unsigned_integer (p + 2, 2, byte_order); |
| 800 | break; |
| 801 | case UWOP_SAVE_NONVOL_FAR: |
| 802 | reg = amd64_windows_w2gdb_regnum[PEX64_UNWCODE_INFO (p[1])]; |
| 803 | cache->prev_reg_addr[reg] = save_addr |
| 804 | + 8 * extract_unsigned_integer (p + 2, 4, byte_order); |
| 805 | break; |
| 806 | case UWOP_SAVE_XMM128: |
| 807 | cache->prev_xmm_addr[PEX64_UNWCODE_INFO (p[1])] = |
| 808 | save_addr |
| 809 | - 16 * extract_unsigned_integer (p + 2, 2, byte_order); |
| 810 | break; |
| 811 | case UWOP_SAVE_XMM128_FAR: |
| 812 | cache->prev_xmm_addr[PEX64_UNWCODE_INFO (p[1])] = |
| 813 | save_addr |
| 814 | - 16 * extract_unsigned_integer (p + 2, 4, byte_order); |
| 815 | break; |
| 816 | case UWOP_PUSH_MACHFRAME: |
| 817 | if (PEX64_UNWCODE_INFO (p[1]) == 0) |
| 818 | { |
| 819 | cache->prev_rip_addr = cur_sp + 0; |
| 820 | cache->prev_rsp_addr = cur_sp + 24; |
| 821 | cur_sp += 40; |
| 822 | } |
| 823 | else if (PEX64_UNWCODE_INFO (p[1]) == 1) |
| 824 | { |
| 825 | cache->prev_rip_addr = cur_sp + 8; |
| 826 | cache->prev_rsp_addr = cur_sp + 32; |
| 827 | cur_sp += 48; |
| 828 | } |
| 829 | else |
| 830 | return; |
| 831 | break; |
| 832 | default: |
| 833 | return; |
| 834 | } |
| 835 | |
| 836 | /* Display address where the register was saved. */ |
| 837 | if (frame_debug && reg >= 0) |
| 838 | fprintf_unfiltered |
| 839 | (gdb_stdlog, " [reg %s at %s]\n", |
| 840 | gdbarch_register_name (gdbarch, reg), |
| 841 | paddress (gdbarch, cache->prev_reg_addr[reg])); |
| 842 | } |
| 843 | |
| 844 | /* Adjust with the length of the opcode. */ |
| 845 | switch (PEX64_UNWCODE_CODE (p[1])) |
| 846 | { |
| 847 | case UWOP_PUSH_NONVOL: |
| 848 | case UWOP_ALLOC_SMALL: |
| 849 | case UWOP_SET_FPREG: |
| 850 | case UWOP_PUSH_MACHFRAME: |
| 851 | break; |
| 852 | case UWOP_ALLOC_LARGE: |
| 853 | if (PEX64_UNWCODE_INFO (p[1]) == 0) |
| 854 | p += 2; |
| 855 | else if (PEX64_UNWCODE_INFO (p[1]) == 1) |
| 856 | p += 4; |
| 857 | else |
| 858 | return; |
| 859 | break; |
| 860 | case UWOP_SAVE_NONVOL: |
| 861 | case UWOP_SAVE_XMM128: |
| 862 | p += 2; |
| 863 | break; |
| 864 | case UWOP_SAVE_NONVOL_FAR: |
| 865 | case UWOP_SAVE_XMM128_FAR: |
| 866 | p += 4; |
| 867 | break; |
| 868 | default: |
| 869 | return; |
| 870 | } |
| 871 | } |
| 872 | if (PEX64_UWI_FLAGS (ex_ui.Version_Flags) != UNW_FLAG_CHAININFO) |
| 873 | { |
| 874 | /* End of unwind info. */ |
| 875 | break; |
| 876 | } |
| 877 | else |
| 878 | { |
| 879 | /* Read the chained unwind info. */ |
| 880 | struct external_pex64_runtime_function d; |
| 881 | CORE_ADDR chain_vma; |
| 882 | |
| 883 | /* Not anymore the first entry. */ |
| 884 | first = 0; |
| 885 | |
| 886 | /* Stay aligned on word boundary. */ |
| 887 | chain_vma = cache->image_base + unwind_info |
| 888 | + sizeof (ex_ui) + ((codes_count + 1) & ~1) * 2; |
| 889 | |
| 890 | if (target_read_memory (chain_vma, (gdb_byte *) &d, sizeof (d)) != 0) |
| 891 | return; |
| 892 | |
| 893 | /* Decode begin/end. This may be different from .pdata index, as |
| 894 | an unwind info may be shared by several functions (in particular |
| 895 | if many functions have the same prolog and handler. */ |
| 896 | cache->start_rva = |
| 897 | extract_unsigned_integer (d.rva_BeginAddress, 4, byte_order); |
| 898 | cache->end_rva = |
| 899 | extract_unsigned_integer (d.rva_EndAddress, 4, byte_order); |
| 900 | unwind_info = |
| 901 | extract_unsigned_integer (d.rva_UnwindData, 4, byte_order); |
| 902 | |
| 903 | if (frame_debug) |
| 904 | fprintf_unfiltered |
| 905 | (gdb_stdlog, |
| 906 | "amd64_windows_frame_decodes_insn (next in chain):" |
| 907 | " unwind_data=%s, start_rva=%s, end_rva=%s\n", |
| 908 | paddress (gdbarch, unwind_info), |
| 909 | paddress (gdbarch, cache->start_rva), |
| 910 | paddress (gdbarch, cache->end_rva)); |
| 911 | } |
| 912 | |
| 913 | /* Allow the user to break this loop. */ |
| 914 | QUIT; |
| 915 | } |
| 916 | /* PC is saved by the call. */ |
| 917 | if (cache->prev_rip_addr == 0) |
| 918 | cache->prev_rip_addr = cur_sp; |
| 919 | cache->prev_sp = cur_sp + 8; |
| 920 | |
| 921 | if (frame_debug) |
| 922 | fprintf_unfiltered (gdb_stdlog, " prev_sp: %s, prev_pc @%s\n", |
| 923 | paddress (gdbarch, cache->prev_sp), |
| 924 | paddress (gdbarch, cache->prev_rip_addr)); |
| 925 | } |
| 926 | |
| 927 | /* Find SEH unwind info for PC, returning 0 on success. |
| 928 | |
| 929 | UNWIND_INFO is set to the rva of unwind info address, IMAGE_BASE |
| 930 | to the base address of the corresponding image, and START_RVA |
| 931 | to the rva of the function containing PC. */ |
| 932 | |
| 933 | static int |
| 934 | amd64_windows_find_unwind_info (struct gdbarch *gdbarch, CORE_ADDR pc, |
| 935 | CORE_ADDR *unwind_info, |
| 936 | CORE_ADDR *image_base, |
| 937 | CORE_ADDR *start_rva, |
| 938 | CORE_ADDR *end_rva) |
| 939 | { |
| 940 | struct obj_section *sec; |
| 941 | pe_data_type *pe; |
| 942 | IMAGE_DATA_DIRECTORY *dir; |
| 943 | struct objfile *objfile; |
| 944 | unsigned long lo, hi; |
| 945 | CORE_ADDR base; |
| 946 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 947 | |
| 948 | /* Get the corresponding exception directory. */ |
| 949 | sec = find_pc_section (pc); |
| 950 | if (sec == NULL) |
| 951 | return -1; |
| 952 | objfile = sec->objfile; |
| 953 | pe = pe_data (sec->objfile->obfd); |
| 954 | dir = &pe->pe_opthdr.DataDirectory[PE_EXCEPTION_TABLE]; |
| 955 | |
| 956 | base = pe->pe_opthdr.ImageBase |
| 957 | + ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile)); |
| 958 | *image_base = base; |
| 959 | |
| 960 | /* Find the entry. |
| 961 | |
| 962 | Note: This does not handle dynamically added entries (for JIT |
| 963 | engines). For this, we would need to ask the kernel directly, |
| 964 | which means getting some info from the native layer. For the |
| 965 | rest of the code, however, it's probably faster to search |
| 966 | the entry ourselves. */ |
| 967 | lo = 0; |
| 968 | hi = dir->Size / sizeof (struct external_pex64_runtime_function); |
| 969 | *unwind_info = 0; |
| 970 | while (lo <= hi) |
| 971 | { |
| 972 | unsigned long mid = lo + (hi - lo) / 2; |
| 973 | struct external_pex64_runtime_function d; |
| 974 | CORE_ADDR sa, ea; |
| 975 | |
| 976 | if (target_read_memory (base + dir->VirtualAddress + mid * sizeof (d), |
| 977 | (gdb_byte *) &d, sizeof (d)) != 0) |
| 978 | return -1; |
| 979 | |
| 980 | sa = extract_unsigned_integer (d.rva_BeginAddress, 4, byte_order); |
| 981 | ea = extract_unsigned_integer (d.rva_EndAddress, 4, byte_order); |
| 982 | if (pc < base + sa) |
| 983 | hi = mid - 1; |
| 984 | else if (pc >= base + ea) |
| 985 | lo = mid + 1; |
| 986 | else if (pc >= base + sa && pc < base + ea) |
| 987 | { |
| 988 | /* Got it. */ |
| 989 | *start_rva = sa; |
| 990 | *end_rva = ea; |
| 991 | *unwind_info = |
| 992 | extract_unsigned_integer (d.rva_UnwindData, 4, byte_order); |
| 993 | break; |
| 994 | } |
| 995 | else |
| 996 | break; |
| 997 | } |
| 998 | |
| 999 | if (frame_debug) |
| 1000 | fprintf_unfiltered |
| 1001 | (gdb_stdlog, |
| 1002 | "amd64_windows_find_unwind_data: image_base=%s, unwind_data=%s\n", |
| 1003 | paddress (gdbarch, base), paddress (gdbarch, *unwind_info)); |
| 1004 | |
| 1005 | return 0; |
| 1006 | } |
| 1007 | |
| 1008 | /* Fill THIS_CACHE using the native amd64-windows unwinding data |
| 1009 | for THIS_FRAME. */ |
| 1010 | |
| 1011 | static struct amd64_windows_frame_cache * |
| 1012 | amd64_windows_frame_cache (struct frame_info *this_frame, void **this_cache) |
| 1013 | { |
| 1014 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| 1015 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 1016 | struct amd64_windows_frame_cache *cache; |
| 1017 | gdb_byte buf[8]; |
| 1018 | CORE_ADDR pc; |
| 1019 | CORE_ADDR unwind_info = 0; |
| 1020 | |
| 1021 | if (*this_cache) |
| 1022 | return (struct amd64_windows_frame_cache *) *this_cache; |
| 1023 | |
| 1024 | cache = FRAME_OBSTACK_ZALLOC (struct amd64_windows_frame_cache); |
| 1025 | *this_cache = cache; |
| 1026 | |
| 1027 | /* Get current PC and SP. */ |
| 1028 | pc = get_frame_pc (this_frame); |
| 1029 | get_frame_register (this_frame, AMD64_RSP_REGNUM, buf); |
| 1030 | cache->sp = extract_unsigned_integer (buf, 8, byte_order); |
| 1031 | cache->pc = pc; |
| 1032 | |
| 1033 | if (amd64_windows_find_unwind_info (gdbarch, pc, &unwind_info, |
| 1034 | &cache->image_base, |
| 1035 | &cache->start_rva, |
| 1036 | &cache->end_rva)) |
| 1037 | return cache; |
| 1038 | |
| 1039 | if (unwind_info == 0) |
| 1040 | { |
| 1041 | /* Assume a leaf function. */ |
| 1042 | cache->prev_sp = cache->sp + 8; |
| 1043 | cache->prev_rip_addr = cache->sp; |
| 1044 | } |
| 1045 | else |
| 1046 | { |
| 1047 | /* Decode unwind insns to compute saved addresses. */ |
| 1048 | amd64_windows_frame_decode_insns (this_frame, cache, unwind_info); |
| 1049 | } |
| 1050 | return cache; |
| 1051 | } |
| 1052 | |
| 1053 | /* Implement the "prev_register" method of struct frame_unwind |
| 1054 | using the standard Windows x64 SEH info. */ |
| 1055 | |
| 1056 | static struct value * |
| 1057 | amd64_windows_frame_prev_register (struct frame_info *this_frame, |
| 1058 | void **this_cache, int regnum) |
| 1059 | { |
| 1060 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| 1061 | struct amd64_windows_frame_cache *cache = |
| 1062 | amd64_windows_frame_cache (this_frame, this_cache); |
| 1063 | CORE_ADDR prev; |
| 1064 | |
| 1065 | if (frame_debug) |
| 1066 | fprintf_unfiltered (gdb_stdlog, |
| 1067 | "amd64_windows_frame_prev_register %s for sp=%s\n", |
| 1068 | gdbarch_register_name (gdbarch, regnum), |
| 1069 | paddress (gdbarch, cache->prev_sp)); |
| 1070 | |
| 1071 | if (regnum >= AMD64_XMM0_REGNUM && regnum <= AMD64_XMM0_REGNUM + 15) |
| 1072 | prev = cache->prev_xmm_addr[regnum - AMD64_XMM0_REGNUM]; |
| 1073 | else if (regnum == AMD64_RSP_REGNUM) |
| 1074 | { |
| 1075 | prev = cache->prev_rsp_addr; |
| 1076 | if (prev == 0) |
| 1077 | return frame_unwind_got_constant (this_frame, regnum, cache->prev_sp); |
| 1078 | } |
| 1079 | else if (regnum >= AMD64_RAX_REGNUM && regnum <= AMD64_R15_REGNUM) |
| 1080 | prev = cache->prev_reg_addr[regnum - AMD64_RAX_REGNUM]; |
| 1081 | else if (regnum == AMD64_RIP_REGNUM) |
| 1082 | prev = cache->prev_rip_addr; |
| 1083 | else |
| 1084 | prev = 0; |
| 1085 | |
| 1086 | if (prev && frame_debug) |
| 1087 | fprintf_unfiltered (gdb_stdlog, " -> at %s\n", paddress (gdbarch, prev)); |
| 1088 | |
| 1089 | if (prev) |
| 1090 | { |
| 1091 | /* Register was saved. */ |
| 1092 | return frame_unwind_got_memory (this_frame, regnum, prev); |
| 1093 | } |
| 1094 | else |
| 1095 | { |
| 1096 | /* Register is either volatile or not modified. */ |
| 1097 | return frame_unwind_got_register (this_frame, regnum, regnum); |
| 1098 | } |
| 1099 | } |
| 1100 | |
| 1101 | /* Implement the "this_id" method of struct frame_unwind using |
| 1102 | the standard Windows x64 SEH info. */ |
| 1103 | |
| 1104 | static void |
| 1105 | amd64_windows_frame_this_id (struct frame_info *this_frame, void **this_cache, |
| 1106 | struct frame_id *this_id) |
| 1107 | { |
| 1108 | struct amd64_windows_frame_cache *cache = |
| 1109 | amd64_windows_frame_cache (this_frame, this_cache); |
| 1110 | |
| 1111 | *this_id = frame_id_build (cache->prev_sp, |
| 1112 | cache->image_base + cache->start_rva); |
| 1113 | } |
| 1114 | |
| 1115 | /* Windows x64 SEH unwinder. */ |
| 1116 | |
| 1117 | static const struct frame_unwind amd64_windows_frame_unwind = |
| 1118 | { |
| 1119 | NORMAL_FRAME, |
| 1120 | default_frame_unwind_stop_reason, |
| 1121 | &amd64_windows_frame_this_id, |
| 1122 | &amd64_windows_frame_prev_register, |
| 1123 | NULL, |
| 1124 | default_frame_sniffer |
| 1125 | }; |
| 1126 | |
| 1127 | /* Implement the "skip_prologue" gdbarch method. */ |
| 1128 | |
| 1129 | static CORE_ADDR |
| 1130 | amd64_windows_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 1131 | { |
| 1132 | CORE_ADDR func_addr; |
| 1133 | CORE_ADDR unwind_info = 0; |
| 1134 | CORE_ADDR image_base, start_rva, end_rva; |
| 1135 | struct external_pex64_unwind_info ex_ui; |
| 1136 | |
| 1137 | /* Use prologue size from unwind info. */ |
| 1138 | if (amd64_windows_find_unwind_info (gdbarch, pc, &unwind_info, |
| 1139 | &image_base, &start_rva, &end_rva) == 0) |
| 1140 | { |
| 1141 | if (unwind_info == 0) |
| 1142 | { |
| 1143 | /* Leaf function. */ |
| 1144 | return pc; |
| 1145 | } |
| 1146 | else if (target_read_memory (image_base + unwind_info, |
| 1147 | (gdb_byte *) &ex_ui, sizeof (ex_ui)) == 0 |
| 1148 | && PEX64_UWI_VERSION (ex_ui.Version_Flags) == 1) |
| 1149 | return std::max (pc, image_base + start_rva + ex_ui.SizeOfPrologue); |
| 1150 | } |
| 1151 | |
| 1152 | /* See if we can determine the end of the prologue via the symbol |
| 1153 | table. If so, then return either the PC, or the PC after |
| 1154 | the prologue, whichever is greater. */ |
| 1155 | if (find_pc_partial_function (pc, NULL, &func_addr, NULL)) |
| 1156 | { |
| 1157 | CORE_ADDR post_prologue_pc |
| 1158 | = skip_prologue_using_sal (gdbarch, func_addr); |
| 1159 | |
| 1160 | if (post_prologue_pc != 0) |
| 1161 | return std::max (pc, post_prologue_pc); |
| 1162 | } |
| 1163 | |
| 1164 | return pc; |
| 1165 | } |
| 1166 | |
| 1167 | /* Check Win64 DLL jmp trampolines and find jump destination. */ |
| 1168 | |
| 1169 | static CORE_ADDR |
| 1170 | amd64_windows_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc) |
| 1171 | { |
| 1172 | CORE_ADDR destination = 0; |
| 1173 | struct gdbarch *gdbarch = get_frame_arch (frame); |
| 1174 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 1175 | |
| 1176 | /* Check for jmp *<offset>(%rip) (jump near, absolute indirect (/4)). */ |
| 1177 | if (pc && read_memory_unsigned_integer (pc, 2, byte_order) == 0x25ff) |
| 1178 | { |
| 1179 | /* Get opcode offset and see if we can find a reference in our data. */ |
| 1180 | ULONGEST offset |
| 1181 | = read_memory_unsigned_integer (pc + 2, 4, byte_order); |
| 1182 | |
| 1183 | /* Get address of function pointer at end of pc. */ |
| 1184 | CORE_ADDR indirect_addr = pc + offset + 6; |
| 1185 | |
| 1186 | struct minimal_symbol *indsym |
| 1187 | = (indirect_addr |
| 1188 | ? lookup_minimal_symbol_by_pc (indirect_addr).minsym |
| 1189 | : NULL); |
| 1190 | const char *symname = indsym ? MSYMBOL_LINKAGE_NAME (indsym) : NULL; |
| 1191 | |
| 1192 | if (symname) |
| 1193 | { |
| 1194 | if (startswith (symname, "__imp_") |
| 1195 | || startswith (symname, "_imp_")) |
| 1196 | destination |
| 1197 | = read_memory_unsigned_integer (indirect_addr, 8, byte_order); |
| 1198 | } |
| 1199 | } |
| 1200 | |
| 1201 | return destination; |
| 1202 | } |
| 1203 | |
| 1204 | /* Implement the "auto_wide_charset" gdbarch method. */ |
| 1205 | |
| 1206 | static const char * |
| 1207 | amd64_windows_auto_wide_charset (void) |
| 1208 | { |
| 1209 | return "UTF-16"; |
| 1210 | } |
| 1211 | |
| 1212 | static void |
| 1213 | amd64_windows_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 1214 | { |
| 1215 | /* The dwarf2 unwinder (appended very early by i386_gdbarch_init) is |
| 1216 | preferred over the SEH one. The reasons are: |
| 1217 | - binaries without SEH but with dwarf2 debug info are correcly handled |
| 1218 | (although they aren't ABI compliant, gcc before 4.7 didn't emit SEH |
| 1219 | info). |
| 1220 | - dwarf3 DW_OP_call_frame_cfa is correctly handled (it can only be |
| 1221 | handled if the dwarf2 unwinder is used). |
| 1222 | |
| 1223 | The call to amd64_init_abi appends default unwinders, that aren't |
| 1224 | compatible with the SEH one. |
| 1225 | */ |
| 1226 | frame_unwind_append_unwinder (gdbarch, &amd64_windows_frame_unwind); |
| 1227 | |
| 1228 | amd64_init_abi (info, gdbarch, |
| 1229 | amd64_target_description (X86_XSTATE_SSE_MASK)); |
| 1230 | |
| 1231 | windows_init_abi (info, gdbarch); |
| 1232 | |
| 1233 | /* On Windows, "long"s are only 32bit. */ |
| 1234 | set_gdbarch_long_bit (gdbarch, 32); |
| 1235 | |
| 1236 | /* Function calls. */ |
| 1237 | set_gdbarch_push_dummy_call (gdbarch, amd64_windows_push_dummy_call); |
| 1238 | set_gdbarch_return_value (gdbarch, amd64_windows_return_value); |
| 1239 | set_gdbarch_skip_main_prologue (gdbarch, amd64_skip_main_prologue); |
| 1240 | set_gdbarch_skip_trampoline_code (gdbarch, |
| 1241 | amd64_windows_skip_trampoline_code); |
| 1242 | |
| 1243 | set_gdbarch_skip_prologue (gdbarch, amd64_windows_skip_prologue); |
| 1244 | |
| 1245 | set_gdbarch_auto_wide_charset (gdbarch, amd64_windows_auto_wide_charset); |
| 1246 | } |
| 1247 | |
| 1248 | void |
| 1249 | _initialize_amd64_windows_tdep (void) |
| 1250 | { |
| 1251 | gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64, GDB_OSABI_CYGWIN, |
| 1252 | amd64_windows_init_abi); |
| 1253 | } |