| 1 | /* Native-dependent code for Linux running on i386's, for GDB. |
| 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 2 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, write to the Free Software |
| 17 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 18 | |
| 19 | #include "defs.h" |
| 20 | #include "inferior.h" |
| 21 | #include "gdbcore.h" |
| 22 | |
| 23 | /* For i386_linux_skip_solib_resolver */ |
| 24 | #include "symtab.h" |
| 25 | #include "frame.h" |
| 26 | #include "symfile.h" |
| 27 | #include "objfiles.h" |
| 28 | |
| 29 | #include <sys/ptrace.h> |
| 30 | #include <sys/user.h> |
| 31 | #include <sys/procfs.h> |
| 32 | |
| 33 | #ifdef HAVE_SYS_REG_H |
| 34 | #include <sys/reg.h> |
| 35 | #endif |
| 36 | |
| 37 | /* |
| 38 | * Some systems (Linux) may have threads implemented as pseudo-processes, |
| 39 | * in which case we may be tracing more than one process at a time. |
| 40 | * In that case, inferior_pid will contain the main process ID and the |
| 41 | * individual thread (process) id mashed together. These macros are |
| 42 | * used to separate them out. The definitions may be overridden in tm.h |
| 43 | */ |
| 44 | |
| 45 | #if !defined (PIDGET) /* Default definition for PIDGET/TIDGET. */ |
| 46 | #define PIDGET(PID) PID |
| 47 | #define TIDGET(PID) 0 |
| 48 | #endif |
| 49 | |
| 50 | /* This is a duplicate of the table in i386-xdep.c. */ |
| 51 | |
| 52 | static int regmap[] = |
| 53 | { |
| 54 | EAX, ECX, EDX, EBX, |
| 55 | UESP, EBP, ESI, EDI, |
| 56 | EIP, EFL, CS, SS, |
| 57 | DS, ES, FS, GS, |
| 58 | }; |
| 59 | |
| 60 | |
| 61 | /* Which ptrace request retrieves which registers? |
| 62 | These apply to the corresponding SET requests as well. */ |
| 63 | #define GETREGS_SUPPLIES(regno) \ |
| 64 | (0 <= (regno) && (regno) <= 15) |
| 65 | #define GETFPREGS_SUPPLIES(regno) \ |
| 66 | (FP0_REGNUM <= (regno) && (regno) <= LAST_FPU_CTRL_REGNUM) |
| 67 | #define GETXFPREGS_SUPPLIES(regno) \ |
| 68 | (FP0_REGNUM <= (regno) && (regno) <= MXCSR_REGNUM) |
| 69 | |
| 70 | /* Does the current host support the GETXFPREGS request? The header |
| 71 | file may or may not define it, and even if it is defined, the |
| 72 | kernel will return EIO if it's running on a pre-SSE processor. |
| 73 | |
| 74 | PTRACE_GETXFPREGS is a Cygnus invention, since we wrote our own |
| 75 | Linux kernel patch for SSE support. That patch may or may not |
| 76 | actually make it into the official distribution. If you find that |
| 77 | years have gone by since this stuff was added, and Linux isn't |
| 78 | using PTRACE_GETXFPREGS, that means that our patch didn't make it, |
| 79 | and you can delete this, and the related code. |
| 80 | |
| 81 | My instinct is to attach this to some architecture- or |
| 82 | target-specific data structure, but really, a particular GDB |
| 83 | process can only run on top of one kernel at a time. So it's okay |
| 84 | for this to be a simple variable. */ |
| 85 | int have_ptrace_getxfpregs = |
| 86 | #ifdef HAVE_PTRACE_GETXFPREGS |
| 87 | 1 |
| 88 | #else |
| 89 | 0 |
| 90 | #endif |
| 91 | ; |
| 92 | |
| 93 | |
| 94 | \f |
| 95 | /* Transfering the general registers between GDB, inferiors and core files. */ |
| 96 | |
| 97 | /* Given a pointer to a general register set in struct user format |
| 98 | (gregset_t *), unpack the register contents and supply them as |
| 99 | gdb's idea of the current register values. */ |
| 100 | void |
| 101 | supply_gregset (gregsetp) |
| 102 | gregset_t *gregsetp; |
| 103 | { |
| 104 | register int regi; |
| 105 | register greg_t *regp = (greg_t *) gregsetp; |
| 106 | |
| 107 | for (regi = 0; regi < NUM_GREGS; regi++) |
| 108 | { |
| 109 | supply_register (regi, (char *) (regp + regmap[regi])); |
| 110 | } |
| 111 | } |
| 112 | |
| 113 | |
| 114 | /* Fill in a gregset_t object with selected data from a gdb-format |
| 115 | register file. |
| 116 | - GREGSETP points to the gregset_t object to be filled. |
| 117 | - GDB_REGS points to the GDB-style register file providing the data. |
| 118 | - VALID is an array indicating which registers in GDB_REGS are |
| 119 | valid; the parts of *GREGSETP that would hold registers marked |
| 120 | invalid in GDB_REGS are left unchanged. If VALID is zero, all |
| 121 | registers are assumed to be valid. */ |
| 122 | void |
| 123 | convert_to_gregset (gregset_t *gregsetp, |
| 124 | char *gdb_regs, |
| 125 | signed char *valid) |
| 126 | { |
| 127 | int regi; |
| 128 | register greg_t *regp = (greg_t *) gregsetp; |
| 129 | |
| 130 | for (regi = 0; regi < NUM_GREGS; regi++) |
| 131 | if (! valid || valid[regi]) |
| 132 | *(regp + regmap[regi]) = * (int *) ®isters[REGISTER_BYTE (regi)]; |
| 133 | } |
| 134 | |
| 135 | |
| 136 | /* Store GDB's value for REGNO in *GREGSETP. If REGNO is -1, do all |
| 137 | of them. */ |
| 138 | void |
| 139 | fill_gregset (gregset_t *gregsetp, |
| 140 | int regno) |
| 141 | { |
| 142 | if (regno == -1) |
| 143 | convert_to_gregset (gregsetp, registers, 0); |
| 144 | else if (regno >= 0 && regno < NUM_GREGS) |
| 145 | { |
| 146 | signed char valid[NUM_GREGS]; |
| 147 | memset (valid, 0, sizeof (valid)); |
| 148 | valid[regno] = 1; |
| 149 | convert_to_gregset (gregsetp, registers, valid); |
| 150 | } |
| 151 | } |
| 152 | |
| 153 | |
| 154 | /* Read the general registers from the process, and store them |
| 155 | in registers[]. */ |
| 156 | static void |
| 157 | fetch_regs (int tid) |
| 158 | { |
| 159 | int ret, regno; |
| 160 | gregset_t buf; |
| 161 | |
| 162 | ret = ptrace (PTRACE_GETREGS, tid, 0, (int) &buf); |
| 163 | if (ret < 0) |
| 164 | { |
| 165 | warning ("Couldn't get registers"); |
| 166 | return; |
| 167 | } |
| 168 | |
| 169 | supply_gregset (&buf); |
| 170 | } |
| 171 | |
| 172 | |
| 173 | /* Set the inferior's general registers to the values in registers[] |
| 174 | --- but only those registers marked as valid. */ |
| 175 | static void |
| 176 | store_regs (int tid) |
| 177 | { |
| 178 | int ret, regno; |
| 179 | gregset_t buf; |
| 180 | |
| 181 | ret = ptrace (PTRACE_GETREGS, tid, 0, (int) &buf); |
| 182 | if (ret < 0) |
| 183 | { |
| 184 | warning ("Couldn't get registers"); |
| 185 | return; |
| 186 | } |
| 187 | |
| 188 | convert_to_gregset (&buf, registers, register_valid); |
| 189 | |
| 190 | ret = ptrace (PTRACE_SETREGS, tid, 0, (int)buf); |
| 191 | if (ret < 0) |
| 192 | { |
| 193 | warning ("Couldn't write registers"); |
| 194 | return; |
| 195 | } |
| 196 | } |
| 197 | |
| 198 | |
| 199 | \f |
| 200 | /* Transfering floating-point registers between GDB, inferiors and cores. */ |
| 201 | |
| 202 | /* What is the address of st(N) within the fpregset_t structure F? */ |
| 203 | #define FPREGSET_T_FPREG_ADDR(f, n) \ |
| 204 | ((char *) &(f)->st_space + (n) * 10) |
| 205 | |
| 206 | /* Fill GDB's register file with the floating-point register values in |
| 207 | *FPREGSETP. */ |
| 208 | void |
| 209 | supply_fpregset (fpregset_t *fpregsetp) |
| 210 | { |
| 211 | int i; |
| 212 | |
| 213 | /* Supply the floating-point registers. */ |
| 214 | for (i = 0; i < 8; i++) |
| 215 | supply_register (FP0_REGNUM + i, FPREGSET_T_FPREG_ADDR (fpregsetp, i)); |
| 216 | |
| 217 | supply_register (FCTRL_REGNUM, (char *) &fpregsetp->cwd); |
| 218 | supply_register (FSTAT_REGNUM, (char *) &fpregsetp->swd); |
| 219 | supply_register (FTAG_REGNUM, (char *) &fpregsetp->twd); |
| 220 | supply_register (FCOFF_REGNUM, (char *) &fpregsetp->fip); |
| 221 | supply_register (FDS_REGNUM, (char *) &fpregsetp->fos); |
| 222 | supply_register (FDOFF_REGNUM, (char *) &fpregsetp->foo); |
| 223 | |
| 224 | /* Extract the code segment and opcode from the "fcs" member. */ |
| 225 | { |
| 226 | long l; |
| 227 | |
| 228 | l = fpregsetp->fcs & 0xffff; |
| 229 | supply_register (FCS_REGNUM, (char *) &l); |
| 230 | |
| 231 | l = (fpregsetp->fcs >> 16) & ((1 << 11) - 1); |
| 232 | supply_register (FOP_REGNUM, (char *) &l); |
| 233 | } |
| 234 | } |
| 235 | |
| 236 | |
| 237 | /* Fill in an fpregset_t structure with selected data from a |
| 238 | gdb-format register file. |
| 239 | - FPREGSETP points to the structure to be filled. |
| 240 | - GDB_REGS points to the GDB-style register file providing the data. |
| 241 | - VALID is an array indicating which registers in GDB_REGS are |
| 242 | valid; the parts of *FPREGSETP that would hold registers marked |
| 243 | invalid in GDB_REGS are left unchanged. If VALID is zero, all |
| 244 | registers are assumed to be valid. */ |
| 245 | void |
| 246 | convert_to_fpregset (fpregset_t *fpregsetp, |
| 247 | char *gdb_regs, |
| 248 | signed char *valid) |
| 249 | { |
| 250 | int i; |
| 251 | |
| 252 | /* Fill in the floating-point registers. */ |
| 253 | for (i = 0; i < 8; i++) |
| 254 | if (!valid || valid[i]) |
| 255 | memcpy (FPREGSET_T_FPREG_ADDR (fpregsetp, i), |
| 256 | ®isters[REGISTER_BYTE (FP0_REGNUM + i)], |
| 257 | REGISTER_RAW_SIZE(FP0_REGNUM + i)); |
| 258 | |
| 259 | #define fill(MEMBER, REGNO) \ |
| 260 | if (! valid || valid[(REGNO)]) \ |
| 261 | memcpy (&fpregsetp->MEMBER, ®isters[REGISTER_BYTE (REGNO)], \ |
| 262 | sizeof (fpregsetp->MEMBER)) |
| 263 | |
| 264 | fill (cwd, FCTRL_REGNUM); |
| 265 | fill (swd, FSTAT_REGNUM); |
| 266 | fill (twd, FTAG_REGNUM); |
| 267 | fill (fip, FCOFF_REGNUM); |
| 268 | fill (foo, FDOFF_REGNUM); |
| 269 | fill (fos, FDS_REGNUM); |
| 270 | |
| 271 | #undef fill |
| 272 | |
| 273 | if (! valid || valid[FCS_REGNUM]) |
| 274 | fpregsetp->fcs |
| 275 | = ((fpregsetp->fcs & ~0xffff) |
| 276 | | (* (int *) ®isters[REGISTER_BYTE (FCS_REGNUM)] & 0xffff)); |
| 277 | |
| 278 | if (! valid || valid[FOP_REGNUM]) |
| 279 | fpregsetp->fcs |
| 280 | = ((fpregsetp->fcs & 0xffff) |
| 281 | | ((*(int *) ®isters[REGISTER_BYTE (FOP_REGNUM)] & ((1 << 11) - 1)) |
| 282 | << 16)); |
| 283 | } |
| 284 | |
| 285 | |
| 286 | /* Given a pointer to a floating point register set in (fpregset_t *) |
| 287 | format, update all of the registers from gdb's idea of the current |
| 288 | floating point register set. */ |
| 289 | |
| 290 | void |
| 291 | fill_fpregset (fpregset_t *fpregsetp, |
| 292 | int regno) |
| 293 | { |
| 294 | convert_to_fpregset (fpregsetp, registers, 0); |
| 295 | } |
| 296 | |
| 297 | |
| 298 | /* Get the whole floating point state of the process and store the |
| 299 | floating point stack into registers[]. */ |
| 300 | static void |
| 301 | fetch_fpregs (int tid) |
| 302 | { |
| 303 | int ret, regno; |
| 304 | fpregset_t buf; |
| 305 | |
| 306 | ret = ptrace (PTRACE_GETFPREGS, tid, 0, (int) &buf); |
| 307 | if (ret < 0) |
| 308 | { |
| 309 | warning ("Couldn't get floating point status"); |
| 310 | return; |
| 311 | } |
| 312 | |
| 313 | /* ptrace fills an fpregset_t, so we can use the same function we do |
| 314 | for core files. */ |
| 315 | supply_fpregset (&buf); |
| 316 | } |
| 317 | |
| 318 | |
| 319 | /* Set the inferior's floating-point registers to the values in |
| 320 | registers[] --- but only those registers marked valid. */ |
| 321 | static void |
| 322 | store_fpregs (int tid) |
| 323 | { |
| 324 | int ret; |
| 325 | fpregset_t buf; |
| 326 | |
| 327 | ret = ptrace (PTRACE_GETFPREGS, tid, 0, (int) &buf); |
| 328 | if (ret < 0) |
| 329 | { |
| 330 | warning ("Couldn't get floating point status"); |
| 331 | return; |
| 332 | } |
| 333 | |
| 334 | convert_to_fpregset (&buf, registers, register_valid); |
| 335 | |
| 336 | ret = ptrace (PTRACE_SETFPREGS, tid, 0, (int) &buf); |
| 337 | if (ret < 0) |
| 338 | { |
| 339 | warning ("Couldn't write floating point status"); |
| 340 | return; |
| 341 | } |
| 342 | } |
| 343 | |
| 344 | \f |
| 345 | /* Transfering floating-point and SSE registers to and from GDB. */ |
| 346 | |
| 347 | |
| 348 | /* PTRACE_GETXFPREGS is a Cygnus invention, since we wrote our own |
| 349 | Linux kernel patch for SSE support. That patch may or may not |
| 350 | actually make it into the official distribution. If you find that |
| 351 | years have gone by since this code was added, and Linux isn't using |
| 352 | PTRACE_GETXFPREGS, that means that our patch didn't make it, and |
| 353 | you can delete this code. */ |
| 354 | |
| 355 | #ifdef HAVE_PTRACE_GETXFPREGS |
| 356 | static void |
| 357 | supply_xfpregset (struct user_xfpregs_struct *xfpregs) |
| 358 | { |
| 359 | int reg; |
| 360 | |
| 361 | /* Supply the floating-point registers. */ |
| 362 | for (reg = 0; reg < 8; reg++) |
| 363 | supply_register (FP0_REGNUM + reg, (char *) &xfpregs->st_space[reg]); |
| 364 | |
| 365 | { |
| 366 | supply_register (FCTRL_REGNUM, (char *) &xfpregs->cwd); |
| 367 | supply_register (FSTAT_REGNUM, (char *) &xfpregs->swd); |
| 368 | supply_register (FTAG_REGNUM, (char *) &xfpregs->twd); |
| 369 | supply_register (FCOFF_REGNUM, (char *) &xfpregs->fip); |
| 370 | supply_register (FDS_REGNUM, (char *) &xfpregs->fos); |
| 371 | supply_register (FDOFF_REGNUM, (char *) &xfpregs->foo); |
| 372 | |
| 373 | /* Extract the code segment and opcode from the "fcs" member. */ |
| 374 | { |
| 375 | long l; |
| 376 | |
| 377 | l = xfpregs->fcs & 0xffff; |
| 378 | supply_register (FCS_REGNUM, (char *) &l); |
| 379 | |
| 380 | l = (xfpregs->fcs >> 16) & ((1 << 11) - 1); |
| 381 | supply_register (FOP_REGNUM, (char *) &l); |
| 382 | } |
| 383 | } |
| 384 | |
| 385 | /* Supply the SSE registers. */ |
| 386 | for (reg = 0; reg < 8; reg++) |
| 387 | supply_register (XMM0_REGNUM + reg, (char *) &xfpregs->xmm_space[reg]); |
| 388 | supply_register (MXCSR_REGNUM, (char *) &xfpregs->mxcsr); |
| 389 | } |
| 390 | |
| 391 | |
| 392 | static void |
| 393 | convert_to_xfpregset (struct user_xfpregs_struct *xfpregs, |
| 394 | char *gdb_regs, |
| 395 | signed char *valid) |
| 396 | { |
| 397 | int reg; |
| 398 | |
| 399 | /* Fill in the floating-point registers. */ |
| 400 | for (reg = 0; reg < 8; reg++) |
| 401 | if (!valid || valid[reg]) |
| 402 | memcpy (&xfpregs->st_space[reg], |
| 403 | ®isters[REGISTER_BYTE (FP0_REGNUM + reg)], |
| 404 | REGISTER_RAW_SIZE(FP0_REGNUM + reg)); |
| 405 | |
| 406 | #define fill(MEMBER, REGNO) \ |
| 407 | if (! valid || valid[(REGNO)]) \ |
| 408 | memcpy (&xfpregs->MEMBER, ®isters[REGISTER_BYTE (REGNO)], \ |
| 409 | sizeof (xfpregs->MEMBER)) |
| 410 | |
| 411 | fill (cwd, FCTRL_REGNUM); |
| 412 | fill (swd, FSTAT_REGNUM); |
| 413 | fill (twd, FTAG_REGNUM); |
| 414 | fill (fip, FCOFF_REGNUM); |
| 415 | fill (foo, FDOFF_REGNUM); |
| 416 | fill (fos, FDS_REGNUM); |
| 417 | |
| 418 | #undef fill |
| 419 | |
| 420 | if (! valid || valid[FCS_REGNUM]) |
| 421 | xfpregs->fcs |
| 422 | = ((xfpregs->fcs & ~0xffff) |
| 423 | | (* (int *) ®isters[REGISTER_BYTE (FCS_REGNUM)] & 0xffff)); |
| 424 | |
| 425 | if (! valid || valid[FOP_REGNUM]) |
| 426 | xfpregs->fcs |
| 427 | = ((xfpregs->fcs & 0xffff) |
| 428 | | ((*(int *) ®isters[REGISTER_BYTE (FOP_REGNUM)] & ((1 << 11) - 1)) |
| 429 | << 16)); |
| 430 | |
| 431 | /* Fill in the XMM registers. */ |
| 432 | for (reg = 0; reg < 8; reg++) |
| 433 | if (! valid || valid[reg]) |
| 434 | memcpy (&xfpregs->xmm_space[reg], |
| 435 | ®isters[REGISTER_BYTE (XMM0_REGNUM + reg)], |
| 436 | REGISTER_RAW_SIZE (XMM0_REGNUM + reg)); |
| 437 | } |
| 438 | |
| 439 | |
| 440 | /* Make a PTRACE_GETXFPREGS request, and supply all the register |
| 441 | values that yields to GDB. */ |
| 442 | static int |
| 443 | fetch_xfpregs (int tid) |
| 444 | { |
| 445 | int ret; |
| 446 | struct user_xfpregs_struct xfpregs; |
| 447 | |
| 448 | if (! have_ptrace_getxfpregs) |
| 449 | return 0; |
| 450 | |
| 451 | ret = ptrace (PTRACE_GETXFPREGS, tid, 0, &xfpregs); |
| 452 | if (ret == -1) |
| 453 | { |
| 454 | if (errno == EIO) |
| 455 | { |
| 456 | have_ptrace_getxfpregs = 0; |
| 457 | return 0; |
| 458 | } |
| 459 | |
| 460 | warning ("couldn't read floating-point and SSE registers."); |
| 461 | return 0; |
| 462 | } |
| 463 | |
| 464 | supply_xfpregset (&xfpregs); |
| 465 | return 1; |
| 466 | } |
| 467 | |
| 468 | |
| 469 | /* Send all the valid register values in GDB's register file covered |
| 470 | by the PTRACE_SETXFPREGS request to the inferior. */ |
| 471 | static int |
| 472 | store_xfpregs (int tid) |
| 473 | { |
| 474 | int ret; |
| 475 | struct user_xfpregs_struct xfpregs; |
| 476 | |
| 477 | if (! have_ptrace_getxfpregs) |
| 478 | return 0; |
| 479 | |
| 480 | ret = ptrace (PTRACE_GETXFPREGS, tid, 0, &xfpregs); |
| 481 | if (ret == -1) |
| 482 | { |
| 483 | if (errno == EIO) |
| 484 | { |
| 485 | have_ptrace_getxfpregs = 0; |
| 486 | return 0; |
| 487 | } |
| 488 | |
| 489 | warning ("couldn't read floating-point and SSE registers."); |
| 490 | return 0; |
| 491 | } |
| 492 | |
| 493 | convert_to_xfpregset (&xfpregs, registers, register_valid); |
| 494 | |
| 495 | if (ptrace (PTRACE_SETXFPREGS, tid, 0, &xfpregs) < 0) |
| 496 | { |
| 497 | warning ("Couldn't write floating-point and SSE registers."); |
| 498 | return 0; |
| 499 | } |
| 500 | |
| 501 | return 1; |
| 502 | } |
| 503 | |
| 504 | |
| 505 | /* Fill the XMM registers in the register file with dummy values. For |
| 506 | cases where we don't have access to the XMM registers. I think |
| 507 | this is cleaner than printing a warning. For a cleaner solution, |
| 508 | we should gdbarchify the i386 family. */ |
| 509 | static void |
| 510 | dummy_sse_values () |
| 511 | { |
| 512 | /* C doesn't have a syntax for NaN's, so write it out as an array of |
| 513 | longs. */ |
| 514 | static long dummy[4] = { 0xffffffff, 0xffffffff, 0xffffffff, 0xffffffff }; |
| 515 | static long mxcsr = 0x1f80; |
| 516 | int reg; |
| 517 | |
| 518 | for (reg = 0; reg < 8; reg++) |
| 519 | supply_register (XMM0_REGNUM + reg, (char *) dummy); |
| 520 | supply_register (MXCSR_REGNUM, (char *) &mxcsr); |
| 521 | } |
| 522 | |
| 523 | #else |
| 524 | |
| 525 | /* Stub versions of the above routines, for systems that don't have |
| 526 | PTRACE_GETXFPREGS. */ |
| 527 | static int store_xfpregs (int tid) { return 0; } |
| 528 | static int fetch_xfpregs (int tid) { return 0; } |
| 529 | static void dummy_sse_values () {} |
| 530 | |
| 531 | #endif |
| 532 | |
| 533 | \f |
| 534 | /* Transferring arbitrary registers between GDB and inferior. */ |
| 535 | |
| 536 | /* Fetch registers from the child process. |
| 537 | Fetch all if regno == -1, otherwise fetch all ordinary |
| 538 | registers or all floating point registers depending |
| 539 | upon the value of regno. */ |
| 540 | |
| 541 | void |
| 542 | fetch_inferior_registers (int regno) |
| 543 | { |
| 544 | /* linux lwp id's are process id's */ |
| 545 | int tid; |
| 546 | |
| 547 | if ((tid = TIDGET (inferior_pid)) == 0) |
| 548 | tid = inferior_pid; /* not a threaded program */ |
| 549 | |
| 550 | /* Use the xfpregs requests whenever possible, since they transfer |
| 551 | more registers in one system call, and we'll cache the results. |
| 552 | But remember that fetch_xfpregs can fail, and return zero. */ |
| 553 | if (regno == -1) |
| 554 | { |
| 555 | fetch_regs (tid); |
| 556 | if (fetch_xfpregs (tid)) |
| 557 | return; |
| 558 | fetch_fpregs (tid); |
| 559 | return; |
| 560 | } |
| 561 | |
| 562 | if (GETREGS_SUPPLIES (regno)) |
| 563 | { |
| 564 | fetch_regs (tid); |
| 565 | return; |
| 566 | } |
| 567 | |
| 568 | if (GETXFPREGS_SUPPLIES (regno)) |
| 569 | { |
| 570 | if (fetch_xfpregs (tid)) |
| 571 | return; |
| 572 | |
| 573 | /* Either our processor or our kernel doesn't support the SSE |
| 574 | registers, so read the FP registers in the traditional way, |
| 575 | and fill the SSE registers with dummy values. It would be |
| 576 | more graceful to handle differences in the register set using |
| 577 | gdbarch. Until then, this will at least make things work |
| 578 | plausibly. */ |
| 579 | fetch_fpregs (tid); |
| 580 | dummy_sse_values (); |
| 581 | return; |
| 582 | } |
| 583 | |
| 584 | internal_error ("i386-linux-nat.c (fetch_inferior_registers): " |
| 585 | "got request for bad register number %d", regno); |
| 586 | } |
| 587 | |
| 588 | |
| 589 | /* Store our register values back into the inferior. |
| 590 | If REGNO is -1, do this for all registers. |
| 591 | Otherwise, REGNO specifies which register, which |
| 592 | then determines whether we store all ordinary |
| 593 | registers or all of the floating point registers. */ |
| 594 | |
| 595 | void |
| 596 | store_inferior_registers (regno) |
| 597 | int regno; |
| 598 | { |
| 599 | /* linux lwp id's are process id's */ |
| 600 | int tid; |
| 601 | |
| 602 | if ((tid = TIDGET (inferior_pid)) == 0) |
| 603 | tid = inferior_pid; /* not a threaded program */ |
| 604 | |
| 605 | /* Use the xfpregs requests whenever possible, since they transfer |
| 606 | more registers in one system call. But remember that |
| 607 | store_xfpregs can fail, and return zero. */ |
| 608 | if (regno == -1) |
| 609 | { |
| 610 | store_regs (tid); |
| 611 | if (store_xfpregs (tid)) |
| 612 | return; |
| 613 | store_fpregs (tid); |
| 614 | return; |
| 615 | } |
| 616 | |
| 617 | if (GETREGS_SUPPLIES (regno)) |
| 618 | { |
| 619 | store_regs (tid); |
| 620 | return; |
| 621 | } |
| 622 | |
| 623 | if (GETXFPREGS_SUPPLIES (regno)) |
| 624 | { |
| 625 | if (store_xfpregs (tid)) |
| 626 | return; |
| 627 | |
| 628 | /* Either our processor or our kernel doesn't support the SSE |
| 629 | registers, so just write the FP registers in the traditional way. */ |
| 630 | store_fpregs (tid); |
| 631 | return; |
| 632 | } |
| 633 | |
| 634 | internal_error ("i386-linux-nat.c (store_inferior_registers): " |
| 635 | "got request to store bad register number %d", regno); |
| 636 | } |
| 637 | |
| 638 | |
| 639 | \f |
| 640 | /* Interpreting register set info found in core files. */ |
| 641 | |
| 642 | /* Provide registers to GDB from a core file. |
| 643 | |
| 644 | (We can't use the generic version of this function in |
| 645 | core-regset.c, because Linux has *three* different kinds of |
| 646 | register set notes. core-regset.c would have to call |
| 647 | supply_xfpregset, which most platforms don't have.) |
| 648 | |
| 649 | CORE_REG_SECT points to an array of bytes, which are the contents |
| 650 | of a `note' from a core file which BFD thinks might contain |
| 651 | register contents. CORE_REG_SIZE is its size. |
| 652 | |
| 653 | WHICH says which register set corelow suspects this is: |
| 654 | 0 --- the general register set, in gregset format |
| 655 | 2 --- the floating-point register set, in fpregset format |
| 656 | 3 --- the extended floating-point register set, in struct |
| 657 | user_xfpregs_struct format |
| 658 | |
| 659 | DUMMY isn't used on Linux. */ |
| 660 | static void |
| 661 | i386_linux_fetch_core_registers (char *core_reg_sect, |
| 662 | unsigned core_reg_size, |
| 663 | int which, |
| 664 | CORE_ADDR dummy) |
| 665 | { |
| 666 | gregset_t gregset; |
| 667 | fpregset_t fpregset; |
| 668 | |
| 669 | switch (which) |
| 670 | { |
| 671 | case 0: |
| 672 | if (core_reg_size != sizeof (gregset)) |
| 673 | warning ("wrong size gregset struct in core file"); |
| 674 | else |
| 675 | { |
| 676 | memcpy (&gregset, core_reg_sect, sizeof (gregset)); |
| 677 | supply_gregset (&gregset); |
| 678 | } |
| 679 | break; |
| 680 | |
| 681 | case 2: |
| 682 | if (core_reg_size != sizeof (fpregset)) |
| 683 | warning ("wrong size fpregset struct in core file"); |
| 684 | else |
| 685 | { |
| 686 | memcpy (&fpregset, core_reg_sect, sizeof (fpregset)); |
| 687 | supply_fpregset (&fpregset); |
| 688 | } |
| 689 | break; |
| 690 | |
| 691 | #ifdef HAVE_PTRACE_GETXFPREGS |
| 692 | { |
| 693 | struct user_xfpregs_struct xfpregset; |
| 694 | case 3: |
| 695 | if (core_reg_size != sizeof (struct user_xfpregs_struct)) |
| 696 | warning ("wrong size user_xfpregs_struct in core file"); |
| 697 | else |
| 698 | { |
| 699 | memcpy (&xfpregset, core_reg_sect, sizeof (xfpregset)); |
| 700 | supply_xfpregset (&xfpregset); |
| 701 | } |
| 702 | break; |
| 703 | } |
| 704 | #endif |
| 705 | |
| 706 | default: |
| 707 | /* We've covered all the kinds of registers we know about here, |
| 708 | so this must be something we wouldn't know what to do with |
| 709 | anyway. Just ignore it. */ |
| 710 | break; |
| 711 | } |
| 712 | } |
| 713 | |
| 714 | |
| 715 | static struct core_fns i386_linux_nat_core_fns = |
| 716 | { |
| 717 | bfd_target_elf_flavour, /* core_flavour */ |
| 718 | default_check_format, /* check_format */ |
| 719 | default_core_sniffer, /* core_sniffer */ |
| 720 | i386_linux_fetch_core_registers, /* core_read_registers */ |
| 721 | NULL /* next */ |
| 722 | }; |
| 723 | |
| 724 | \f |
| 725 | /* Calling functions in shared libraries. */ |
| 726 | |
| 727 | /* Find the minimal symbol named NAME, and return both the minsym |
| 728 | struct and its objfile. This probably ought to be in minsym.c, but |
| 729 | everything there is trying to deal with things like C++ and |
| 730 | SOFUN_ADDRESS_MAYBE_TURQUOISE, ... Since this is so simple, it may |
| 731 | be considered too special-purpose for general consumption. */ |
| 732 | |
| 733 | static struct minimal_symbol * |
| 734 | find_minsym_and_objfile (char *name, struct objfile **objfile_p) |
| 735 | { |
| 736 | struct objfile *objfile; |
| 737 | |
| 738 | ALL_OBJFILES (objfile) |
| 739 | { |
| 740 | struct minimal_symbol *msym; |
| 741 | |
| 742 | ALL_OBJFILE_MSYMBOLS (objfile, msym) |
| 743 | { |
| 744 | if (SYMBOL_NAME (msym) |
| 745 | && STREQ (SYMBOL_NAME (msym), name)) |
| 746 | { |
| 747 | *objfile_p = objfile; |
| 748 | return msym; |
| 749 | } |
| 750 | } |
| 751 | } |
| 752 | |
| 753 | return 0; |
| 754 | } |
| 755 | |
| 756 | |
| 757 | static CORE_ADDR |
| 758 | skip_hurd_resolver (CORE_ADDR pc) |
| 759 | { |
| 760 | /* The HURD dynamic linker is part of the GNU C library, so many |
| 761 | GNU/Linux distributions use it. (All ELF versions, as far as I |
| 762 | know.) An unresolved PLT entry points to "_dl_runtime_resolve", |
| 763 | which calls "fixup" to patch the PLT, and then passes control to |
| 764 | the function. |
| 765 | |
| 766 | We look for the symbol `_dl_runtime_resolve', and find `fixup' in |
| 767 | the same objfile. If we are at the entry point of `fixup', then |
| 768 | we set a breakpoint at the return address (at the top of the |
| 769 | stack), and continue. |
| 770 | |
| 771 | It's kind of gross to do all these checks every time we're |
| 772 | called, since they don't change once the executable has gotten |
| 773 | started. But this is only a temporary hack --- upcoming versions |
| 774 | of Linux will provide a portable, efficient interface for |
| 775 | debugging programs that use shared libraries. */ |
| 776 | |
| 777 | struct objfile *objfile; |
| 778 | struct minimal_symbol *resolver |
| 779 | = find_minsym_and_objfile ("_dl_runtime_resolve", &objfile); |
| 780 | |
| 781 | if (resolver) |
| 782 | { |
| 783 | struct minimal_symbol *fixup |
| 784 | = lookup_minimal_symbol ("fixup", 0, objfile); |
| 785 | |
| 786 | if (fixup && SYMBOL_VALUE_ADDRESS (fixup) == pc) |
| 787 | return (SAVED_PC_AFTER_CALL (get_current_frame ())); |
| 788 | } |
| 789 | |
| 790 | return 0; |
| 791 | } |
| 792 | |
| 793 | |
| 794 | /* See the comments for SKIP_SOLIB_RESOLVER at the top of infrun.c. |
| 795 | This function: |
| 796 | 1) decides whether a PLT has sent us into the linker to resolve |
| 797 | a function reference, and |
| 798 | 2) if so, tells us where to set a temporary breakpoint that will |
| 799 | trigger when the dynamic linker is done. */ |
| 800 | |
| 801 | CORE_ADDR |
| 802 | i386_linux_skip_solib_resolver (CORE_ADDR pc) |
| 803 | { |
| 804 | CORE_ADDR result; |
| 805 | |
| 806 | /* Plug in functions for other kinds of resolvers here. */ |
| 807 | result = skip_hurd_resolver (pc); |
| 808 | if (result) |
| 809 | return result; |
| 810 | |
| 811 | return 0; |
| 812 | } |
| 813 | |
| 814 | |
| 815 | \f |
| 816 | /* Module initialization. */ |
| 817 | |
| 818 | void |
| 819 | _initialize_i386_linux_nat () |
| 820 | { |
| 821 | add_core_fns (&i386_linux_nat_core_fns); |
| 822 | } |