gdb/mips-linux-tdep.c

   1 /* Target-dependent code for GNU/Linux on MIPS processors.
   2
   3    Copyright 2001, 2002 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "gdbcore.h"
  24 #include "target.h"
  25 #include "solib-svr4.h"
  26 #include "osabi.h"
  27 #include "mips-tdep.h"
  28 #include "gdb_string.h"
  29 #include "gdb_assert.h"
  30
  31 /* Copied from <asm/elf.h>.  */
  32 #define ELF_NGREG       45
  33 #define ELF_NFPREG      33
  34
  35 typedef unsigned char elf_greg_t[4];
  36 typedef elf_greg_t elf_gregset_t[ELF_NGREG];
  37
  38 typedef unsigned char elf_fpreg_t[8];
  39 typedef elf_fpreg_t elf_fpregset_t[ELF_NFPREG];
  40
  41 /* 0 - 31 are integer registers, 32 - 63 are fp registers.  */
  42 #define FPR_BASE        32
  43 #define PC              64
  44 #define CAUSE           65
  45 #define BADVADDR        66
  46 #define MMHI            67
  47 #define MMLO            68
  48 #define FPC_CSR         69
  49 #define FPC_EIR         70
  50
  51 #define EF_REG0                 6
  52 #define EF_REG31                37
  53 #define EF_LO                   38
  54 #define EF_HI                   39
  55 #define EF_CP0_EPC              40
  56 #define EF_CP0_BADVADDR         41
  57 #define EF_CP0_STATUS           42
  58 #define EF_CP0_CAUSE            43
  59
  60 #define EF_SIZE                 180
  61
  62 /* Figure out where the longjmp will land.
  63    We expect the first arg to be a pointer to the jmp_buf structure from
  64    which we extract the pc (MIPS_LINUX_JB_PC) that we will land at.  The pc
  65    is copied into PC.  This routine returns 1 on success.  */
  66
  67 #define MIPS_LINUX_JB_ELEMENT_SIZE 4
  68 #define MIPS_LINUX_JB_PC 0
  69
  70 static int
  71 mips_linux_get_longjmp_target (CORE_ADDR *pc)
  72 {
  73   CORE_ADDR jb_addr;
  74   char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT];
  75
  76   jb_addr = read_register (A0_REGNUM);
  77
  78   if (target_read_memory (jb_addr
  79                           + MIPS_LINUX_JB_PC * MIPS_LINUX_JB_ELEMENT_SIZE,
  80                           buf, TARGET_PTR_BIT / TARGET_CHAR_BIT))
  81     return 0;
  82
  83   *pc = extract_unsigned_integer (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
  84
  85   return 1;
  86 }
  87
  88 /* Transform the bits comprising a 32-bit register to the right size
  89    for supply_register().  This is needed when mips_regsize() is 8.  */
  90
  91 static void
  92 supply_32bit_reg (int regnum, const void *addr)
  93 {
  94   char buf[MAX_REGISTER_SIZE];
  95   store_signed_integer (buf, DEPRECATED_REGISTER_RAW_SIZE (regnum),
  96                         extract_signed_integer (addr, 4));
  97   supply_register (regnum, buf);
  98 }
  99
 100 /* Unpack an elf_gregset_t into GDB's register cache.  */
 101
 102 void
 103 supply_gregset (elf_gregset_t *gregsetp)
 104 {
 105   int regi;
 106   elf_greg_t *regp = *gregsetp;
 107   char zerobuf[MAX_REGISTER_SIZE];
 108
 109   memset (zerobuf, 0, MAX_REGISTER_SIZE);
 110
 111   for (regi = EF_REG0; regi <= EF_REG31; regi++)
 112     supply_32bit_reg ((regi - EF_REG0), (char *)(regp + regi));
 113
 114   supply_32bit_reg (LO_REGNUM, (char *)(regp + EF_LO));
 115   supply_32bit_reg (HI_REGNUM, (char *)(regp + EF_HI));
 116
 117   supply_32bit_reg (PC_REGNUM, (char *)(regp + EF_CP0_EPC));
 118   supply_32bit_reg (BADVADDR_REGNUM, (char *)(regp + EF_CP0_BADVADDR));
 119   supply_32bit_reg (PS_REGNUM, (char *)(regp + EF_CP0_STATUS));
 120   supply_32bit_reg (CAUSE_REGNUM, (char *)(regp + EF_CP0_CAUSE));
 121
 122   /* Fill inaccessible registers with zero.  */
 123   supply_register (UNUSED_REGNUM, zerobuf);
 124   for (regi = FIRST_EMBED_REGNUM; regi < LAST_EMBED_REGNUM; regi++)
 125     supply_register (regi, zerobuf);
 126 }
 127
 128 /* Pack our registers (or one register) into an elf_gregset_t.  */
 129
 130 void
 131 fill_gregset (elf_gregset_t *gregsetp, int regno)
 132 {
 133   int regaddr, regi;
 134   elf_greg_t *regp = *gregsetp;
 135   void *dst;
 136
 137   if (regno == -1)
 138     {
 139       memset (regp, 0, sizeof (elf_gregset_t));
 140       for (regi = 0; regi < 32; regi++)
 141         fill_gregset (gregsetp, regi);
 142       fill_gregset (gregsetp, LO_REGNUM);
 143       fill_gregset (gregsetp, HI_REGNUM);
 144       fill_gregset (gregsetp, PC_REGNUM);
 145       fill_gregset (gregsetp, BADVADDR_REGNUM);
 146       fill_gregset (gregsetp, PS_REGNUM);
 147       fill_gregset (gregsetp, CAUSE_REGNUM);
 148
 149       return;
 150    }
 151
 152   if (regno < 32)
 153     {
 154       dst = regp + regno + EF_REG0;
 155       regcache_collect (regno, dst);
 156       return;
 157     }
 158
 159   regaddr = -1;
 160   switch (regno)
 161     {
 162       case LO_REGNUM:
 163         regaddr = EF_LO;
 164         break;
 165       case HI_REGNUM:
 166         regaddr = EF_HI;
 167         break;
 168       case PC_REGNUM:
 169         regaddr = EF_CP0_EPC;
 170         break;
 171       case BADVADDR_REGNUM:
 172         regaddr = EF_CP0_BADVADDR;
 173         break;
 174       case PS_REGNUM:
 175         regaddr = EF_CP0_STATUS;
 176         break;
 177       case CAUSE_REGNUM:
 178         regaddr = EF_CP0_CAUSE;
 179         break;
 180     }
 181
 182   if (regaddr != -1)
 183     {
 184       dst = regp + regaddr;
 185       regcache_collect (regno, dst);
 186     }
 187 }
 188
 189 /* Likewise, unpack an elf_fpregset_t.  */
 190
 191 void
 192 supply_fpregset (elf_fpregset_t *fpregsetp)
 193 {
 194   int regi;
 195   char zerobuf[MAX_REGISTER_SIZE];
 196
 197   memset (zerobuf, 0, MAX_REGISTER_SIZE);
 198
 199   for (regi = 0; regi < 32; regi++)
 200     supply_register (FP0_REGNUM + regi,
 201                      (char *)(*fpregsetp + regi));
 202
 203   supply_register (FCRCS_REGNUM, (char *)(*fpregsetp + 32));
 204
 205   /* FIXME: how can we supply FCRIR_REGNUM?  The ABI doesn't tell us. */
 206   supply_register (FCRIR_REGNUM, zerobuf);
 207 }
 208
 209 /* Likewise, pack one or all floating point registers into an
 210    elf_fpregset_t.  */
 211
 212 void
 213 fill_fpregset (elf_fpregset_t *fpregsetp, int regno)
 214 {
 215   char *from, *to;
 216
 217   if ((regno >= FP0_REGNUM) && (regno < FP0_REGNUM + 32))
 218     {
 219       from = (char *) &deprecated_registers[DEPRECATED_REGISTER_BYTE (regno)];
 220       to = (char *) (*fpregsetp + regno - FP0_REGNUM);
 221       memcpy (to, from, DEPRECATED_REGISTER_RAW_SIZE (regno - FP0_REGNUM));
 222     }
 223   else if (regno == FCRCS_REGNUM)
 224     {
 225       from = (char *) &deprecated_registers[DEPRECATED_REGISTER_BYTE (regno)];
 226       to = (char *) (*fpregsetp + 32);
 227       memcpy (to, from, DEPRECATED_REGISTER_RAW_SIZE (regno));
 228     }
 229   else if (regno == -1)
 230     {
 231       int regi;
 232
 233       for (regi = 0; regi < 32; regi++)
 234         fill_fpregset (fpregsetp, FP0_REGNUM + regi);
 235       fill_fpregset(fpregsetp, FCRCS_REGNUM);
 236     }
 237 }
 238
 239 /* Map gdb internal register number to ptrace ``address''.
 240    These ``addresses'' are normally defined in <asm/ptrace.h>.  */
 241
 242 static CORE_ADDR
 243 mips_linux_register_addr (int regno, CORE_ADDR blockend)
 244 {
 245   int regaddr;
 246
 247   if (regno < 0 || regno >= NUM_REGS)
 248     error ("Bogon register number %d.", regno);
 249
 250   if (regno < 32)
 251     regaddr = regno;
 252   else if ((regno >= FP0_REGNUM) && (regno < FP0_REGNUM + 32))
 253     regaddr = FPR_BASE + (regno - FP0_REGNUM);
 254   else if (regno == PC_REGNUM)
 255     regaddr = PC;
 256   else if (regno == CAUSE_REGNUM)
 257     regaddr = CAUSE;
 258   else if (regno == BADVADDR_REGNUM)
 259     regaddr = BADVADDR;
 260   else if (regno == LO_REGNUM)
 261     regaddr = MMLO;
 262   else if (regno == HI_REGNUM)
 263     regaddr = MMHI;
 264   else if (regno == FCRCS_REGNUM)
 265     regaddr = FPC_CSR;
 266   else if (regno == FCRIR_REGNUM)
 267     regaddr = FPC_EIR;
 268   else
 269     error ("Unknowable register number %d.", regno);
 270
 271   return regaddr;
 272 }
 273
 274
 275 /* Fetch (and possibly build) an appropriate link_map_offsets
 276    structure for native GNU/Linux MIPS targets using the struct offsets
 277    defined in link.h (but without actual reference to that file).
 278
 279    This makes it possible to access GNU/Linux MIPS shared libraries from a
 280    GDB that was built on a different host platform (for cross debugging).  */
 281
 282 static struct link_map_offsets *
 283 mips_linux_svr4_fetch_link_map_offsets (void)
 284 {
 285   static struct link_map_offsets lmo;
 286   static struct link_map_offsets *lmp = NULL;
 287
 288   if (lmp == NULL)
 289     {
 290       lmp = &lmo;
 291
 292       lmo.r_debug_size = 8;     /* The actual size is 20 bytes, but
 293                                    this is all we need.  */
 294       lmo.r_map_offset = 4;
 295       lmo.r_map_size   = 4;
 296
 297       lmo.link_map_size = 20;
 298
 299       lmo.l_addr_offset = 0;
 300       lmo.l_addr_size   = 4;
 301
 302       lmo.l_name_offset = 4;
 303       lmo.l_name_size   = 4;
 304
 305       lmo.l_next_offset = 12;
 306       lmo.l_next_size   = 4;
 307
 308       lmo.l_prev_offset = 16;
 309       lmo.l_prev_size   = 4;
 310     }
 311
 312   return lmp;
 313 }
 314
 315 /* Support for 64-bit ABIs.  */
 316
 317 /* Copied from <asm/elf.h>.  */
 318 #define MIPS64_ELF_NGREG       45
 319 #define MIPS64_ELF_NFPREG      33
 320
 321 typedef unsigned char mips64_elf_greg_t[8];
 322 typedef mips64_elf_greg_t mips64_elf_gregset_t[MIPS64_ELF_NGREG];
 323
 324 typedef unsigned char mips64_elf_fpreg_t[8];
 325 typedef mips64_elf_fpreg_t mips64_elf_fpregset_t[MIPS64_ELF_NFPREG];
 326
 327 /* 0 - 31 are integer registers, 32 - 63 are fp registers.  */
 328 #define MIPS64_FPR_BASE                 32
 329 #define MIPS64_PC                       64
 330 #define MIPS64_CAUSE                    65
 331 #define MIPS64_BADVADDR                 66
 332 #define MIPS64_MMHI                     67
 333 #define MIPS64_MMLO                     68
 334 #define MIPS64_FPC_CSR                  69
 335 #define MIPS64_FPC_EIR                  70
 336
 337 #define MIPS64_EF_REG0                   0
 338 #define MIPS64_EF_REG31                 31
 339 #define MIPS64_EF_LO                    32
 340 #define MIPS64_EF_HI                    33
 341 #define MIPS64_EF_CP0_EPC               34
 342 #define MIPS64_EF_CP0_BADVADDR          35
 343 #define MIPS64_EF_CP0_STATUS            36
 344 #define MIPS64_EF_CP0_CAUSE             37
 345
 346 #define MIPS64_EF_SIZE                  304
 347
 348 /* Figure out where the longjmp will land.
 349    We expect the first arg to be a pointer to the jmp_buf structure from
 350    which we extract the pc (MIPS_LINUX_JB_PC) that we will land at.  The pc
 351    is copied into PC.  This routine returns 1 on success.  */
 352
 353 /* Details about jmp_buf.  */
 354
 355 #define MIPS64_LINUX_JB_PC 0
 356
 357 static int
 358 mips64_linux_get_longjmp_target (CORE_ADDR *pc)
 359 {
 360   CORE_ADDR jb_addr;
 361   void *buf = alloca (TARGET_PTR_BIT / TARGET_CHAR_BIT);
 362   int element_size = TARGET_PTR_BIT == 32 ? 4 : 8;
 363
 364   jb_addr = read_register (A0_REGNUM);
 365
 366   if (target_read_memory (jb_addr + MIPS64_LINUX_JB_PC * element_size,
 367                           buf, TARGET_PTR_BIT / TARGET_CHAR_BIT))
 368     return 0;
 369
 370   *pc = extract_unsigned_integer (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
 371
 372   return 1;
 373 }
 374
 375 /* Unpack an elf_gregset_t into GDB's register cache.  */
 376
 377 static void
 378 mips64_supply_gregset (mips64_elf_gregset_t *gregsetp)
 379 {
 380   int regi;
 381   mips64_elf_greg_t *regp = *gregsetp;
 382   char zerobuf[MAX_REGISTER_SIZE];
 383
 384   memset (zerobuf, 0, MAX_REGISTER_SIZE);
 385
 386   for (regi = MIPS64_EF_REG0; regi <= MIPS64_EF_REG31; regi++)
 387     supply_register ((regi - MIPS64_EF_REG0), (char *)(regp + regi));
 388
 389   supply_register (LO_REGNUM, (char *)(regp + MIPS64_EF_LO));
 390   supply_register (HI_REGNUM, (char *)(regp + MIPS64_EF_HI));
 391
 392   supply_register (PC_REGNUM, (char *)(regp + MIPS64_EF_CP0_EPC));
 393   supply_register (BADVADDR_REGNUM, (char *)(regp + MIPS64_EF_CP0_BADVADDR));
 394   supply_register (PS_REGNUM, (char *)(regp + MIPS64_EF_CP0_STATUS));
 395   supply_register (CAUSE_REGNUM, (char *)(regp + MIPS64_EF_CP0_CAUSE));
 396
 397   /* Fill inaccessible registers with zero.  */
 398   supply_register (UNUSED_REGNUM, zerobuf);
 399   for (regi = FIRST_EMBED_REGNUM; regi < LAST_EMBED_REGNUM; regi++)
 400     supply_register (regi, zerobuf);
 401 }
 402
 403 /* Pack our registers (or one register) into an elf_gregset_t.  */
 404
 405 static void
 406 mips64_fill_gregset (mips64_elf_gregset_t *gregsetp, int regno)
 407 {
 408   int regaddr, regi;
 409   mips64_elf_greg_t *regp = *gregsetp;
 410   void *src, *dst;
 411
 412   if (regno == -1)
 413     {
 414       memset (regp, 0, sizeof (mips64_elf_gregset_t));
 415       for (regi = 0; regi < 32; regi++)
 416         mips64_fill_gregset (gregsetp, regi);
 417       mips64_fill_gregset (gregsetp, LO_REGNUM);
 418       mips64_fill_gregset (gregsetp, HI_REGNUM);
 419       mips64_fill_gregset (gregsetp, PC_REGNUM);
 420       mips64_fill_gregset (gregsetp, BADVADDR_REGNUM);
 421       mips64_fill_gregset (gregsetp, PS_REGNUM);
 422       mips64_fill_gregset (gregsetp, CAUSE_REGNUM);
 423
 424       return;
 425    }
 426
 427   if (regno < 32)
 428     {
 429       dst = regp + regno + MIPS64_EF_REG0;
 430       regcache_collect (regno, dst);
 431       return;
 432     }
 433
 434   regaddr = -1;
 435   switch (regno)
 436     {
 437       case LO_REGNUM:
 438         regaddr = MIPS64_EF_LO;
 439         break;
 440       case HI_REGNUM:
 441         regaddr = MIPS64_EF_HI;
 442         break;
 443       case PC_REGNUM:
 444         regaddr = MIPS64_EF_CP0_EPC;
 445         break;
 446       case BADVADDR_REGNUM:
 447         regaddr = MIPS64_EF_CP0_BADVADDR;
 448         break;
 449       case PS_REGNUM:
 450         regaddr = MIPS64_EF_CP0_STATUS;
 451         break;
 452       case CAUSE_REGNUM:
 453         regaddr = MIPS64_EF_CP0_CAUSE;
 454         break;
 455     }
 456
 457   if (regaddr != -1)
 458     {
 459       dst = regp + regaddr;
 460       regcache_collect (regno, dst);
 461     }
 462 }
 463
 464 /* Likewise, unpack an elf_fpregset_t.  */
 465
 466 static void
 467 mips64_supply_fpregset (mips64_elf_fpregset_t *fpregsetp)
 468 {
 469   int regi;
 470   char zerobuf[MAX_REGISTER_SIZE];
 471
 472   memset (zerobuf, 0, MAX_REGISTER_SIZE);
 473
 474   for (regi = 0; regi < 32; regi++)
 475     supply_register (FP0_REGNUM + regi,
 476                      (char *)(*fpregsetp + regi));
 477
 478   supply_register (FCRCS_REGNUM, (char *)(*fpregsetp + 32));
 479
 480   /* FIXME: how can we supply FCRIR_REGNUM?  The ABI doesn't tell us. */
 481   supply_register (FCRIR_REGNUM, zerobuf);
 482 }
 483
 484 /* Likewise, pack one or all floating point registers into an
 485    elf_fpregset_t.  */
 486
 487 static void
 488 mips64_fill_fpregset (mips64_elf_fpregset_t *fpregsetp, int regno)
 489 {
 490   char *from, *to;
 491
 492   if ((regno >= FP0_REGNUM) && (regno < FP0_REGNUM + 32))
 493     {
 494       from = (char *) &deprecated_registers[DEPRECATED_REGISTER_BYTE (regno)];
 495       to = (char *) (*fpregsetp + regno - FP0_REGNUM);
 496       memcpy (to, from, DEPRECATED_REGISTER_RAW_SIZE (regno - FP0_REGNUM));
 497     }
 498   else if (regno == FCRCS_REGNUM)
 499     {
 500       from = (char *) &deprecated_registers[DEPRECATED_REGISTER_BYTE (regno)];
 501       to = (char *) (*fpregsetp + 32);
 502       memcpy (to, from, DEPRECATED_REGISTER_RAW_SIZE (regno));
 503     }
 504   else if (regno == -1)
 505     {
 506       int regi;
 507
 508       for (regi = 0; regi < 32; regi++)
 509         mips64_fill_fpregset (fpregsetp, FP0_REGNUM + regi);
 510       mips64_fill_fpregset(fpregsetp, FCRCS_REGNUM);
 511     }
 512 }
 513
 514
 515 /* Map gdb internal register number to ptrace ``address''.
 516    These ``addresses'' are normally defined in <asm/ptrace.h>.  */
 517
 518 static CORE_ADDR
 519 mips64_linux_register_addr (int regno, CORE_ADDR blockend)
 520 {
 521   int regaddr;
 522
 523   if (regno < 0 || regno >= NUM_REGS)
 524     error ("Bogon register number %d.", regno);
 525
 526   if (regno < 32)
 527     regaddr = regno;
 528   else if ((regno >= FP0_REGNUM) && (regno < FP0_REGNUM + 32))
 529     regaddr = MIPS64_FPR_BASE + (regno - FP0_REGNUM);
 530   else if (regno == PC_REGNUM)
 531     regaddr = MIPS64_PC;
 532   else if (regno == CAUSE_REGNUM)
 533     regaddr = MIPS64_CAUSE;
 534   else if (regno == BADVADDR_REGNUM)
 535     regaddr = MIPS64_BADVADDR;
 536   else if (regno == LO_REGNUM)
 537     regaddr = MIPS64_MMLO;
 538   else if (regno == HI_REGNUM)
 539     regaddr = MIPS64_MMHI;
 540   else if (regno == FCRCS_REGNUM)
 541     regaddr = MIPS64_FPC_CSR;
 542   else if (regno == FCRIR_REGNUM)
 543     regaddr = MIPS64_FPC_EIR;
 544   else
 545     error ("Unknowable register number %d.", regno);
 546
 547   return regaddr;
 548 }
 549
 550 /*  Use a local version of this function to get the correct types for
 551     regsets, until multi-arch core support is ready.  */
 552
 553 static void
 554 fetch_core_registers (char *core_reg_sect, unsigned core_reg_size,
 555                       int which, CORE_ADDR reg_addr)
 556 {
 557   elf_gregset_t gregset;
 558   elf_fpregset_t fpregset;
 559   mips64_elf_gregset_t gregset64;
 560   mips64_elf_fpregset_t fpregset64;
 561
 562   if (which == 0)
 563     {
 564       if (core_reg_size == sizeof (gregset))
 565         {
 566           memcpy ((char *) &gregset, core_reg_sect, sizeof (gregset));
 567           supply_gregset (&gregset);
 568         }
 569       else if (core_reg_size == sizeof (gregset64))
 570         {
 571           memcpy ((char *) &gregset64, core_reg_sect, sizeof (gregset64));
 572           mips64_supply_gregset (&gregset64);
 573         }
 574       else
 575         {
 576           warning ("wrong size gregset struct in core file");
 577         }
 578     }
 579   else if (which == 2)
 580     {
 581       if (core_reg_size == sizeof (fpregset))
 582         {
 583           memcpy ((char *) &fpregset, core_reg_sect, sizeof (fpregset));
 584           supply_fpregset (&fpregset);
 585         }
 586       else if (core_reg_size == sizeof (fpregset64))
 587         {
 588           memcpy ((char *) &fpregset64, core_reg_sect, sizeof (fpregset64));
 589           mips64_supply_fpregset (&fpregset64);
 590         }
 591       else
 592         {
 593           warning ("wrong size fpregset struct in core file");
 594         }
 595     }
 596 }
 597
 598 /* Register that we are able to handle ELF file formats using standard
 599    procfs "regset" structures.  */
 600
 601 static struct core_fns regset_core_fns =
 602 {
 603   bfd_target_elf_flavour,               /* core_flavour */
 604   default_check_format,                 /* check_format */
 605   default_core_sniffer,                 /* core_sniffer */
 606   fetch_core_registers,                 /* core_read_registers */
 607   NULL                                  /* next */
 608 };
 609
 610 /* Fetch (and possibly build) an appropriate link_map_offsets
 611    structure for native GNU/Linux MIPS targets using the struct offsets
 612    defined in link.h (but without actual reference to that file).
 613
 614    This makes it possible to access GNU/Linux MIPS shared libraries from a
 615    GDB that was built on a different host platform (for cross debugging).  */
 616
 617 static struct link_map_offsets *
 618 mips64_linux_svr4_fetch_link_map_offsets (void)
 619 {
 620   static struct link_map_offsets lmo;
 621   static struct link_map_offsets *lmp = NULL;
 622
 623   if (lmp == NULL)
 624     {
 625       lmp = &lmo;
 626
 627       lmo.r_debug_size = 16;    /* The actual size is 40 bytes, but
 628                                    this is all we need.  */
 629       lmo.r_map_offset = 8;
 630       lmo.r_map_size   = 8;
 631
 632       lmo.link_map_size = 40;
 633
 634       lmo.l_addr_offset = 0;
 635       lmo.l_addr_size   = 8;
 636
 637       lmo.l_name_offset = 8;
 638       lmo.l_name_size   = 8;
 639
 640       lmo.l_next_offset = 24;
 641       lmo.l_next_size   = 8;
 642
 643       lmo.l_prev_offset = 32;
 644       lmo.l_prev_size   = 8;
 645     }
 646
 647   return lmp;
 648 }
 649
 650 /* Handle for obtaining pointer to the current register_addr() function
 651    for a given architecture.  */
 652 static struct gdbarch_data *register_addr_data;
 653
 654 CORE_ADDR
 655 register_addr (int regno, CORE_ADDR blockend)
 656 {
 657   CORE_ADDR (*register_addr_ptr) (int, CORE_ADDR) =
 658     gdbarch_data (current_gdbarch, register_addr_data);
 659
 660   gdb_assert (register_addr_ptr != 0);
 661
 662   return register_addr_ptr (regno, blockend);
 663 }
 664
 665 static void
 666 set_mips_linux_register_addr (struct gdbarch *gdbarch,
 667                               CORE_ADDR (*register_addr_ptr) (int, CORE_ADDR))
 668 {
 669   set_gdbarch_data (gdbarch, register_addr_data, register_addr_ptr);
 670 }
 671
 672 static void *
 673 init_register_addr_data (struct gdbarch *gdbarch)
 674 {
 675   return 0;
 676 }
 677
 678 static void
 679 mips_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 680 {
 681   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 682   enum mips_abi abi = mips_abi (gdbarch);
 683
 684   switch (abi)
 685     {
 686       case MIPS_ABI_O32:
 687         set_gdbarch_get_longjmp_target (gdbarch,
 688                                         mips_linux_get_longjmp_target);
 689         set_solib_svr4_fetch_link_map_offsets
 690           (gdbarch, mips_linux_svr4_fetch_link_map_offsets);
 691         set_mips_linux_register_addr (gdbarch, mips_linux_register_addr);
 692         break;
 693       case MIPS_ABI_N32:
 694         set_gdbarch_get_longjmp_target (gdbarch,
 695                                         mips_linux_get_longjmp_target);
 696         set_solib_svr4_fetch_link_map_offsets
 697           (gdbarch, mips_linux_svr4_fetch_link_map_offsets);
 698         set_mips_linux_register_addr (gdbarch, mips64_linux_register_addr);
 699         break;
 700       case MIPS_ABI_N64:
 701         set_gdbarch_get_longjmp_target (gdbarch,
 702                                         mips64_linux_get_longjmp_target);
 703         set_solib_svr4_fetch_link_map_offsets
 704           (gdbarch, mips64_linux_svr4_fetch_link_map_offsets);
 705         set_mips_linux_register_addr (gdbarch, mips64_linux_register_addr);
 706         break;
 707       default:
 708         internal_error (__FILE__, __LINE__, "can't handle ABI");
 709         break;
 710     }
 711 }
 712
 713 void
 714 _initialize_mips_linux_tdep (void)
 715 {
 716   const struct bfd_arch_info *arch_info;
 717
 718   register_addr_data =
 719     register_gdbarch_data (init_register_addr_data);
 720
 721   for (arch_info = bfd_lookup_arch (bfd_arch_mips, 0);
 722        arch_info != NULL;
 723        arch_info = arch_info->next)
 724     {
 725       gdbarch_register_osabi (bfd_arch_mips, arch_info->mach, GDB_OSABI_LINUX,
 726                               mips_linux_init_abi);
 727     }
 728
 729   add_core_fns (&regset_core_fns);
 730 }