gdb/arch-utils.c

   1 /* Dynamic architecture support for GDB, the GNU debugger.
   2    Copyright 1998-1999, Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include "defs.h"
  22
  23 #if GDB_MULTI_ARCH
  24 #include "gdbcmd.h"
  25 #include "inferior.h"           /* enum CALL_DUMMY_LOCATION et.al. */
  26 #else
  27 /* Just include everything in sight so that the every old definition
  28    of macro is visible. */
  29 #include "gdb_string.h"
  30 #include <ctype.h>
  31 #include "symtab.h"
  32 #include "frame.h"
  33 #include "inferior.h"
  34 #include "breakpoint.h"
  35 #include "gdb_wait.h"
  36 #include "gdbcore.h"
  37 #include "gdbcmd.h"
  38 #include "target.h"
  39 #include "gdbthread.h"
  40 #include "annotate.h"
  41 #include "symfile.h"            /* for overlay functions */
  42 #endif
  43
  44 #include "version.h"
  45
  46 #include "floatformat.h"
  47
  48 /* Convenience macro for allocting typesafe memory. */
  49
  50 #ifndef XMALLOC
  51 #define XMALLOC(TYPE) (TYPE*) xmalloc (sizeof (TYPE))
  52 #endif
  53
  54
  55 /* Use the program counter to determine the contents and size
  56    of a breakpoint instruction.  If no target-dependent macro
  57    BREAKPOINT_FROM_PC has been defined to implement this function,
  58    assume that the breakpoint doesn't depend on the PC, and
  59    use the values of the BIG_BREAKPOINT and LITTLE_BREAKPOINT macros.
  60    Return a pointer to a string of bytes that encode a breakpoint
  61    instruction, stores the length of the string to *lenptr,
  62    and optionally adjust the pc to point to the correct memory location
  63    for inserting the breakpoint.  */
  64
  65 unsigned char *
  66 legacy_breakpoint_from_pc (CORE_ADDR * pcptr, int *lenptr)
  67 {
  68   /* {BIG_,LITTLE_}BREAKPOINT is the sequence of bytes we insert for a
  69      breakpoint.  On some machines, breakpoints are handled by the
  70      target environment and we don't have to worry about them here.  */
  71 #ifdef BIG_BREAKPOINT
  72   if (TARGET_BYTE_ORDER == BIG_ENDIAN)
  73     {
  74       static unsigned char big_break_insn[] = BIG_BREAKPOINT;
  75       *lenptr = sizeof (big_break_insn);
  76       return big_break_insn;
  77     }
  78 #endif
  79 #ifdef LITTLE_BREAKPOINT
  80   if (TARGET_BYTE_ORDER != BIG_ENDIAN)
  81     {
  82       static unsigned char little_break_insn[] = LITTLE_BREAKPOINT;
  83       *lenptr = sizeof (little_break_insn);
  84       return little_break_insn;
  85     }
  86 #endif
  87 #ifdef BREAKPOINT
  88   {
  89     static unsigned char break_insn[] = BREAKPOINT;
  90     *lenptr = sizeof (break_insn);
  91     return break_insn;
  92   }
  93 #endif
  94   *lenptr = 0;
  95   return NULL;
  96 }
  97
  98 int
  99 generic_frameless_function_invocation_not (struct frame_info *fi)
 100 {
 101   return 0;
 102 }
 103
 104 int
 105 generic_return_value_on_stack_not (struct type *type)
 106 {
 107   return 0;
 108 }
 109
 110 char *
 111 legacy_register_name (int i)
 112 {
 113 #ifdef REGISTER_NAMES
 114   static char *names[] = REGISTER_NAMES;
 115   if (i < 0 || i >= (sizeof (names) / sizeof (*names)))
 116     return NULL;
 117   else
 118     return names[i];
 119 #else
 120   internal_error ("legacy_register_name: called.");
 121   return NULL;
 122 #endif
 123 }
 124
 125 #if defined (CALL_DUMMY)
 126 LONGEST legacy_call_dummy_words[] = CALL_DUMMY;
 127 #else
 128 LONGEST legacy_call_dummy_words[1];
 129 #endif
 130 int legacy_sizeof_call_dummy_words = sizeof (legacy_call_dummy_words);
 131
 132 void
 133 generic_remote_translate_xfer_address (CORE_ADDR gdb_addr, int gdb_len,
 134                                        CORE_ADDR * rem_addr, int *rem_len)
 135 {
 136   *rem_addr = gdb_addr;
 137   *rem_len = gdb_len;
 138 }
 139
 140 int
 141 generic_prologue_frameless_p (CORE_ADDR ip)
 142 {
 143 #ifdef SKIP_PROLOGUE_FRAMELESS_P
 144   return ip == SKIP_PROLOGUE_FRAMELESS_P (ip);
 145 #else
 146   return ip == SKIP_PROLOGUE (ip);
 147 #endif
 148 }
 149
 150
 151 /* Helper functions for INNER_THAN */
 152
 153 int
 154 core_addr_lessthan (CORE_ADDR lhs, CORE_ADDR rhs)
 155 {
 156   return (lhs < rhs);
 157 }
 158
 159 int
 160 core_addr_greaterthan (CORE_ADDR lhs, CORE_ADDR rhs)
 161 {
 162   return (lhs > rhs);
 163 }
 164
 165
 166 /* Helper functions for TARGET_{FLOAT,DOUBLE}_FORMAT */
 167
 168 const struct floatformat *
 169 default_float_format (struct gdbarch *gdbarch)
 170 {
 171 #if GDB_MULTI_ARCH
 172   int byte_order = gdbarch_byte_order (gdbarch);
 173 #else
 174   int byte_order = TARGET_BYTE_ORDER;
 175 #endif
 176   switch (byte_order)
 177     {
 178     case BIG_ENDIAN:
 179       return &floatformat_ieee_single_big;
 180     case LITTLE_ENDIAN:
 181       return &floatformat_ieee_single_little;
 182     default:
 183       internal_error ("default_float_format: bad byte order");
 184     }
 185 }
 186
 187
 188 const struct floatformat *
 189 default_double_format (struct gdbarch *gdbarch)
 190 {
 191 #if GDB_MULTI_ARCH
 192   int byte_order = gdbarch_byte_order (gdbarch);
 193 #else
 194   int byte_order = TARGET_BYTE_ORDER;
 195 #endif
 196   switch (byte_order)
 197     {
 198     case BIG_ENDIAN:
 199       return &floatformat_ieee_double_big;
 200     case LITTLE_ENDIAN:
 201       return &floatformat_ieee_double_little;
 202     default:
 203       internal_error ("default_double_format: bad byte order");
 204     }
 205 }
 206
 207 /* Misc helper functions for targets. */
 208
 209 int
 210 frame_num_args_unknown (struct frame_info *fi)
 211 {
 212   return -1;
 213 }
 214
 215
 216 int
 217 generic_register_convertible_not (int num)
 218 {
 219   return 0;
 220 }
 221
 222
 223 /* Functions to manipulate the endianness of the target.  */
 224
 225 #ifdef TARGET_BYTE_ORDER_SELECTABLE
 226 /* compat - Catch old targets that expect a selectable byte-order to
 227    default to BIG_ENDIAN */
 228 #ifndef TARGET_BYTE_ORDER_DEFAULT
 229 #define TARGET_BYTE_ORDER_DEFAULT BIG_ENDIAN
 230 #endif
 231 #endif
 232 #if !TARGET_BYTE_ORDER_SELECTABLE_P
 233 #ifndef TARGET_BYTE_ORDER_DEFAULT
 234 /* compat - Catch old non byte-order selectable targets that do not
 235    define TARGET_BYTE_ORDER_DEFAULT and instead expect
 236    TARGET_BYTE_ORDER to be used as the default.  For targets that
 237    defined neither TARGET_BYTE_ORDER nor TARGET_BYTE_ORDER_DEFAULT the
 238    below will get a strange compiler warning. */
 239 #define TARGET_BYTE_ORDER_DEFAULT TARGET_BYTE_ORDER
 240 #endif
 241 #endif
 242 #ifndef TARGET_BYTE_ORDER_DEFAULT
 243 #define TARGET_BYTE_ORDER_DEFAULT BIG_ENDIAN /* arbitrary */
 244 #endif
 245 /* ``target_byte_order'' is only used when non- multi-arch.
 246    Multi-arch targets obtain the current byte order using
 247    TARGET_BYTE_ORDER which is controlled by gdbarch.*. */
 248 int target_byte_order = TARGET_BYTE_ORDER_DEFAULT;
 249 int target_byte_order_auto = 1;
 250
 251 static const char endian_big[] = "big";
 252 static const char endian_little[] = "little";
 253 static const char endian_auto[] = "auto";
 254 static const char *endian_enum[] =
 255 {
 256   endian_big,
 257   endian_little,
 258   endian_auto,
 259   NULL,
 260 };
 261 static const char *set_endian_string;
 262
 263 /* Called by ``show endian''.  */
 264
 265 static void
 266 show_endian (char *args, int from_tty)
 267 {
 268   if (TARGET_BYTE_ORDER_AUTO)
 269     printf_unfiltered ("The target endianness is set automatically (currently %s endian)\n",
 270                        (TARGET_BYTE_ORDER == BIG_ENDIAN ? "big" : "little"));
 271   else
 272     printf_unfiltered ("The target is assumed to be %s endian\n",
 273                        (TARGET_BYTE_ORDER == BIG_ENDIAN ? "big" : "little"));
 274 }
 275
 276 static void
 277 set_endian (char *ignore_args, int from_tty, struct cmd_list_element *c)
 278 {
 279   if (!TARGET_BYTE_ORDER_SELECTABLE_P)
 280     {
 281       printf_unfiltered ("Byte order is not selectable.");
 282     }
 283   else if (set_endian_string == endian_auto)
 284     {
 285       target_byte_order_auto = 1;
 286     }
 287   else if (set_endian_string == endian_little)
 288     {
 289       target_byte_order_auto = 0;
 290       if (GDB_MULTI_ARCH)
 291         {
 292           struct gdbarch_info info;
 293           memset (&info, 0, sizeof info);
 294           info.byte_order = LITTLE_ENDIAN;
 295           gdbarch_update (info);
 296         }
 297       else
 298         {
 299           target_byte_order = LITTLE_ENDIAN;
 300         }
 301     }
 302   else if (set_endian_string == endian_big)
 303     {
 304       target_byte_order_auto = 0;
 305       if (GDB_MULTI_ARCH)
 306         {
 307           struct gdbarch_info info;
 308           memset (&info, 0, sizeof info);
 309           info.byte_order = BIG_ENDIAN;
 310           gdbarch_update (info);
 311         }
 312       else
 313         {
 314           target_byte_order = BIG_ENDIAN;
 315         }
 316     }
 317   else
 318     internal_error ("set_endian: bad value");
 319   show_endian (NULL, from_tty);
 320 }
 321
 322 /* Set the endianness from a BFD.  */
 323
 324 static void
 325 set_endian_from_file (bfd *abfd)
 326 {
 327   if (GDB_MULTI_ARCH)
 328     internal_error ("set_endian_from_file: not for multi-arch");
 329   if (TARGET_BYTE_ORDER_SELECTABLE_P)
 330     {
 331       int want;
 332
 333       if (bfd_big_endian (abfd))
 334         want = BIG_ENDIAN;
 335       else
 336         want = LITTLE_ENDIAN;
 337       if (TARGET_BYTE_ORDER_AUTO)
 338         target_byte_order = want;
 339       else if (TARGET_BYTE_ORDER != want)
 340         warning ("%s endian file does not match %s endian target.",
 341                  want == BIG_ENDIAN ? "big" : "little",
 342                  TARGET_BYTE_ORDER == BIG_ENDIAN ? "big" : "little");
 343     }
 344   else
 345     {
 346       if (bfd_big_endian (abfd)
 347           ? TARGET_BYTE_ORDER != BIG_ENDIAN
 348           : TARGET_BYTE_ORDER == BIG_ENDIAN)
 349         warning ("%s endian file does not match %s endian target.",
 350                  bfd_big_endian (abfd) ? "big" : "little",
 351                  TARGET_BYTE_ORDER == BIG_ENDIAN ? "big" : "little");
 352     }
 353 }
 354
 355
 356 /* Functions to manipulate the architecture of the target */
 357
 358 enum set_arch { set_arch_auto, set_arch_manual };
 359
 360 int target_architecture_auto = 1;
 361
 362 const char *set_architecture_string;
 363
 364 /* Old way of changing the current architecture. */
 365
 366 extern const struct bfd_arch_info bfd_default_arch_struct;
 367 const struct bfd_arch_info *target_architecture = &bfd_default_arch_struct;
 368 int (*target_architecture_hook) (const struct bfd_arch_info *ap);
 369
 370 static int
 371 arch_ok (const struct bfd_arch_info *arch)
 372 {
 373   if (GDB_MULTI_ARCH)
 374     internal_error ("arch_ok: not multi-arched");
 375   /* Should be performing the more basic check that the binary is
 376      compatible with GDB. */
 377   /* Check with the target that the architecture is valid. */
 378   return (target_architecture_hook == NULL
 379           || target_architecture_hook (arch));
 380 }
 381
 382 static void
 383 set_arch (const struct bfd_arch_info *arch,
 384           enum set_arch type)
 385 {
 386   if (GDB_MULTI_ARCH)
 387     internal_error ("set_arch: not multi-arched");
 388   switch (type)
 389     {
 390     case set_arch_auto:
 391       if (!arch_ok (arch))
 392         warning ("Target may not support %s architecture",
 393                  arch->printable_name);
 394       target_architecture = arch;
 395       break;
 396     case set_arch_manual:
 397       if (!arch_ok (arch))
 398         {
 399           printf_unfiltered ("Target does not support `%s' architecture.\n",
 400                              arch->printable_name);
 401         }
 402       else
 403         {
 404           target_architecture_auto = 0;
 405           target_architecture = arch;
 406         }
 407       break;
 408     }
 409   if (gdbarch_debug)
 410     gdbarch_dump (current_gdbarch, gdb_stdlog);
 411 }
 412
 413 /* Set the architecture from arch/machine (deprecated) */
 414
 415 void
 416 set_architecture_from_arch_mach (enum bfd_architecture arch,
 417                                  unsigned long mach)
 418 {
 419   const struct bfd_arch_info *wanted = bfd_lookup_arch (arch, mach);
 420   if (GDB_MULTI_ARCH)
 421     internal_error ("set_architecture_from_arch_mach: not multi-arched");
 422   if (wanted != NULL)
 423     set_arch (wanted, set_arch_manual);
 424   else
 425     internal_error ("gdbarch: hardwired architecture/machine not reconized");
 426 }
 427
 428 /* Set the architecture from a BFD (deprecated) */
 429
 430 static void
 431 set_architecture_from_file (bfd *abfd)
 432 {
 433   const struct bfd_arch_info *wanted = bfd_get_arch_info (abfd);
 434   if (GDB_MULTI_ARCH)
 435     internal_error ("set_architecture_from_file: not multi-arched");
 436   if (target_architecture_auto)
 437     {
 438       set_arch (wanted, set_arch_auto);
 439     }
 440   else if (wanted != target_architecture)
 441     {
 442       warning ("%s architecture file may be incompatible with %s target.",
 443                wanted->printable_name,
 444                target_architecture->printable_name);
 445     }
 446 }
 447
 448
 449 /* Called if the user enters ``show architecture'' without an
 450    argument. */
 451
 452 static void
 453 show_architecture (char *args, int from_tty)
 454 {
 455   const char *arch;
 456   arch = TARGET_ARCHITECTURE->printable_name;
 457   if (target_architecture_auto)
 458     printf_filtered ("The target architecture is set automatically (currently %s)\n", arch);
 459   else
 460     printf_filtered ("The target architecture is assumed to be %s\n", arch);
 461 }
 462
 463
 464 /* Called if the user enters ``set architecture'' with or without an
 465    argument. */
 466
 467 static void
 468 set_architecture (char *ignore_args, int from_tty, struct cmd_list_element *c)
 469 {
 470   if (strcmp (set_architecture_string, "auto") == 0)
 471     {
 472       target_architecture_auto = 1;
 473     }
 474   else if (GDB_MULTI_ARCH)
 475     {
 476       struct gdbarch_info info;
 477       memset (&info, 0, sizeof info);
 478       info.bfd_arch_info = bfd_scan_arch (set_architecture_string);
 479       if (info.bfd_arch_info == NULL)
 480         internal_error ("set_architecture: bfd_scan_arch failed");
 481       if (gdbarch_update (info))
 482         target_architecture_auto = 0;
 483       else
 484         printf_unfiltered ("Architecture `%s' not reconized.\n",
 485                            set_architecture_string);
 486     }
 487   else
 488     {
 489       const struct bfd_arch_info *arch
 490         = bfd_scan_arch (set_architecture_string);
 491       if (arch == NULL)
 492         internal_error ("set_architecture: bfd_scan_arch failed");
 493       set_arch (arch, set_arch_manual);
 494     }
 495   show_architecture (NULL, from_tty);
 496 }
 497
 498 /* Called if the user enters ``info architecture'' without an argument. */
 499
 500 static void
 501 info_architecture (char *args, int from_tty)
 502 {
 503   printf_filtered ("Available architectures are:\n");
 504   if (GDB_MULTI_ARCH)
 505     {
 506       const char **arches = gdbarch_printable_names ();
 507       const char **arch;
 508       for (arch = arches; *arch != NULL; arch++)
 509         {
 510           printf_filtered (" %s", *arch);
 511         }
 512       free (arches);
 513     }
 514   else
 515     {
 516       enum bfd_architecture a;
 517       for (a = bfd_arch_obscure + 1; a < bfd_arch_last; a++)
 518         {
 519           const struct bfd_arch_info *ap;
 520           for (ap = bfd_lookup_arch (a, 0);
 521                ap != NULL;
 522                ap = ap->next)
 523             {
 524               printf_filtered (" %s", ap->printable_name);
 525               ap = ap->next;
 526             }
 527         }
 528     }
 529   printf_filtered ("\n");
 530 }
 531
 532 /* Set the dynamic target-system-dependant parameters (architecture,
 533    byte-order) using information found in the BFD */
 534
 535 void
 536 set_gdbarch_from_file (bfd *abfd)
 537 {
 538   if (GDB_MULTI_ARCH)
 539     {
 540       struct gdbarch_info info;
 541       memset (&info, 0, sizeof info);
 542       info.abfd = abfd;
 543       gdbarch_update (info);
 544     }
 545   else
 546     {
 547       set_architecture_from_file (abfd);
 548       set_endian_from_file (abfd);
 549     }
 550 }
 551
 552 /* Initialize the current architecture.  Update the ``set
 553    architecture'' command so that it specifies a list of valid
 554    architectures.  */
 555
 556 #ifdef DEFAULT_BFD_ARCH
 557 extern const bfd_arch_info_type DEFAULT_BFD_ARCH;
 558 static const bfd_arch_info_type *default_bfd_arch = &DEFAULT_BFD_ARCH;
 559 #else
 560 static const bfd_arch_info_type *default_bfd_arch;
 561 #endif
 562
 563 #ifdef DEFAULT_BFD_VEC
 564 extern const bfd_target DEFAULT_BFD_VEC;
 565 static const bfd_target *default_bfd_vec = &DEFAULT_BFD_VEC;
 566 #else
 567 static const bfd_target *default_bfd_vec;
 568 #endif
 569
 570 void
 571 initialize_current_architecture (void)
 572 {
 573   const char **arches = gdbarch_printable_names ();
 574
 575   /* determine a default architecture and byte order. */
 576   struct gdbarch_info info;
 577   memset (&info, 0, sizeof (info));
 578
 579   /* Find a default architecture. */
 580   if (info.bfd_arch_info == NULL
 581       && default_bfd_arch != NULL)
 582     info.bfd_arch_info = default_bfd_arch;
 583   if (info.bfd_arch_info == NULL)
 584     {
 585       /* Choose the architecture by taking the first one
 586          alphabetically. */
 587       const char *chosen = arches[0];
 588       const char **arch;
 589       for (arch = arches; *arch != NULL; arch++)
 590         {
 591           if (strcmp (*arch, chosen) < 0)
 592             chosen = *arch;
 593         }
 594       if (chosen == NULL)
 595         internal_error ("initialize_current_architecture: No arch");
 596       info.bfd_arch_info = bfd_scan_arch (chosen);
 597       if (info.bfd_arch_info == NULL)
 598         internal_error ("initialize_current_architecture: Arch not found");
 599     }
 600
 601   /* take several guesses at a byte order. */
 602   /* NB: can't use TARGET_BYTE_ORDER_DEFAULT as its definition is
 603      forced above. */
 604   if (info.byte_order == 0
 605       && default_bfd_vec != NULL)
 606     {
 607       /* Extract BFD's default vector's byte order. */
 608       switch (default_bfd_vec->byteorder)
 609         {
 610         case BFD_ENDIAN_BIG:
 611           info.byte_order = BIG_ENDIAN;
 612           break;
 613         case BFD_ENDIAN_LITTLE:
 614           info.byte_order = LITTLE_ENDIAN;
 615           break;
 616         default:
 617           break;
 618         }
 619     }
 620   if (info.byte_order == 0)
 621     {
 622       /* look for ``*el-*'' in the target name. */
 623       const char *chp;
 624       chp = strchr (target_name, '-');
 625       if (chp != NULL
 626           && chp - 2 >= target_name
 627           && strncmp (chp - 2, "el", 2) == 0)
 628         info.byte_order = LITTLE_ENDIAN;
 629     }
 630   if (info.byte_order == 0)
 631     {
 632       /* Wire it to big-endian!!! */
 633       info.byte_order = BIG_ENDIAN;
 634     }
 635
 636   if (GDB_MULTI_ARCH)
 637     {
 638       gdbarch_update (info);
 639     }
 640
 641   /* Create the ``set architecture'' command appending ``auto'' to the
 642      list of architectures. */
 643   {
 644     struct cmd_list_element *c;
 645     /* Append ``auto''. */
 646     int nr;
 647     for (nr = 0; arches[nr] != NULL; nr++);
 648     arches = xrealloc (arches, sizeof (char*) * (nr + 2));
 649     arches[nr + 0] = "auto";
 650     arches[nr + 1] = NULL;
 651     /* FIXME: add_set_enum_cmd() uses an array of ``char *'' instead
 652        of ``const char *''.  We just happen to know that the casts are
 653        safe. */
 654     c = add_set_enum_cmd ("architecture", class_support,
 655                           arches, &set_architecture_string,
 656                           "Set architecture of target.",
 657                           &setlist);
 658     c->function.sfunc = set_architecture;
 659     add_alias_cmd ("processor", "architecture", class_support, 1, &setlist);
 660     /* Don't use set_from_show - need to print both auto/manual and
 661        current setting. */
 662     add_cmd ("architecture", class_support, show_architecture,
 663              "Show the current target architecture", &showlist);
 664     c = add_cmd ("architecture", class_support, info_architecture,
 665                  "List supported target architectures", &infolist);
 666     deprecate_cmd (c, "set architecture");
 667   }
 668 }
 669
 670
 671 /* */
 672
 673 extern initialize_file_ftype _initialize_gdbarch_utils;
 674
 675 void
 676 _initialize_gdbarch_utils (void)
 677 {
 678   struct cmd_list_element *c;
 679   c = add_set_enum_cmd ("endian", class_support,
 680                         endian_enum, &set_endian_string,
 681                         "Set endianness of target.",
 682                         &setlist);
 683   c->function.sfunc = set_endian;
 684   /* Don't use set_from_show - need to print both auto/manual and
 685      current setting. */
 686   add_cmd ("endian", class_support, show_endian,
 687            "Show the current byte-order", &showlist);
 688 }