1 /* Dynamic architecture support for GDB, the GNU debugger.
3 Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
4 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
23 #include "arch-utils.h"
26 #include "inferior.h" /* enum CALL_DUMMY_LOCATION et.al. */
27 #include "gdb_string.h"
29 #include "gdb_assert.h"
30 #include "sim-regno.h"
33 #include "target-descriptions.h"
37 #include "floatformat.h"
41 legacy_register_sim_regno (struct gdbarch *gdbarch, int regnum)
43 /* Only makes sense to supply raw registers. */
44 gdb_assert (regnum >= 0 && regnum < gdbarch_num_regs (gdbarch));
45 /* NOTE: cagney/2002-05-13: The old code did it this way and it is
46 suspected that some GDB/SIM combinations may rely on this
47 behavour. The default should be one2one_register_sim_regno
49 if (gdbarch_register_name (gdbarch, regnum) != NULL
50 && gdbarch_register_name (gdbarch, regnum)[0] != '\0')
53 return LEGACY_SIM_REGNO_IGNORE;
57 generic_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
63 generic_skip_solib_resolver (struct gdbarch *gdbarch, CORE_ADDR pc)
69 generic_in_solib_return_trampoline (CORE_ADDR pc, char *name)
75 generic_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc)
80 /* Helper functions for gdbarch_inner_than */
83 core_addr_lessthan (CORE_ADDR lhs, CORE_ADDR rhs)
89 core_addr_greaterthan (CORE_ADDR lhs, CORE_ADDR rhs)
94 /* Misc helper functions for targets. */
97 core_addr_identity (CORE_ADDR addr)
103 convert_from_func_ptr_addr_identity (struct gdbarch *gdbarch, CORE_ADDR addr,
104 struct target_ops *targ)
110 no_op_reg_to_regnum (struct gdbarch *gdbarch, int reg)
116 default_elf_make_msymbol_special (asymbol *sym, struct minimal_symbol *msym)
122 default_coff_make_msymbol_special (int val, struct minimal_symbol *msym)
128 cannot_register_not (struct gdbarch *gdbarch, int regnum)
133 /* Legacy version of target_virtual_frame_pointer(). Assumes that
134 there is an gdbarch_deprecated_fp_regnum and that it is the same, cooked or
138 legacy_virtual_frame_pointer (struct gdbarch *gdbarch,
141 LONGEST *frame_offset)
143 /* FIXME: cagney/2002-09-13: This code is used when identifying the
144 frame pointer of the current PC. It is assuming that a single
145 register and an offset can determine this. I think it should
146 instead generate a byte code expression as that would work better
147 with things like Dwarf2's CFI. */
148 if (gdbarch_deprecated_fp_regnum (gdbarch) >= 0
149 && gdbarch_deprecated_fp_regnum (gdbarch)
150 < gdbarch_num_regs (gdbarch))
151 *frame_regnum = gdbarch_deprecated_fp_regnum (gdbarch);
152 else if (gdbarch_sp_regnum (gdbarch) >= 0
153 && gdbarch_sp_regnum (gdbarch)
154 < gdbarch_num_regs (gdbarch))
155 *frame_regnum = gdbarch_sp_regnum (gdbarch);
157 /* Should this be an internal error? I guess so, it is reflecting
158 an architectural limitation in the current design. */
159 internal_error (__FILE__, __LINE__, _("No virtual frame pointer available"));
165 generic_convert_register_p (struct gdbarch *gdbarch, int regnum,
172 default_stabs_argument_has_addr (struct gdbarch *gdbarch, struct type *type)
178 generic_instruction_nullified (struct gdbarch *gdbarch,
179 struct regcache *regcache)
185 default_remote_register_number (struct gdbarch *gdbarch,
192 /* Functions to manipulate the endianness of the target. */
194 static int target_byte_order_user = BFD_ENDIAN_UNKNOWN;
196 static const char endian_big[] = "big";
197 static const char endian_little[] = "little";
198 static const char endian_auto[] = "auto";
199 static const char *endian_enum[] =
206 static const char *set_endian_string;
209 selected_byte_order (void)
211 if (target_byte_order_user != BFD_ENDIAN_UNKNOWN)
212 return gdbarch_byte_order (current_gdbarch);
214 return BFD_ENDIAN_UNKNOWN;
217 /* Called by ``show endian''. */
220 show_endian (struct ui_file *file, int from_tty, struct cmd_list_element *c,
223 if (target_byte_order_user == BFD_ENDIAN_UNKNOWN)
224 if (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG)
225 fprintf_unfiltered (file, _("The target endianness is set automatically "
226 "(currently big endian)\n"));
228 fprintf_unfiltered (file, _("The target endianness is set automatically "
229 "(currently little endian)\n"));
231 if (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG)
232 fprintf_unfiltered (file,
233 _("The target is assumed to be big endian\n"));
235 fprintf_unfiltered (file,
236 _("The target is assumed to be little endian\n"));
240 set_endian (char *ignore_args, int from_tty, struct cmd_list_element *c)
242 struct gdbarch_info info;
244 gdbarch_info_init (&info);
246 if (set_endian_string == endian_auto)
248 target_byte_order_user = BFD_ENDIAN_UNKNOWN;
249 if (! gdbarch_update_p (info))
250 internal_error (__FILE__, __LINE__,
251 _("set_endian: architecture update failed"));
253 else if (set_endian_string == endian_little)
255 info.byte_order = BFD_ENDIAN_LITTLE;
256 if (! gdbarch_update_p (info))
257 printf_unfiltered (_("Little endian target not supported by GDB\n"));
259 target_byte_order_user = BFD_ENDIAN_LITTLE;
261 else if (set_endian_string == endian_big)
263 info.byte_order = BFD_ENDIAN_BIG;
264 if (! gdbarch_update_p (info))
265 printf_unfiltered (_("Big endian target not supported by GDB\n"));
267 target_byte_order_user = BFD_ENDIAN_BIG;
270 internal_error (__FILE__, __LINE__,
271 _("set_endian: bad value"));
273 show_endian (gdb_stdout, from_tty, NULL, NULL);
276 /* Given SELECTED, a currently selected BFD architecture, and
277 FROM_TARGET, a BFD architecture reported by the target description,
278 return what architecture to use. Either may be NULL; if both are
279 specified, we use the more specific. If the two are obviously
280 incompatible, warn the user. */
282 static const struct bfd_arch_info *
283 choose_architecture_for_target (const struct bfd_arch_info *selected,
284 const struct bfd_arch_info *from_target)
286 const struct bfd_arch_info *compat1, *compat2;
288 if (selected == NULL)
291 if (from_target == NULL)
294 /* struct bfd_arch_info objects are singletons: that is, there's
295 supposed to be exactly one instance for a given machine. So you
296 can tell whether two are equivalent by comparing pointers. */
297 if (from_target == selected)
300 /* BFD's 'A->compatible (A, B)' functions return zero if A and B are
301 incompatible. But if they are compatible, it returns the 'more
302 featureful' of the two arches. That is, if A can run code
303 written for B, but B can't run code written for A, then it'll
306 Some targets (e.g. MIPS as of 2006-12-04) don't fully
307 implement this, instead always returning NULL or the first
308 argument. We detect that case by checking both directions. */
310 compat1 = selected->compatible (selected, from_target);
311 compat2 = from_target->compatible (from_target, selected);
313 if (compat1 == NULL && compat2 == NULL)
315 warning (_("Selected architecture %s is not compatible "
316 "with reported target architecture %s"),
317 selected->printable_name, from_target->printable_name);
325 if (compat1 == compat2)
328 /* If the two didn't match, but one of them was a default architecture,
329 assume the more specific one is correct. This handles the case
330 where an executable or target description just says "mips", but
331 the other knows which MIPS variant. */
332 if (compat1->the_default)
334 if (compat2->the_default)
337 /* We have no idea which one is better. This is a bug, but not
338 a critical problem; warn the user. */
339 warning (_("Selected architecture %s is ambiguous with "
340 "reported target architecture %s"),
341 selected->printable_name, from_target->printable_name);
345 /* Functions to manipulate the architecture of the target */
347 enum set_arch { set_arch_auto, set_arch_manual };
349 static const struct bfd_arch_info *target_architecture_user;
351 static const char *set_architecture_string;
354 selected_architecture_name (void)
356 if (target_architecture_user == NULL)
359 return set_architecture_string;
362 /* Called if the user enters ``show architecture'' without an
366 show_architecture (struct ui_file *file, int from_tty,
367 struct cmd_list_element *c, const char *value)
370 arch = gdbarch_bfd_arch_info (current_gdbarch)->printable_name;
371 if (target_architecture_user == NULL)
372 fprintf_filtered (file, _("\
373 The target architecture is set automatically (currently %s)\n"), arch);
375 fprintf_filtered (file, _("\
376 The target architecture is assumed to be %s\n"), arch);
380 /* Called if the user enters ``set architecture'' with or without an
384 set_architecture (char *ignore_args, int from_tty, struct cmd_list_element *c)
386 struct gdbarch_info info;
388 gdbarch_info_init (&info);
390 if (strcmp (set_architecture_string, "auto") == 0)
392 target_architecture_user = NULL;
393 if (!gdbarch_update_p (info))
394 internal_error (__FILE__, __LINE__,
395 _("could not select an architecture automatically"));
399 info.bfd_arch_info = bfd_scan_arch (set_architecture_string);
400 if (info.bfd_arch_info == NULL)
401 internal_error (__FILE__, __LINE__,
402 _("set_architecture: bfd_scan_arch failed"));
403 if (gdbarch_update_p (info))
404 target_architecture_user = info.bfd_arch_info;
406 printf_unfiltered (_("Architecture `%s' not recognized.\n"),
407 set_architecture_string);
409 show_architecture (gdb_stdout, from_tty, NULL, NULL);
412 /* Try to select a global architecture that matches "info". Return
413 non-zero if the attempt succeds. */
415 gdbarch_update_p (struct gdbarch_info info)
417 struct gdbarch *new_gdbarch = gdbarch_find_by_info (info);
419 /* If there no architecture by that name, reject the request. */
420 if (new_gdbarch == NULL)
423 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
424 "Architecture not found\n");
428 /* If it is the same old architecture, accept the request (but don't
430 if (new_gdbarch == current_gdbarch)
433 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
434 "Architecture 0x%08lx (%s) unchanged\n",
436 gdbarch_bfd_arch_info (new_gdbarch)->printable_name);
440 /* It's a new architecture, swap it in. */
442 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
443 "New architecture 0x%08lx (%s) selected\n",
445 gdbarch_bfd_arch_info (new_gdbarch)->printable_name);
446 deprecated_current_gdbarch_select_hack (new_gdbarch);
451 /* Return the architecture for ABFD. If no suitable architecture
452 could be find, return NULL. */
455 gdbarch_from_bfd (bfd *abfd)
457 struct gdbarch *old_gdbarch = current_gdbarch;
458 struct gdbarch *new_gdbarch;
459 struct gdbarch_info info;
461 /* If we call gdbarch_find_by_info without filling in info.abfd,
462 then it will use the global exec_bfd. That's fine if we don't
463 have one of those either. And that's the only time we should
464 reach here with a NULL ABFD argument - when we are discarding
466 gdb_assert (abfd != NULL || exec_bfd == NULL);
468 gdbarch_info_init (&info);
470 return gdbarch_find_by_info (info);
473 /* Set the dynamic target-system-dependent parameters (architecture,
474 byte-order) using information found in the BFD */
477 set_gdbarch_from_file (bfd *abfd)
479 struct gdbarch *gdbarch;
481 gdbarch = gdbarch_from_bfd (abfd);
483 error (_("Architecture of file not recognized."));
484 deprecated_current_gdbarch_select_hack (gdbarch);
487 /* Initialize the current architecture. Update the ``set
488 architecture'' command so that it specifies a list of valid
491 #ifdef DEFAULT_BFD_ARCH
492 extern const bfd_arch_info_type DEFAULT_BFD_ARCH;
493 static const bfd_arch_info_type *default_bfd_arch = &DEFAULT_BFD_ARCH;
495 static const bfd_arch_info_type *default_bfd_arch;
498 #ifdef DEFAULT_BFD_VEC
499 extern const bfd_target DEFAULT_BFD_VEC;
500 static const bfd_target *default_bfd_vec = &DEFAULT_BFD_VEC;
502 static const bfd_target *default_bfd_vec;
505 static int default_byte_order = BFD_ENDIAN_UNKNOWN;
508 initialize_current_architecture (void)
510 const char **arches = gdbarch_printable_names ();
512 /* determine a default architecture and byte order. */
513 struct gdbarch_info info;
514 gdbarch_info_init (&info);
516 /* Find a default architecture. */
517 if (default_bfd_arch == NULL)
519 /* Choose the architecture by taking the first one
521 const char *chosen = arches[0];
523 for (arch = arches; *arch != NULL; arch++)
525 if (strcmp (*arch, chosen) < 0)
529 internal_error (__FILE__, __LINE__,
530 _("initialize_current_architecture: No arch"));
531 default_bfd_arch = bfd_scan_arch (chosen);
532 if (default_bfd_arch == NULL)
533 internal_error (__FILE__, __LINE__,
534 _("initialize_current_architecture: Arch not found"));
537 info.bfd_arch_info = default_bfd_arch;
539 /* Take several guesses at a byte order. */
540 if (default_byte_order == BFD_ENDIAN_UNKNOWN
541 && default_bfd_vec != NULL)
543 /* Extract BFD's default vector's byte order. */
544 switch (default_bfd_vec->byteorder)
547 default_byte_order = BFD_ENDIAN_BIG;
549 case BFD_ENDIAN_LITTLE:
550 default_byte_order = BFD_ENDIAN_LITTLE;
556 if (default_byte_order == BFD_ENDIAN_UNKNOWN)
558 /* look for ``*el-*'' in the target name. */
560 chp = strchr (target_name, '-');
562 && chp - 2 >= target_name
563 && strncmp (chp - 2, "el", 2) == 0)
564 default_byte_order = BFD_ENDIAN_LITTLE;
566 if (default_byte_order == BFD_ENDIAN_UNKNOWN)
568 /* Wire it to big-endian!!! */
569 default_byte_order = BFD_ENDIAN_BIG;
572 info.byte_order = default_byte_order;
574 if (! gdbarch_update_p (info))
575 internal_error (__FILE__, __LINE__,
576 _("initialize_current_architecture: Selection of "
577 "initial architecture failed"));
579 /* Create the ``set architecture'' command appending ``auto'' to the
580 list of architectures. */
582 struct cmd_list_element *c;
583 /* Append ``auto''. */
585 for (nr = 0; arches[nr] != NULL; nr++);
586 arches = xrealloc (arches, sizeof (char*) * (nr + 2));
587 arches[nr + 0] = "auto";
588 arches[nr + 1] = NULL;
589 add_setshow_enum_cmd ("architecture", class_support,
590 arches, &set_architecture_string, _("\
591 Set architecture of target."), _("\
592 Show architecture of target."), NULL,
593 set_architecture, show_architecture,
594 &setlist, &showlist);
595 add_alias_cmd ("processor", "architecture", class_support, 1, &setlist);
600 /* Initialize a gdbarch info to values that will be automatically
601 overridden. Note: Originally, this ``struct info'' was initialized
602 using memset(0). Unfortunately, that ran into problems, namely
603 BFD_ENDIAN_BIG is zero. An explicit initialization function that
604 can explicitly set each field to a well defined value is used. */
607 gdbarch_info_init (struct gdbarch_info *info)
609 memset (info, 0, sizeof (struct gdbarch_info));
610 info->byte_order = BFD_ENDIAN_UNKNOWN;
611 info->osabi = GDB_OSABI_UNINITIALIZED;
614 /* Similar to init, but this time fill in the blanks. Information is
615 obtained from the global "set ..." options and explicitly
616 initialized INFO fields. */
619 gdbarch_info_fill (struct gdbarch_info *info)
621 /* Check for the current file. */
622 if (info->abfd == NULL)
623 info->abfd = exec_bfd;
624 if (info->abfd == NULL)
625 info->abfd = core_bfd;
627 /* Check for the current target description. */
628 if (info->target_desc == NULL)
629 info->target_desc = target_current_description ();
631 /* "(gdb) set architecture ...". */
632 if (info->bfd_arch_info == NULL
633 && target_architecture_user)
634 info->bfd_arch_info = target_architecture_user;
636 if (info->bfd_arch_info == NULL
637 && info->abfd != NULL
638 && bfd_get_arch (info->abfd) != bfd_arch_unknown
639 && bfd_get_arch (info->abfd) != bfd_arch_obscure)
640 info->bfd_arch_info = bfd_get_arch_info (info->abfd);
641 /* From the target. */
642 if (info->target_desc != NULL)
643 info->bfd_arch_info = choose_architecture_for_target
644 (info->bfd_arch_info, tdesc_architecture (info->target_desc));
645 /* From the default. */
646 if (info->bfd_arch_info == NULL)
647 info->bfd_arch_info = default_bfd_arch;
649 /* "(gdb) set byte-order ...". */
650 if (info->byte_order == BFD_ENDIAN_UNKNOWN
651 && target_byte_order_user != BFD_ENDIAN_UNKNOWN)
652 info->byte_order = target_byte_order_user;
653 /* From the INFO struct. */
654 if (info->byte_order == BFD_ENDIAN_UNKNOWN
655 && info->abfd != NULL)
656 info->byte_order = (bfd_big_endian (info->abfd) ? BFD_ENDIAN_BIG
657 : bfd_little_endian (info->abfd) ? BFD_ENDIAN_LITTLE
658 : BFD_ENDIAN_UNKNOWN);
659 /* From the default. */
660 if (info->byte_order == BFD_ENDIAN_UNKNOWN)
661 info->byte_order = default_byte_order;
663 /* "(gdb) set osabi ...". Handled by gdbarch_lookup_osabi. */
664 if (info->osabi == GDB_OSABI_UNINITIALIZED)
665 info->osabi = gdbarch_lookup_osabi (info->abfd);
667 /* Must have at least filled in the architecture. */
668 gdb_assert (info->bfd_arch_info != NULL);
673 extern initialize_file_ftype _initialize_gdbarch_utils; /* -Wmissing-prototypes */
676 _initialize_gdbarch_utils (void)
678 struct cmd_list_element *c;
679 add_setshow_enum_cmd ("endian", class_support,
680 endian_enum, &set_endian_string, _("\
681 Set endianness of target."), _("\
682 Show endianness of target."), NULL,
683 set_endian, show_endian,
684 &setlist, &showlist);