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 (int regnum)
43 /* Only makes sense to supply raw registers. */
44 gdb_assert (regnum >= 0 && regnum < gdbarch_num_regs (current_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 (current_gdbarch, regnum) != NULL
50 && gdbarch_register_name (current_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 (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 (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 (int regnum, struct type *type)
171 default_stabs_argument_has_addr (struct gdbarch *gdbarch, struct type *type)
177 generic_instruction_nullified (struct gdbarch *gdbarch,
178 struct regcache *regcache)
184 default_remote_register_number (struct gdbarch *gdbarch,
191 /* Functions to manipulate the endianness of the target. */
193 static int target_byte_order_user = BFD_ENDIAN_UNKNOWN;
195 static const char endian_big[] = "big";
196 static const char endian_little[] = "little";
197 static const char endian_auto[] = "auto";
198 static const char *endian_enum[] =
205 static const char *set_endian_string;
208 selected_byte_order (void)
210 if (target_byte_order_user != BFD_ENDIAN_UNKNOWN)
211 return gdbarch_byte_order (current_gdbarch);
213 return BFD_ENDIAN_UNKNOWN;
216 /* Called by ``show endian''. */
219 show_endian (struct ui_file *file, int from_tty, struct cmd_list_element *c,
222 if (target_byte_order_user == BFD_ENDIAN_UNKNOWN)
223 if (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG)
224 fprintf_unfiltered (file, _("The target endianness is set automatically "
225 "(currently big endian)\n"));
227 fprintf_unfiltered (file, _("The target endianness is set automatically "
228 "(currently little endian)\n"));
230 if (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG)
231 fprintf_unfiltered (file,
232 _("The target is assumed to be big endian\n"));
234 fprintf_unfiltered (file,
235 _("The target is assumed to be little endian\n"));
239 set_endian (char *ignore_args, int from_tty, struct cmd_list_element *c)
241 struct gdbarch_info info;
243 gdbarch_info_init (&info);
245 if (set_endian_string == endian_auto)
247 target_byte_order_user = BFD_ENDIAN_UNKNOWN;
248 if (! gdbarch_update_p (info))
249 internal_error (__FILE__, __LINE__,
250 _("set_endian: architecture update failed"));
252 else if (set_endian_string == endian_little)
254 info.byte_order = BFD_ENDIAN_LITTLE;
255 if (! gdbarch_update_p (info))
256 printf_unfiltered (_("Little endian target not supported by GDB\n"));
258 target_byte_order_user = BFD_ENDIAN_LITTLE;
260 else if (set_endian_string == endian_big)
262 info.byte_order = BFD_ENDIAN_BIG;
263 if (! gdbarch_update_p (info))
264 printf_unfiltered (_("Big endian target not supported by GDB\n"));
266 target_byte_order_user = BFD_ENDIAN_BIG;
269 internal_error (__FILE__, __LINE__,
270 _("set_endian: bad value"));
272 show_endian (gdb_stdout, from_tty, NULL, NULL);
275 /* Given SELECTED, a currently selected BFD architecture, and
276 FROM_TARGET, a BFD architecture reported by the target description,
277 return what architecture to use. Either may be NULL; if both are
278 specified, we use the more specific. If the two are obviously
279 incompatible, warn the user. */
281 static const struct bfd_arch_info *
282 choose_architecture_for_target (const struct bfd_arch_info *selected,
283 const struct bfd_arch_info *from_target)
285 const struct bfd_arch_info *compat1, *compat2;
287 if (selected == NULL)
290 if (from_target == NULL)
293 /* struct bfd_arch_info objects are singletons: that is, there's
294 supposed to be exactly one instance for a given machine. So you
295 can tell whether two are equivalent by comparing pointers. */
296 if (from_target == selected)
299 /* BFD's 'A->compatible (A, B)' functions return zero if A and B are
300 incompatible. But if they are compatible, it returns the 'more
301 featureful' of the two arches. That is, if A can run code
302 written for B, but B can't run code written for A, then it'll
305 Some targets (e.g. MIPS as of 2006-12-04) don't fully
306 implement this, instead always returning NULL or the first
307 argument. We detect that case by checking both directions. */
309 compat1 = selected->compatible (selected, from_target);
310 compat2 = from_target->compatible (from_target, selected);
312 if (compat1 == NULL && compat2 == NULL)
314 warning (_("Selected architecture %s is not compatible "
315 "with reported target architecture %s"),
316 selected->printable_name, from_target->printable_name);
324 if (compat1 == compat2)
327 /* If the two didn't match, but one of them was a default architecture,
328 assume the more specific one is correct. This handles the case
329 where an executable or target description just says "mips", but
330 the other knows which MIPS variant. */
331 if (compat1->the_default)
333 if (compat2->the_default)
336 /* We have no idea which one is better. This is a bug, but not
337 a critical problem; warn the user. */
338 warning (_("Selected architecture %s is ambiguous with "
339 "reported target architecture %s"),
340 selected->printable_name, from_target->printable_name);
344 /* Functions to manipulate the architecture of the target */
346 enum set_arch { set_arch_auto, set_arch_manual };
348 static const struct bfd_arch_info *target_architecture_user;
350 static const char *set_architecture_string;
353 selected_architecture_name (void)
355 if (target_architecture_user == NULL)
358 return set_architecture_string;
361 /* Called if the user enters ``show architecture'' without an
365 show_architecture (struct ui_file *file, int from_tty,
366 struct cmd_list_element *c, const char *value)
369 arch = gdbarch_bfd_arch_info (current_gdbarch)->printable_name;
370 if (target_architecture_user == NULL)
371 fprintf_filtered (file, _("\
372 The target architecture is set automatically (currently %s)\n"), arch);
374 fprintf_filtered (file, _("\
375 The target architecture is assumed to be %s\n"), arch);
379 /* Called if the user enters ``set architecture'' with or without an
383 set_architecture (char *ignore_args, int from_tty, struct cmd_list_element *c)
385 struct gdbarch_info info;
387 gdbarch_info_init (&info);
389 if (strcmp (set_architecture_string, "auto") == 0)
391 target_architecture_user = NULL;
392 if (!gdbarch_update_p (info))
393 internal_error (__FILE__, __LINE__,
394 _("could not select an architecture automatically"));
398 info.bfd_arch_info = bfd_scan_arch (set_architecture_string);
399 if (info.bfd_arch_info == NULL)
400 internal_error (__FILE__, __LINE__,
401 _("set_architecture: bfd_scan_arch failed"));
402 if (gdbarch_update_p (info))
403 target_architecture_user = info.bfd_arch_info;
405 printf_unfiltered (_("Architecture `%s' not recognized.\n"),
406 set_architecture_string);
408 show_architecture (gdb_stdout, from_tty, NULL, NULL);
411 /* Try to select a global architecture that matches "info". Return
412 non-zero if the attempt succeds. */
414 gdbarch_update_p (struct gdbarch_info info)
416 struct gdbarch *new_gdbarch = gdbarch_find_by_info (info);
418 /* If there no architecture by that name, reject the request. */
419 if (new_gdbarch == NULL)
422 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
423 "Architecture not found\n");
427 /* If it is the same old architecture, accept the request (but don't
429 if (new_gdbarch == current_gdbarch)
432 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
433 "Architecture 0x%08lx (%s) unchanged\n",
435 gdbarch_bfd_arch_info (new_gdbarch)->printable_name);
439 /* It's a new architecture, swap it in. */
441 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
442 "New architecture 0x%08lx (%s) selected\n",
444 gdbarch_bfd_arch_info (new_gdbarch)->printable_name);
445 deprecated_current_gdbarch_select_hack (new_gdbarch);
450 /* Return the architecture for ABFD. If no suitable architecture
451 could be find, return NULL. */
454 gdbarch_from_bfd (bfd *abfd)
456 struct gdbarch *old_gdbarch = current_gdbarch;
457 struct gdbarch *new_gdbarch;
458 struct gdbarch_info info;
460 /* If we call gdbarch_find_by_info without filling in info.abfd,
461 then it will use the global exec_bfd. That's fine if we don't
462 have one of those either. And that's the only time we should
463 reach here with a NULL ABFD argument - when we are discarding
465 gdb_assert (abfd != NULL || exec_bfd == NULL);
467 gdbarch_info_init (&info);
469 return gdbarch_find_by_info (info);
472 /* Set the dynamic target-system-dependent parameters (architecture,
473 byte-order) using information found in the BFD */
476 set_gdbarch_from_file (bfd *abfd)
478 struct gdbarch *gdbarch;
480 gdbarch = gdbarch_from_bfd (abfd);
482 error (_("Architecture of file not recognized."));
483 deprecated_current_gdbarch_select_hack (gdbarch);
486 /* Initialize the current architecture. Update the ``set
487 architecture'' command so that it specifies a list of valid
490 #ifdef DEFAULT_BFD_ARCH
491 extern const bfd_arch_info_type DEFAULT_BFD_ARCH;
492 static const bfd_arch_info_type *default_bfd_arch = &DEFAULT_BFD_ARCH;
494 static const bfd_arch_info_type *default_bfd_arch;
497 #ifdef DEFAULT_BFD_VEC
498 extern const bfd_target DEFAULT_BFD_VEC;
499 static const bfd_target *default_bfd_vec = &DEFAULT_BFD_VEC;
501 static const bfd_target *default_bfd_vec;
504 static int default_byte_order = BFD_ENDIAN_UNKNOWN;
507 initialize_current_architecture (void)
509 const char **arches = gdbarch_printable_names ();
511 /* determine a default architecture and byte order. */
512 struct gdbarch_info info;
513 gdbarch_info_init (&info);
515 /* Find a default architecture. */
516 if (default_bfd_arch == NULL)
518 /* Choose the architecture by taking the first one
520 const char *chosen = arches[0];
522 for (arch = arches; *arch != NULL; arch++)
524 if (strcmp (*arch, chosen) < 0)
528 internal_error (__FILE__, __LINE__,
529 _("initialize_current_architecture: No arch"));
530 default_bfd_arch = bfd_scan_arch (chosen);
531 if (default_bfd_arch == NULL)
532 internal_error (__FILE__, __LINE__,
533 _("initialize_current_architecture: Arch not found"));
536 info.bfd_arch_info = default_bfd_arch;
538 /* Take several guesses at a byte order. */
539 if (default_byte_order == BFD_ENDIAN_UNKNOWN
540 && default_bfd_vec != NULL)
542 /* Extract BFD's default vector's byte order. */
543 switch (default_bfd_vec->byteorder)
546 default_byte_order = BFD_ENDIAN_BIG;
548 case BFD_ENDIAN_LITTLE:
549 default_byte_order = BFD_ENDIAN_LITTLE;
555 if (default_byte_order == BFD_ENDIAN_UNKNOWN)
557 /* look for ``*el-*'' in the target name. */
559 chp = strchr (target_name, '-');
561 && chp - 2 >= target_name
562 && strncmp (chp - 2, "el", 2) == 0)
563 default_byte_order = BFD_ENDIAN_LITTLE;
565 if (default_byte_order == BFD_ENDIAN_UNKNOWN)
567 /* Wire it to big-endian!!! */
568 default_byte_order = BFD_ENDIAN_BIG;
571 info.byte_order = default_byte_order;
573 if (! gdbarch_update_p (info))
574 internal_error (__FILE__, __LINE__,
575 _("initialize_current_architecture: Selection of "
576 "initial architecture failed"));
578 /* Create the ``set architecture'' command appending ``auto'' to the
579 list of architectures. */
581 struct cmd_list_element *c;
582 /* Append ``auto''. */
584 for (nr = 0; arches[nr] != NULL; nr++);
585 arches = xrealloc (arches, sizeof (char*) * (nr + 2));
586 arches[nr + 0] = "auto";
587 arches[nr + 1] = NULL;
588 add_setshow_enum_cmd ("architecture", class_support,
589 arches, &set_architecture_string, _("\
590 Set architecture of target."), _("\
591 Show architecture of target."), NULL,
592 set_architecture, show_architecture,
593 &setlist, &showlist);
594 add_alias_cmd ("processor", "architecture", class_support, 1, &setlist);
599 /* Initialize a gdbarch info to values that will be automatically
600 overridden. Note: Originally, this ``struct info'' was initialized
601 using memset(0). Unfortunately, that ran into problems, namely
602 BFD_ENDIAN_BIG is zero. An explicit initialization function that
603 can explicitly set each field to a well defined value is used. */
606 gdbarch_info_init (struct gdbarch_info *info)
608 memset (info, 0, sizeof (struct gdbarch_info));
609 info->byte_order = BFD_ENDIAN_UNKNOWN;
610 info->osabi = GDB_OSABI_UNINITIALIZED;
613 /* Similar to init, but this time fill in the blanks. Information is
614 obtained from the global "set ..." options and explicitly
615 initialized INFO fields. */
618 gdbarch_info_fill (struct gdbarch_info *info)
620 /* Check for the current file. */
621 if (info->abfd == NULL)
622 info->abfd = exec_bfd;
623 if (info->abfd == NULL)
624 info->abfd = core_bfd;
626 /* Check for the current target description. */
627 if (info->target_desc == NULL)
628 info->target_desc = target_current_description ();
630 /* "(gdb) set architecture ...". */
631 if (info->bfd_arch_info == NULL
632 && target_architecture_user)
633 info->bfd_arch_info = target_architecture_user;
635 if (info->bfd_arch_info == NULL
636 && info->abfd != NULL
637 && bfd_get_arch (info->abfd) != bfd_arch_unknown
638 && bfd_get_arch (info->abfd) != bfd_arch_obscure)
639 info->bfd_arch_info = bfd_get_arch_info (info->abfd);
640 /* From the target. */
641 if (info->target_desc != NULL)
642 info->bfd_arch_info = choose_architecture_for_target
643 (info->bfd_arch_info, tdesc_architecture (info->target_desc));
644 /* From the default. */
645 if (info->bfd_arch_info == NULL)
646 info->bfd_arch_info = default_bfd_arch;
648 /* "(gdb) set byte-order ...". */
649 if (info->byte_order == BFD_ENDIAN_UNKNOWN
650 && target_byte_order_user != BFD_ENDIAN_UNKNOWN)
651 info->byte_order = target_byte_order_user;
652 /* From the INFO struct. */
653 if (info->byte_order == BFD_ENDIAN_UNKNOWN
654 && info->abfd != NULL)
655 info->byte_order = (bfd_big_endian (info->abfd) ? BFD_ENDIAN_BIG
656 : bfd_little_endian (info->abfd) ? BFD_ENDIAN_LITTLE
657 : BFD_ENDIAN_UNKNOWN);
658 /* From the default. */
659 if (info->byte_order == BFD_ENDIAN_UNKNOWN)
660 info->byte_order = default_byte_order;
662 /* "(gdb) set osabi ...". Handled by gdbarch_lookup_osabi. */
663 if (info->osabi == GDB_OSABI_UNINITIALIZED)
664 info->osabi = gdbarch_lookup_osabi (info->abfd);
666 /* Must have at least filled in the architecture. */
667 gdb_assert (info->bfd_arch_info != NULL);
672 extern initialize_file_ftype _initialize_gdbarch_utils; /* -Wmissing-prototypes */
675 _initialize_gdbarch_utils (void)
677 struct cmd_list_element *c;
678 add_setshow_enum_cmd ("endian", class_support,
679 endian_enum, &set_endian_string, _("\
680 Set endianness of target."), _("\
681 Show endianness of target."), NULL,
682 set_endian, show_endian,
683 &setlist, &showlist);