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 2 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, write to the Free Software
20 Foundation, Inc., 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA. */
25 #include "arch-utils.h"
28 #include "inferior.h" /* enum CALL_DUMMY_LOCATION et.al. */
29 #include "gdb_string.h"
31 #include "gdb_assert.h"
32 #include "sim-regno.h"
35 #include "target-descriptions.h"
39 #include "floatformat.h"
42 always_use_struct_convention (int gcc_p, struct type *value_type)
47 enum return_value_convention
48 legacy_return_value (struct gdbarch *gdbarch, struct type *valtype,
49 struct regcache *regcache, gdb_byte *readbuf,
50 const gdb_byte *writebuf)
52 /* NOTE: cagney/2004-06-13: The gcc_p parameter to
53 USE_STRUCT_CONVENTION isn't used. */
54 int struct_return = ((TYPE_CODE (valtype) == TYPE_CODE_STRUCT
55 || TYPE_CODE (valtype) == TYPE_CODE_UNION
56 || TYPE_CODE (valtype) == TYPE_CODE_ARRAY)
57 && DEPRECATED_USE_STRUCT_CONVENTION (0, valtype));
61 gdb_assert (!struct_return);
62 /* NOTE: cagney/2004-06-13: See stack.c:return_command. Old
63 architectures don't expect STORE_RETURN_VALUE to handle small
64 structures. Should not be called with such types. */
65 gdb_assert (TYPE_CODE (valtype) != TYPE_CODE_STRUCT
66 && TYPE_CODE (valtype) != TYPE_CODE_UNION);
67 STORE_RETURN_VALUE (valtype, regcache, writebuf);
72 gdb_assert (!struct_return);
73 EXTRACT_RETURN_VALUE (valtype, regcache, readbuf);
77 return RETURN_VALUE_STRUCT_CONVENTION;
79 return RETURN_VALUE_REGISTER_CONVENTION;
83 legacy_register_sim_regno (int regnum)
85 /* Only makes sense to supply raw registers. */
86 gdb_assert (regnum >= 0 && regnum < NUM_REGS);
87 /* NOTE: cagney/2002-05-13: The old code did it this way and it is
88 suspected that some GDB/SIM combinations may rely on this
89 behavour. The default should be one2one_register_sim_regno
91 if (REGISTER_NAME (regnum) != NULL
92 && REGISTER_NAME (regnum)[0] != '\0')
95 return LEGACY_SIM_REGNO_IGNORE;
99 generic_skip_trampoline_code (CORE_ADDR pc)
105 generic_skip_solib_resolver (struct gdbarch *gdbarch, CORE_ADDR pc)
111 generic_in_solib_return_trampoline (CORE_ADDR pc, char *name)
117 generic_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc)
123 generic_remote_translate_xfer_address (struct gdbarch *gdbarch,
124 struct regcache *regcache,
125 CORE_ADDR gdb_addr, int gdb_len,
126 CORE_ADDR * rem_addr, int *rem_len)
128 *rem_addr = gdb_addr;
132 /* Helper functions for INNER_THAN */
135 core_addr_lessthan (CORE_ADDR lhs, CORE_ADDR rhs)
141 core_addr_greaterthan (CORE_ADDR lhs, CORE_ADDR rhs)
146 /* Misc helper functions for targets. */
149 core_addr_identity (CORE_ADDR addr)
155 convert_from_func_ptr_addr_identity (struct gdbarch *gdbarch, CORE_ADDR addr,
156 struct target_ops *targ)
162 no_op_reg_to_regnum (int reg)
168 default_elf_make_msymbol_special (asymbol *sym, struct minimal_symbol *msym)
174 default_coff_make_msymbol_special (int val, struct minimal_symbol *msym)
180 cannot_register_not (int regnum)
185 /* Legacy version of target_virtual_frame_pointer(). Assumes that
186 there is an DEPRECATED_FP_REGNUM and that it is the same, cooked or
190 legacy_virtual_frame_pointer (CORE_ADDR pc,
192 LONGEST *frame_offset)
194 /* FIXME: cagney/2002-09-13: This code is used when identifying the
195 frame pointer of the current PC. It is assuming that a single
196 register and an offset can determine this. I think it should
197 instead generate a byte code expression as that would work better
198 with things like Dwarf2's CFI. */
199 if (DEPRECATED_FP_REGNUM >= 0 && DEPRECATED_FP_REGNUM < NUM_REGS)
200 *frame_regnum = DEPRECATED_FP_REGNUM;
201 else if (SP_REGNUM >= 0 && SP_REGNUM < NUM_REGS)
202 *frame_regnum = SP_REGNUM;
204 /* Should this be an internal error? I guess so, it is reflecting
205 an architectural limitation in the current design. */
206 internal_error (__FILE__, __LINE__, _("No virtual frame pointer available"));
212 generic_convert_register_p (int regnum, struct type *type)
218 default_stabs_argument_has_addr (struct gdbarch *gdbarch, struct type *type)
224 generic_instruction_nullified (struct gdbarch *gdbarch,
225 struct regcache *regcache)
231 default_remote_register_number (struct gdbarch *gdbarch,
238 /* Functions to manipulate the endianness of the target. */
240 static int target_byte_order_user = BFD_ENDIAN_UNKNOWN;
242 static const char endian_big[] = "big";
243 static const char endian_little[] = "little";
244 static const char endian_auto[] = "auto";
245 static const char *endian_enum[] =
252 static const char *set_endian_string;
255 selected_byte_order (void)
257 if (target_byte_order_user != BFD_ENDIAN_UNKNOWN)
258 return TARGET_BYTE_ORDER;
260 return BFD_ENDIAN_UNKNOWN;
263 /* Called by ``show endian''. */
266 show_endian (struct ui_file *file, int from_tty, struct cmd_list_element *c,
269 if (target_byte_order_user == BFD_ENDIAN_UNKNOWN)
270 if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
271 fprintf_unfiltered (file, _("The target endianness is set automatically "
272 "(currently big endian)\n"));
274 fprintf_unfiltered (file, _("The target endianness is set automatically "
275 "(currently little endian)\n"));
277 if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
278 fprintf_unfiltered (file,
279 _("The target is assumed to be big endian\n"));
281 fprintf_unfiltered (file,
282 _("The target is assumed to be little endian\n"));
286 set_endian (char *ignore_args, int from_tty, struct cmd_list_element *c)
288 struct gdbarch_info info;
290 gdbarch_info_init (&info);
292 if (set_endian_string == endian_auto)
294 target_byte_order_user = BFD_ENDIAN_UNKNOWN;
295 if (! gdbarch_update_p (info))
296 internal_error (__FILE__, __LINE__,
297 _("set_endian: architecture update failed"));
299 else if (set_endian_string == endian_little)
301 info.byte_order = BFD_ENDIAN_LITTLE;
302 if (! gdbarch_update_p (info))
303 printf_unfiltered (_("Little endian target not supported by GDB\n"));
305 target_byte_order_user = BFD_ENDIAN_LITTLE;
307 else if (set_endian_string == endian_big)
309 info.byte_order = BFD_ENDIAN_BIG;
310 if (! gdbarch_update_p (info))
311 printf_unfiltered (_("Big endian target not supported by GDB\n"));
313 target_byte_order_user = BFD_ENDIAN_BIG;
316 internal_error (__FILE__, __LINE__,
317 _("set_endian: bad value"));
319 show_endian (gdb_stdout, from_tty, NULL, NULL);
322 /* Given SELECTED, a currently selected BFD architecture, and
323 FROM_TARGET, a BFD architecture reported by the target description,
324 return what architecture to use. Either may be NULL; if both are
325 specified, we use the more specific. If the two are obviously
326 incompatible, warn the user. */
328 static const struct bfd_arch_info *
329 choose_architecture_for_target (const struct bfd_arch_info *selected,
330 const struct bfd_arch_info *from_target)
332 const struct bfd_arch_info *compat1, *compat2;
334 if (selected == NULL)
337 if (from_target == NULL)
340 /* struct bfd_arch_info objects are singletons: that is, there's
341 supposed to be exactly one instance for a given machine. So you
342 can tell whether two are equivalent by comparing pointers. */
343 if (from_target == selected)
346 /* BFD's 'A->compatible (A, B)' functions return zero if A and B are
347 incompatible. But if they are compatible, it returns the 'more
348 featureful' of the two arches. That is, if A can run code
349 written for B, but B can't run code written for A, then it'll
352 Some targets (e.g. MIPS as of 2006-12-04) don't fully
353 implement this, instead always returning NULL or the first
354 argument. We detect that case by checking both directions. */
356 compat1 = selected->compatible (selected, from_target);
357 compat2 = from_target->compatible (from_target, selected);
359 if (compat1 == NULL && compat2 == NULL)
361 warning (_("Selected architecture %s is not compatible "
362 "with reported target architecture %s"),
363 selected->printable_name, from_target->printable_name);
371 if (compat1 == compat2)
374 /* If the two didn't match, but one of them was a default architecture,
375 assume the more specific one is correct. This handles the case
376 where an executable or target description just says "mips", but
377 the other knows which MIPS variant. */
378 if (compat1->the_default)
380 if (compat2->the_default)
383 /* We have no idea which one is better. This is a bug, but not
384 a critical problem; warn the user. */
385 warning (_("Selected architecture %s is ambiguous with "
386 "reported target architecture %s"),
387 selected->printable_name, from_target->printable_name);
391 /* Functions to manipulate the architecture of the target */
393 enum set_arch { set_arch_auto, set_arch_manual };
395 static const struct bfd_arch_info *target_architecture_user;
397 static const char *set_architecture_string;
400 selected_architecture_name (void)
402 if (target_architecture_user == NULL)
405 return set_architecture_string;
408 /* Called if the user enters ``show architecture'' without an
412 show_architecture (struct ui_file *file, int from_tty,
413 struct cmd_list_element *c, const char *value)
416 arch = TARGET_ARCHITECTURE->printable_name;
417 if (target_architecture_user == NULL)
418 fprintf_filtered (file, _("\
419 The target architecture is set automatically (currently %s)\n"), arch);
421 fprintf_filtered (file, _("\
422 The target architecture is assumed to be %s\n"), arch);
426 /* Called if the user enters ``set architecture'' with or without an
430 set_architecture (char *ignore_args, int from_tty, struct cmd_list_element *c)
432 struct gdbarch_info info;
434 gdbarch_info_init (&info);
436 if (strcmp (set_architecture_string, "auto") == 0)
438 target_architecture_user = NULL;
439 if (!gdbarch_update_p (info))
440 internal_error (__FILE__, __LINE__,
441 _("could not select an architecture automatically"));
445 info.bfd_arch_info = bfd_scan_arch (set_architecture_string);
446 if (info.bfd_arch_info == NULL)
447 internal_error (__FILE__, __LINE__,
448 _("set_architecture: bfd_scan_arch failed"));
449 if (gdbarch_update_p (info))
450 target_architecture_user = info.bfd_arch_info;
452 printf_unfiltered (_("Architecture `%s' not recognized.\n"),
453 set_architecture_string);
455 show_architecture (gdb_stdout, from_tty, NULL, NULL);
458 /* Try to select a global architecture that matches "info". Return
459 non-zero if the attempt succeds. */
461 gdbarch_update_p (struct gdbarch_info info)
463 struct gdbarch *new_gdbarch = gdbarch_find_by_info (info);
465 /* If there no architecture by that name, reject the request. */
466 if (new_gdbarch == NULL)
469 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
470 "Architecture not found\n");
474 /* If it is the same old architecture, accept the request (but don't
476 if (new_gdbarch == current_gdbarch)
479 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
480 "Architecture 0x%08lx (%s) unchanged\n",
482 gdbarch_bfd_arch_info (new_gdbarch)->printable_name);
486 /* It's a new architecture, swap it in. */
488 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
489 "New architecture 0x%08lx (%s) selected\n",
491 gdbarch_bfd_arch_info (new_gdbarch)->printable_name);
492 deprecated_current_gdbarch_select_hack (new_gdbarch);
497 /* Return the architecture for ABFD. If no suitable architecture
498 could be find, return NULL. */
501 gdbarch_from_bfd (bfd *abfd)
503 struct gdbarch *old_gdbarch = current_gdbarch;
504 struct gdbarch *new_gdbarch;
505 struct gdbarch_info info;
507 /* If we call gdbarch_find_by_info without filling in info.abfd,
508 then it will use the global exec_bfd. That's fine if we don't
509 have one of those either. And that's the only time we should
510 reach here with a NULL ABFD argument - when we are discarding
512 gdb_assert (abfd != NULL || exec_bfd == NULL);
514 gdbarch_info_init (&info);
516 return gdbarch_find_by_info (info);
519 /* Set the dynamic target-system-dependent parameters (architecture,
520 byte-order) using information found in the BFD */
523 set_gdbarch_from_file (bfd *abfd)
525 struct gdbarch *gdbarch;
527 gdbarch = gdbarch_from_bfd (abfd);
529 error (_("Architecture of file not recognized."));
530 deprecated_current_gdbarch_select_hack (gdbarch);
533 /* Initialize the current architecture. Update the ``set
534 architecture'' command so that it specifies a list of valid
537 #ifdef DEFAULT_BFD_ARCH
538 extern const bfd_arch_info_type DEFAULT_BFD_ARCH;
539 static const bfd_arch_info_type *default_bfd_arch = &DEFAULT_BFD_ARCH;
541 static const bfd_arch_info_type *default_bfd_arch;
544 #ifdef DEFAULT_BFD_VEC
545 extern const bfd_target DEFAULT_BFD_VEC;
546 static const bfd_target *default_bfd_vec = &DEFAULT_BFD_VEC;
548 static const bfd_target *default_bfd_vec;
551 static int default_byte_order = BFD_ENDIAN_UNKNOWN;
554 initialize_current_architecture (void)
556 const char **arches = gdbarch_printable_names ();
558 /* determine a default architecture and byte order. */
559 struct gdbarch_info info;
560 gdbarch_info_init (&info);
562 /* Find a default architecture. */
563 if (default_bfd_arch == NULL)
565 /* Choose the architecture by taking the first one
567 const char *chosen = arches[0];
569 for (arch = arches; *arch != NULL; arch++)
571 if (strcmp (*arch, chosen) < 0)
575 internal_error (__FILE__, __LINE__,
576 _("initialize_current_architecture: No arch"));
577 default_bfd_arch = bfd_scan_arch (chosen);
578 if (default_bfd_arch == NULL)
579 internal_error (__FILE__, __LINE__,
580 _("initialize_current_architecture: Arch not found"));
583 info.bfd_arch_info = default_bfd_arch;
585 /* Take several guesses at a byte order. */
586 if (default_byte_order == BFD_ENDIAN_UNKNOWN
587 && default_bfd_vec != NULL)
589 /* Extract BFD's default vector's byte order. */
590 switch (default_bfd_vec->byteorder)
593 default_byte_order = BFD_ENDIAN_BIG;
595 case BFD_ENDIAN_LITTLE:
596 default_byte_order = BFD_ENDIAN_LITTLE;
602 if (default_byte_order == BFD_ENDIAN_UNKNOWN)
604 /* look for ``*el-*'' in the target name. */
606 chp = strchr (target_name, '-');
608 && chp - 2 >= target_name
609 && strncmp (chp - 2, "el", 2) == 0)
610 default_byte_order = BFD_ENDIAN_LITTLE;
612 if (default_byte_order == BFD_ENDIAN_UNKNOWN)
614 /* Wire it to big-endian!!! */
615 default_byte_order = BFD_ENDIAN_BIG;
618 info.byte_order = default_byte_order;
620 if (! gdbarch_update_p (info))
621 internal_error (__FILE__, __LINE__,
622 _("initialize_current_architecture: Selection of "
623 "initial architecture failed"));
625 /* Create the ``set architecture'' command appending ``auto'' to the
626 list of architectures. */
628 struct cmd_list_element *c;
629 /* Append ``auto''. */
631 for (nr = 0; arches[nr] != NULL; nr++);
632 arches = xrealloc (arches, sizeof (char*) * (nr + 2));
633 arches[nr + 0] = "auto";
634 arches[nr + 1] = NULL;
635 add_setshow_enum_cmd ("architecture", class_support,
636 arches, &set_architecture_string, _("\
637 Set architecture of target."), _("\
638 Show architecture of target."), NULL,
639 set_architecture, show_architecture,
640 &setlist, &showlist);
641 add_alias_cmd ("processor", "architecture", class_support, 1, &setlist);
646 /* Initialize a gdbarch info to values that will be automatically
647 overridden. Note: Originally, this ``struct info'' was initialized
648 using memset(0). Unfortunately, that ran into problems, namely
649 BFD_ENDIAN_BIG is zero. An explicit initialization function that
650 can explicitly set each field to a well defined value is used. */
653 gdbarch_info_init (struct gdbarch_info *info)
655 memset (info, 0, sizeof (struct gdbarch_info));
656 info->byte_order = BFD_ENDIAN_UNKNOWN;
657 info->osabi = GDB_OSABI_UNINITIALIZED;
660 /* Similar to init, but this time fill in the blanks. Information is
661 obtained from the global "set ..." options and explicitly
662 initialized INFO fields. */
665 gdbarch_info_fill (struct gdbarch_info *info)
667 /* Check for the current file. */
668 if (info->abfd == NULL)
669 info->abfd = exec_bfd;
671 /* Check for the current target description. */
672 if (info->target_desc == NULL)
673 info->target_desc = target_current_description ();
675 /* "(gdb) set architecture ...". */
676 if (info->bfd_arch_info == NULL
677 && target_architecture_user)
678 info->bfd_arch_info = target_architecture_user;
680 if (info->bfd_arch_info == NULL
681 && info->abfd != NULL
682 && bfd_get_arch (info->abfd) != bfd_arch_unknown
683 && bfd_get_arch (info->abfd) != bfd_arch_obscure)
684 info->bfd_arch_info = bfd_get_arch_info (info->abfd);
685 /* From the target. */
686 if (info->target_desc != NULL)
687 info->bfd_arch_info = choose_architecture_for_target
688 (info->bfd_arch_info, tdesc_architecture (info->target_desc));
689 /* From the default. */
690 if (info->bfd_arch_info == NULL)
691 info->bfd_arch_info = default_bfd_arch;
693 /* "(gdb) set byte-order ...". */
694 if (info->byte_order == BFD_ENDIAN_UNKNOWN
695 && target_byte_order_user != BFD_ENDIAN_UNKNOWN)
696 info->byte_order = target_byte_order_user;
697 /* From the INFO struct. */
698 if (info->byte_order == BFD_ENDIAN_UNKNOWN
699 && info->abfd != NULL)
700 info->byte_order = (bfd_big_endian (info->abfd) ? BFD_ENDIAN_BIG
701 : bfd_little_endian (info->abfd) ? BFD_ENDIAN_LITTLE
702 : BFD_ENDIAN_UNKNOWN);
703 /* From the default. */
704 if (info->byte_order == BFD_ENDIAN_UNKNOWN)
705 info->byte_order = default_byte_order;
707 /* "(gdb) set osabi ...". Handled by gdbarch_lookup_osabi. */
708 if (info->osabi == GDB_OSABI_UNINITIALIZED)
709 info->osabi = gdbarch_lookup_osabi (info->abfd);
711 /* Must have at least filled in the architecture. */
712 gdb_assert (info->bfd_arch_info != NULL);
717 extern initialize_file_ftype _initialize_gdbarch_utils; /* -Wmissing-prototypes */
720 _initialize_gdbarch_utils (void)
722 struct cmd_list_element *c;
723 add_setshow_enum_cmd ("endian", class_support,
724 endian_enum, &set_endian_string, _("\
725 Set endianness of target."), _("\
726 Show endianness of target."), NULL,
727 set_endian, show_endian,
728 &setlist, &showlist);