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"));
210 /* Assume the world is sane, every register's virtual and real size
214 generic_register_size (int regnum)
216 gdb_assert (regnum >= 0 && regnum < NUM_REGS + NUM_PSEUDO_REGS);
217 return TYPE_LENGTH (register_type (current_gdbarch, regnum));
220 /* Assume all registers are adjacent. */
223 generic_register_byte (int regnum)
227 gdb_assert (regnum >= 0 && regnum < NUM_REGS + NUM_PSEUDO_REGS);
229 for (i = 0; i < regnum; i++)
231 byte += generic_register_size (i);
238 legacy_pc_in_sigtramp (CORE_ADDR pc, char *name)
240 #if defined (DEPRECATED_IN_SIGTRAMP)
241 return DEPRECATED_IN_SIGTRAMP (pc, name);
243 return name && strcmp ("_sigtramp", name) == 0;
248 generic_convert_register_p (int regnum, struct type *type)
254 default_stabs_argument_has_addr (struct gdbarch *gdbarch, struct type *type)
260 generic_instruction_nullified (struct gdbarch *gdbarch,
261 struct regcache *regcache)
267 default_remote_register_number (struct gdbarch *gdbarch,
274 /* Functions to manipulate the endianness of the target. */
276 static int target_byte_order_user = BFD_ENDIAN_UNKNOWN;
278 static const char endian_big[] = "big";
279 static const char endian_little[] = "little";
280 static const char endian_auto[] = "auto";
281 static const char *endian_enum[] =
288 static const char *set_endian_string;
290 /* Called by ``show endian''. */
293 show_endian (struct ui_file *file, int from_tty, struct cmd_list_element *c,
296 if (target_byte_order_user == BFD_ENDIAN_UNKNOWN)
297 if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
298 fprintf_unfiltered (file, _("The target endianness is set automatically "
299 "(currently big endian)\n"));
301 fprintf_unfiltered (file, _("The target endianness is set automatically "
302 "(currently little endian)\n"));
304 if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
305 fprintf_unfiltered (file,
306 _("The target is assumed to be big endian\n"));
308 fprintf_unfiltered (file,
309 _("The target is assumed to be little endian\n"));
313 set_endian (char *ignore_args, int from_tty, struct cmd_list_element *c)
315 struct gdbarch_info info;
317 gdbarch_info_init (&info);
319 if (set_endian_string == endian_auto)
321 target_byte_order_user = BFD_ENDIAN_UNKNOWN;
322 if (! gdbarch_update_p (info))
323 internal_error (__FILE__, __LINE__,
324 _("set_endian: architecture update failed"));
326 else if (set_endian_string == endian_little)
328 info.byte_order = BFD_ENDIAN_LITTLE;
329 if (! gdbarch_update_p (info))
330 printf_unfiltered (_("Little endian target not supported by GDB\n"));
332 target_byte_order_user = BFD_ENDIAN_LITTLE;
334 else if (set_endian_string == endian_big)
336 info.byte_order = BFD_ENDIAN_BIG;
337 if (! gdbarch_update_p (info))
338 printf_unfiltered (_("Big endian target not supported by GDB\n"));
340 target_byte_order_user = BFD_ENDIAN_BIG;
343 internal_error (__FILE__, __LINE__,
344 _("set_endian: bad value"));
346 show_endian (gdb_stdout, from_tty, NULL, NULL);
349 /* Given SELECTED, a currently selected BFD architecture, and
350 FROM_TARGET, a BFD architecture reported by the target description,
351 return what architecture to use. Either may be NULL; if both are
352 specified, we use the more specific. If the two are obviously
353 incompatible, warn the user. */
355 static const struct bfd_arch_info *
356 choose_architecture_for_target (const struct bfd_arch_info *selected,
357 const struct bfd_arch_info *from_target)
359 const struct bfd_arch_info *compat1, *compat2;
361 if (selected == NULL)
364 if (from_target == NULL)
367 /* struct bfd_arch_info objects are singletons: that is, there's
368 supposed to be exactly one instance for a given machine. So you
369 can tell whether two are equivalent by comparing pointers. */
370 if (from_target == selected)
373 /* BFD's 'A->compatible (A, B)' functions return zero if A and B are
374 incompatible. But if they are compatible, it returns the 'more
375 featureful' of the two arches. That is, if A can run code
376 written for B, but B can't run code written for A, then it'll
379 Some targets (e.g. MIPS as of 2006-12-04) don't fully
380 implement this, instead always returning NULL or the first
381 argument. We detect that case by checking both directions. */
383 compat1 = selected->compatible (selected, from_target);
384 compat2 = from_target->compatible (from_target, selected);
386 if (compat1 == NULL && compat2 == NULL)
388 warning (_("Selected architecture %s is not compatible "
389 "with reported target architecture %s"),
390 selected->printable_name, from_target->printable_name);
398 if (compat1 == compat2)
401 /* If the two didn't match, but one of them was a default architecture,
402 assume the more specific one is correct. This handles the case
403 where an executable or target description just says "mips", but
404 the other knows which MIPS variant. */
405 if (compat1->the_default)
407 if (compat2->the_default)
410 /* We have no idea which one is better. This is a bug, but not
411 a critical problem; warn the user. */
412 warning (_("Selected architecture %s is ambiguous with "
413 "reported target architecture %s"),
414 selected->printable_name, from_target->printable_name);
418 /* Functions to manipulate the architecture of the target */
420 enum set_arch { set_arch_auto, set_arch_manual };
422 static const struct bfd_arch_info *target_architecture_user;
424 static const char *set_architecture_string;
427 selected_architecture_name (void)
429 if (target_architecture_user == NULL)
432 return set_architecture_string;
435 /* Called if the user enters ``show architecture'' without an
439 show_architecture (struct ui_file *file, int from_tty,
440 struct cmd_list_element *c, const char *value)
443 arch = TARGET_ARCHITECTURE->printable_name;
444 if (target_architecture_user == NULL)
445 fprintf_filtered (file, _("\
446 The target architecture is set automatically (currently %s)\n"), arch);
448 fprintf_filtered (file, _("\
449 The target architecture is assumed to be %s\n"), arch);
453 /* Called if the user enters ``set architecture'' with or without an
457 set_architecture (char *ignore_args, int from_tty, struct cmd_list_element *c)
459 struct gdbarch_info info;
461 gdbarch_info_init (&info);
463 if (strcmp (set_architecture_string, "auto") == 0)
465 target_architecture_user = NULL;
466 if (!gdbarch_update_p (info))
467 internal_error (__FILE__, __LINE__,
468 _("could not select an architecture automatically"));
472 info.bfd_arch_info = bfd_scan_arch (set_architecture_string);
473 if (info.bfd_arch_info == NULL)
474 internal_error (__FILE__, __LINE__,
475 _("set_architecture: bfd_scan_arch failed"));
476 if (gdbarch_update_p (info))
477 target_architecture_user = info.bfd_arch_info;
479 printf_unfiltered (_("Architecture `%s' not recognized.\n"),
480 set_architecture_string);
482 show_architecture (gdb_stdout, from_tty, NULL, NULL);
485 /* Try to select a global architecture that matches "info". Return
486 non-zero if the attempt succeds. */
488 gdbarch_update_p (struct gdbarch_info info)
490 struct gdbarch *new_gdbarch = gdbarch_find_by_info (info);
492 /* If there no architecture by that name, reject the request. */
493 if (new_gdbarch == NULL)
496 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
497 "Architecture not found\n");
501 /* If it is the same old architecture, accept the request (but don't
503 if (new_gdbarch == current_gdbarch)
506 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
507 "Architecture 0x%08lx (%s) unchanged\n",
509 gdbarch_bfd_arch_info (new_gdbarch)->printable_name);
513 /* It's a new architecture, swap it in. */
515 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
516 "New architecture 0x%08lx (%s) selected\n",
518 gdbarch_bfd_arch_info (new_gdbarch)->printable_name);
519 deprecated_current_gdbarch_select_hack (new_gdbarch);
524 /* Return the architecture for ABFD. If no suitable architecture
525 could be find, return NULL. */
528 gdbarch_from_bfd (bfd *abfd)
530 struct gdbarch *old_gdbarch = current_gdbarch;
531 struct gdbarch *new_gdbarch;
532 struct gdbarch_info info;
534 /* If we call gdbarch_find_by_info without filling in info.abfd,
535 then it will use the global exec_bfd. That's fine if we don't
536 have one of those either. And that's the only time we should
537 reach here with a NULL ABFD argument - when we are discarding
539 gdb_assert (abfd != NULL || exec_bfd == NULL);
541 gdbarch_info_init (&info);
543 return gdbarch_find_by_info (info);
546 /* Set the dynamic target-system-dependent parameters (architecture,
547 byte-order) using information found in the BFD */
550 set_gdbarch_from_file (bfd *abfd)
552 struct gdbarch *gdbarch;
554 gdbarch = gdbarch_from_bfd (abfd);
556 error (_("Architecture of file not recognized."));
557 deprecated_current_gdbarch_select_hack (gdbarch);
560 /* Initialize the current architecture. Update the ``set
561 architecture'' command so that it specifies a list of valid
564 #ifdef DEFAULT_BFD_ARCH
565 extern const bfd_arch_info_type DEFAULT_BFD_ARCH;
566 static const bfd_arch_info_type *default_bfd_arch = &DEFAULT_BFD_ARCH;
568 static const bfd_arch_info_type *default_bfd_arch;
571 #ifdef DEFAULT_BFD_VEC
572 extern const bfd_target DEFAULT_BFD_VEC;
573 static const bfd_target *default_bfd_vec = &DEFAULT_BFD_VEC;
575 static const bfd_target *default_bfd_vec;
578 static int default_byte_order = BFD_ENDIAN_UNKNOWN;
581 initialize_current_architecture (void)
583 const char **arches = gdbarch_printable_names ();
585 /* determine a default architecture and byte order. */
586 struct gdbarch_info info;
587 gdbarch_info_init (&info);
589 /* Find a default architecture. */
590 if (default_bfd_arch == NULL)
592 /* Choose the architecture by taking the first one
594 const char *chosen = arches[0];
596 for (arch = arches; *arch != NULL; arch++)
598 if (strcmp (*arch, chosen) < 0)
602 internal_error (__FILE__, __LINE__,
603 _("initialize_current_architecture: No arch"));
604 default_bfd_arch = bfd_scan_arch (chosen);
605 if (default_bfd_arch == NULL)
606 internal_error (__FILE__, __LINE__,
607 _("initialize_current_architecture: Arch not found"));
610 info.bfd_arch_info = default_bfd_arch;
612 /* Take several guesses at a byte order. */
613 if (default_byte_order == BFD_ENDIAN_UNKNOWN
614 && default_bfd_vec != NULL)
616 /* Extract BFD's default vector's byte order. */
617 switch (default_bfd_vec->byteorder)
620 default_byte_order = BFD_ENDIAN_BIG;
622 case BFD_ENDIAN_LITTLE:
623 default_byte_order = BFD_ENDIAN_LITTLE;
629 if (default_byte_order == BFD_ENDIAN_UNKNOWN)
631 /* look for ``*el-*'' in the target name. */
633 chp = strchr (target_name, '-');
635 && chp - 2 >= target_name
636 && strncmp (chp - 2, "el", 2) == 0)
637 default_byte_order = BFD_ENDIAN_LITTLE;
639 if (default_byte_order == BFD_ENDIAN_UNKNOWN)
641 /* Wire it to big-endian!!! */
642 default_byte_order = BFD_ENDIAN_BIG;
645 info.byte_order = default_byte_order;
647 if (! gdbarch_update_p (info))
648 internal_error (__FILE__, __LINE__,
649 _("initialize_current_architecture: Selection of "
650 "initial architecture failed"));
652 /* Create the ``set architecture'' command appending ``auto'' to the
653 list of architectures. */
655 struct cmd_list_element *c;
656 /* Append ``auto''. */
658 for (nr = 0; arches[nr] != NULL; nr++);
659 arches = xrealloc (arches, sizeof (char*) * (nr + 2));
660 arches[nr + 0] = "auto";
661 arches[nr + 1] = NULL;
662 add_setshow_enum_cmd ("architecture", class_support,
663 arches, &set_architecture_string, _("\
664 Set architecture of target."), _("\
665 Show architecture of target."), NULL,
666 set_architecture, show_architecture,
667 &setlist, &showlist);
668 add_alias_cmd ("processor", "architecture", class_support, 1, &setlist);
673 /* Initialize a gdbarch info to values that will be automatically
674 overridden. Note: Originally, this ``struct info'' was initialized
675 using memset(0). Unfortunately, that ran into problems, namely
676 BFD_ENDIAN_BIG is zero. An explicit initialization function that
677 can explicitly set each field to a well defined value is used. */
680 gdbarch_info_init (struct gdbarch_info *info)
682 memset (info, 0, sizeof (struct gdbarch_info));
683 info->byte_order = BFD_ENDIAN_UNKNOWN;
684 info->osabi = GDB_OSABI_UNINITIALIZED;
687 /* Similar to init, but this time fill in the blanks. Information is
688 obtained from the global "set ..." options and explicitly
689 initialized INFO fields. */
692 gdbarch_info_fill (struct gdbarch_info *info)
694 /* Check for the current file. */
695 if (info->abfd == NULL)
696 info->abfd = exec_bfd;
698 /* Check for the current target description. */
699 if (info->target_desc == NULL)
700 info->target_desc = target_current_description ();
702 /* "(gdb) set architecture ...". */
703 if (info->bfd_arch_info == NULL
704 && target_architecture_user)
705 info->bfd_arch_info = target_architecture_user;
707 if (info->bfd_arch_info == NULL
708 && info->abfd != NULL
709 && bfd_get_arch (info->abfd) != bfd_arch_unknown
710 && bfd_get_arch (info->abfd) != bfd_arch_obscure)
711 info->bfd_arch_info = bfd_get_arch_info (info->abfd);
712 /* From the target. */
713 if (info->target_desc != NULL)
714 info->bfd_arch_info = choose_architecture_for_target
715 (info->bfd_arch_info, tdesc_architecture (info->target_desc));
716 /* From the default. */
717 if (info->bfd_arch_info == NULL)
718 info->bfd_arch_info = default_bfd_arch;
720 /* "(gdb) set byte-order ...". */
721 if (info->byte_order == BFD_ENDIAN_UNKNOWN
722 && target_byte_order_user != BFD_ENDIAN_UNKNOWN)
723 info->byte_order = target_byte_order_user;
724 /* From the INFO struct. */
725 if (info->byte_order == BFD_ENDIAN_UNKNOWN
726 && info->abfd != NULL)
727 info->byte_order = (bfd_big_endian (info->abfd) ? BFD_ENDIAN_BIG
728 : bfd_little_endian (info->abfd) ? BFD_ENDIAN_LITTLE
729 : BFD_ENDIAN_UNKNOWN);
730 /* From the default. */
731 if (info->byte_order == BFD_ENDIAN_UNKNOWN)
732 info->byte_order = default_byte_order;
734 /* "(gdb) set osabi ...". Handled by gdbarch_lookup_osabi. */
735 if (info->osabi == GDB_OSABI_UNINITIALIZED)
736 info->osabi = gdbarch_lookup_osabi (info->abfd);
738 /* Must have at least filled in the architecture. */
739 gdb_assert (info->bfd_arch_info != NULL);
744 extern initialize_file_ftype _initialize_gdbarch_utils; /* -Wmissing-prototypes */
747 _initialize_gdbarch_utils (void)
749 struct cmd_list_element *c;
750 add_setshow_enum_cmd ("endian", class_support,
751 endian_enum, &set_endian_string, _("\
752 Set endianness of target."), _("\
753 Show endianness of target."), NULL,
754 set_endian, show_endian,
755 &setlist, &showlist);