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)
122 /* Helper functions for INNER_THAN */
125 core_addr_lessthan (CORE_ADDR lhs, CORE_ADDR rhs)
131 core_addr_greaterthan (CORE_ADDR lhs, CORE_ADDR rhs)
136 /* Misc helper functions for targets. */
139 core_addr_identity (CORE_ADDR addr)
145 convert_from_func_ptr_addr_identity (struct gdbarch *gdbarch, CORE_ADDR addr,
146 struct target_ops *targ)
152 no_op_reg_to_regnum (int reg)
158 default_elf_make_msymbol_special (asymbol *sym, struct minimal_symbol *msym)
164 default_coff_make_msymbol_special (int val, struct minimal_symbol *msym)
170 cannot_register_not (int regnum)
175 /* Legacy version of target_virtual_frame_pointer(). Assumes that
176 there is an DEPRECATED_FP_REGNUM and that it is the same, cooked or
180 legacy_virtual_frame_pointer (CORE_ADDR pc,
182 LONGEST *frame_offset)
184 /* FIXME: cagney/2002-09-13: This code is used when identifying the
185 frame pointer of the current PC. It is assuming that a single
186 register and an offset can determine this. I think it should
187 instead generate a byte code expression as that would work better
188 with things like Dwarf2's CFI. */
189 if (DEPRECATED_FP_REGNUM >= 0 && DEPRECATED_FP_REGNUM < NUM_REGS)
190 *frame_regnum = DEPRECATED_FP_REGNUM;
191 else if (SP_REGNUM >= 0 && SP_REGNUM < NUM_REGS)
192 *frame_regnum = SP_REGNUM;
194 /* Should this be an internal error? I guess so, it is reflecting
195 an architectural limitation in the current design. */
196 internal_error (__FILE__, __LINE__, _("No virtual frame pointer available"));
202 generic_convert_register_p (int regnum, struct type *type)
208 default_stabs_argument_has_addr (struct gdbarch *gdbarch, struct type *type)
214 generic_instruction_nullified (struct gdbarch *gdbarch,
215 struct regcache *regcache)
221 default_remote_register_number (struct gdbarch *gdbarch,
228 /* Functions to manipulate the endianness of the target. */
230 static int target_byte_order_user = BFD_ENDIAN_UNKNOWN;
232 static const char endian_big[] = "big";
233 static const char endian_little[] = "little";
234 static const char endian_auto[] = "auto";
235 static const char *endian_enum[] =
242 static const char *set_endian_string;
245 selected_byte_order (void)
247 if (target_byte_order_user != BFD_ENDIAN_UNKNOWN)
248 return gdbarch_byte_order (current_gdbarch);
250 return BFD_ENDIAN_UNKNOWN;
253 /* Called by ``show endian''. */
256 show_endian (struct ui_file *file, int from_tty, struct cmd_list_element *c,
259 if (target_byte_order_user == BFD_ENDIAN_UNKNOWN)
260 if (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG)
261 fprintf_unfiltered (file, _("The target endianness is set automatically "
262 "(currently big endian)\n"));
264 fprintf_unfiltered (file, _("The target endianness is set automatically "
265 "(currently little endian)\n"));
267 if (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG)
268 fprintf_unfiltered (file,
269 _("The target is assumed to be big endian\n"));
271 fprintf_unfiltered (file,
272 _("The target is assumed to be little endian\n"));
276 set_endian (char *ignore_args, int from_tty, struct cmd_list_element *c)
278 struct gdbarch_info info;
280 gdbarch_info_init (&info);
282 if (set_endian_string == endian_auto)
284 target_byte_order_user = BFD_ENDIAN_UNKNOWN;
285 if (! gdbarch_update_p (info))
286 internal_error (__FILE__, __LINE__,
287 _("set_endian: architecture update failed"));
289 else if (set_endian_string == endian_little)
291 info.byte_order = BFD_ENDIAN_LITTLE;
292 if (! gdbarch_update_p (info))
293 printf_unfiltered (_("Little endian target not supported by GDB\n"));
295 target_byte_order_user = BFD_ENDIAN_LITTLE;
297 else if (set_endian_string == endian_big)
299 info.byte_order = BFD_ENDIAN_BIG;
300 if (! gdbarch_update_p (info))
301 printf_unfiltered (_("Big endian target not supported by GDB\n"));
303 target_byte_order_user = BFD_ENDIAN_BIG;
306 internal_error (__FILE__, __LINE__,
307 _("set_endian: bad value"));
309 show_endian (gdb_stdout, from_tty, NULL, NULL);
312 /* Given SELECTED, a currently selected BFD architecture, and
313 FROM_TARGET, a BFD architecture reported by the target description,
314 return what architecture to use. Either may be NULL; if both are
315 specified, we use the more specific. If the two are obviously
316 incompatible, warn the user. */
318 static const struct bfd_arch_info *
319 choose_architecture_for_target (const struct bfd_arch_info *selected,
320 const struct bfd_arch_info *from_target)
322 const struct bfd_arch_info *compat1, *compat2;
324 if (selected == NULL)
327 if (from_target == NULL)
330 /* struct bfd_arch_info objects are singletons: that is, there's
331 supposed to be exactly one instance for a given machine. So you
332 can tell whether two are equivalent by comparing pointers. */
333 if (from_target == selected)
336 /* BFD's 'A->compatible (A, B)' functions return zero if A and B are
337 incompatible. But if they are compatible, it returns the 'more
338 featureful' of the two arches. That is, if A can run code
339 written for B, but B can't run code written for A, then it'll
342 Some targets (e.g. MIPS as of 2006-12-04) don't fully
343 implement this, instead always returning NULL or the first
344 argument. We detect that case by checking both directions. */
346 compat1 = selected->compatible (selected, from_target);
347 compat2 = from_target->compatible (from_target, selected);
349 if (compat1 == NULL && compat2 == NULL)
351 warning (_("Selected architecture %s is not compatible "
352 "with reported target architecture %s"),
353 selected->printable_name, from_target->printable_name);
361 if (compat1 == compat2)
364 /* If the two didn't match, but one of them was a default architecture,
365 assume the more specific one is correct. This handles the case
366 where an executable or target description just says "mips", but
367 the other knows which MIPS variant. */
368 if (compat1->the_default)
370 if (compat2->the_default)
373 /* We have no idea which one is better. This is a bug, but not
374 a critical problem; warn the user. */
375 warning (_("Selected architecture %s is ambiguous with "
376 "reported target architecture %s"),
377 selected->printable_name, from_target->printable_name);
381 /* Functions to manipulate the architecture of the target */
383 enum set_arch { set_arch_auto, set_arch_manual };
385 static const struct bfd_arch_info *target_architecture_user;
387 static const char *set_architecture_string;
390 selected_architecture_name (void)
392 if (target_architecture_user == NULL)
395 return set_architecture_string;
398 /* Called if the user enters ``show architecture'' without an
402 show_architecture (struct ui_file *file, int from_tty,
403 struct cmd_list_element *c, const char *value)
406 arch = TARGET_ARCHITECTURE->printable_name;
407 if (target_architecture_user == NULL)
408 fprintf_filtered (file, _("\
409 The target architecture is set automatically (currently %s)\n"), arch);
411 fprintf_filtered (file, _("\
412 The target architecture is assumed to be %s\n"), arch);
416 /* Called if the user enters ``set architecture'' with or without an
420 set_architecture (char *ignore_args, int from_tty, struct cmd_list_element *c)
422 struct gdbarch_info info;
424 gdbarch_info_init (&info);
426 if (strcmp (set_architecture_string, "auto") == 0)
428 target_architecture_user = NULL;
429 if (!gdbarch_update_p (info))
430 internal_error (__FILE__, __LINE__,
431 _("could not select an architecture automatically"));
435 info.bfd_arch_info = bfd_scan_arch (set_architecture_string);
436 if (info.bfd_arch_info == NULL)
437 internal_error (__FILE__, __LINE__,
438 _("set_architecture: bfd_scan_arch failed"));
439 if (gdbarch_update_p (info))
440 target_architecture_user = info.bfd_arch_info;
442 printf_unfiltered (_("Architecture `%s' not recognized.\n"),
443 set_architecture_string);
445 show_architecture (gdb_stdout, from_tty, NULL, NULL);
448 /* Try to select a global architecture that matches "info". Return
449 non-zero if the attempt succeds. */
451 gdbarch_update_p (struct gdbarch_info info)
453 struct gdbarch *new_gdbarch = gdbarch_find_by_info (info);
455 /* If there no architecture by that name, reject the request. */
456 if (new_gdbarch == NULL)
459 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
460 "Architecture not found\n");
464 /* If it is the same old architecture, accept the request (but don't
466 if (new_gdbarch == current_gdbarch)
469 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
470 "Architecture 0x%08lx (%s) unchanged\n",
472 gdbarch_bfd_arch_info (new_gdbarch)->printable_name);
476 /* It's a new architecture, swap it in. */
478 fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
479 "New architecture 0x%08lx (%s) selected\n",
481 gdbarch_bfd_arch_info (new_gdbarch)->printable_name);
482 deprecated_current_gdbarch_select_hack (new_gdbarch);
487 /* Return the architecture for ABFD. If no suitable architecture
488 could be find, return NULL. */
491 gdbarch_from_bfd (bfd *abfd)
493 struct gdbarch *old_gdbarch = current_gdbarch;
494 struct gdbarch *new_gdbarch;
495 struct gdbarch_info info;
497 /* If we call gdbarch_find_by_info without filling in info.abfd,
498 then it will use the global exec_bfd. That's fine if we don't
499 have one of those either. And that's the only time we should
500 reach here with a NULL ABFD argument - when we are discarding
502 gdb_assert (abfd != NULL || exec_bfd == NULL);
504 gdbarch_info_init (&info);
506 return gdbarch_find_by_info (info);
509 /* Set the dynamic target-system-dependent parameters (architecture,
510 byte-order) using information found in the BFD */
513 set_gdbarch_from_file (bfd *abfd)
515 struct gdbarch *gdbarch;
517 gdbarch = gdbarch_from_bfd (abfd);
519 error (_("Architecture of file not recognized."));
520 deprecated_current_gdbarch_select_hack (gdbarch);
523 /* Initialize the current architecture. Update the ``set
524 architecture'' command so that it specifies a list of valid
527 #ifdef DEFAULT_BFD_ARCH
528 extern const bfd_arch_info_type DEFAULT_BFD_ARCH;
529 static const bfd_arch_info_type *default_bfd_arch = &DEFAULT_BFD_ARCH;
531 static const bfd_arch_info_type *default_bfd_arch;
534 #ifdef DEFAULT_BFD_VEC
535 extern const bfd_target DEFAULT_BFD_VEC;
536 static const bfd_target *default_bfd_vec = &DEFAULT_BFD_VEC;
538 static const bfd_target *default_bfd_vec;
541 static int default_byte_order = BFD_ENDIAN_UNKNOWN;
544 initialize_current_architecture (void)
546 const char **arches = gdbarch_printable_names ();
548 /* determine a default architecture and byte order. */
549 struct gdbarch_info info;
550 gdbarch_info_init (&info);
552 /* Find a default architecture. */
553 if (default_bfd_arch == NULL)
555 /* Choose the architecture by taking the first one
557 const char *chosen = arches[0];
559 for (arch = arches; *arch != NULL; arch++)
561 if (strcmp (*arch, chosen) < 0)
565 internal_error (__FILE__, __LINE__,
566 _("initialize_current_architecture: No arch"));
567 default_bfd_arch = bfd_scan_arch (chosen);
568 if (default_bfd_arch == NULL)
569 internal_error (__FILE__, __LINE__,
570 _("initialize_current_architecture: Arch not found"));
573 info.bfd_arch_info = default_bfd_arch;
575 /* Take several guesses at a byte order. */
576 if (default_byte_order == BFD_ENDIAN_UNKNOWN
577 && default_bfd_vec != NULL)
579 /* Extract BFD's default vector's byte order. */
580 switch (default_bfd_vec->byteorder)
583 default_byte_order = BFD_ENDIAN_BIG;
585 case BFD_ENDIAN_LITTLE:
586 default_byte_order = BFD_ENDIAN_LITTLE;
592 if (default_byte_order == BFD_ENDIAN_UNKNOWN)
594 /* look for ``*el-*'' in the target name. */
596 chp = strchr (target_name, '-');
598 && chp - 2 >= target_name
599 && strncmp (chp - 2, "el", 2) == 0)
600 default_byte_order = BFD_ENDIAN_LITTLE;
602 if (default_byte_order == BFD_ENDIAN_UNKNOWN)
604 /* Wire it to big-endian!!! */
605 default_byte_order = BFD_ENDIAN_BIG;
608 info.byte_order = default_byte_order;
610 if (! gdbarch_update_p (info))
611 internal_error (__FILE__, __LINE__,
612 _("initialize_current_architecture: Selection of "
613 "initial architecture failed"));
615 /* Create the ``set architecture'' command appending ``auto'' to the
616 list of architectures. */
618 struct cmd_list_element *c;
619 /* Append ``auto''. */
621 for (nr = 0; arches[nr] != NULL; nr++);
622 arches = xrealloc (arches, sizeof (char*) * (nr + 2));
623 arches[nr + 0] = "auto";
624 arches[nr + 1] = NULL;
625 add_setshow_enum_cmd ("architecture", class_support,
626 arches, &set_architecture_string, _("\
627 Set architecture of target."), _("\
628 Show architecture of target."), NULL,
629 set_architecture, show_architecture,
630 &setlist, &showlist);
631 add_alias_cmd ("processor", "architecture", class_support, 1, &setlist);
636 /* Initialize a gdbarch info to values that will be automatically
637 overridden. Note: Originally, this ``struct info'' was initialized
638 using memset(0). Unfortunately, that ran into problems, namely
639 BFD_ENDIAN_BIG is zero. An explicit initialization function that
640 can explicitly set each field to a well defined value is used. */
643 gdbarch_info_init (struct gdbarch_info *info)
645 memset (info, 0, sizeof (struct gdbarch_info));
646 info->byte_order = BFD_ENDIAN_UNKNOWN;
647 info->osabi = GDB_OSABI_UNINITIALIZED;
650 /* Similar to init, but this time fill in the blanks. Information is
651 obtained from the global "set ..." options and explicitly
652 initialized INFO fields. */
655 gdbarch_info_fill (struct gdbarch_info *info)
657 /* Check for the current file. */
658 if (info->abfd == NULL)
659 info->abfd = exec_bfd;
661 /* Check for the current target description. */
662 if (info->target_desc == NULL)
663 info->target_desc = target_current_description ();
665 /* "(gdb) set architecture ...". */
666 if (info->bfd_arch_info == NULL
667 && target_architecture_user)
668 info->bfd_arch_info = target_architecture_user;
670 if (info->bfd_arch_info == NULL
671 && info->abfd != NULL
672 && bfd_get_arch (info->abfd) != bfd_arch_unknown
673 && bfd_get_arch (info->abfd) != bfd_arch_obscure)
674 info->bfd_arch_info = bfd_get_arch_info (info->abfd);
675 /* From the target. */
676 if (info->target_desc != NULL)
677 info->bfd_arch_info = choose_architecture_for_target
678 (info->bfd_arch_info, tdesc_architecture (info->target_desc));
679 /* From the default. */
680 if (info->bfd_arch_info == NULL)
681 info->bfd_arch_info = default_bfd_arch;
683 /* "(gdb) set byte-order ...". */
684 if (info->byte_order == BFD_ENDIAN_UNKNOWN
685 && target_byte_order_user != BFD_ENDIAN_UNKNOWN)
686 info->byte_order = target_byte_order_user;
687 /* From the INFO struct. */
688 if (info->byte_order == BFD_ENDIAN_UNKNOWN
689 && info->abfd != NULL)
690 info->byte_order = (bfd_big_endian (info->abfd) ? BFD_ENDIAN_BIG
691 : bfd_little_endian (info->abfd) ? BFD_ENDIAN_LITTLE
692 : BFD_ENDIAN_UNKNOWN);
693 /* From the default. */
694 if (info->byte_order == BFD_ENDIAN_UNKNOWN)
695 info->byte_order = default_byte_order;
697 /* "(gdb) set osabi ...". Handled by gdbarch_lookup_osabi. */
698 if (info->osabi == GDB_OSABI_UNINITIALIZED)
699 info->osabi = gdbarch_lookup_osabi (info->abfd);
701 /* Must have at least filled in the architecture. */
702 gdb_assert (info->bfd_arch_info != NULL);
707 extern initialize_file_ftype _initialize_gdbarch_utils; /* -Wmissing-prototypes */
710 _initialize_gdbarch_utils (void)
712 struct cmd_list_element *c;
713 add_setshow_enum_cmd ("endian", class_support,
714 endian_enum, &set_endian_string, _("\
715 Set endianness of target."), _("\
716 Show endianness of target."), NULL,
717 set_endian, show_endian,
718 &setlist, &showlist);