1 /* Dynamic architecture support for GDB, the GNU debugger.
3 Copyright (C) 1998-2014 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 #include "arch-utils.h"
25 #include "inferior.h" /* enum CALL_DUMMY_LOCATION et al. */
28 #include "sim-regno.h"
31 #include "target-descriptions.h"
37 #include "floatformat.h"
40 struct displaced_step_closure
*
41 simple_displaced_step_copy_insn (struct gdbarch
*gdbarch
,
42 CORE_ADDR from
, CORE_ADDR to
,
43 struct regcache
*regs
)
45 size_t len
= gdbarch_max_insn_length (gdbarch
);
46 gdb_byte
*buf
= xmalloc (len
);
48 read_memory (from
, buf
, len
);
49 write_memory (to
, buf
, len
);
53 fprintf_unfiltered (gdb_stdlog
, "displaced: copy %s->%s: ",
54 paddress (gdbarch
, from
), paddress (gdbarch
, to
));
55 displaced_step_dump_bytes (gdb_stdlog
, buf
, len
);
58 return (struct displaced_step_closure
*) buf
;
63 simple_displaced_step_free_closure (struct gdbarch
*gdbarch
,
64 struct displaced_step_closure
*closure
)
70 default_displaced_step_hw_singlestep (struct gdbarch
*gdbarch
,
71 struct displaced_step_closure
*closure
)
73 return !gdbarch_software_single_step_p (gdbarch
);
77 displaced_step_at_entry_point (struct gdbarch
*gdbarch
)
82 addr
= entry_point_address ();
84 /* Inferior calls also use the entry point as a breakpoint location.
85 We don't want displaced stepping to interfere with those
86 breakpoints, so leave space. */
87 gdbarch_breakpoint_from_pc (gdbarch
, &addr
, &bp_len
);
94 legacy_register_sim_regno (struct gdbarch
*gdbarch
, int regnum
)
96 /* Only makes sense to supply raw registers. */
97 gdb_assert (regnum
>= 0 && regnum
< gdbarch_num_regs (gdbarch
));
98 /* NOTE: cagney/2002-05-13: The old code did it this way and it is
99 suspected that some GDB/SIM combinations may rely on this
100 behavour. The default should be one2one_register_sim_regno
102 if (gdbarch_register_name (gdbarch
, regnum
) != NULL
103 && gdbarch_register_name (gdbarch
, regnum
)[0] != '\0')
106 return LEGACY_SIM_REGNO_IGNORE
;
110 generic_skip_trampoline_code (struct frame_info
*frame
, CORE_ADDR pc
)
116 generic_skip_solib_resolver (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
122 generic_in_solib_return_trampoline (struct gdbarch
*gdbarch
,
123 CORE_ADDR pc
, const char *name
)
129 generic_in_function_epilogue_p (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
134 /* Helper functions for gdbarch_inner_than */
137 core_addr_lessthan (CORE_ADDR lhs
, CORE_ADDR rhs
)
143 core_addr_greaterthan (CORE_ADDR lhs
, CORE_ADDR rhs
)
148 /* Misc helper functions for targets. */
151 core_addr_identity (struct gdbarch
*gdbarch
, CORE_ADDR addr
)
157 convert_from_func_ptr_addr_identity (struct gdbarch
*gdbarch
, CORE_ADDR addr
,
158 struct target_ops
*targ
)
164 no_op_reg_to_regnum (struct gdbarch
*gdbarch
, int reg
)
170 default_elf_make_msymbol_special (asymbol
*sym
, struct minimal_symbol
*msym
)
176 default_coff_make_msymbol_special (int val
, struct minimal_symbol
*msym
)
182 cannot_register_not (struct gdbarch
*gdbarch
, int regnum
)
187 /* Legacy version of target_virtual_frame_pointer(). Assumes that
188 there is an gdbarch_deprecated_fp_regnum and that it is the same,
192 legacy_virtual_frame_pointer (struct gdbarch
*gdbarch
,
195 LONGEST
*frame_offset
)
197 /* FIXME: cagney/2002-09-13: This code is used when identifying the
198 frame pointer of the current PC. It is assuming that a single
199 register and an offset can determine this. I think it should
200 instead generate a byte code expression as that would work better
201 with things like Dwarf2's CFI. */
202 if (gdbarch_deprecated_fp_regnum (gdbarch
) >= 0
203 && gdbarch_deprecated_fp_regnum (gdbarch
)
204 < gdbarch_num_regs (gdbarch
))
205 *frame_regnum
= gdbarch_deprecated_fp_regnum (gdbarch
);
206 else if (gdbarch_sp_regnum (gdbarch
) >= 0
207 && gdbarch_sp_regnum (gdbarch
)
208 < gdbarch_num_regs (gdbarch
))
209 *frame_regnum
= gdbarch_sp_regnum (gdbarch
);
211 /* Should this be an internal error? I guess so, it is reflecting
212 an architectural limitation in the current design. */
213 internal_error (__FILE__
, __LINE__
,
214 _("No virtual frame pointer available"));
220 generic_convert_register_p (struct gdbarch
*gdbarch
, int regnum
,
227 default_stabs_argument_has_addr (struct gdbarch
*gdbarch
, struct type
*type
)
233 generic_instruction_nullified (struct gdbarch
*gdbarch
,
234 struct regcache
*regcache
)
240 default_remote_register_number (struct gdbarch
*gdbarch
,
246 /* See arch-utils.h. */
249 default_vsyscall_range (struct gdbarch
*gdbarch
, struct mem_range
*range
)
255 /* Functions to manipulate the endianness of the target. */
257 static int target_byte_order_user
= BFD_ENDIAN_UNKNOWN
;
259 static const char endian_big
[] = "big";
260 static const char endian_little
[] = "little";
261 static const char endian_auto
[] = "auto";
262 static const char *const endian_enum
[] =
269 static const char *set_endian_string
;
272 selected_byte_order (void)
274 return target_byte_order_user
;
277 /* Called by ``show endian''. */
280 show_endian (struct ui_file
*file
, int from_tty
, struct cmd_list_element
*c
,
283 if (target_byte_order_user
== BFD_ENDIAN_UNKNOWN
)
284 if (gdbarch_byte_order (get_current_arch ()) == BFD_ENDIAN_BIG
)
285 fprintf_unfiltered (file
, _("The target endianness is set automatically "
286 "(currently big endian)\n"));
288 fprintf_unfiltered (file
, _("The target endianness is set automatically "
289 "(currently little endian)\n"));
291 if (target_byte_order_user
== BFD_ENDIAN_BIG
)
292 fprintf_unfiltered (file
,
293 _("The target is assumed to be big endian\n"));
295 fprintf_unfiltered (file
,
296 _("The target is assumed to be little endian\n"));
300 set_endian (char *ignore_args
, int from_tty
, struct cmd_list_element
*c
)
302 struct gdbarch_info info
;
304 gdbarch_info_init (&info
);
306 if (set_endian_string
== endian_auto
)
308 target_byte_order_user
= BFD_ENDIAN_UNKNOWN
;
309 if (! gdbarch_update_p (info
))
310 internal_error (__FILE__
, __LINE__
,
311 _("set_endian: architecture update failed"));
313 else if (set_endian_string
== endian_little
)
315 info
.byte_order
= BFD_ENDIAN_LITTLE
;
316 if (! gdbarch_update_p (info
))
317 printf_unfiltered (_("Little endian target not supported by GDB\n"));
319 target_byte_order_user
= BFD_ENDIAN_LITTLE
;
321 else if (set_endian_string
== endian_big
)
323 info
.byte_order
= BFD_ENDIAN_BIG
;
324 if (! gdbarch_update_p (info
))
325 printf_unfiltered (_("Big endian target not supported by GDB\n"));
327 target_byte_order_user
= BFD_ENDIAN_BIG
;
330 internal_error (__FILE__
, __LINE__
,
331 _("set_endian: bad value"));
333 show_endian (gdb_stdout
, from_tty
, NULL
, NULL
);
336 /* Given SELECTED, a currently selected BFD architecture, and
337 TARGET_DESC, the current target description, return what
340 SELECTED may be NULL, in which case we return the architecture
341 associated with TARGET_DESC. If SELECTED specifies a variant
342 of the architecture associtated with TARGET_DESC, return the
343 more specific of the two.
345 If SELECTED is a different architecture, but it is accepted as
346 compatible by the target, we can use the target architecture.
348 If SELECTED is obviously incompatible, warn the user. */
350 static const struct bfd_arch_info
*
351 choose_architecture_for_target (const struct target_desc
*target_desc
,
352 const struct bfd_arch_info
*selected
)
354 const struct bfd_arch_info
*from_target
= tdesc_architecture (target_desc
);
355 const struct bfd_arch_info
*compat1
, *compat2
;
357 if (selected
== NULL
)
360 if (from_target
== NULL
)
363 /* struct bfd_arch_info objects are singletons: that is, there's
364 supposed to be exactly one instance for a given machine. So you
365 can tell whether two are equivalent by comparing pointers. */
366 if (from_target
== selected
)
369 /* BFD's 'A->compatible (A, B)' functions return zero if A and B are
370 incompatible. But if they are compatible, it returns the 'more
371 featureful' of the two arches. That is, if A can run code
372 written for B, but B can't run code written for A, then it'll
375 Some targets (e.g. MIPS as of 2006-12-04) don't fully
376 implement this, instead always returning NULL or the first
377 argument. We detect that case by checking both directions. */
379 compat1
= selected
->compatible (selected
, from_target
);
380 compat2
= from_target
->compatible (from_target
, selected
);
382 if (compat1
== NULL
&& compat2
== NULL
)
384 /* BFD considers the architectures incompatible. Check our
385 target description whether it accepts SELECTED as compatible
387 if (tdesc_compatible_p (target_desc
, selected
))
390 warning (_("Selected architecture %s is not compatible "
391 "with reported target architecture %s"),
392 selected
->printable_name
, from_target
->printable_name
);
400 if (compat1
== compat2
)
403 /* If the two didn't match, but one of them was a default
404 architecture, assume the more specific one is correct. This
405 handles the case where an executable or target description just
406 says "mips", but the other knows which MIPS variant. */
407 if (compat1
->the_default
)
409 if (compat2
->the_default
)
412 /* We have no idea which one is better. This is a bug, but not
413 a critical problem; warn the user. */
414 warning (_("Selected architecture %s is ambiguous with "
415 "reported target architecture %s"),
416 selected
->printable_name
, from_target
->printable_name
);
420 /* Functions to manipulate the architecture of the target. */
422 enum set_arch
{ set_arch_auto
, set_arch_manual
};
424 static const struct bfd_arch_info
*target_architecture_user
;
426 static const char *set_architecture_string
;
429 selected_architecture_name (void)
431 if (target_architecture_user
== NULL
)
434 return set_architecture_string
;
437 /* Called if the user enters ``show architecture'' without an
441 show_architecture (struct ui_file
*file
, int from_tty
,
442 struct cmd_list_element
*c
, const char *value
)
444 if (target_architecture_user
== NULL
)
445 fprintf_filtered (file
, _("The target architecture is set "
446 "automatically (currently %s)\n"),
447 gdbarch_bfd_arch_info (get_current_arch ())->printable_name
);
449 fprintf_filtered (file
, _("The target architecture is assumed to be %s\n"),
450 set_architecture_string
);
454 /* Called if the user enters ``set architecture'' with or without an
458 set_architecture (char *ignore_args
, int from_tty
, struct cmd_list_element
*c
)
460 struct gdbarch_info info
;
462 gdbarch_info_init (&info
);
464 if (strcmp (set_architecture_string
, "auto") == 0)
466 target_architecture_user
= NULL
;
467 if (!gdbarch_update_p (info
))
468 internal_error (__FILE__
, __LINE__
,
469 _("could not select an architecture automatically"));
473 info
.bfd_arch_info
= bfd_scan_arch (set_architecture_string
);
474 if (info
.bfd_arch_info
== NULL
)
475 internal_error (__FILE__
, __LINE__
,
476 _("set_architecture: bfd_scan_arch failed"));
477 if (gdbarch_update_p (info
))
478 target_architecture_user
= info
.bfd_arch_info
;
480 printf_unfiltered (_("Architecture `%s' not recognized.\n"),
481 set_architecture_string
);
483 show_architecture (gdb_stdout
, from_tty
, NULL
, NULL
);
486 /* Try to select a global architecture that matches "info". Return
487 non-zero if the attempt succeeds. */
489 gdbarch_update_p (struct gdbarch_info info
)
491 struct gdbarch
*new_gdbarch
;
493 /* Check for the current file. */
494 if (info
.abfd
== NULL
)
495 info
.abfd
= exec_bfd
;
496 if (info
.abfd
== NULL
)
497 info
.abfd
= core_bfd
;
499 /* Check for the current target description. */
500 if (info
.target_desc
== NULL
)
501 info
.target_desc
= target_current_description ();
503 new_gdbarch
= gdbarch_find_by_info (info
);
505 /* If there no architecture by that name, reject the request. */
506 if (new_gdbarch
== NULL
)
509 fprintf_unfiltered (gdb_stdlog
, "gdbarch_update_p: "
510 "Architecture not found\n");
514 /* If it is the same old architecture, accept the request (but don't
516 if (new_gdbarch
== target_gdbarch ())
519 fprintf_unfiltered (gdb_stdlog
, "gdbarch_update_p: "
520 "Architecture %s (%s) unchanged\n",
521 host_address_to_string (new_gdbarch
),
522 gdbarch_bfd_arch_info (new_gdbarch
)->printable_name
);
526 /* It's a new architecture, swap it in. */
528 fprintf_unfiltered (gdb_stdlog
, "gdbarch_update_p: "
529 "New architecture %s (%s) selected\n",
530 host_address_to_string (new_gdbarch
),
531 gdbarch_bfd_arch_info (new_gdbarch
)->printable_name
);
532 set_target_gdbarch (new_gdbarch
);
537 /* Return the architecture for ABFD. If no suitable architecture
538 could be find, return NULL. */
541 gdbarch_from_bfd (bfd
*abfd
)
543 struct gdbarch_info info
;
544 gdbarch_info_init (&info
);
547 return gdbarch_find_by_info (info
);
550 /* Set the dynamic target-system-dependent parameters (architecture,
551 byte-order) using information found in the BFD */
554 set_gdbarch_from_file (bfd
*abfd
)
556 struct gdbarch_info info
;
557 struct gdbarch
*gdbarch
;
559 gdbarch_info_init (&info
);
561 info
.target_desc
= target_current_description ();
562 gdbarch
= gdbarch_find_by_info (info
);
565 error (_("Architecture of file not recognized."));
566 set_target_gdbarch (gdbarch
);
569 /* Initialize the current architecture. Update the ``set
570 architecture'' command so that it specifies a list of valid
573 #ifdef DEFAULT_BFD_ARCH
574 extern const bfd_arch_info_type DEFAULT_BFD_ARCH
;
575 static const bfd_arch_info_type
*default_bfd_arch
= &DEFAULT_BFD_ARCH
;
577 static const bfd_arch_info_type
*default_bfd_arch
;
580 #ifdef DEFAULT_BFD_VEC
581 extern const bfd_target DEFAULT_BFD_VEC
;
582 static const bfd_target
*default_bfd_vec
= &DEFAULT_BFD_VEC
;
584 static const bfd_target
*default_bfd_vec
;
587 static int default_byte_order
= BFD_ENDIAN_UNKNOWN
;
590 initialize_current_architecture (void)
592 const char **arches
= gdbarch_printable_names ();
593 struct gdbarch_info info
;
595 /* determine a default architecture and byte order. */
596 gdbarch_info_init (&info
);
598 /* Find a default architecture. */
599 if (default_bfd_arch
== NULL
)
601 /* Choose the architecture by taking the first one
603 const char *chosen
= arches
[0];
605 for (arch
= arches
; *arch
!= NULL
; arch
++)
607 if (strcmp (*arch
, chosen
) < 0)
611 internal_error (__FILE__
, __LINE__
,
612 _("initialize_current_architecture: No arch"));
613 default_bfd_arch
= bfd_scan_arch (chosen
);
614 if (default_bfd_arch
== NULL
)
615 internal_error (__FILE__
, __LINE__
,
616 _("initialize_current_architecture: Arch not found"));
619 info
.bfd_arch_info
= default_bfd_arch
;
621 /* Take several guesses at a byte order. */
622 if (default_byte_order
== BFD_ENDIAN_UNKNOWN
623 && default_bfd_vec
!= NULL
)
625 /* Extract BFD's default vector's byte order. */
626 switch (default_bfd_vec
->byteorder
)
629 default_byte_order
= BFD_ENDIAN_BIG
;
631 case BFD_ENDIAN_LITTLE
:
632 default_byte_order
= BFD_ENDIAN_LITTLE
;
638 if (default_byte_order
== BFD_ENDIAN_UNKNOWN
)
640 /* look for ``*el-*'' in the target name. */
642 chp
= strchr (target_name
, '-');
644 && chp
- 2 >= target_name
645 && strncmp (chp
- 2, "el", 2) == 0)
646 default_byte_order
= BFD_ENDIAN_LITTLE
;
648 if (default_byte_order
== BFD_ENDIAN_UNKNOWN
)
650 /* Wire it to big-endian!!! */
651 default_byte_order
= BFD_ENDIAN_BIG
;
654 info
.byte_order
= default_byte_order
;
655 info
.byte_order_for_code
= info
.byte_order
;
657 if (! gdbarch_update_p (info
))
658 internal_error (__FILE__
, __LINE__
,
659 _("initialize_current_architecture: Selection of "
660 "initial architecture failed"));
662 /* Create the ``set architecture'' command appending ``auto'' to the
663 list of architectures. */
665 /* Append ``auto''. */
667 for (nr
= 0; arches
[nr
] != NULL
; nr
++);
668 arches
= xrealloc (arches
, sizeof (char*) * (nr
+ 2));
669 arches
[nr
+ 0] = "auto";
670 arches
[nr
+ 1] = NULL
;
671 add_setshow_enum_cmd ("architecture", class_support
,
672 arches
, &set_architecture_string
,
673 _("Set architecture of target."),
674 _("Show architecture of target."), NULL
,
675 set_architecture
, show_architecture
,
676 &setlist
, &showlist
);
677 add_alias_cmd ("processor", "architecture", class_support
, 1, &setlist
);
682 /* Initialize a gdbarch info to values that will be automatically
683 overridden. Note: Originally, this ``struct info'' was initialized
684 using memset(0). Unfortunately, that ran into problems, namely
685 BFD_ENDIAN_BIG is zero. An explicit initialization function that
686 can explicitly set each field to a well defined value is used. */
689 gdbarch_info_init (struct gdbarch_info
*info
)
691 memset (info
, 0, sizeof (struct gdbarch_info
));
692 info
->byte_order
= BFD_ENDIAN_UNKNOWN
;
693 info
->byte_order_for_code
= info
->byte_order
;
694 info
->osabi
= GDB_OSABI_UNINITIALIZED
;
697 /* Similar to init, but this time fill in the blanks. Information is
698 obtained from the global "set ..." options and explicitly
699 initialized INFO fields. */
702 gdbarch_info_fill (struct gdbarch_info
*info
)
704 /* "(gdb) set architecture ...". */
705 if (info
->bfd_arch_info
== NULL
706 && target_architecture_user
)
707 info
->bfd_arch_info
= target_architecture_user
;
709 if (info
->bfd_arch_info
== NULL
710 && info
->abfd
!= NULL
711 && bfd_get_arch (info
->abfd
) != bfd_arch_unknown
712 && bfd_get_arch (info
->abfd
) != bfd_arch_obscure
)
713 info
->bfd_arch_info
= bfd_get_arch_info (info
->abfd
);
714 /* From the target. */
715 if (info
->target_desc
!= NULL
)
716 info
->bfd_arch_info
= choose_architecture_for_target
717 (info
->target_desc
, info
->bfd_arch_info
);
718 /* From the default. */
719 if (info
->bfd_arch_info
== NULL
)
720 info
->bfd_arch_info
= default_bfd_arch
;
722 /* "(gdb) set byte-order ...". */
723 if (info
->byte_order
== BFD_ENDIAN_UNKNOWN
724 && target_byte_order_user
!= BFD_ENDIAN_UNKNOWN
)
725 info
->byte_order
= target_byte_order_user
;
726 /* From the INFO struct. */
727 if (info
->byte_order
== BFD_ENDIAN_UNKNOWN
728 && info
->abfd
!= NULL
)
729 info
->byte_order
= (bfd_big_endian (info
->abfd
) ? BFD_ENDIAN_BIG
730 : bfd_little_endian (info
->abfd
) ? BFD_ENDIAN_LITTLE
731 : BFD_ENDIAN_UNKNOWN
);
732 /* From the default. */
733 if (info
->byte_order
== BFD_ENDIAN_UNKNOWN
)
734 info
->byte_order
= default_byte_order
;
735 info
->byte_order_for_code
= info
->byte_order
;
737 /* "(gdb) set osabi ...". Handled by gdbarch_lookup_osabi. */
738 /* From the manual override, or from file. */
739 if (info
->osabi
== GDB_OSABI_UNINITIALIZED
)
740 info
->osabi
= gdbarch_lookup_osabi (info
->abfd
);
741 /* From the target. */
742 if (info
->osabi
== GDB_OSABI_UNKNOWN
&& info
->target_desc
!= NULL
)
743 info
->osabi
= tdesc_osabi (info
->target_desc
);
744 /* From the configured default. */
745 #ifdef GDB_OSABI_DEFAULT
746 if (info
->osabi
== GDB_OSABI_UNKNOWN
)
747 info
->osabi
= GDB_OSABI_DEFAULT
;
750 /* Must have at least filled in the architecture. */
751 gdb_assert (info
->bfd_arch_info
!= NULL
);
754 /* Return "current" architecture. If the target is running, this is
755 the architecture of the selected frame. Otherwise, the "current"
756 architecture defaults to the target architecture.
758 This function should normally be called solely by the command
759 interpreter routines to determine the architecture to execute a
762 get_current_arch (void)
764 if (has_stack_frames ())
765 return get_frame_arch (get_selected_frame (NULL
));
767 return target_gdbarch ();
771 default_has_shared_address_space (struct gdbarch
*gdbarch
)
773 /* Simply say no. In most unix-like targets each inferior/process
774 has its own address space. */
779 default_fast_tracepoint_valid_at (struct gdbarch
*gdbarch
,
780 CORE_ADDR addr
, int *isize
, char **msg
)
782 /* We don't know if maybe the target has some way to do fast
783 tracepoints that doesn't need gdbarch, so always say yes. */
790 default_remote_breakpoint_from_pc (struct gdbarch
*gdbarch
, CORE_ADDR
*pcptr
,
793 gdbarch_breakpoint_from_pc (gdbarch
, pcptr
, kindptr
);
797 default_gen_return_address (struct gdbarch
*gdbarch
,
798 struct agent_expr
*ax
, struct axs_value
*value
,
801 error (_("This architecture has no method to collect a return address."));
805 default_return_in_first_hidden_param_p (struct gdbarch
*gdbarch
,
808 /* Usually, the return value's address is stored the in the "first hidden"
809 parameter if the return value should be passed by reference, as
811 return language_pass_by_reference (type
);
814 int default_insn_is_call (struct gdbarch
*gdbarch
, CORE_ADDR addr
)
819 int default_insn_is_ret (struct gdbarch
*gdbarch
, CORE_ADDR addr
)
824 int default_insn_is_jump (struct gdbarch
*gdbarch
, CORE_ADDR addr
)
831 /* -Wmissing-prototypes */
832 extern initialize_file_ftype _initialize_gdbarch_utils
;
835 _initialize_gdbarch_utils (void)
837 add_setshow_enum_cmd ("endian", class_support
,
838 endian_enum
, &set_endian_string
,
839 _("Set endianness of target."),
840 _("Show endianness of target."),
841 NULL
, set_endian
, show_endian
,
842 &setlist
, &showlist
);