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d4c16835ca
This adds support for comand options to the "backtrace" command. We'll get: (gdb) bt - -entry-values -hide -past-main -frame-arguments -no-filters -raw-frame-arguments -full -past-entry ~~~~ (gdb) help backtrace Print backtrace of all stack frames, or innermost COUNT frames. Usage: backtrace [OPTION]... [QUALIFIER]... [COUNT | -COUNT] Options: -entry-values no|only|preferred|if-needed|both|compact|default Set printing of function arguments at function entry GDB can sometimes determine the values of function arguments at entry, in addition to their current values. This option tells GDB whether to print the current value, the value at entry (marked as val@entry), or both. Note that one or both of these values may be <optimized out>. -frame-arguments all|scalars|none Set printing of non-scalar frame arguments -raw-frame-arguments [on|off] Set whether to print frame arguments in raw form. If set, frame arguments are printed in raw form, bypassing any pretty-printers for that value. -past-main [on|off] Set whether backtraces should continue past "main". Normally the caller of "main" is not of interest, so GDB will terminate the backtrace at "main". Set this if you need to see the rest of the stack trace. -past-entry [on|off] Set whether backtraces should continue past the entry point of a program. Normally there are no callers beyond the entry point of a program, so GDB will terminate the backtrace there. Set this if you need to see the rest of the stack trace. -full Print values of local variables. -no-filters Prohibit frame filters from executing on a backtrace. -hide Causes Python frame filter elided frames to not be printed. For backward compatibility, the following qualifiers are supported: full - same as -full option. no-filters - same as -no-filters option. hide - same as -hide. With a negative COUNT, print outermost -COUNT frames. ~~~~ Implementation wise, this: - Moves relevant options/settings globals to structures. - Tweaks a number of functions to pass down references to such structures. - Adds option_def structures describing the options/settings. - Makes backtrace_command parse the options, with gdb::option::process_options. - Tweaks "backtrace"'s help to describe the new options. - Adds testcases. Note that backtrace is a PROCESS_OPTIONS_UNKNOWN_IS_OPERAND command, because of the "-COUNT" argument. The COUNT/-COUNT argument is currently parsed as an expression. I considered whether it would be prudent here to require "--", but concluded that the risk of causing a significant breakage here is much lower compared to "print", since printing the expression is not the whole point of the "backtrace" command. Seems OK to me to require typing "backtrace -past-main -- -p" if the user truly wants to refer to the negative of a backtrace count stored in an inferior variable called "p". gdb/ChangeLog: 2019-06-13 Pedro Alves <palves@redhat.com> * frame.c: Include "cli/cli-option.h. (user_set_backtrace_options): New. (backtrace_past_main, backtrace_past_entry, backtrace_limit): Delete. (get_prev_frame): Adjust. (boolean_option_def, uinteger_option_def) (set_backtrace_option_defs): New. (_initialize_frame): Adjust and use gdb::option::add_setshow_cmds_for_options to install "set backtrace past-main" and "set backtrace past-entry". * frame.h: Include "cli/cli-option.h". (struct frame_print_options): Forward declare. (print_frame_arguments_all, print_frame_arguments_scalars) (print_frame_arguments_none): Declare. (print_entry_values): Delete declaration. (struct frame_print_options, user_frame_print_options): New. (struct set_backtrace_options): New. (set_backtrace_option_defs, user_set_backtrace_options): Declare. * mi/mi-cmd-stack.c (mi_cmd_stack_list_frames) (mi_cmd_stack_list_locals, mi_cmd_stack_list_args) (mi_cmd_stack_list_variables): Pass down USER_FRAME_PRINT_OPTIONS. (list_args_or_locals): Add frame_print_options parameter. (mi_cmd_stack_info_frame): Pass down USER_FRAME_PRINT_OPTIONS. * python/py-framefilter.c (enumerate_args): Pass down USER_FRAME_PRINT_OPTIONS. * stack.c: Include "cli/cli-option.h". (print_frame_arguments_all, print_frame_arguments_scalars) (print_frame_arguments_none): Declare. (print_raw_frame_arguments, print_entry_values): Delete. (user_frame_print_options): New. (boolean_option_def, enum_option_def, frame_print_option_defs): New. (struct backtrace_cmd_options): New. (bt_flag_option_def): New. (backtrace_command_option_defs): New. (print_stack_frame): Pass down USER_FRAME_PRINT_OPTIONS. (print_frame_arg, read_frame_arg, print_frame_args) (print_frame_info, print_frame): Add frame_print_options parameter and use it. (info_frame_command_core): Pass down USER_FRAME_PRINT_OPTIONS. (backtrace_command_1): Add frame_print_options and backtrace_cmd_options parameters and use them. (make_backtrace_options_def_group): New. (backtrace_command): Process command options with gdb::option::process_options. (backtrace_command_completer): New. (_initialize_stack): Extend "backtrace"'s help to mention supported options. Install completer for "backtrace". Install some settings commands with add_setshow_cmds_for_options. gdb/testsuite/ChangeLog: 2019-06-13 Pedro Alves <palves@redhat.com> * gdb.base/options.exp (test-backtrace): New. (top level): Call it.
2981 lines
88 KiB
C
2981 lines
88 KiB
C
/* Cache and manage frames for GDB, the GNU debugger.
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Copyright (C) 1986-2019 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include "defs.h"
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#include "frame.h"
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#include "target.h"
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#include "value.h"
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#include "inferior.h" /* for inferior_ptid */
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#include "regcache.h"
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#include "user-regs.h"
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#include "gdb_obstack.h"
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#include "dummy-frame.h"
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#include "sentinel-frame.h"
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#include "gdbcore.h"
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#include "annotate.h"
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#include "language.h"
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#include "frame-unwind.h"
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#include "frame-base.h"
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#include "command.h"
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#include "gdbcmd.h"
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#include "observable.h"
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#include "objfiles.h"
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#include "gdbthread.h"
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#include "block.h"
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#include "inline-frame.h"
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#include "tracepoint.h"
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#include "hashtab.h"
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#include "valprint.h"
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#include "cli/cli-option.h"
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/* The sentinel frame terminates the innermost end of the frame chain.
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If unwound, it returns the information needed to construct an
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innermost frame.
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The current frame, which is the innermost frame, can be found at
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sentinel_frame->prev. */
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static struct frame_info *sentinel_frame;
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/* The values behind the global "set backtrace ..." settings. */
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set_backtrace_options user_set_backtrace_options;
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static struct frame_info *get_prev_frame_raw (struct frame_info *this_frame);
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static const char *frame_stop_reason_symbol_string (enum unwind_stop_reason reason);
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/* Status of some values cached in the frame_info object. */
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enum cached_copy_status
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{
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/* Value is unknown. */
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CC_UNKNOWN,
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/* We have a value. */
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CC_VALUE,
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/* Value was not saved. */
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CC_NOT_SAVED,
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/* Value is unavailable. */
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CC_UNAVAILABLE
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};
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/* We keep a cache of stack frames, each of which is a "struct
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frame_info". The innermost one gets allocated (in
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wait_for_inferior) each time the inferior stops; sentinel_frame
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points to it. Additional frames get allocated (in get_prev_frame)
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as needed, and are chained through the next and prev fields. Any
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time that the frame cache becomes invalid (most notably when we
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execute something, but also if we change how we interpret the
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frames (e.g. "set heuristic-fence-post" in mips-tdep.c, or anything
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which reads new symbols)), we should call reinit_frame_cache. */
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struct frame_info
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{
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/* Level of this frame. The inner-most (youngest) frame is at level
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0. As you move towards the outer-most (oldest) frame, the level
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increases. This is a cached value. It could just as easily be
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computed by counting back from the selected frame to the inner
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most frame. */
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/* NOTE: cagney/2002-04-05: Perhaps a level of ``-1'' should be
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reserved to indicate a bogus frame - one that has been created
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just to keep GDB happy (GDB always needs a frame). For the
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moment leave this as speculation. */
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int level;
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/* The frame's program space. */
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struct program_space *pspace;
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/* The frame's address space. */
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const address_space *aspace;
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/* The frame's low-level unwinder and corresponding cache. The
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low-level unwinder is responsible for unwinding register values
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for the previous frame. The low-level unwind methods are
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selected based on the presence, or otherwise, of register unwind
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information such as CFI. */
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void *prologue_cache;
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const struct frame_unwind *unwind;
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/* Cached copy of the previous frame's architecture. */
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struct
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{
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int p;
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struct gdbarch *arch;
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} prev_arch;
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/* Cached copy of the previous frame's resume address. */
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struct {
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enum cached_copy_status status;
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CORE_ADDR value;
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} prev_pc;
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/* Cached copy of the previous frame's function address. */
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struct
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{
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CORE_ADDR addr;
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int p;
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} prev_func;
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/* This frame's ID. */
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struct
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{
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int p;
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struct frame_id value;
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} this_id;
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/* The frame's high-level base methods, and corresponding cache.
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The high level base methods are selected based on the frame's
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debug info. */
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const struct frame_base *base;
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void *base_cache;
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/* Pointers to the next (down, inner, younger) and previous (up,
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outer, older) frame_info's in the frame cache. */
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struct frame_info *next; /* down, inner, younger */
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int prev_p;
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struct frame_info *prev; /* up, outer, older */
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/* The reason why we could not set PREV, or UNWIND_NO_REASON if we
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could. Only valid when PREV_P is set. */
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enum unwind_stop_reason stop_reason;
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/* A frame specific string describing the STOP_REASON in more detail.
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Only valid when PREV_P is set, but even then may still be NULL. */
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const char *stop_string;
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};
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/* A frame stash used to speed up frame lookups. Create a hash table
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to stash frames previously accessed from the frame cache for
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quicker subsequent retrieval. The hash table is emptied whenever
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the frame cache is invalidated. */
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static htab_t frame_stash;
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/* Internal function to calculate a hash from the frame_id addresses,
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using as many valid addresses as possible. Frames below level 0
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are not stored in the hash table. */
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static hashval_t
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frame_addr_hash (const void *ap)
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{
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const struct frame_info *frame = (const struct frame_info *) ap;
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const struct frame_id f_id = frame->this_id.value;
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hashval_t hash = 0;
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gdb_assert (f_id.stack_status != FID_STACK_INVALID
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|| f_id.code_addr_p
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|| f_id.special_addr_p);
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if (f_id.stack_status == FID_STACK_VALID)
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hash = iterative_hash (&f_id.stack_addr,
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sizeof (f_id.stack_addr), hash);
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if (f_id.code_addr_p)
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hash = iterative_hash (&f_id.code_addr,
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sizeof (f_id.code_addr), hash);
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if (f_id.special_addr_p)
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hash = iterative_hash (&f_id.special_addr,
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sizeof (f_id.special_addr), hash);
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return hash;
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}
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/* Internal equality function for the hash table. This function
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defers equality operations to frame_id_eq. */
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static int
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frame_addr_hash_eq (const void *a, const void *b)
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{
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const struct frame_info *f_entry = (const struct frame_info *) a;
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const struct frame_info *f_element = (const struct frame_info *) b;
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return frame_id_eq (f_entry->this_id.value,
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f_element->this_id.value);
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}
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/* Internal function to create the frame_stash hash table. 100 seems
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to be a good compromise to start the hash table at. */
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static void
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frame_stash_create (void)
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{
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frame_stash = htab_create (100,
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frame_addr_hash,
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frame_addr_hash_eq,
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NULL);
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}
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/* Internal function to add a frame to the frame_stash hash table.
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Returns false if a frame with the same ID was already stashed, true
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otherwise. */
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static int
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frame_stash_add (struct frame_info *frame)
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{
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struct frame_info **slot;
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/* Do not try to stash the sentinel frame. */
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gdb_assert (frame->level >= 0);
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slot = (struct frame_info **) htab_find_slot (frame_stash,
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frame,
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INSERT);
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/* If we already have a frame in the stack with the same id, we
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either have a stack cycle (corrupted stack?), or some bug
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elsewhere in GDB. In any case, ignore the duplicate and return
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an indication to the caller. */
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if (*slot != NULL)
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return 0;
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*slot = frame;
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return 1;
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}
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/* Internal function to search the frame stash for an entry with the
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given frame ID. If found, return that frame. Otherwise return
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NULL. */
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static struct frame_info *
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frame_stash_find (struct frame_id id)
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{
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struct frame_info dummy;
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struct frame_info *frame;
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dummy.this_id.value = id;
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frame = (struct frame_info *) htab_find (frame_stash, &dummy);
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return frame;
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}
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/* Internal function to invalidate the frame stash by removing all
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entries in it. This only occurs when the frame cache is
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invalidated. */
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static void
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frame_stash_invalidate (void)
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{
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htab_empty (frame_stash);
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}
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/* See frame.h */
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scoped_restore_selected_frame::scoped_restore_selected_frame ()
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{
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m_fid = get_frame_id (get_selected_frame (NULL));
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}
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/* See frame.h */
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scoped_restore_selected_frame::~scoped_restore_selected_frame ()
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{
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frame_info *frame = frame_find_by_id (m_fid);
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if (frame == NULL)
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warning (_("Unable to restore previously selected frame."));
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else
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select_frame (frame);
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}
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/* Flag to control debugging. */
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unsigned int frame_debug;
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static void
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show_frame_debug (struct ui_file *file, int from_tty,
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struct cmd_list_element *c, const char *value)
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{
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fprintf_filtered (file, _("Frame debugging is %s.\n"), value);
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}
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/* Implementation of "show backtrace past-main". */
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static void
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show_backtrace_past_main (struct ui_file *file, int from_tty,
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struct cmd_list_element *c, const char *value)
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{
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fprintf_filtered (file,
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_("Whether backtraces should "
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"continue past \"main\" is %s.\n"),
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value);
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}
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/* Implementation of "show backtrace past-entry". */
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static void
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show_backtrace_past_entry (struct ui_file *file, int from_tty,
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struct cmd_list_element *c, const char *value)
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{
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fprintf_filtered (file, _("Whether backtraces should continue past the "
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"entry point of a program is %s.\n"),
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value);
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}
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/* Implementation of "show backtrace limit". */
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static void
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show_backtrace_limit (struct ui_file *file, int from_tty,
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struct cmd_list_element *c, const char *value)
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{
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fprintf_filtered (file,
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_("An upper bound on the number "
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"of backtrace levels is %s.\n"),
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value);
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}
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static void
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fprint_field (struct ui_file *file, const char *name, int p, CORE_ADDR addr)
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{
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if (p)
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fprintf_unfiltered (file, "%s=%s", name, hex_string (addr));
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else
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fprintf_unfiltered (file, "!%s", name);
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}
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void
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fprint_frame_id (struct ui_file *file, struct frame_id id)
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{
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fprintf_unfiltered (file, "{");
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if (id.stack_status == FID_STACK_INVALID)
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fprintf_unfiltered (file, "!stack");
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else if (id.stack_status == FID_STACK_UNAVAILABLE)
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fprintf_unfiltered (file, "stack=<unavailable>");
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else if (id.stack_status == FID_STACK_SENTINEL)
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fprintf_unfiltered (file, "stack=<sentinel>");
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else
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fprintf_unfiltered (file, "stack=%s", hex_string (id.stack_addr));
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fprintf_unfiltered (file, ",");
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fprint_field (file, "code", id.code_addr_p, id.code_addr);
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fprintf_unfiltered (file, ",");
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fprint_field (file, "special", id.special_addr_p, id.special_addr);
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if (id.artificial_depth)
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fprintf_unfiltered (file, ",artificial=%d", id.artificial_depth);
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fprintf_unfiltered (file, "}");
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}
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static void
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fprint_frame_type (struct ui_file *file, enum frame_type type)
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{
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switch (type)
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{
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case NORMAL_FRAME:
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fprintf_unfiltered (file, "NORMAL_FRAME");
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return;
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case DUMMY_FRAME:
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fprintf_unfiltered (file, "DUMMY_FRAME");
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return;
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case INLINE_FRAME:
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fprintf_unfiltered (file, "INLINE_FRAME");
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return;
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case TAILCALL_FRAME:
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fprintf_unfiltered (file, "TAILCALL_FRAME");
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return;
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case SIGTRAMP_FRAME:
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fprintf_unfiltered (file, "SIGTRAMP_FRAME");
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return;
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case ARCH_FRAME:
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fprintf_unfiltered (file, "ARCH_FRAME");
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return;
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case SENTINEL_FRAME:
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fprintf_unfiltered (file, "SENTINEL_FRAME");
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return;
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default:
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fprintf_unfiltered (file, "<unknown type>");
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return;
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};
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}
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static void
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fprint_frame (struct ui_file *file, struct frame_info *fi)
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{
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if (fi == NULL)
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{
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fprintf_unfiltered (file, "<NULL frame>");
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return;
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}
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fprintf_unfiltered (file, "{");
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fprintf_unfiltered (file, "level=%d", fi->level);
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fprintf_unfiltered (file, ",");
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fprintf_unfiltered (file, "type=");
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if (fi->unwind != NULL)
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fprint_frame_type (file, fi->unwind->type);
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else
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fprintf_unfiltered (file, "<unknown>");
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fprintf_unfiltered (file, ",");
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fprintf_unfiltered (file, "unwind=");
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if (fi->unwind != NULL)
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gdb_print_host_address (fi->unwind, file);
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else
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fprintf_unfiltered (file, "<unknown>");
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fprintf_unfiltered (file, ",");
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fprintf_unfiltered (file, "pc=");
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if (fi->next == NULL || fi->next->prev_pc.status == CC_UNKNOWN)
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fprintf_unfiltered (file, "<unknown>");
|
|
else if (fi->next->prev_pc.status == CC_VALUE)
|
|
fprintf_unfiltered (file, "%s",
|
|
hex_string (fi->next->prev_pc.value));
|
|
else if (fi->next->prev_pc.status == CC_NOT_SAVED)
|
|
val_print_not_saved (file);
|
|
else if (fi->next->prev_pc.status == CC_UNAVAILABLE)
|
|
val_print_unavailable (file);
|
|
fprintf_unfiltered (file, ",");
|
|
fprintf_unfiltered (file, "id=");
|
|
if (fi->this_id.p)
|
|
fprint_frame_id (file, fi->this_id.value);
|
|
else
|
|
fprintf_unfiltered (file, "<unknown>");
|
|
fprintf_unfiltered (file, ",");
|
|
fprintf_unfiltered (file, "func=");
|
|
if (fi->next != NULL && fi->next->prev_func.p)
|
|
fprintf_unfiltered (file, "%s", hex_string (fi->next->prev_func.addr));
|
|
else
|
|
fprintf_unfiltered (file, "<unknown>");
|
|
fprintf_unfiltered (file, "}");
|
|
}
|
|
|
|
/* Given FRAME, return the enclosing frame as found in real frames read-in from
|
|
inferior memory. Skip any previous frames which were made up by GDB.
|
|
Return FRAME if FRAME is a non-artificial frame.
|
|
Return NULL if FRAME is the start of an artificial-only chain. */
|
|
|
|
static struct frame_info *
|
|
skip_artificial_frames (struct frame_info *frame)
|
|
{
|
|
/* Note we use get_prev_frame_always, and not get_prev_frame. The
|
|
latter will truncate the frame chain, leading to this function
|
|
unintentionally returning a null_frame_id (e.g., when the user
|
|
sets a backtrace limit).
|
|
|
|
Note that for record targets we may get a frame chain that consists
|
|
of artificial frames only. */
|
|
while (get_frame_type (frame) == INLINE_FRAME
|
|
|| get_frame_type (frame) == TAILCALL_FRAME)
|
|
{
|
|
frame = get_prev_frame_always (frame);
|
|
if (frame == NULL)
|
|
break;
|
|
}
|
|
|
|
return frame;
|
|
}
|
|
|
|
struct frame_info *
|
|
skip_unwritable_frames (struct frame_info *frame)
|
|
{
|
|
while (gdbarch_code_of_frame_writable (get_frame_arch (frame), frame) == 0)
|
|
{
|
|
frame = get_prev_frame (frame);
|
|
if (frame == NULL)
|
|
break;
|
|
}
|
|
|
|
return frame;
|
|
}
|
|
|
|
/* See frame.h. */
|
|
|
|
struct frame_info *
|
|
skip_tailcall_frames (struct frame_info *frame)
|
|
{
|
|
while (get_frame_type (frame) == TAILCALL_FRAME)
|
|
{
|
|
/* Note that for record targets we may get a frame chain that consists of
|
|
tailcall frames only. */
|
|
frame = get_prev_frame (frame);
|
|
if (frame == NULL)
|
|
break;
|
|
}
|
|
|
|
return frame;
|
|
}
|
|
|
|
/* Compute the frame's uniq ID that can be used to, later, re-find the
|
|
frame. */
|
|
|
|
static void
|
|
compute_frame_id (struct frame_info *fi)
|
|
{
|
|
gdb_assert (!fi->this_id.p);
|
|
|
|
if (frame_debug)
|
|
fprintf_unfiltered (gdb_stdlog, "{ compute_frame_id (fi=%d) ",
|
|
fi->level);
|
|
/* Find the unwinder. */
|
|
if (fi->unwind == NULL)
|
|
frame_unwind_find_by_frame (fi, &fi->prologue_cache);
|
|
/* Find THIS frame's ID. */
|
|
/* Default to outermost if no ID is found. */
|
|
fi->this_id.value = outer_frame_id;
|
|
fi->unwind->this_id (fi, &fi->prologue_cache, &fi->this_id.value);
|
|
gdb_assert (frame_id_p (fi->this_id.value));
|
|
fi->this_id.p = 1;
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "-> ");
|
|
fprint_frame_id (gdb_stdlog, fi->this_id.value);
|
|
fprintf_unfiltered (gdb_stdlog, " }\n");
|
|
}
|
|
}
|
|
|
|
/* Return a frame uniq ID that can be used to, later, re-find the
|
|
frame. */
|
|
|
|
struct frame_id
|
|
get_frame_id (struct frame_info *fi)
|
|
{
|
|
if (fi == NULL)
|
|
return null_frame_id;
|
|
|
|
if (!fi->this_id.p)
|
|
{
|
|
int stashed;
|
|
|
|
/* If we haven't computed the frame id yet, then it must be that
|
|
this is the current frame. Compute it now, and stash the
|
|
result. The IDs of other frames are computed as soon as
|
|
they're created, in order to detect cycles. See
|
|
get_prev_frame_if_no_cycle. */
|
|
gdb_assert (fi->level == 0);
|
|
|
|
/* Compute. */
|
|
compute_frame_id (fi);
|
|
|
|
/* Since this is the first frame in the chain, this should
|
|
always succeed. */
|
|
stashed = frame_stash_add (fi);
|
|
gdb_assert (stashed);
|
|
}
|
|
|
|
return fi->this_id.value;
|
|
}
|
|
|
|
struct frame_id
|
|
get_stack_frame_id (struct frame_info *next_frame)
|
|
{
|
|
return get_frame_id (skip_artificial_frames (next_frame));
|
|
}
|
|
|
|
struct frame_id
|
|
frame_unwind_caller_id (struct frame_info *next_frame)
|
|
{
|
|
struct frame_info *this_frame;
|
|
|
|
/* Use get_prev_frame_always, and not get_prev_frame. The latter
|
|
will truncate the frame chain, leading to this function
|
|
unintentionally returning a null_frame_id (e.g., when a caller
|
|
requests the frame ID of "main()"s caller. */
|
|
|
|
next_frame = skip_artificial_frames (next_frame);
|
|
if (next_frame == NULL)
|
|
return null_frame_id;
|
|
|
|
this_frame = get_prev_frame_always (next_frame);
|
|
if (this_frame)
|
|
return get_frame_id (skip_artificial_frames (this_frame));
|
|
else
|
|
return null_frame_id;
|
|
}
|
|
|
|
const struct frame_id null_frame_id = { 0 }; /* All zeros. */
|
|
const struct frame_id sentinel_frame_id = { 0, 0, 0, FID_STACK_SENTINEL, 0, 1, 0 };
|
|
const struct frame_id outer_frame_id = { 0, 0, 0, FID_STACK_INVALID, 0, 1, 0 };
|
|
|
|
struct frame_id
|
|
frame_id_build_special (CORE_ADDR stack_addr, CORE_ADDR code_addr,
|
|
CORE_ADDR special_addr)
|
|
{
|
|
struct frame_id id = null_frame_id;
|
|
|
|
id.stack_addr = stack_addr;
|
|
id.stack_status = FID_STACK_VALID;
|
|
id.code_addr = code_addr;
|
|
id.code_addr_p = 1;
|
|
id.special_addr = special_addr;
|
|
id.special_addr_p = 1;
|
|
return id;
|
|
}
|
|
|
|
/* See frame.h. */
|
|
|
|
struct frame_id
|
|
frame_id_build_unavailable_stack (CORE_ADDR code_addr)
|
|
{
|
|
struct frame_id id = null_frame_id;
|
|
|
|
id.stack_status = FID_STACK_UNAVAILABLE;
|
|
id.code_addr = code_addr;
|
|
id.code_addr_p = 1;
|
|
return id;
|
|
}
|
|
|
|
/* See frame.h. */
|
|
|
|
struct frame_id
|
|
frame_id_build_unavailable_stack_special (CORE_ADDR code_addr,
|
|
CORE_ADDR special_addr)
|
|
{
|
|
struct frame_id id = null_frame_id;
|
|
|
|
id.stack_status = FID_STACK_UNAVAILABLE;
|
|
id.code_addr = code_addr;
|
|
id.code_addr_p = 1;
|
|
id.special_addr = special_addr;
|
|
id.special_addr_p = 1;
|
|
return id;
|
|
}
|
|
|
|
struct frame_id
|
|
frame_id_build (CORE_ADDR stack_addr, CORE_ADDR code_addr)
|
|
{
|
|
struct frame_id id = null_frame_id;
|
|
|
|
id.stack_addr = stack_addr;
|
|
id.stack_status = FID_STACK_VALID;
|
|
id.code_addr = code_addr;
|
|
id.code_addr_p = 1;
|
|
return id;
|
|
}
|
|
|
|
struct frame_id
|
|
frame_id_build_wild (CORE_ADDR stack_addr)
|
|
{
|
|
struct frame_id id = null_frame_id;
|
|
|
|
id.stack_addr = stack_addr;
|
|
id.stack_status = FID_STACK_VALID;
|
|
return id;
|
|
}
|
|
|
|
int
|
|
frame_id_p (struct frame_id l)
|
|
{
|
|
int p;
|
|
|
|
/* The frame is valid iff it has a valid stack address. */
|
|
p = l.stack_status != FID_STACK_INVALID;
|
|
/* outer_frame_id is also valid. */
|
|
if (!p && memcmp (&l, &outer_frame_id, sizeof (l)) == 0)
|
|
p = 1;
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "{ frame_id_p (l=");
|
|
fprint_frame_id (gdb_stdlog, l);
|
|
fprintf_unfiltered (gdb_stdlog, ") -> %d }\n", p);
|
|
}
|
|
return p;
|
|
}
|
|
|
|
int
|
|
frame_id_artificial_p (struct frame_id l)
|
|
{
|
|
if (!frame_id_p (l))
|
|
return 0;
|
|
|
|
return (l.artificial_depth != 0);
|
|
}
|
|
|
|
int
|
|
frame_id_eq (struct frame_id l, struct frame_id r)
|
|
{
|
|
int eq;
|
|
|
|
if (l.stack_status == FID_STACK_INVALID && l.special_addr_p
|
|
&& r.stack_status == FID_STACK_INVALID && r.special_addr_p)
|
|
/* The outermost frame marker is equal to itself. This is the
|
|
dodgy thing about outer_frame_id, since between execution steps
|
|
we might step into another function - from which we can't
|
|
unwind either. More thought required to get rid of
|
|
outer_frame_id. */
|
|
eq = 1;
|
|
else if (l.stack_status == FID_STACK_INVALID
|
|
|| r.stack_status == FID_STACK_INVALID)
|
|
/* Like a NaN, if either ID is invalid, the result is false.
|
|
Note that a frame ID is invalid iff it is the null frame ID. */
|
|
eq = 0;
|
|
else if (l.stack_status != r.stack_status || l.stack_addr != r.stack_addr)
|
|
/* If .stack addresses are different, the frames are different. */
|
|
eq = 0;
|
|
else if (l.code_addr_p && r.code_addr_p && l.code_addr != r.code_addr)
|
|
/* An invalid code addr is a wild card. If .code addresses are
|
|
different, the frames are different. */
|
|
eq = 0;
|
|
else if (l.special_addr_p && r.special_addr_p
|
|
&& l.special_addr != r.special_addr)
|
|
/* An invalid special addr is a wild card (or unused). Otherwise
|
|
if special addresses are different, the frames are different. */
|
|
eq = 0;
|
|
else if (l.artificial_depth != r.artificial_depth)
|
|
/* If artifical depths are different, the frames must be different. */
|
|
eq = 0;
|
|
else
|
|
/* Frames are equal. */
|
|
eq = 1;
|
|
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "{ frame_id_eq (l=");
|
|
fprint_frame_id (gdb_stdlog, l);
|
|
fprintf_unfiltered (gdb_stdlog, ",r=");
|
|
fprint_frame_id (gdb_stdlog, r);
|
|
fprintf_unfiltered (gdb_stdlog, ") -> %d }\n", eq);
|
|
}
|
|
return eq;
|
|
}
|
|
|
|
/* Safety net to check whether frame ID L should be inner to
|
|
frame ID R, according to their stack addresses.
|
|
|
|
This method cannot be used to compare arbitrary frames, as the
|
|
ranges of valid stack addresses may be discontiguous (e.g. due
|
|
to sigaltstack).
|
|
|
|
However, it can be used as safety net to discover invalid frame
|
|
IDs in certain circumstances. Assuming that NEXT is the immediate
|
|
inner frame to THIS and that NEXT and THIS are both NORMAL frames:
|
|
|
|
* The stack address of NEXT must be inner-than-or-equal to the stack
|
|
address of THIS.
|
|
|
|
Therefore, if frame_id_inner (THIS, NEXT) holds, some unwind
|
|
error has occurred.
|
|
|
|
* If NEXT and THIS have different stack addresses, no other frame
|
|
in the frame chain may have a stack address in between.
|
|
|
|
Therefore, if frame_id_inner (TEST, THIS) holds, but
|
|
frame_id_inner (TEST, NEXT) does not hold, TEST cannot refer
|
|
to a valid frame in the frame chain.
|
|
|
|
The sanity checks above cannot be performed when a SIGTRAMP frame
|
|
is involved, because signal handlers might be executed on a different
|
|
stack than the stack used by the routine that caused the signal
|
|
to be raised. This can happen for instance when a thread exceeds
|
|
its maximum stack size. In this case, certain compilers implement
|
|
a stack overflow strategy that cause the handler to be run on a
|
|
different stack. */
|
|
|
|
static int
|
|
frame_id_inner (struct gdbarch *gdbarch, struct frame_id l, struct frame_id r)
|
|
{
|
|
int inner;
|
|
|
|
if (l.stack_status != FID_STACK_VALID || r.stack_status != FID_STACK_VALID)
|
|
/* Like NaN, any operation involving an invalid ID always fails.
|
|
Likewise if either ID has an unavailable stack address. */
|
|
inner = 0;
|
|
else if (l.artificial_depth > r.artificial_depth
|
|
&& l.stack_addr == r.stack_addr
|
|
&& l.code_addr_p == r.code_addr_p
|
|
&& l.special_addr_p == r.special_addr_p
|
|
&& l.special_addr == r.special_addr)
|
|
{
|
|
/* Same function, different inlined functions. */
|
|
const struct block *lb, *rb;
|
|
|
|
gdb_assert (l.code_addr_p && r.code_addr_p);
|
|
|
|
lb = block_for_pc (l.code_addr);
|
|
rb = block_for_pc (r.code_addr);
|
|
|
|
if (lb == NULL || rb == NULL)
|
|
/* Something's gone wrong. */
|
|
inner = 0;
|
|
else
|
|
/* This will return true if LB and RB are the same block, or
|
|
if the block with the smaller depth lexically encloses the
|
|
block with the greater depth. */
|
|
inner = contained_in (lb, rb);
|
|
}
|
|
else
|
|
/* Only return non-zero when strictly inner than. Note that, per
|
|
comment in "frame.h", there is some fuzz here. Frameless
|
|
functions are not strictly inner than (same .stack but
|
|
different .code and/or .special address). */
|
|
inner = gdbarch_inner_than (gdbarch, l.stack_addr, r.stack_addr);
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "{ frame_id_inner (l=");
|
|
fprint_frame_id (gdb_stdlog, l);
|
|
fprintf_unfiltered (gdb_stdlog, ",r=");
|
|
fprint_frame_id (gdb_stdlog, r);
|
|
fprintf_unfiltered (gdb_stdlog, ") -> %d }\n", inner);
|
|
}
|
|
return inner;
|
|
}
|
|
|
|
struct frame_info *
|
|
frame_find_by_id (struct frame_id id)
|
|
{
|
|
struct frame_info *frame, *prev_frame;
|
|
|
|
/* ZERO denotes the null frame, let the caller decide what to do
|
|
about it. Should it instead return get_current_frame()? */
|
|
if (!frame_id_p (id))
|
|
return NULL;
|
|
|
|
/* Check for the sentinel frame. */
|
|
if (frame_id_eq (id, sentinel_frame_id))
|
|
return sentinel_frame;
|
|
|
|
/* Try using the frame stash first. Finding it there removes the need
|
|
to perform the search by looping over all frames, which can be very
|
|
CPU-intensive if the number of frames is very high (the loop is O(n)
|
|
and get_prev_frame performs a series of checks that are relatively
|
|
expensive). This optimization is particularly useful when this function
|
|
is called from another function (such as value_fetch_lazy, case
|
|
VALUE_LVAL (val) == lval_register) which already loops over all frames,
|
|
making the overall behavior O(n^2). */
|
|
frame = frame_stash_find (id);
|
|
if (frame)
|
|
return frame;
|
|
|
|
for (frame = get_current_frame (); ; frame = prev_frame)
|
|
{
|
|
struct frame_id self = get_frame_id (frame);
|
|
|
|
if (frame_id_eq (id, self))
|
|
/* An exact match. */
|
|
return frame;
|
|
|
|
prev_frame = get_prev_frame (frame);
|
|
if (!prev_frame)
|
|
return NULL;
|
|
|
|
/* As a safety net to avoid unnecessary backtracing while trying
|
|
to find an invalid ID, we check for a common situation where
|
|
we can detect from comparing stack addresses that no other
|
|
frame in the current frame chain can have this ID. See the
|
|
comment at frame_id_inner for details. */
|
|
if (get_frame_type (frame) == NORMAL_FRAME
|
|
&& !frame_id_inner (get_frame_arch (frame), id, self)
|
|
&& frame_id_inner (get_frame_arch (prev_frame), id,
|
|
get_frame_id (prev_frame)))
|
|
return NULL;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static CORE_ADDR
|
|
frame_unwind_pc (struct frame_info *this_frame)
|
|
{
|
|
if (this_frame->prev_pc.status == CC_UNKNOWN)
|
|
{
|
|
struct gdbarch *prev_gdbarch;
|
|
CORE_ADDR pc = 0;
|
|
int pc_p = 0;
|
|
|
|
/* The right way. The `pure' way. The one true way. This
|
|
method depends solely on the register-unwind code to
|
|
determine the value of registers in THIS frame, and hence
|
|
the value of this frame's PC (resume address). A typical
|
|
implementation is no more than:
|
|
|
|
frame_unwind_register (this_frame, ISA_PC_REGNUM, buf);
|
|
return extract_unsigned_integer (buf, size of ISA_PC_REGNUM);
|
|
|
|
Note: this method is very heavily dependent on a correct
|
|
register-unwind implementation, it pays to fix that
|
|
method first; this method is frame type agnostic, since
|
|
it only deals with register values, it works with any
|
|
frame. This is all in stark contrast to the old
|
|
FRAME_SAVED_PC which would try to directly handle all the
|
|
different ways that a PC could be unwound. */
|
|
prev_gdbarch = frame_unwind_arch (this_frame);
|
|
|
|
try
|
|
{
|
|
pc = gdbarch_unwind_pc (prev_gdbarch, this_frame);
|
|
pc_p = 1;
|
|
}
|
|
catch (const gdb_exception_error &ex)
|
|
{
|
|
if (ex.error == NOT_AVAILABLE_ERROR)
|
|
{
|
|
this_frame->prev_pc.status = CC_UNAVAILABLE;
|
|
|
|
if (frame_debug)
|
|
fprintf_unfiltered (gdb_stdlog,
|
|
"{ frame_unwind_pc (this_frame=%d)"
|
|
" -> <unavailable> }\n",
|
|
this_frame->level);
|
|
}
|
|
else if (ex.error == OPTIMIZED_OUT_ERROR)
|
|
{
|
|
this_frame->prev_pc.status = CC_NOT_SAVED;
|
|
|
|
if (frame_debug)
|
|
fprintf_unfiltered (gdb_stdlog,
|
|
"{ frame_unwind_pc (this_frame=%d)"
|
|
" -> <not saved> }\n",
|
|
this_frame->level);
|
|
}
|
|
else
|
|
throw;
|
|
}
|
|
|
|
if (pc_p)
|
|
{
|
|
this_frame->prev_pc.value = pc;
|
|
this_frame->prev_pc.status = CC_VALUE;
|
|
if (frame_debug)
|
|
fprintf_unfiltered (gdb_stdlog,
|
|
"{ frame_unwind_pc (this_frame=%d) "
|
|
"-> %s }\n",
|
|
this_frame->level,
|
|
hex_string (this_frame->prev_pc.value));
|
|
}
|
|
}
|
|
|
|
if (this_frame->prev_pc.status == CC_VALUE)
|
|
return this_frame->prev_pc.value;
|
|
else if (this_frame->prev_pc.status == CC_UNAVAILABLE)
|
|
throw_error (NOT_AVAILABLE_ERROR, _("PC not available"));
|
|
else if (this_frame->prev_pc.status == CC_NOT_SAVED)
|
|
throw_error (OPTIMIZED_OUT_ERROR, _("PC not saved"));
|
|
else
|
|
internal_error (__FILE__, __LINE__,
|
|
"unexpected prev_pc status: %d",
|
|
(int) this_frame->prev_pc.status);
|
|
}
|
|
|
|
CORE_ADDR
|
|
frame_unwind_caller_pc (struct frame_info *this_frame)
|
|
{
|
|
this_frame = skip_artificial_frames (this_frame);
|
|
|
|
/* We must have a non-artificial frame. The caller is supposed to check
|
|
the result of frame_unwind_caller_id (), which returns NULL_FRAME_ID
|
|
in this case. */
|
|
gdb_assert (this_frame != NULL);
|
|
|
|
return frame_unwind_pc (this_frame);
|
|
}
|
|
|
|
int
|
|
get_frame_func_if_available (struct frame_info *this_frame, CORE_ADDR *pc)
|
|
{
|
|
struct frame_info *next_frame = this_frame->next;
|
|
|
|
if (!next_frame->prev_func.p)
|
|
{
|
|
CORE_ADDR addr_in_block;
|
|
|
|
/* Make certain that this, and not the adjacent, function is
|
|
found. */
|
|
if (!get_frame_address_in_block_if_available (this_frame, &addr_in_block))
|
|
{
|
|
next_frame->prev_func.p = -1;
|
|
if (frame_debug)
|
|
fprintf_unfiltered (gdb_stdlog,
|
|
"{ get_frame_func (this_frame=%d)"
|
|
" -> unavailable }\n",
|
|
this_frame->level);
|
|
}
|
|
else
|
|
{
|
|
next_frame->prev_func.p = 1;
|
|
next_frame->prev_func.addr = get_pc_function_start (addr_in_block);
|
|
if (frame_debug)
|
|
fprintf_unfiltered (gdb_stdlog,
|
|
"{ get_frame_func (this_frame=%d) -> %s }\n",
|
|
this_frame->level,
|
|
hex_string (next_frame->prev_func.addr));
|
|
}
|
|
}
|
|
|
|
if (next_frame->prev_func.p < 0)
|
|
{
|
|
*pc = -1;
|
|
return 0;
|
|
}
|
|
else
|
|
{
|
|
*pc = next_frame->prev_func.addr;
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
CORE_ADDR
|
|
get_frame_func (struct frame_info *this_frame)
|
|
{
|
|
CORE_ADDR pc;
|
|
|
|
if (!get_frame_func_if_available (this_frame, &pc))
|
|
throw_error (NOT_AVAILABLE_ERROR, _("PC not available"));
|
|
|
|
return pc;
|
|
}
|
|
|
|
std::unique_ptr<readonly_detached_regcache>
|
|
frame_save_as_regcache (struct frame_info *this_frame)
|
|
{
|
|
auto cooked_read = [this_frame] (int regnum, gdb_byte *buf)
|
|
{
|
|
if (!deprecated_frame_register_read (this_frame, regnum, buf))
|
|
return REG_UNAVAILABLE;
|
|
else
|
|
return REG_VALID;
|
|
};
|
|
|
|
std::unique_ptr<readonly_detached_regcache> regcache
|
|
(new readonly_detached_regcache (get_frame_arch (this_frame), cooked_read));
|
|
|
|
return regcache;
|
|
}
|
|
|
|
void
|
|
frame_pop (struct frame_info *this_frame)
|
|
{
|
|
struct frame_info *prev_frame;
|
|
|
|
if (get_frame_type (this_frame) == DUMMY_FRAME)
|
|
{
|
|
/* Popping a dummy frame involves restoring more than just registers.
|
|
dummy_frame_pop does all the work. */
|
|
dummy_frame_pop (get_frame_id (this_frame), inferior_thread ());
|
|
return;
|
|
}
|
|
|
|
/* Ensure that we have a frame to pop to. */
|
|
prev_frame = get_prev_frame_always (this_frame);
|
|
|
|
if (!prev_frame)
|
|
error (_("Cannot pop the initial frame."));
|
|
|
|
/* Ignore TAILCALL_FRAME type frames, they were executed already before
|
|
entering THISFRAME. */
|
|
prev_frame = skip_tailcall_frames (prev_frame);
|
|
|
|
if (prev_frame == NULL)
|
|
error (_("Cannot find the caller frame."));
|
|
|
|
/* Make a copy of all the register values unwound from this frame.
|
|
Save them in a scratch buffer so that there isn't a race between
|
|
trying to extract the old values from the current regcache while
|
|
at the same time writing new values into that same cache. */
|
|
std::unique_ptr<readonly_detached_regcache> scratch
|
|
= frame_save_as_regcache (prev_frame);
|
|
|
|
/* FIXME: cagney/2003-03-16: It should be possible to tell the
|
|
target's register cache that it is about to be hit with a burst
|
|
register transfer and that the sequence of register writes should
|
|
be batched. The pair target_prepare_to_store() and
|
|
target_store_registers() kind of suggest this functionality.
|
|
Unfortunately, they don't implement it. Their lack of a formal
|
|
definition can lead to targets writing back bogus values
|
|
(arguably a bug in the target code mind). */
|
|
/* Now copy those saved registers into the current regcache. */
|
|
get_current_regcache ()->restore (scratch.get ());
|
|
|
|
/* We've made right mess of GDB's local state, just discard
|
|
everything. */
|
|
reinit_frame_cache ();
|
|
}
|
|
|
|
void
|
|
frame_register_unwind (frame_info *next_frame, int regnum,
|
|
int *optimizedp, int *unavailablep,
|
|
enum lval_type *lvalp, CORE_ADDR *addrp,
|
|
int *realnump, gdb_byte *bufferp)
|
|
{
|
|
struct value *value;
|
|
|
|
/* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
|
|
that the value proper does not need to be fetched. */
|
|
gdb_assert (optimizedp != NULL);
|
|
gdb_assert (lvalp != NULL);
|
|
gdb_assert (addrp != NULL);
|
|
gdb_assert (realnump != NULL);
|
|
/* gdb_assert (bufferp != NULL); */
|
|
|
|
value = frame_unwind_register_value (next_frame, regnum);
|
|
|
|
gdb_assert (value != NULL);
|
|
|
|
*optimizedp = value_optimized_out (value);
|
|
*unavailablep = !value_entirely_available (value);
|
|
*lvalp = VALUE_LVAL (value);
|
|
*addrp = value_address (value);
|
|
if (*lvalp == lval_register)
|
|
*realnump = VALUE_REGNUM (value);
|
|
else
|
|
*realnump = -1;
|
|
|
|
if (bufferp)
|
|
{
|
|
if (!*optimizedp && !*unavailablep)
|
|
memcpy (bufferp, value_contents_all (value),
|
|
TYPE_LENGTH (value_type (value)));
|
|
else
|
|
memset (bufferp, 0, TYPE_LENGTH (value_type (value)));
|
|
}
|
|
|
|
/* Dispose of the new value. This prevents watchpoints from
|
|
trying to watch the saved frame pointer. */
|
|
release_value (value);
|
|
}
|
|
|
|
void
|
|
frame_register (struct frame_info *frame, int regnum,
|
|
int *optimizedp, int *unavailablep, enum lval_type *lvalp,
|
|
CORE_ADDR *addrp, int *realnump, gdb_byte *bufferp)
|
|
{
|
|
/* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
|
|
that the value proper does not need to be fetched. */
|
|
gdb_assert (optimizedp != NULL);
|
|
gdb_assert (lvalp != NULL);
|
|
gdb_assert (addrp != NULL);
|
|
gdb_assert (realnump != NULL);
|
|
/* gdb_assert (bufferp != NULL); */
|
|
|
|
/* Obtain the register value by unwinding the register from the next
|
|
(more inner frame). */
|
|
gdb_assert (frame != NULL && frame->next != NULL);
|
|
frame_register_unwind (frame->next, regnum, optimizedp, unavailablep,
|
|
lvalp, addrp, realnump, bufferp);
|
|
}
|
|
|
|
void
|
|
frame_unwind_register (frame_info *next_frame, int regnum, gdb_byte *buf)
|
|
{
|
|
int optimized;
|
|
int unavailable;
|
|
CORE_ADDR addr;
|
|
int realnum;
|
|
enum lval_type lval;
|
|
|
|
frame_register_unwind (next_frame, regnum, &optimized, &unavailable,
|
|
&lval, &addr, &realnum, buf);
|
|
|
|
if (optimized)
|
|
throw_error (OPTIMIZED_OUT_ERROR,
|
|
_("Register %d was not saved"), regnum);
|
|
if (unavailable)
|
|
throw_error (NOT_AVAILABLE_ERROR,
|
|
_("Register %d is not available"), regnum);
|
|
}
|
|
|
|
void
|
|
get_frame_register (struct frame_info *frame,
|
|
int regnum, gdb_byte *buf)
|
|
{
|
|
frame_unwind_register (frame->next, regnum, buf);
|
|
}
|
|
|
|
struct value *
|
|
frame_unwind_register_value (frame_info *next_frame, int regnum)
|
|
{
|
|
struct gdbarch *gdbarch;
|
|
struct value *value;
|
|
|
|
gdb_assert (next_frame != NULL);
|
|
gdbarch = frame_unwind_arch (next_frame);
|
|
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog,
|
|
"{ frame_unwind_register_value "
|
|
"(frame=%d,regnum=%d(%s),...) ",
|
|
next_frame->level, regnum,
|
|
user_reg_map_regnum_to_name (gdbarch, regnum));
|
|
}
|
|
|
|
/* Find the unwinder. */
|
|
if (next_frame->unwind == NULL)
|
|
frame_unwind_find_by_frame (next_frame, &next_frame->prologue_cache);
|
|
|
|
/* Ask this frame to unwind its register. */
|
|
value = next_frame->unwind->prev_register (next_frame,
|
|
&next_frame->prologue_cache,
|
|
regnum);
|
|
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "->");
|
|
if (value_optimized_out (value))
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, " ");
|
|
val_print_optimized_out (value, gdb_stdlog);
|
|
}
|
|
else
|
|
{
|
|
if (VALUE_LVAL (value) == lval_register)
|
|
fprintf_unfiltered (gdb_stdlog, " register=%d",
|
|
VALUE_REGNUM (value));
|
|
else if (VALUE_LVAL (value) == lval_memory)
|
|
fprintf_unfiltered (gdb_stdlog, " address=%s",
|
|
paddress (gdbarch,
|
|
value_address (value)));
|
|
else
|
|
fprintf_unfiltered (gdb_stdlog, " computed");
|
|
|
|
if (value_lazy (value))
|
|
fprintf_unfiltered (gdb_stdlog, " lazy");
|
|
else
|
|
{
|
|
int i;
|
|
const gdb_byte *buf = value_contents (value);
|
|
|
|
fprintf_unfiltered (gdb_stdlog, " bytes=");
|
|
fprintf_unfiltered (gdb_stdlog, "[");
|
|
for (i = 0; i < register_size (gdbarch, regnum); i++)
|
|
fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]);
|
|
fprintf_unfiltered (gdb_stdlog, "]");
|
|
}
|
|
}
|
|
|
|
fprintf_unfiltered (gdb_stdlog, " }\n");
|
|
}
|
|
|
|
return value;
|
|
}
|
|
|
|
struct value *
|
|
get_frame_register_value (struct frame_info *frame, int regnum)
|
|
{
|
|
return frame_unwind_register_value (frame->next, regnum);
|
|
}
|
|
|
|
LONGEST
|
|
frame_unwind_register_signed (frame_info *next_frame, int regnum)
|
|
{
|
|
struct gdbarch *gdbarch = frame_unwind_arch (next_frame);
|
|
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
|
int size = register_size (gdbarch, regnum);
|
|
struct value *value = frame_unwind_register_value (next_frame, regnum);
|
|
|
|
gdb_assert (value != NULL);
|
|
|
|
if (value_optimized_out (value))
|
|
{
|
|
throw_error (OPTIMIZED_OUT_ERROR,
|
|
_("Register %d was not saved"), regnum);
|
|
}
|
|
if (!value_entirely_available (value))
|
|
{
|
|
throw_error (NOT_AVAILABLE_ERROR,
|
|
_("Register %d is not available"), regnum);
|
|
}
|
|
|
|
LONGEST r = extract_signed_integer (value_contents_all (value), size,
|
|
byte_order);
|
|
|
|
release_value (value);
|
|
return r;
|
|
}
|
|
|
|
LONGEST
|
|
get_frame_register_signed (struct frame_info *frame, int regnum)
|
|
{
|
|
return frame_unwind_register_signed (frame->next, regnum);
|
|
}
|
|
|
|
ULONGEST
|
|
frame_unwind_register_unsigned (frame_info *next_frame, int regnum)
|
|
{
|
|
struct gdbarch *gdbarch = frame_unwind_arch (next_frame);
|
|
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
|
int size = register_size (gdbarch, regnum);
|
|
struct value *value = frame_unwind_register_value (next_frame, regnum);
|
|
|
|
gdb_assert (value != NULL);
|
|
|
|
if (value_optimized_out (value))
|
|
{
|
|
throw_error (OPTIMIZED_OUT_ERROR,
|
|
_("Register %d was not saved"), regnum);
|
|
}
|
|
if (!value_entirely_available (value))
|
|
{
|
|
throw_error (NOT_AVAILABLE_ERROR,
|
|
_("Register %d is not available"), regnum);
|
|
}
|
|
|
|
ULONGEST r = extract_unsigned_integer (value_contents_all (value), size,
|
|
byte_order);
|
|
|
|
release_value (value);
|
|
return r;
|
|
}
|
|
|
|
ULONGEST
|
|
get_frame_register_unsigned (struct frame_info *frame, int regnum)
|
|
{
|
|
return frame_unwind_register_unsigned (frame->next, regnum);
|
|
}
|
|
|
|
int
|
|
read_frame_register_unsigned (struct frame_info *frame, int regnum,
|
|
ULONGEST *val)
|
|
{
|
|
struct value *regval = get_frame_register_value (frame, regnum);
|
|
|
|
if (!value_optimized_out (regval)
|
|
&& value_entirely_available (regval))
|
|
{
|
|
struct gdbarch *gdbarch = get_frame_arch (frame);
|
|
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
|
int size = register_size (gdbarch, VALUE_REGNUM (regval));
|
|
|
|
*val = extract_unsigned_integer (value_contents (regval), size, byte_order);
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void
|
|
put_frame_register (struct frame_info *frame, int regnum,
|
|
const gdb_byte *buf)
|
|
{
|
|
struct gdbarch *gdbarch = get_frame_arch (frame);
|
|
int realnum;
|
|
int optim;
|
|
int unavail;
|
|
enum lval_type lval;
|
|
CORE_ADDR addr;
|
|
|
|
frame_register (frame, regnum, &optim, &unavail,
|
|
&lval, &addr, &realnum, NULL);
|
|
if (optim)
|
|
error (_("Attempt to assign to a register that was not saved."));
|
|
switch (lval)
|
|
{
|
|
case lval_memory:
|
|
{
|
|
write_memory (addr, buf, register_size (gdbarch, regnum));
|
|
break;
|
|
}
|
|
case lval_register:
|
|
get_current_regcache ()->cooked_write (realnum, buf);
|
|
break;
|
|
default:
|
|
error (_("Attempt to assign to an unmodifiable value."));
|
|
}
|
|
}
|
|
|
|
/* This function is deprecated. Use get_frame_register_value instead,
|
|
which provides more accurate information.
|
|
|
|
Find and return the value of REGNUM for the specified stack frame.
|
|
The number of bytes copied is REGISTER_SIZE (REGNUM).
|
|
|
|
Returns 0 if the register value could not be found. */
|
|
|
|
int
|
|
deprecated_frame_register_read (struct frame_info *frame, int regnum,
|
|
gdb_byte *myaddr)
|
|
{
|
|
int optimized;
|
|
int unavailable;
|
|
enum lval_type lval;
|
|
CORE_ADDR addr;
|
|
int realnum;
|
|
|
|
frame_register (frame, regnum, &optimized, &unavailable,
|
|
&lval, &addr, &realnum, myaddr);
|
|
|
|
return !optimized && !unavailable;
|
|
}
|
|
|
|
int
|
|
get_frame_register_bytes (struct frame_info *frame, int regnum,
|
|
CORE_ADDR offset, int len, gdb_byte *myaddr,
|
|
int *optimizedp, int *unavailablep)
|
|
{
|
|
struct gdbarch *gdbarch = get_frame_arch (frame);
|
|
int i;
|
|
int maxsize;
|
|
int numregs;
|
|
|
|
/* Skip registers wholly inside of OFFSET. */
|
|
while (offset >= register_size (gdbarch, regnum))
|
|
{
|
|
offset -= register_size (gdbarch, regnum);
|
|
regnum++;
|
|
}
|
|
|
|
/* Ensure that we will not read beyond the end of the register file.
|
|
This can only ever happen if the debug information is bad. */
|
|
maxsize = -offset;
|
|
numregs = gdbarch_num_cooked_regs (gdbarch);
|
|
for (i = regnum; i < numregs; i++)
|
|
{
|
|
int thissize = register_size (gdbarch, i);
|
|
|
|
if (thissize == 0)
|
|
break; /* This register is not available on this architecture. */
|
|
maxsize += thissize;
|
|
}
|
|
if (len > maxsize)
|
|
error (_("Bad debug information detected: "
|
|
"Attempt to read %d bytes from registers."), len);
|
|
|
|
/* Copy the data. */
|
|
while (len > 0)
|
|
{
|
|
int curr_len = register_size (gdbarch, regnum) - offset;
|
|
|
|
if (curr_len > len)
|
|
curr_len = len;
|
|
|
|
if (curr_len == register_size (gdbarch, regnum))
|
|
{
|
|
enum lval_type lval;
|
|
CORE_ADDR addr;
|
|
int realnum;
|
|
|
|
frame_register (frame, regnum, optimizedp, unavailablep,
|
|
&lval, &addr, &realnum, myaddr);
|
|
if (*optimizedp || *unavailablep)
|
|
return 0;
|
|
}
|
|
else
|
|
{
|
|
struct value *value = frame_unwind_register_value (frame->next,
|
|
regnum);
|
|
gdb_assert (value != NULL);
|
|
*optimizedp = value_optimized_out (value);
|
|
*unavailablep = !value_entirely_available (value);
|
|
|
|
if (*optimizedp || *unavailablep)
|
|
{
|
|
release_value (value);
|
|
return 0;
|
|
}
|
|
memcpy (myaddr, value_contents_all (value) + offset, curr_len);
|
|
release_value (value);
|
|
}
|
|
|
|
myaddr += curr_len;
|
|
len -= curr_len;
|
|
offset = 0;
|
|
regnum++;
|
|
}
|
|
|
|
*optimizedp = 0;
|
|
*unavailablep = 0;
|
|
return 1;
|
|
}
|
|
|
|
void
|
|
put_frame_register_bytes (struct frame_info *frame, int regnum,
|
|
CORE_ADDR offset, int len, const gdb_byte *myaddr)
|
|
{
|
|
struct gdbarch *gdbarch = get_frame_arch (frame);
|
|
|
|
/* Skip registers wholly inside of OFFSET. */
|
|
while (offset >= register_size (gdbarch, regnum))
|
|
{
|
|
offset -= register_size (gdbarch, regnum);
|
|
regnum++;
|
|
}
|
|
|
|
/* Copy the data. */
|
|
while (len > 0)
|
|
{
|
|
int curr_len = register_size (gdbarch, regnum) - offset;
|
|
|
|
if (curr_len > len)
|
|
curr_len = len;
|
|
|
|
if (curr_len == register_size (gdbarch, regnum))
|
|
{
|
|
put_frame_register (frame, regnum, myaddr);
|
|
}
|
|
else
|
|
{
|
|
struct value *value = frame_unwind_register_value (frame->next,
|
|
regnum);
|
|
gdb_assert (value != NULL);
|
|
|
|
memcpy ((char *) value_contents_writeable (value) + offset, myaddr,
|
|
curr_len);
|
|
put_frame_register (frame, regnum, value_contents_raw (value));
|
|
release_value (value);
|
|
}
|
|
|
|
myaddr += curr_len;
|
|
len -= curr_len;
|
|
offset = 0;
|
|
regnum++;
|
|
}
|
|
}
|
|
|
|
/* Create a sentinel frame. */
|
|
|
|
static struct frame_info *
|
|
create_sentinel_frame (struct program_space *pspace, struct regcache *regcache)
|
|
{
|
|
struct frame_info *frame = FRAME_OBSTACK_ZALLOC (struct frame_info);
|
|
|
|
frame->level = -1;
|
|
frame->pspace = pspace;
|
|
frame->aspace = regcache->aspace ();
|
|
/* Explicitly initialize the sentinel frame's cache. Provide it
|
|
with the underlying regcache. In the future additional
|
|
information, such as the frame's thread will be added. */
|
|
frame->prologue_cache = sentinel_frame_cache (regcache);
|
|
/* For the moment there is only one sentinel frame implementation. */
|
|
frame->unwind = &sentinel_frame_unwind;
|
|
/* Link this frame back to itself. The frame is self referential
|
|
(the unwound PC is the same as the pc), so make it so. */
|
|
frame->next = frame;
|
|
/* The sentinel frame has a special ID. */
|
|
frame->this_id.p = 1;
|
|
frame->this_id.value = sentinel_frame_id;
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "{ create_sentinel_frame (...) -> ");
|
|
fprint_frame (gdb_stdlog, frame);
|
|
fprintf_unfiltered (gdb_stdlog, " }\n");
|
|
}
|
|
return frame;
|
|
}
|
|
|
|
/* Cache for frame addresses already read by gdb. Valid only while
|
|
inferior is stopped. Control variables for the frame cache should
|
|
be local to this module. */
|
|
|
|
static struct obstack frame_cache_obstack;
|
|
|
|
void *
|
|
frame_obstack_zalloc (unsigned long size)
|
|
{
|
|
void *data = obstack_alloc (&frame_cache_obstack, size);
|
|
|
|
memset (data, 0, size);
|
|
return data;
|
|
}
|
|
|
|
static struct frame_info *get_prev_frame_always_1 (struct frame_info *this_frame);
|
|
|
|
struct frame_info *
|
|
get_current_frame (void)
|
|
{
|
|
struct frame_info *current_frame;
|
|
|
|
/* First check, and report, the lack of registers. Having GDB
|
|
report "No stack!" or "No memory" when the target doesn't even
|
|
have registers is very confusing. Besides, "printcmd.exp"
|
|
explicitly checks that ``print $pc'' with no registers prints "No
|
|
registers". */
|
|
if (!target_has_registers)
|
|
error (_("No registers."));
|
|
if (!target_has_stack)
|
|
error (_("No stack."));
|
|
if (!target_has_memory)
|
|
error (_("No memory."));
|
|
/* Traceframes are effectively a substitute for the live inferior. */
|
|
if (get_traceframe_number () < 0)
|
|
validate_registers_access ();
|
|
|
|
if (sentinel_frame == NULL)
|
|
sentinel_frame =
|
|
create_sentinel_frame (current_program_space, get_current_regcache ());
|
|
|
|
/* Set the current frame before computing the frame id, to avoid
|
|
recursion inside compute_frame_id, in case the frame's
|
|
unwinder decides to do a symbol lookup (which depends on the
|
|
selected frame's block).
|
|
|
|
This call must always succeed. In particular, nothing inside
|
|
get_prev_frame_always_1 should try to unwind from the
|
|
sentinel frame, because that could fail/throw, and we always
|
|
want to leave with the current frame created and linked in --
|
|
we should never end up with the sentinel frame as outermost
|
|
frame. */
|
|
current_frame = get_prev_frame_always_1 (sentinel_frame);
|
|
gdb_assert (current_frame != NULL);
|
|
|
|
return current_frame;
|
|
}
|
|
|
|
/* The "selected" stack frame is used by default for local and arg
|
|
access. May be zero, for no selected frame. */
|
|
|
|
static struct frame_info *selected_frame;
|
|
|
|
int
|
|
has_stack_frames (void)
|
|
{
|
|
if (!target_has_registers || !target_has_stack || !target_has_memory)
|
|
return 0;
|
|
|
|
/* Traceframes are effectively a substitute for the live inferior. */
|
|
if (get_traceframe_number () < 0)
|
|
{
|
|
/* No current inferior, no frame. */
|
|
if (inferior_ptid == null_ptid)
|
|
return 0;
|
|
|
|
thread_info *tp = inferior_thread ();
|
|
/* Don't try to read from a dead thread. */
|
|
if (tp->state == THREAD_EXITED)
|
|
return 0;
|
|
|
|
/* ... or from a spinning thread. */
|
|
if (tp->executing)
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/* Return the selected frame. Always non-NULL (unless there isn't an
|
|
inferior sufficient for creating a frame) in which case an error is
|
|
thrown. */
|
|
|
|
struct frame_info *
|
|
get_selected_frame (const char *message)
|
|
{
|
|
if (selected_frame == NULL)
|
|
{
|
|
if (message != NULL && !has_stack_frames ())
|
|
error (("%s"), message);
|
|
/* Hey! Don't trust this. It should really be re-finding the
|
|
last selected frame of the currently selected thread. This,
|
|
though, is better than nothing. */
|
|
select_frame (get_current_frame ());
|
|
}
|
|
/* There is always a frame. */
|
|
gdb_assert (selected_frame != NULL);
|
|
return selected_frame;
|
|
}
|
|
|
|
/* If there is a selected frame, return it. Otherwise, return NULL. */
|
|
|
|
struct frame_info *
|
|
get_selected_frame_if_set (void)
|
|
{
|
|
return selected_frame;
|
|
}
|
|
|
|
/* This is a variant of get_selected_frame() which can be called when
|
|
the inferior does not have a frame; in that case it will return
|
|
NULL instead of calling error(). */
|
|
|
|
struct frame_info *
|
|
deprecated_safe_get_selected_frame (void)
|
|
{
|
|
if (!has_stack_frames ())
|
|
return NULL;
|
|
return get_selected_frame (NULL);
|
|
}
|
|
|
|
/* Select frame FI (or NULL - to invalidate the current frame). */
|
|
|
|
void
|
|
select_frame (struct frame_info *fi)
|
|
{
|
|
selected_frame = fi;
|
|
/* NOTE: cagney/2002-05-04: FI can be NULL. This occurs when the
|
|
frame is being invalidated. */
|
|
|
|
/* FIXME: kseitz/2002-08-28: It would be nice to call
|
|
selected_frame_level_changed_event() right here, but due to limitations
|
|
in the current interfaces, we would end up flooding UIs with events
|
|
because select_frame() is used extensively internally.
|
|
|
|
Once we have frame-parameterized frame (and frame-related) commands,
|
|
the event notification can be moved here, since this function will only
|
|
be called when the user's selected frame is being changed. */
|
|
|
|
/* Ensure that symbols for this frame are read in. Also, determine the
|
|
source language of this frame, and switch to it if desired. */
|
|
if (fi)
|
|
{
|
|
CORE_ADDR pc;
|
|
|
|
/* We retrieve the frame's symtab by using the frame PC.
|
|
However we cannot use the frame PC as-is, because it usually
|
|
points to the instruction following the "call", which is
|
|
sometimes the first instruction of another function. So we
|
|
rely on get_frame_address_in_block() which provides us with a
|
|
PC which is guaranteed to be inside the frame's code
|
|
block. */
|
|
if (get_frame_address_in_block_if_available (fi, &pc))
|
|
{
|
|
struct compunit_symtab *cust = find_pc_compunit_symtab (pc);
|
|
|
|
if (cust != NULL
|
|
&& compunit_language (cust) != current_language->la_language
|
|
&& compunit_language (cust) != language_unknown
|
|
&& language_mode == language_mode_auto)
|
|
set_language (compunit_language (cust));
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Create an arbitrary (i.e. address specified by user) or innermost frame.
|
|
Always returns a non-NULL value. */
|
|
|
|
struct frame_info *
|
|
create_new_frame (CORE_ADDR addr, CORE_ADDR pc)
|
|
{
|
|
struct frame_info *fi;
|
|
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog,
|
|
"{ create_new_frame (addr=%s, pc=%s) ",
|
|
hex_string (addr), hex_string (pc));
|
|
}
|
|
|
|
fi = FRAME_OBSTACK_ZALLOC (struct frame_info);
|
|
|
|
fi->next = create_sentinel_frame (current_program_space,
|
|
get_current_regcache ());
|
|
|
|
/* Set/update this frame's cached PC value, found in the next frame.
|
|
Do this before looking for this frame's unwinder. A sniffer is
|
|
very likely to read this, and the corresponding unwinder is
|
|
entitled to rely that the PC doesn't magically change. */
|
|
fi->next->prev_pc.value = pc;
|
|
fi->next->prev_pc.status = CC_VALUE;
|
|
|
|
/* We currently assume that frame chain's can't cross spaces. */
|
|
fi->pspace = fi->next->pspace;
|
|
fi->aspace = fi->next->aspace;
|
|
|
|
/* Select/initialize both the unwind function and the frame's type
|
|
based on the PC. */
|
|
frame_unwind_find_by_frame (fi, &fi->prologue_cache);
|
|
|
|
fi->this_id.p = 1;
|
|
fi->this_id.value = frame_id_build (addr, pc);
|
|
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "-> ");
|
|
fprint_frame (gdb_stdlog, fi);
|
|
fprintf_unfiltered (gdb_stdlog, " }\n");
|
|
}
|
|
|
|
return fi;
|
|
}
|
|
|
|
/* Return the frame that THIS_FRAME calls (NULL if THIS_FRAME is the
|
|
innermost frame). Be careful to not fall off the bottom of the
|
|
frame chain and onto the sentinel frame. */
|
|
|
|
struct frame_info *
|
|
get_next_frame (struct frame_info *this_frame)
|
|
{
|
|
if (this_frame->level > 0)
|
|
return this_frame->next;
|
|
else
|
|
return NULL;
|
|
}
|
|
|
|
/* Return the frame that THIS_FRAME calls. If THIS_FRAME is the
|
|
innermost (i.e. current) frame, return the sentinel frame. Thus,
|
|
unlike get_next_frame(), NULL will never be returned. */
|
|
|
|
struct frame_info *
|
|
get_next_frame_sentinel_okay (struct frame_info *this_frame)
|
|
{
|
|
gdb_assert (this_frame != NULL);
|
|
|
|
/* Note that, due to the manner in which the sentinel frame is
|
|
constructed, this_frame->next still works even when this_frame
|
|
is the sentinel frame. But we disallow it here anyway because
|
|
calling get_next_frame_sentinel_okay() on the sentinel frame
|
|
is likely a coding error. */
|
|
gdb_assert (this_frame != sentinel_frame);
|
|
|
|
return this_frame->next;
|
|
}
|
|
|
|
/* Observer for the target_changed event. */
|
|
|
|
static void
|
|
frame_observer_target_changed (struct target_ops *target)
|
|
{
|
|
reinit_frame_cache ();
|
|
}
|
|
|
|
/* Flush the entire frame cache. */
|
|
|
|
void
|
|
reinit_frame_cache (void)
|
|
{
|
|
struct frame_info *fi;
|
|
|
|
/* Tear down all frame caches. */
|
|
for (fi = sentinel_frame; fi != NULL; fi = fi->prev)
|
|
{
|
|
if (fi->prologue_cache && fi->unwind->dealloc_cache)
|
|
fi->unwind->dealloc_cache (fi, fi->prologue_cache);
|
|
if (fi->base_cache && fi->base->unwind->dealloc_cache)
|
|
fi->base->unwind->dealloc_cache (fi, fi->base_cache);
|
|
}
|
|
|
|
/* Since we can't really be sure what the first object allocated was. */
|
|
obstack_free (&frame_cache_obstack, 0);
|
|
obstack_init (&frame_cache_obstack);
|
|
|
|
if (sentinel_frame != NULL)
|
|
annotate_frames_invalid ();
|
|
|
|
sentinel_frame = NULL; /* Invalidate cache */
|
|
select_frame (NULL);
|
|
frame_stash_invalidate ();
|
|
if (frame_debug)
|
|
fprintf_unfiltered (gdb_stdlog, "{ reinit_frame_cache () }\n");
|
|
}
|
|
|
|
/* Find where a register is saved (in memory or another register).
|
|
The result of frame_register_unwind is just where it is saved
|
|
relative to this particular frame. */
|
|
|
|
static void
|
|
frame_register_unwind_location (struct frame_info *this_frame, int regnum,
|
|
int *optimizedp, enum lval_type *lvalp,
|
|
CORE_ADDR *addrp, int *realnump)
|
|
{
|
|
gdb_assert (this_frame == NULL || this_frame->level >= 0);
|
|
|
|
while (this_frame != NULL)
|
|
{
|
|
int unavailable;
|
|
|
|
frame_register_unwind (this_frame, regnum, optimizedp, &unavailable,
|
|
lvalp, addrp, realnump, NULL);
|
|
|
|
if (*optimizedp)
|
|
break;
|
|
|
|
if (*lvalp != lval_register)
|
|
break;
|
|
|
|
regnum = *realnump;
|
|
this_frame = get_next_frame (this_frame);
|
|
}
|
|
}
|
|
|
|
/* Get the previous raw frame, and check that it is not identical to
|
|
same other frame frame already in the chain. If it is, there is
|
|
most likely a stack cycle, so we discard it, and mark THIS_FRAME as
|
|
outermost, with UNWIND_SAME_ID stop reason. Unlike the other
|
|
validity tests, that compare THIS_FRAME and the next frame, we do
|
|
this right after creating the previous frame, to avoid ever ending
|
|
up with two frames with the same id in the frame chain. */
|
|
|
|
static struct frame_info *
|
|
get_prev_frame_if_no_cycle (struct frame_info *this_frame)
|
|
{
|
|
struct frame_info *prev_frame;
|
|
|
|
prev_frame = get_prev_frame_raw (this_frame);
|
|
|
|
/* Don't compute the frame id of the current frame yet. Unwinding
|
|
the sentinel frame can fail (e.g., if the thread is gone and we
|
|
can't thus read its registers). If we let the cycle detection
|
|
code below try to compute a frame ID, then an error thrown from
|
|
within the frame ID computation would result in the sentinel
|
|
frame as outermost frame, which is bogus. Instead, we'll compute
|
|
the current frame's ID lazily in get_frame_id. Note that there's
|
|
no point in doing cycle detection when there's only one frame, so
|
|
nothing is lost here. */
|
|
if (prev_frame->level == 0)
|
|
return prev_frame;
|
|
|
|
try
|
|
{
|
|
compute_frame_id (prev_frame);
|
|
if (!frame_stash_add (prev_frame))
|
|
{
|
|
/* Another frame with the same id was already in the stash. We just
|
|
detected a cycle. */
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "-> ");
|
|
fprint_frame (gdb_stdlog, NULL);
|
|
fprintf_unfiltered (gdb_stdlog, " // this frame has same ID }\n");
|
|
}
|
|
this_frame->stop_reason = UNWIND_SAME_ID;
|
|
/* Unlink. */
|
|
prev_frame->next = NULL;
|
|
this_frame->prev = NULL;
|
|
prev_frame = NULL;
|
|
}
|
|
}
|
|
catch (const gdb_exception &ex)
|
|
{
|
|
prev_frame->next = NULL;
|
|
this_frame->prev = NULL;
|
|
|
|
throw;
|
|
}
|
|
|
|
return prev_frame;
|
|
}
|
|
|
|
/* Helper function for get_prev_frame_always, this is called inside a
|
|
TRY_CATCH block. Return the frame that called THIS_FRAME or NULL if
|
|
there is no such frame. This may throw an exception. */
|
|
|
|
static struct frame_info *
|
|
get_prev_frame_always_1 (struct frame_info *this_frame)
|
|
{
|
|
struct gdbarch *gdbarch;
|
|
|
|
gdb_assert (this_frame != NULL);
|
|
gdbarch = get_frame_arch (this_frame);
|
|
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "{ get_prev_frame_always (this_frame=");
|
|
if (this_frame != NULL)
|
|
fprintf_unfiltered (gdb_stdlog, "%d", this_frame->level);
|
|
else
|
|
fprintf_unfiltered (gdb_stdlog, "<NULL>");
|
|
fprintf_unfiltered (gdb_stdlog, ") ");
|
|
}
|
|
|
|
/* Only try to do the unwind once. */
|
|
if (this_frame->prev_p)
|
|
{
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "-> ");
|
|
fprint_frame (gdb_stdlog, this_frame->prev);
|
|
fprintf_unfiltered (gdb_stdlog, " // cached \n");
|
|
}
|
|
return this_frame->prev;
|
|
}
|
|
|
|
/* If the frame unwinder hasn't been selected yet, we must do so
|
|
before setting prev_p; otherwise the check for misbehaved
|
|
sniffers will think that this frame's sniffer tried to unwind
|
|
further (see frame_cleanup_after_sniffer). */
|
|
if (this_frame->unwind == NULL)
|
|
frame_unwind_find_by_frame (this_frame, &this_frame->prologue_cache);
|
|
|
|
this_frame->prev_p = 1;
|
|
this_frame->stop_reason = UNWIND_NO_REASON;
|
|
|
|
/* If we are unwinding from an inline frame, all of the below tests
|
|
were already performed when we unwound from the next non-inline
|
|
frame. We must skip them, since we can not get THIS_FRAME's ID
|
|
until we have unwound all the way down to the previous non-inline
|
|
frame. */
|
|
if (get_frame_type (this_frame) == INLINE_FRAME)
|
|
return get_prev_frame_if_no_cycle (this_frame);
|
|
|
|
/* Check that this frame is unwindable. If it isn't, don't try to
|
|
unwind to the prev frame. */
|
|
this_frame->stop_reason
|
|
= this_frame->unwind->stop_reason (this_frame,
|
|
&this_frame->prologue_cache);
|
|
|
|
if (this_frame->stop_reason != UNWIND_NO_REASON)
|
|
{
|
|
if (frame_debug)
|
|
{
|
|
enum unwind_stop_reason reason = this_frame->stop_reason;
|
|
|
|
fprintf_unfiltered (gdb_stdlog, "-> ");
|
|
fprint_frame (gdb_stdlog, NULL);
|
|
fprintf_unfiltered (gdb_stdlog, " // %s }\n",
|
|
frame_stop_reason_symbol_string (reason));
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/* Check that this frame's ID isn't inner to (younger, below, next)
|
|
the next frame. This happens when a frame unwind goes backwards.
|
|
This check is valid only if this frame and the next frame are NORMAL.
|
|
See the comment at frame_id_inner for details. */
|
|
if (get_frame_type (this_frame) == NORMAL_FRAME
|
|
&& this_frame->next->unwind->type == NORMAL_FRAME
|
|
&& frame_id_inner (get_frame_arch (this_frame->next),
|
|
get_frame_id (this_frame),
|
|
get_frame_id (this_frame->next)))
|
|
{
|
|
CORE_ADDR this_pc_in_block;
|
|
struct minimal_symbol *morestack_msym;
|
|
const char *morestack_name = NULL;
|
|
|
|
/* gcc -fsplit-stack __morestack can continue the stack anywhere. */
|
|
this_pc_in_block = get_frame_address_in_block (this_frame);
|
|
morestack_msym = lookup_minimal_symbol_by_pc (this_pc_in_block).minsym;
|
|
if (morestack_msym)
|
|
morestack_name = MSYMBOL_LINKAGE_NAME (morestack_msym);
|
|
if (!morestack_name || strcmp (morestack_name, "__morestack") != 0)
|
|
{
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "-> ");
|
|
fprint_frame (gdb_stdlog, NULL);
|
|
fprintf_unfiltered (gdb_stdlog,
|
|
" // this frame ID is inner }\n");
|
|
}
|
|
this_frame->stop_reason = UNWIND_INNER_ID;
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
/* Check that this and the next frame do not unwind the PC register
|
|
to the same memory location. If they do, then even though they
|
|
have different frame IDs, the new frame will be bogus; two
|
|
functions can't share a register save slot for the PC. This can
|
|
happen when the prologue analyzer finds a stack adjustment, but
|
|
no PC save.
|
|
|
|
This check does assume that the "PC register" is roughly a
|
|
traditional PC, even if the gdbarch_unwind_pc method adjusts
|
|
it (we do not rely on the value, only on the unwound PC being
|
|
dependent on this value). A potential improvement would be
|
|
to have the frame prev_pc method and the gdbarch unwind_pc
|
|
method set the same lval and location information as
|
|
frame_register_unwind. */
|
|
if (this_frame->level > 0
|
|
&& gdbarch_pc_regnum (gdbarch) >= 0
|
|
&& get_frame_type (this_frame) == NORMAL_FRAME
|
|
&& (get_frame_type (this_frame->next) == NORMAL_FRAME
|
|
|| get_frame_type (this_frame->next) == INLINE_FRAME))
|
|
{
|
|
int optimized, realnum, nrealnum;
|
|
enum lval_type lval, nlval;
|
|
CORE_ADDR addr, naddr;
|
|
|
|
frame_register_unwind_location (this_frame,
|
|
gdbarch_pc_regnum (gdbarch),
|
|
&optimized, &lval, &addr, &realnum);
|
|
frame_register_unwind_location (get_next_frame (this_frame),
|
|
gdbarch_pc_regnum (gdbarch),
|
|
&optimized, &nlval, &naddr, &nrealnum);
|
|
|
|
if ((lval == lval_memory && lval == nlval && addr == naddr)
|
|
|| (lval == lval_register && lval == nlval && realnum == nrealnum))
|
|
{
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "-> ");
|
|
fprint_frame (gdb_stdlog, NULL);
|
|
fprintf_unfiltered (gdb_stdlog, " // no saved PC }\n");
|
|
}
|
|
|
|
this_frame->stop_reason = UNWIND_NO_SAVED_PC;
|
|
this_frame->prev = NULL;
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
return get_prev_frame_if_no_cycle (this_frame);
|
|
}
|
|
|
|
/* Return a "struct frame_info" corresponding to the frame that called
|
|
THIS_FRAME. Returns NULL if there is no such frame.
|
|
|
|
Unlike get_prev_frame, this function always tries to unwind the
|
|
frame. */
|
|
|
|
struct frame_info *
|
|
get_prev_frame_always (struct frame_info *this_frame)
|
|
{
|
|
struct frame_info *prev_frame = NULL;
|
|
|
|
try
|
|
{
|
|
prev_frame = get_prev_frame_always_1 (this_frame);
|
|
}
|
|
catch (const gdb_exception_error &ex)
|
|
{
|
|
if (ex.error == MEMORY_ERROR)
|
|
{
|
|
this_frame->stop_reason = UNWIND_MEMORY_ERROR;
|
|
if (ex.message != NULL)
|
|
{
|
|
char *stop_string;
|
|
size_t size;
|
|
|
|
/* The error needs to live as long as the frame does.
|
|
Allocate using stack local STOP_STRING then assign the
|
|
pointer to the frame, this allows the STOP_STRING on the
|
|
frame to be of type 'const char *'. */
|
|
size = ex.message->size () + 1;
|
|
stop_string = (char *) frame_obstack_zalloc (size);
|
|
memcpy (stop_string, ex.what (), size);
|
|
this_frame->stop_string = stop_string;
|
|
}
|
|
prev_frame = NULL;
|
|
}
|
|
else
|
|
throw;
|
|
}
|
|
|
|
return prev_frame;
|
|
}
|
|
|
|
/* Construct a new "struct frame_info" and link it previous to
|
|
this_frame. */
|
|
|
|
static struct frame_info *
|
|
get_prev_frame_raw (struct frame_info *this_frame)
|
|
{
|
|
struct frame_info *prev_frame;
|
|
|
|
/* Allocate the new frame but do not wire it in to the frame chain.
|
|
Some (bad) code in INIT_FRAME_EXTRA_INFO tries to look along
|
|
frame->next to pull some fancy tricks (of course such code is, by
|
|
definition, recursive). Try to prevent it.
|
|
|
|
There is no reason to worry about memory leaks, should the
|
|
remainder of the function fail. The allocated memory will be
|
|
quickly reclaimed when the frame cache is flushed, and the `we've
|
|
been here before' check above will stop repeated memory
|
|
allocation calls. */
|
|
prev_frame = FRAME_OBSTACK_ZALLOC (struct frame_info);
|
|
prev_frame->level = this_frame->level + 1;
|
|
|
|
/* For now, assume we don't have frame chains crossing address
|
|
spaces. */
|
|
prev_frame->pspace = this_frame->pspace;
|
|
prev_frame->aspace = this_frame->aspace;
|
|
|
|
/* Don't yet compute ->unwind (and hence ->type). It is computed
|
|
on-demand in get_frame_type, frame_register_unwind, and
|
|
get_frame_id. */
|
|
|
|
/* Don't yet compute the frame's ID. It is computed on-demand by
|
|
get_frame_id(). */
|
|
|
|
/* The unwound frame ID is validate at the start of this function,
|
|
as part of the logic to decide if that frame should be further
|
|
unwound, and not here while the prev frame is being created.
|
|
Doing this makes it possible for the user to examine a frame that
|
|
has an invalid frame ID.
|
|
|
|
Some very old VAX code noted: [...] For the sake of argument,
|
|
suppose that the stack is somewhat trashed (which is one reason
|
|
that "info frame" exists). So, return 0 (indicating we don't
|
|
know the address of the arglist) if we don't know what frame this
|
|
frame calls. */
|
|
|
|
/* Link it in. */
|
|
this_frame->prev = prev_frame;
|
|
prev_frame->next = this_frame;
|
|
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "-> ");
|
|
fprint_frame (gdb_stdlog, prev_frame);
|
|
fprintf_unfiltered (gdb_stdlog, " }\n");
|
|
}
|
|
|
|
return prev_frame;
|
|
}
|
|
|
|
/* Debug routine to print a NULL frame being returned. */
|
|
|
|
static void
|
|
frame_debug_got_null_frame (struct frame_info *this_frame,
|
|
const char *reason)
|
|
{
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "{ get_prev_frame (this_frame=");
|
|
if (this_frame != NULL)
|
|
fprintf_unfiltered (gdb_stdlog, "%d", this_frame->level);
|
|
else
|
|
fprintf_unfiltered (gdb_stdlog, "<NULL>");
|
|
fprintf_unfiltered (gdb_stdlog, ") -> // %s}\n", reason);
|
|
}
|
|
}
|
|
|
|
/* Is this (non-sentinel) frame in the "main"() function? */
|
|
|
|
static int
|
|
inside_main_func (struct frame_info *this_frame)
|
|
{
|
|
struct bound_minimal_symbol msymbol;
|
|
CORE_ADDR maddr;
|
|
|
|
if (symfile_objfile == 0)
|
|
return 0;
|
|
msymbol = lookup_minimal_symbol (main_name (), NULL, symfile_objfile);
|
|
if (msymbol.minsym == NULL)
|
|
return 0;
|
|
/* Make certain that the code, and not descriptor, address is
|
|
returned. */
|
|
maddr = gdbarch_convert_from_func_ptr_addr (get_frame_arch (this_frame),
|
|
BMSYMBOL_VALUE_ADDRESS (msymbol),
|
|
current_top_target ());
|
|
return maddr == get_frame_func (this_frame);
|
|
}
|
|
|
|
/* Test whether THIS_FRAME is inside the process entry point function. */
|
|
|
|
static int
|
|
inside_entry_func (struct frame_info *this_frame)
|
|
{
|
|
CORE_ADDR entry_point;
|
|
|
|
if (!entry_point_address_query (&entry_point))
|
|
return 0;
|
|
|
|
return get_frame_func (this_frame) == entry_point;
|
|
}
|
|
|
|
/* Return a structure containing various interesting information about
|
|
the frame that called THIS_FRAME. Returns NULL if there is entier
|
|
no such frame or the frame fails any of a set of target-independent
|
|
condition that should terminate the frame chain (e.g., as unwinding
|
|
past main()).
|
|
|
|
This function should not contain target-dependent tests, such as
|
|
checking whether the program-counter is zero. */
|
|
|
|
struct frame_info *
|
|
get_prev_frame (struct frame_info *this_frame)
|
|
{
|
|
CORE_ADDR frame_pc;
|
|
int frame_pc_p;
|
|
|
|
/* There is always a frame. If this assertion fails, suspect that
|
|
something should be calling get_selected_frame() or
|
|
get_current_frame(). */
|
|
gdb_assert (this_frame != NULL);
|
|
|
|
/* If this_frame is the current frame, then compute and stash
|
|
its frame id prior to fetching and computing the frame id of the
|
|
previous frame. Otherwise, the cycle detection code in
|
|
get_prev_frame_if_no_cycle() will not work correctly. When
|
|
get_frame_id() is called later on, an assertion error will
|
|
be triggered in the event of a cycle between the current
|
|
frame and its previous frame. */
|
|
if (this_frame->level == 0)
|
|
get_frame_id (this_frame);
|
|
|
|
frame_pc_p = get_frame_pc_if_available (this_frame, &frame_pc);
|
|
|
|
/* tausq/2004-12-07: Dummy frames are skipped because it doesn't make much
|
|
sense to stop unwinding at a dummy frame. One place where a dummy
|
|
frame may have an address "inside_main_func" is on HPUX. On HPUX, the
|
|
pcsqh register (space register for the instruction at the head of the
|
|
instruction queue) cannot be written directly; the only way to set it
|
|
is to branch to code that is in the target space. In order to implement
|
|
frame dummies on HPUX, the called function is made to jump back to where
|
|
the inferior was when the user function was called. If gdb was inside
|
|
the main function when we created the dummy frame, the dummy frame will
|
|
point inside the main function. */
|
|
if (this_frame->level >= 0
|
|
&& get_frame_type (this_frame) == NORMAL_FRAME
|
|
&& !user_set_backtrace_options.backtrace_past_main
|
|
&& frame_pc_p
|
|
&& inside_main_func (this_frame))
|
|
/* Don't unwind past main(). Note, this is done _before_ the
|
|
frame has been marked as previously unwound. That way if the
|
|
user later decides to enable unwinds past main(), that will
|
|
automatically happen. */
|
|
{
|
|
frame_debug_got_null_frame (this_frame, "inside main func");
|
|
return NULL;
|
|
}
|
|
|
|
/* If the user's backtrace limit has been exceeded, stop. We must
|
|
add two to the current level; one of those accounts for backtrace_limit
|
|
being 1-based and the level being 0-based, and the other accounts for
|
|
the level of the new frame instead of the level of the current
|
|
frame. */
|
|
if (this_frame->level + 2 > user_set_backtrace_options.backtrace_limit)
|
|
{
|
|
frame_debug_got_null_frame (this_frame, "backtrace limit exceeded");
|
|
return NULL;
|
|
}
|
|
|
|
/* If we're already inside the entry function for the main objfile,
|
|
then it isn't valid. Don't apply this test to a dummy frame -
|
|
dummy frame PCs typically land in the entry func. Don't apply
|
|
this test to the sentinel frame. Sentinel frames should always
|
|
be allowed to unwind. */
|
|
/* NOTE: cagney/2003-07-07: Fixed a bug in inside_main_func() -
|
|
wasn't checking for "main" in the minimal symbols. With that
|
|
fixed asm-source tests now stop in "main" instead of halting the
|
|
backtrace in weird and wonderful ways somewhere inside the entry
|
|
file. Suspect that tests for inside the entry file/func were
|
|
added to work around that (now fixed) case. */
|
|
/* NOTE: cagney/2003-07-15: danielj (if I'm reading it right)
|
|
suggested having the inside_entry_func test use the
|
|
inside_main_func() msymbol trick (along with entry_point_address()
|
|
I guess) to determine the address range of the start function.
|
|
That should provide a far better stopper than the current
|
|
heuristics. */
|
|
/* NOTE: tausq/2004-10-09: this is needed if, for example, the compiler
|
|
applied tail-call optimizations to main so that a function called
|
|
from main returns directly to the caller of main. Since we don't
|
|
stop at main, we should at least stop at the entry point of the
|
|
application. */
|
|
if (this_frame->level >= 0
|
|
&& get_frame_type (this_frame) == NORMAL_FRAME
|
|
&& !user_set_backtrace_options.backtrace_past_entry
|
|
&& frame_pc_p
|
|
&& inside_entry_func (this_frame))
|
|
{
|
|
frame_debug_got_null_frame (this_frame, "inside entry func");
|
|
return NULL;
|
|
}
|
|
|
|
/* Assume that the only way to get a zero PC is through something
|
|
like a SIGSEGV or a dummy frame, and hence that NORMAL frames
|
|
will never unwind a zero PC. */
|
|
if (this_frame->level > 0
|
|
&& (get_frame_type (this_frame) == NORMAL_FRAME
|
|
|| get_frame_type (this_frame) == INLINE_FRAME)
|
|
&& get_frame_type (get_next_frame (this_frame)) == NORMAL_FRAME
|
|
&& frame_pc_p && frame_pc == 0)
|
|
{
|
|
frame_debug_got_null_frame (this_frame, "zero PC");
|
|
return NULL;
|
|
}
|
|
|
|
return get_prev_frame_always (this_frame);
|
|
}
|
|
|
|
struct frame_id
|
|
get_prev_frame_id_by_id (struct frame_id id)
|
|
{
|
|
struct frame_id prev_id;
|
|
struct frame_info *frame;
|
|
|
|
frame = frame_find_by_id (id);
|
|
|
|
if (frame != NULL)
|
|
prev_id = get_frame_id (get_prev_frame (frame));
|
|
else
|
|
prev_id = null_frame_id;
|
|
|
|
return prev_id;
|
|
}
|
|
|
|
CORE_ADDR
|
|
get_frame_pc (struct frame_info *frame)
|
|
{
|
|
gdb_assert (frame->next != NULL);
|
|
return frame_unwind_pc (frame->next);
|
|
}
|
|
|
|
int
|
|
get_frame_pc_if_available (struct frame_info *frame, CORE_ADDR *pc)
|
|
{
|
|
|
|
gdb_assert (frame->next != NULL);
|
|
|
|
try
|
|
{
|
|
*pc = frame_unwind_pc (frame->next);
|
|
}
|
|
catch (const gdb_exception_error &ex)
|
|
{
|
|
if (ex.error == NOT_AVAILABLE_ERROR)
|
|
return 0;
|
|
else
|
|
throw;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/* Return an address that falls within THIS_FRAME's code block. */
|
|
|
|
CORE_ADDR
|
|
get_frame_address_in_block (struct frame_info *this_frame)
|
|
{
|
|
/* A draft address. */
|
|
CORE_ADDR pc = get_frame_pc (this_frame);
|
|
|
|
struct frame_info *next_frame = this_frame->next;
|
|
|
|
/* Calling get_frame_pc returns the resume address for THIS_FRAME.
|
|
Normally the resume address is inside the body of the function
|
|
associated with THIS_FRAME, but there is a special case: when
|
|
calling a function which the compiler knows will never return
|
|
(for instance abort), the call may be the very last instruction
|
|
in the calling function. The resume address will point after the
|
|
call and may be at the beginning of a different function
|
|
entirely.
|
|
|
|
If THIS_FRAME is a signal frame or dummy frame, then we should
|
|
not adjust the unwound PC. For a dummy frame, GDB pushed the
|
|
resume address manually onto the stack. For a signal frame, the
|
|
OS may have pushed the resume address manually and invoked the
|
|
handler (e.g. GNU/Linux), or invoked the trampoline which called
|
|
the signal handler - but in either case the signal handler is
|
|
expected to return to the trampoline. So in both of these
|
|
cases we know that the resume address is executable and
|
|
related. So we only need to adjust the PC if THIS_FRAME
|
|
is a normal function.
|
|
|
|
If the program has been interrupted while THIS_FRAME is current,
|
|
then clearly the resume address is inside the associated
|
|
function. There are three kinds of interruption: debugger stop
|
|
(next frame will be SENTINEL_FRAME), operating system
|
|
signal or exception (next frame will be SIGTRAMP_FRAME),
|
|
or debugger-induced function call (next frame will be
|
|
DUMMY_FRAME). So we only need to adjust the PC if
|
|
NEXT_FRAME is a normal function.
|
|
|
|
We check the type of NEXT_FRAME first, since it is already
|
|
known; frame type is determined by the unwinder, and since
|
|
we have THIS_FRAME we've already selected an unwinder for
|
|
NEXT_FRAME.
|
|
|
|
If the next frame is inlined, we need to keep going until we find
|
|
the real function - for instance, if a signal handler is invoked
|
|
while in an inlined function, then the code address of the
|
|
"calling" normal function should not be adjusted either. */
|
|
|
|
while (get_frame_type (next_frame) == INLINE_FRAME)
|
|
next_frame = next_frame->next;
|
|
|
|
if ((get_frame_type (next_frame) == NORMAL_FRAME
|
|
|| get_frame_type (next_frame) == TAILCALL_FRAME)
|
|
&& (get_frame_type (this_frame) == NORMAL_FRAME
|
|
|| get_frame_type (this_frame) == TAILCALL_FRAME
|
|
|| get_frame_type (this_frame) == INLINE_FRAME))
|
|
return pc - 1;
|
|
|
|
return pc;
|
|
}
|
|
|
|
int
|
|
get_frame_address_in_block_if_available (struct frame_info *this_frame,
|
|
CORE_ADDR *pc)
|
|
{
|
|
|
|
try
|
|
{
|
|
*pc = get_frame_address_in_block (this_frame);
|
|
}
|
|
catch (const gdb_exception_error &ex)
|
|
{
|
|
if (ex.error == NOT_AVAILABLE_ERROR)
|
|
return 0;
|
|
throw;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
symtab_and_line
|
|
find_frame_sal (frame_info *frame)
|
|
{
|
|
struct frame_info *next_frame;
|
|
int notcurrent;
|
|
CORE_ADDR pc;
|
|
|
|
/* If the next frame represents an inlined function call, this frame's
|
|
sal is the "call site" of that inlined function, which can not
|
|
be inferred from get_frame_pc. */
|
|
next_frame = get_next_frame (frame);
|
|
if (frame_inlined_callees (frame) > 0)
|
|
{
|
|
struct symbol *sym;
|
|
|
|
if (next_frame)
|
|
sym = get_frame_function (next_frame);
|
|
else
|
|
sym = inline_skipped_symbol (inferior_thread ());
|
|
|
|
/* If frame is inline, it certainly has symbols. */
|
|
gdb_assert (sym);
|
|
|
|
symtab_and_line sal;
|
|
if (SYMBOL_LINE (sym) != 0)
|
|
{
|
|
sal.symtab = symbol_symtab (sym);
|
|
sal.line = SYMBOL_LINE (sym);
|
|
}
|
|
else
|
|
/* If the symbol does not have a location, we don't know where
|
|
the call site is. Do not pretend to. This is jarring, but
|
|
we can't do much better. */
|
|
sal.pc = get_frame_pc (frame);
|
|
|
|
sal.pspace = get_frame_program_space (frame);
|
|
return sal;
|
|
}
|
|
|
|
/* If FRAME is not the innermost frame, that normally means that
|
|
FRAME->pc points at the return instruction (which is *after* the
|
|
call instruction), and we want to get the line containing the
|
|
call (because the call is where the user thinks the program is).
|
|
However, if the next frame is either a SIGTRAMP_FRAME or a
|
|
DUMMY_FRAME, then the next frame will contain a saved interrupt
|
|
PC and such a PC indicates the current (rather than next)
|
|
instruction/line, consequently, for such cases, want to get the
|
|
line containing fi->pc. */
|
|
if (!get_frame_pc_if_available (frame, &pc))
|
|
return {};
|
|
|
|
notcurrent = (pc != get_frame_address_in_block (frame));
|
|
return find_pc_line (pc, notcurrent);
|
|
}
|
|
|
|
/* Per "frame.h", return the ``address'' of the frame. Code should
|
|
really be using get_frame_id(). */
|
|
CORE_ADDR
|
|
get_frame_base (struct frame_info *fi)
|
|
{
|
|
return get_frame_id (fi).stack_addr;
|
|
}
|
|
|
|
/* High-level offsets into the frame. Used by the debug info. */
|
|
|
|
CORE_ADDR
|
|
get_frame_base_address (struct frame_info *fi)
|
|
{
|
|
if (get_frame_type (fi) != NORMAL_FRAME)
|
|
return 0;
|
|
if (fi->base == NULL)
|
|
fi->base = frame_base_find_by_frame (fi);
|
|
/* Sneaky: If the low-level unwind and high-level base code share a
|
|
common unwinder, let them share the prologue cache. */
|
|
if (fi->base->unwind == fi->unwind)
|
|
return fi->base->this_base (fi, &fi->prologue_cache);
|
|
return fi->base->this_base (fi, &fi->base_cache);
|
|
}
|
|
|
|
CORE_ADDR
|
|
get_frame_locals_address (struct frame_info *fi)
|
|
{
|
|
if (get_frame_type (fi) != NORMAL_FRAME)
|
|
return 0;
|
|
/* If there isn't a frame address method, find it. */
|
|
if (fi->base == NULL)
|
|
fi->base = frame_base_find_by_frame (fi);
|
|
/* Sneaky: If the low-level unwind and high-level base code share a
|
|
common unwinder, let them share the prologue cache. */
|
|
if (fi->base->unwind == fi->unwind)
|
|
return fi->base->this_locals (fi, &fi->prologue_cache);
|
|
return fi->base->this_locals (fi, &fi->base_cache);
|
|
}
|
|
|
|
CORE_ADDR
|
|
get_frame_args_address (struct frame_info *fi)
|
|
{
|
|
if (get_frame_type (fi) != NORMAL_FRAME)
|
|
return 0;
|
|
/* If there isn't a frame address method, find it. */
|
|
if (fi->base == NULL)
|
|
fi->base = frame_base_find_by_frame (fi);
|
|
/* Sneaky: If the low-level unwind and high-level base code share a
|
|
common unwinder, let them share the prologue cache. */
|
|
if (fi->base->unwind == fi->unwind)
|
|
return fi->base->this_args (fi, &fi->prologue_cache);
|
|
return fi->base->this_args (fi, &fi->base_cache);
|
|
}
|
|
|
|
/* Return true if the frame unwinder for frame FI is UNWINDER; false
|
|
otherwise. */
|
|
|
|
int
|
|
frame_unwinder_is (struct frame_info *fi, const struct frame_unwind *unwinder)
|
|
{
|
|
if (fi->unwind == NULL)
|
|
frame_unwind_find_by_frame (fi, &fi->prologue_cache);
|
|
return fi->unwind == unwinder;
|
|
}
|
|
|
|
/* Level of the selected frame: 0 for innermost, 1 for its caller, ...
|
|
or -1 for a NULL frame. */
|
|
|
|
int
|
|
frame_relative_level (struct frame_info *fi)
|
|
{
|
|
if (fi == NULL)
|
|
return -1;
|
|
else
|
|
return fi->level;
|
|
}
|
|
|
|
enum frame_type
|
|
get_frame_type (struct frame_info *frame)
|
|
{
|
|
if (frame->unwind == NULL)
|
|
/* Initialize the frame's unwinder because that's what
|
|
provides the frame's type. */
|
|
frame_unwind_find_by_frame (frame, &frame->prologue_cache);
|
|
return frame->unwind->type;
|
|
}
|
|
|
|
struct program_space *
|
|
get_frame_program_space (struct frame_info *frame)
|
|
{
|
|
return frame->pspace;
|
|
}
|
|
|
|
struct program_space *
|
|
frame_unwind_program_space (struct frame_info *this_frame)
|
|
{
|
|
gdb_assert (this_frame);
|
|
|
|
/* This is really a placeholder to keep the API consistent --- we
|
|
assume for now that we don't have frame chains crossing
|
|
spaces. */
|
|
return this_frame->pspace;
|
|
}
|
|
|
|
const address_space *
|
|
get_frame_address_space (struct frame_info *frame)
|
|
{
|
|
return frame->aspace;
|
|
}
|
|
|
|
/* Memory access methods. */
|
|
|
|
void
|
|
get_frame_memory (struct frame_info *this_frame, CORE_ADDR addr,
|
|
gdb_byte *buf, int len)
|
|
{
|
|
read_memory (addr, buf, len);
|
|
}
|
|
|
|
LONGEST
|
|
get_frame_memory_signed (struct frame_info *this_frame, CORE_ADDR addr,
|
|
int len)
|
|
{
|
|
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
|
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
|
|
|
return read_memory_integer (addr, len, byte_order);
|
|
}
|
|
|
|
ULONGEST
|
|
get_frame_memory_unsigned (struct frame_info *this_frame, CORE_ADDR addr,
|
|
int len)
|
|
{
|
|
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
|
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
|
|
|
return read_memory_unsigned_integer (addr, len, byte_order);
|
|
}
|
|
|
|
int
|
|
safe_frame_unwind_memory (struct frame_info *this_frame,
|
|
CORE_ADDR addr, gdb_byte *buf, int len)
|
|
{
|
|
/* NOTE: target_read_memory returns zero on success! */
|
|
return !target_read_memory (addr, buf, len);
|
|
}
|
|
|
|
/* Architecture methods. */
|
|
|
|
struct gdbarch *
|
|
get_frame_arch (struct frame_info *this_frame)
|
|
{
|
|
return frame_unwind_arch (this_frame->next);
|
|
}
|
|
|
|
struct gdbarch *
|
|
frame_unwind_arch (struct frame_info *next_frame)
|
|
{
|
|
if (!next_frame->prev_arch.p)
|
|
{
|
|
struct gdbarch *arch;
|
|
|
|
if (next_frame->unwind == NULL)
|
|
frame_unwind_find_by_frame (next_frame, &next_frame->prologue_cache);
|
|
|
|
if (next_frame->unwind->prev_arch != NULL)
|
|
arch = next_frame->unwind->prev_arch (next_frame,
|
|
&next_frame->prologue_cache);
|
|
else
|
|
arch = get_frame_arch (next_frame);
|
|
|
|
next_frame->prev_arch.arch = arch;
|
|
next_frame->prev_arch.p = 1;
|
|
if (frame_debug)
|
|
fprintf_unfiltered (gdb_stdlog,
|
|
"{ frame_unwind_arch (next_frame=%d) -> %s }\n",
|
|
next_frame->level,
|
|
gdbarch_bfd_arch_info (arch)->printable_name);
|
|
}
|
|
|
|
return next_frame->prev_arch.arch;
|
|
}
|
|
|
|
struct gdbarch *
|
|
frame_unwind_caller_arch (struct frame_info *next_frame)
|
|
{
|
|
next_frame = skip_artificial_frames (next_frame);
|
|
|
|
/* We must have a non-artificial frame. The caller is supposed to check
|
|
the result of frame_unwind_caller_id (), which returns NULL_FRAME_ID
|
|
in this case. */
|
|
gdb_assert (next_frame != NULL);
|
|
|
|
return frame_unwind_arch (next_frame);
|
|
}
|
|
|
|
/* Gets the language of FRAME. */
|
|
|
|
enum language
|
|
get_frame_language (struct frame_info *frame)
|
|
{
|
|
CORE_ADDR pc = 0;
|
|
int pc_p = 0;
|
|
|
|
gdb_assert (frame!= NULL);
|
|
|
|
/* We determine the current frame language by looking up its
|
|
associated symtab. To retrieve this symtab, we use the frame
|
|
PC. However we cannot use the frame PC as is, because it
|
|
usually points to the instruction following the "call", which
|
|
is sometimes the first instruction of another function. So
|
|
we rely on get_frame_address_in_block(), it provides us with
|
|
a PC that is guaranteed to be inside the frame's code
|
|
block. */
|
|
|
|
try
|
|
{
|
|
pc = get_frame_address_in_block (frame);
|
|
pc_p = 1;
|
|
}
|
|
catch (const gdb_exception_error &ex)
|
|
{
|
|
if (ex.error != NOT_AVAILABLE_ERROR)
|
|
throw;
|
|
}
|
|
|
|
if (pc_p)
|
|
{
|
|
struct compunit_symtab *cust = find_pc_compunit_symtab (pc);
|
|
|
|
if (cust != NULL)
|
|
return compunit_language (cust);
|
|
}
|
|
|
|
return language_unknown;
|
|
}
|
|
|
|
/* Stack pointer methods. */
|
|
|
|
CORE_ADDR
|
|
get_frame_sp (struct frame_info *this_frame)
|
|
{
|
|
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
|
|
|
/* NOTE drow/2008-06-28: gdbarch_unwind_sp could be converted to
|
|
operate on THIS_FRAME now. */
|
|
return gdbarch_unwind_sp (gdbarch, this_frame->next);
|
|
}
|
|
|
|
/* Return the reason why we can't unwind past FRAME. */
|
|
|
|
enum unwind_stop_reason
|
|
get_frame_unwind_stop_reason (struct frame_info *frame)
|
|
{
|
|
/* Fill-in STOP_REASON. */
|
|
get_prev_frame_always (frame);
|
|
gdb_assert (frame->prev_p);
|
|
|
|
return frame->stop_reason;
|
|
}
|
|
|
|
/* Return a string explaining REASON. */
|
|
|
|
const char *
|
|
unwind_stop_reason_to_string (enum unwind_stop_reason reason)
|
|
{
|
|
switch (reason)
|
|
{
|
|
#define SET(name, description) \
|
|
case name: return _(description);
|
|
#include "unwind_stop_reasons.def"
|
|
#undef SET
|
|
|
|
default:
|
|
internal_error (__FILE__, __LINE__,
|
|
"Invalid frame stop reason");
|
|
}
|
|
}
|
|
|
|
const char *
|
|
frame_stop_reason_string (struct frame_info *fi)
|
|
{
|
|
gdb_assert (fi->prev_p);
|
|
gdb_assert (fi->prev == NULL);
|
|
|
|
/* Return the specific string if we have one. */
|
|
if (fi->stop_string != NULL)
|
|
return fi->stop_string;
|
|
|
|
/* Return the generic string if we have nothing better. */
|
|
return unwind_stop_reason_to_string (fi->stop_reason);
|
|
}
|
|
|
|
/* Return the enum symbol name of REASON as a string, to use in debug
|
|
output. */
|
|
|
|
static const char *
|
|
frame_stop_reason_symbol_string (enum unwind_stop_reason reason)
|
|
{
|
|
switch (reason)
|
|
{
|
|
#define SET(name, description) \
|
|
case name: return #name;
|
|
#include "unwind_stop_reasons.def"
|
|
#undef SET
|
|
|
|
default:
|
|
internal_error (__FILE__, __LINE__,
|
|
"Invalid frame stop reason");
|
|
}
|
|
}
|
|
|
|
/* Clean up after a failed (wrong unwinder) attempt to unwind past
|
|
FRAME. */
|
|
|
|
void
|
|
frame_cleanup_after_sniffer (struct frame_info *frame)
|
|
{
|
|
/* The sniffer should not allocate a prologue cache if it did not
|
|
match this frame. */
|
|
gdb_assert (frame->prologue_cache == NULL);
|
|
|
|
/* No sniffer should extend the frame chain; sniff based on what is
|
|
already certain. */
|
|
gdb_assert (!frame->prev_p);
|
|
|
|
/* The sniffer should not check the frame's ID; that's circular. */
|
|
gdb_assert (!frame->this_id.p);
|
|
|
|
/* Clear cached fields dependent on the unwinder.
|
|
|
|
The previous PC is independent of the unwinder, but the previous
|
|
function is not (see get_frame_address_in_block). */
|
|
frame->prev_func.p = 0;
|
|
frame->prev_func.addr = 0;
|
|
|
|
/* Discard the unwinder last, so that we can easily find it if an assertion
|
|
in this function triggers. */
|
|
frame->unwind = NULL;
|
|
}
|
|
|
|
/* Set FRAME's unwinder temporarily, so that we can call a sniffer.
|
|
If sniffing fails, the caller should be sure to call
|
|
frame_cleanup_after_sniffer. */
|
|
|
|
void
|
|
frame_prepare_for_sniffer (struct frame_info *frame,
|
|
const struct frame_unwind *unwind)
|
|
{
|
|
gdb_assert (frame->unwind == NULL);
|
|
frame->unwind = unwind;
|
|
}
|
|
|
|
static struct cmd_list_element *set_backtrace_cmdlist;
|
|
static struct cmd_list_element *show_backtrace_cmdlist;
|
|
|
|
static void
|
|
set_backtrace_cmd (const char *args, int from_tty)
|
|
{
|
|
help_list (set_backtrace_cmdlist, "set backtrace ", all_commands,
|
|
gdb_stdout);
|
|
}
|
|
|
|
static void
|
|
show_backtrace_cmd (const char *args, int from_tty)
|
|
{
|
|
cmd_show_list (show_backtrace_cmdlist, from_tty, "");
|
|
}
|
|
|
|
/* Definition of the "set backtrace" settings that are exposed as
|
|
"backtrace" command options. */
|
|
|
|
using boolean_option_def
|
|
= gdb::option::boolean_option_def<set_backtrace_options>;
|
|
using uinteger_option_def
|
|
= gdb::option::uinteger_option_def<set_backtrace_options>;
|
|
|
|
const gdb::option::option_def set_backtrace_option_defs[] = {
|
|
|
|
boolean_option_def {
|
|
"past-main",
|
|
[] (set_backtrace_options *opt) { return &opt->backtrace_past_main; },
|
|
show_backtrace_past_main, /* show_cmd_cb */
|
|
N_("Set whether backtraces should continue past \"main\"."),
|
|
N_("Show whether backtraces should continue past \"main\"."),
|
|
N_("Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
|
|
the backtrace at \"main\". Set this if you need to see the rest\n\
|
|
of the stack trace."),
|
|
},
|
|
|
|
boolean_option_def {
|
|
"past-entry",
|
|
[] (set_backtrace_options *opt) { return &opt->backtrace_past_entry; },
|
|
show_backtrace_past_entry, /* show_cmd_cb */
|
|
N_("Set whether backtraces should continue past the entry point of a program."),
|
|
N_("Show whether backtraces should continue past the entry point of a program."),
|
|
N_("Normally there are no callers beyond the entry point of a program, so GDB\n\
|
|
will terminate the backtrace there. Set this if you need to see\n\
|
|
the rest of the stack trace."),
|
|
},
|
|
};
|
|
|
|
void
|
|
_initialize_frame (void)
|
|
{
|
|
obstack_init (&frame_cache_obstack);
|
|
|
|
frame_stash_create ();
|
|
|
|
gdb::observers::target_changed.attach (frame_observer_target_changed);
|
|
|
|
add_prefix_cmd ("backtrace", class_maintenance, set_backtrace_cmd, _("\
|
|
Set backtrace specific variables.\n\
|
|
Configure backtrace variables such as the backtrace limit"),
|
|
&set_backtrace_cmdlist, "set backtrace ",
|
|
0/*allow-unknown*/, &setlist);
|
|
add_prefix_cmd ("backtrace", class_maintenance, show_backtrace_cmd, _("\
|
|
Show backtrace specific variables\n\
|
|
Show backtrace variables such as the backtrace limit"),
|
|
&show_backtrace_cmdlist, "show backtrace ",
|
|
0/*allow-unknown*/, &showlist);
|
|
|
|
add_setshow_uinteger_cmd ("limit", class_obscure,
|
|
&user_set_backtrace_options.backtrace_limit, _("\
|
|
Set an upper bound on the number of backtrace levels."), _("\
|
|
Show the upper bound on the number of backtrace levels."), _("\
|
|
No more than the specified number of frames can be displayed or examined.\n\
|
|
Literal \"unlimited\" or zero means no limit."),
|
|
NULL,
|
|
show_backtrace_limit,
|
|
&set_backtrace_cmdlist,
|
|
&show_backtrace_cmdlist);
|
|
|
|
gdb::option::add_setshow_cmds_for_options
|
|
(class_stack, &user_set_backtrace_options,
|
|
set_backtrace_option_defs, &set_backtrace_cmdlist, &show_backtrace_cmdlist);
|
|
|
|
/* Debug this files internals. */
|
|
add_setshow_zuinteger_cmd ("frame", class_maintenance, &frame_debug, _("\
|
|
Set frame debugging."), _("\
|
|
Show frame debugging."), _("\
|
|
When non-zero, frame specific internal debugging is enabled."),
|
|
NULL,
|
|
show_frame_debug,
|
|
&setdebuglist, &showdebuglist);
|
|
}
|