mirror of
https://sourceware.org/git/binutils-gdb.git
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1be757cfff
* serial.c (serial_for_fd): Delete unused variable. * mdebugread.c (psymtab_to_symtab_1): Delete unused variable. * top.c (execute_command): Delete unused variable. (init_main): Delete unused variable. * utils.c (do_fclose_cleanup): Delete unused variable. (do_all_inferior_continuations): Delete unused variable. (initialize_utils): Delete unused variable. (internal_problem_mode): Delete unused global. * frame.c (get_prev_frame): Delete unused global. (get_frame_locals_address): Delete unused global. (get_frame_args_address): Delete unused global.
2256 lines
70 KiB
C
2256 lines
70 KiB
C
/* Cache and manage frames for GDB, the GNU debugger.
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Copyright (C) 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000, 2001,
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2002, 2003, 2004, 2007, 2008, 2009, 2010 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 "gdb_assert.h"
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#include "gdb_string.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 "observer.h"
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#include "objfiles.h"
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#include "exceptions.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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static struct frame_info *get_prev_frame_1 (struct frame_info *this_frame);
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static struct frame_info *get_prev_frame_raw (struct frame_info *this_frame);
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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; current_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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struct 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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int p;
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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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};
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/* A frame stash used to speed up frame lookups. */
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/* We currently only stash one frame at a time, as this seems to be
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sufficient for now. */
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static struct frame_info *frame_stash = NULL;
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/* Add the following FRAME to the frame stash. */
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static void
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frame_stash_add (struct frame_info *frame)
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{
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frame_stash = frame;
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}
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/* Search the frame stash for an entry with the given frame ID.
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If found, return that frame. Otherwise return 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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if (frame_stash && frame_id_eq (frame_stash->this_id.value, id))
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return frame_stash;
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return NULL;
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}
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/* Invalidate the frame stash by removing all entries in it. */
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static void
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frame_stash_invalidate (void)
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{
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frame_stash = NULL;
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}
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/* Flag to control debugging. */
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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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/* Flag to indicate whether backtraces should stop at main et.al. */
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static int 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 continue past \"main\" is %s.\n"),
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value);
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}
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static int 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, _("\
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Whether backtraces should continue past the entry point of a program is %s.\n"),
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value);
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}
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static int backtrace_limit = INT_MAX;
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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 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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fprint_field (file, "stack", id.stack_addr_p, 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.inline_depth)
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fprintf_unfiltered (file, ",inlined=%d", id.inline_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 SENTINEL_FRAME:
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fprintf_unfiltered (file, "SENTINEL_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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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.p)
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fprintf_unfiltered (file, "%s", hex_string (fi->next->prev_pc.value));
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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, "id=");
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if (fi->this_id.p)
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fprint_frame_id (file, fi->this_id.value);
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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, "func=");
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if (fi->next != NULL && fi->next->prev_func.p)
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fprintf_unfiltered (file, "%s", hex_string (fi->next->prev_func.addr));
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else
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fprintf_unfiltered (file, "<unknown>");
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fprintf_unfiltered (file, "}");
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}
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/* Given FRAME, return the enclosing normal frame for inlined
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function frames. Otherwise return the original frame. */
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static struct frame_info *
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skip_inlined_frames (struct frame_info *frame)
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{
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while (get_frame_type (frame) == INLINE_FRAME)
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frame = get_prev_frame (frame);
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return frame;
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}
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/* Return a frame uniq ID that can be used to, later, re-find the
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frame. */
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struct frame_id
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get_frame_id (struct frame_info *fi)
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{
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if (fi == NULL)
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return null_frame_id;
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if (!fi->this_id.p)
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{
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if (frame_debug)
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fprintf_unfiltered (gdb_stdlog, "{ get_frame_id (fi=%d) ",
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fi->level);
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/* Find the unwinder. */
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if (fi->unwind == NULL)
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fi->unwind = frame_unwind_find_by_frame (fi, &fi->prologue_cache);
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/* Find THIS frame's ID. */
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/* Default to outermost if no ID is found. */
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fi->this_id.value = outer_frame_id;
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fi->unwind->this_id (fi, &fi->prologue_cache, &fi->this_id.value);
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gdb_assert (frame_id_p (fi->this_id.value));
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fi->this_id.p = 1;
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if (frame_debug)
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{
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fprintf_unfiltered (gdb_stdlog, "-> ");
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fprint_frame_id (gdb_stdlog, fi->this_id.value);
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fprintf_unfiltered (gdb_stdlog, " }\n");
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}
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}
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frame_stash_add (fi);
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return fi->this_id.value;
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}
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struct frame_id
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get_stack_frame_id (struct frame_info *next_frame)
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{
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return get_frame_id (skip_inlined_frames (next_frame));
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}
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struct frame_id
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frame_unwind_caller_id (struct frame_info *next_frame)
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{
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struct frame_info *this_frame;
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/* Use get_prev_frame_1, and not get_prev_frame. The latter will truncate
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the frame chain, leading to this function unintentionally
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returning a null_frame_id (e.g., when a caller requests the frame
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ID of "main()"s caller. */
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next_frame = skip_inlined_frames (next_frame);
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this_frame = get_prev_frame_1 (next_frame);
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if (this_frame)
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return get_frame_id (skip_inlined_frames (this_frame));
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else
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return null_frame_id;
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}
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const struct frame_id null_frame_id; /* All zeros. */
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const struct frame_id outer_frame_id = { 0, 0, 0, 0, 0, 1, 0 };
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struct frame_id
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frame_id_build_special (CORE_ADDR stack_addr, CORE_ADDR code_addr,
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CORE_ADDR special_addr)
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{
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struct frame_id id = null_frame_id;
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id.stack_addr = stack_addr;
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id.stack_addr_p = 1;
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id.code_addr = code_addr;
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id.code_addr_p = 1;
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id.special_addr = special_addr;
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id.special_addr_p = 1;
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return id;
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}
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struct frame_id
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frame_id_build (CORE_ADDR stack_addr, CORE_ADDR code_addr)
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{
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struct frame_id id = null_frame_id;
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id.stack_addr = stack_addr;
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id.stack_addr_p = 1;
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id.code_addr = code_addr;
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id.code_addr_p = 1;
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return id;
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}
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struct frame_id
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frame_id_build_wild (CORE_ADDR stack_addr)
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{
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struct frame_id id = null_frame_id;
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id.stack_addr = stack_addr;
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id.stack_addr_p = 1;
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return id;
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}
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int
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frame_id_p (struct frame_id l)
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{
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int p;
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/* The frame is valid iff it has a valid stack address. */
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p = l.stack_addr_p;
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/* outer_frame_id is also valid. */
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if (!p && memcmp (&l, &outer_frame_id, sizeof (l)) == 0)
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p = 1;
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if (frame_debug)
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{
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fprintf_unfiltered (gdb_stdlog, "{ frame_id_p (l=");
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fprint_frame_id (gdb_stdlog, l);
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fprintf_unfiltered (gdb_stdlog, ") -> %d }\n", p);
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}
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return p;
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}
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int
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frame_id_inlined_p (struct frame_id l)
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{
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if (!frame_id_p (l))
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return 0;
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return (l.inline_depth != 0);
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}
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int
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frame_id_eq (struct frame_id l, struct frame_id r)
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{
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int eq;
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if (!l.stack_addr_p && l.special_addr_p && !r.stack_addr_p && r.special_addr_p)
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/* The outermost frame marker is equal to itself. This is the
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dodgy thing about outer_frame_id, since between execution steps
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we might step into another function - from which we can't
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unwind either. More thought required to get rid of
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outer_frame_id. */
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eq = 1;
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else if (!l.stack_addr_p || !r.stack_addr_p)
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/* Like a NaN, if either ID is invalid, the result is false.
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Note that a frame ID is invalid iff it is the null frame ID. */
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eq = 0;
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else if (l.stack_addr != r.stack_addr)
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/* If .stack addresses are different, the frames are different. */
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eq = 0;
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else if (l.code_addr_p && r.code_addr_p && l.code_addr != r.code_addr)
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/* An invalid code addr is a wild card. If .code addresses are
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different, the frames are different. */
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eq = 0;
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else if (l.special_addr_p && r.special_addr_p
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&& l.special_addr != r.special_addr)
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/* An invalid special addr is a wild card (or unused). Otherwise
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if special addresses are different, the frames are different. */
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eq = 0;
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else if (l.inline_depth != r.inline_depth)
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/* If inline depths are different, the frames must be different. */
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eq = 0;
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else
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/* Frames are equal. */
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eq = 1;
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if (frame_debug)
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{
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fprintf_unfiltered (gdb_stdlog, "{ frame_id_eq (l=");
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fprint_frame_id (gdb_stdlog, l);
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fprintf_unfiltered (gdb_stdlog, ",r=");
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fprint_frame_id (gdb_stdlog, r);
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fprintf_unfiltered (gdb_stdlog, ") -> %d }\n", eq);
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}
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return eq;
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}
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/* Safety net to check whether frame ID L should be inner to
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frame ID R, according to their stack addresses.
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This method cannot be used to compare arbitrary frames, as the
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ranges of valid stack addresses may be discontiguous (e.g. due
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to sigaltstack).
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However, it can be used as safety net to discover invalid frame
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IDs in certain circumstances. Assuming that NEXT is the immediate
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inner frame to THIS and that NEXT and THIS are both NORMAL frames:
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|
|
* 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_addr_p || !r.stack_addr_p)
|
|
/* Like NaN, any operation involving an invalid ID always fails. */
|
|
inner = 0;
|
|
else if (l.inline_depth > r.inline_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. */
|
|
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;
|
|
|
|
/* 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 this = get_frame_id (frame);
|
|
if (frame_id_eq (id, this))
|
|
/* 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, this)
|
|
&& 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.p)
|
|
{
|
|
CORE_ADDR pc;
|
|
if (gdbarch_unwind_pc_p (frame_unwind_arch (this_frame)))
|
|
{
|
|
/* 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. */
|
|
pc = gdbarch_unwind_pc (frame_unwind_arch (this_frame), this_frame);
|
|
}
|
|
else
|
|
internal_error (__FILE__, __LINE__, _("No unwind_pc method"));
|
|
this_frame->prev_pc.value = pc;
|
|
this_frame->prev_pc.p = 1;
|
|
if (frame_debug)
|
|
fprintf_unfiltered (gdb_stdlog,
|
|
"{ frame_unwind_caller_pc (this_frame=%d) -> %s }\n",
|
|
this_frame->level,
|
|
hex_string (this_frame->prev_pc.value));
|
|
}
|
|
return this_frame->prev_pc.value;
|
|
}
|
|
|
|
CORE_ADDR
|
|
frame_unwind_caller_pc (struct frame_info *this_frame)
|
|
{
|
|
return frame_unwind_pc (skip_inlined_frames (this_frame));
|
|
}
|
|
|
|
CORE_ADDR
|
|
get_frame_func (struct frame_info *this_frame)
|
|
{
|
|
struct frame_info *next_frame = this_frame->next;
|
|
|
|
if (!next_frame->prev_func.p)
|
|
{
|
|
/* Make certain that this, and not the adjacent, function is
|
|
found. */
|
|
CORE_ADDR addr_in_block = get_frame_address_in_block (this_frame);
|
|
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));
|
|
}
|
|
return next_frame->prev_func.addr;
|
|
}
|
|
|
|
static int
|
|
do_frame_register_read (void *src, int regnum, gdb_byte *buf)
|
|
{
|
|
return frame_register_read (src, regnum, buf);
|
|
}
|
|
|
|
struct regcache *
|
|
frame_save_as_regcache (struct frame_info *this_frame)
|
|
{
|
|
struct address_space *aspace = get_frame_address_space (this_frame);
|
|
struct regcache *regcache = regcache_xmalloc (get_frame_arch (this_frame),
|
|
aspace);
|
|
struct cleanup *cleanups = make_cleanup_regcache_xfree (regcache);
|
|
regcache_save (regcache, do_frame_register_read, this_frame);
|
|
discard_cleanups (cleanups);
|
|
return regcache;
|
|
}
|
|
|
|
void
|
|
frame_pop (struct frame_info *this_frame)
|
|
{
|
|
struct frame_info *prev_frame;
|
|
struct regcache *scratch;
|
|
struct cleanup *cleanups;
|
|
|
|
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));
|
|
return;
|
|
}
|
|
|
|
/* Ensure that we have a frame to pop to. */
|
|
prev_frame = get_prev_frame_1 (this_frame);
|
|
|
|
if (!prev_frame)
|
|
error (_("Cannot pop the initial 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. */
|
|
scratch = frame_save_as_regcache (prev_frame);
|
|
cleanups = make_cleanup_regcache_xfree (scratch);
|
|
|
|
/* 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.
|
|
Here, regcache_cpy() calls regcache_restore(). */
|
|
regcache_cpy (get_current_regcache (), scratch);
|
|
do_cleanups (cleanups);
|
|
|
|
/* We've made right mess of GDB's local state, just discard
|
|
everything. */
|
|
reinit_frame_cache ();
|
|
}
|
|
|
|
void
|
|
frame_register_unwind (struct frame_info *frame, int regnum,
|
|
int *optimizedp, 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 (frame, regnum);
|
|
|
|
gdb_assert (value != NULL);
|
|
|
|
*optimizedp = value_optimized_out (value);
|
|
*lvalp = VALUE_LVAL (value);
|
|
*addrp = value_address (value);
|
|
*realnump = VALUE_REGNUM (value);
|
|
|
|
if (bufferp)
|
|
memcpy (bufferp, value_contents_all (value),
|
|
TYPE_LENGTH (value_type (value)));
|
|
|
|
/* Dispose of the new value. This prevents watchpoints from
|
|
trying to watch the saved frame pointer. */
|
|
release_value (value);
|
|
value_free (value);
|
|
}
|
|
|
|
void
|
|
frame_register (struct frame_info *frame, int regnum,
|
|
int *optimizedp, 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, lvalp, addrp,
|
|
realnump, bufferp);
|
|
}
|
|
|
|
void
|
|
frame_unwind_register (struct frame_info *frame, int regnum, gdb_byte *buf)
|
|
{
|
|
int optimized;
|
|
CORE_ADDR addr;
|
|
int realnum;
|
|
enum lval_type lval;
|
|
frame_register_unwind (frame, regnum, &optimized, &lval, &addr,
|
|
&realnum, buf);
|
|
}
|
|
|
|
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 (struct frame_info *frame, int regnum)
|
|
{
|
|
struct gdbarch *gdbarch;
|
|
struct value *value;
|
|
|
|
gdb_assert (frame != NULL);
|
|
gdbarch = frame_unwind_arch (frame);
|
|
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "\
|
|
{ frame_unwind_register_value (frame=%d,regnum=%d(%s),...) ",
|
|
frame->level, regnum,
|
|
user_reg_map_regnum_to_name (gdbarch, regnum));
|
|
}
|
|
|
|
/* Find the unwinder. */
|
|
if (frame->unwind == NULL)
|
|
frame->unwind = frame_unwind_find_by_frame (frame, &frame->prologue_cache);
|
|
|
|
/* Ask this frame to unwind its register. */
|
|
value = frame->unwind->prev_register (frame, &frame->prologue_cache, regnum);
|
|
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "->");
|
|
if (value_optimized_out (value))
|
|
fprintf_unfiltered (gdb_stdlog, " optimized out");
|
|
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 (struct frame_info *frame, int regnum)
|
|
{
|
|
struct gdbarch *gdbarch = frame_unwind_arch (frame);
|
|
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
|
int size = register_size (gdbarch, regnum);
|
|
gdb_byte buf[MAX_REGISTER_SIZE];
|
|
frame_unwind_register (frame, regnum, buf);
|
|
return extract_signed_integer (buf, size, byte_order);
|
|
}
|
|
|
|
LONGEST
|
|
get_frame_register_signed (struct frame_info *frame, int regnum)
|
|
{
|
|
return frame_unwind_register_signed (frame->next, regnum);
|
|
}
|
|
|
|
ULONGEST
|
|
frame_unwind_register_unsigned (struct frame_info *frame, int regnum)
|
|
{
|
|
struct gdbarch *gdbarch = frame_unwind_arch (frame);
|
|
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
|
int size = register_size (gdbarch, regnum);
|
|
gdb_byte buf[MAX_REGISTER_SIZE];
|
|
frame_unwind_register (frame, regnum, buf);
|
|
return extract_unsigned_integer (buf, size, byte_order);
|
|
}
|
|
|
|
ULONGEST
|
|
get_frame_register_unsigned (struct frame_info *frame, int regnum)
|
|
{
|
|
return frame_unwind_register_unsigned (frame->next, regnum);
|
|
}
|
|
|
|
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;
|
|
enum lval_type lval;
|
|
CORE_ADDR addr;
|
|
frame_register (frame, regnum, &optim, &lval, &addr, &realnum, NULL);
|
|
if (optim)
|
|
error (_("Attempt to assign to a value that was optimized out."));
|
|
switch (lval)
|
|
{
|
|
case lval_memory:
|
|
{
|
|
/* FIXME: write_memory doesn't yet take constant buffers.
|
|
Arrrg! */
|
|
gdb_byte tmp[MAX_REGISTER_SIZE];
|
|
memcpy (tmp, buf, register_size (gdbarch, regnum));
|
|
write_memory (addr, tmp, register_size (gdbarch, regnum));
|
|
break;
|
|
}
|
|
case lval_register:
|
|
regcache_cooked_write (get_current_regcache (), realnum, buf);
|
|
break;
|
|
default:
|
|
error (_("Attempt to assign to an unmodifiable value."));
|
|
}
|
|
}
|
|
|
|
/* frame_register_read ()
|
|
|
|
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
|
|
frame_register_read (struct frame_info *frame, int regnum,
|
|
gdb_byte *myaddr)
|
|
{
|
|
int optimized;
|
|
enum lval_type lval;
|
|
CORE_ADDR addr;
|
|
int realnum;
|
|
frame_register (frame, regnum, &optimized, &lval, &addr, &realnum, myaddr);
|
|
|
|
return !optimized;
|
|
}
|
|
|
|
int
|
|
get_frame_register_bytes (struct frame_info *frame, int regnum,
|
|
CORE_ADDR offset, int len, gdb_byte *myaddr)
|
|
{
|
|
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_regs (gdbarch) + gdbarch_num_pseudo_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)
|
|
{
|
|
warning (_("Bad debug information detected: "
|
|
"Attempt to read %d bytes from registers."), len);
|
|
return 0;
|
|
}
|
|
|
|
/* 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))
|
|
{
|
|
if (!frame_register_read (frame, regnum, myaddr))
|
|
return 0;
|
|
}
|
|
else
|
|
{
|
|
gdb_byte buf[MAX_REGISTER_SIZE];
|
|
if (!frame_register_read (frame, regnum, buf))
|
|
return 0;
|
|
memcpy (myaddr, buf + offset, curr_len);
|
|
}
|
|
|
|
myaddr += curr_len;
|
|
len -= curr_len;
|
|
offset = 0;
|
|
regnum++;
|
|
}
|
|
|
|
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
|
|
{
|
|
gdb_byte buf[MAX_REGISTER_SIZE];
|
|
frame_register_read (frame, regnum, buf);
|
|
memcpy (buf + offset, myaddr, curr_len);
|
|
put_frame_register (frame, regnum, buf);
|
|
}
|
|
|
|
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 = get_regcache_aspace (regcache);
|
|
/* 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;
|
|
/* Make the sentinel frame's ID valid, but invalid. That way all
|
|
comparisons with it should fail. */
|
|
frame->this_id.p = 1;
|
|
frame->this_id.value = null_frame_id;
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "{ create_sentinel_frame (...) -> ");
|
|
fprint_frame (gdb_stdlog, frame);
|
|
fprintf_unfiltered (gdb_stdlog, " }\n");
|
|
}
|
|
return frame;
|
|
}
|
|
|
|
/* Info about the innermost stack frame (contents of FP register) */
|
|
|
|
static struct frame_info *current_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;
|
|
}
|
|
|
|
/* Return the innermost (currently executing) stack frame. This is
|
|
split into two functions. The function unwind_to_current_frame()
|
|
is wrapped in catch exceptions so that, even when the unwind of the
|
|
sentinel frame fails, the function still returns a stack frame. */
|
|
|
|
static int
|
|
unwind_to_current_frame (struct ui_out *ui_out, void *args)
|
|
{
|
|
struct frame_info *frame = get_prev_frame (args);
|
|
/* A sentinel frame can fail to unwind, e.g., because its PC value
|
|
lands in somewhere like start. */
|
|
if (frame == NULL)
|
|
return 1;
|
|
current_frame = frame;
|
|
return 0;
|
|
}
|
|
|
|
struct frame_info *
|
|
get_current_frame (void)
|
|
{
|
|
/* 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)
|
|
{
|
|
if (ptid_equal (inferior_ptid, null_ptid))
|
|
error (_("No selected thread."));
|
|
if (is_exited (inferior_ptid))
|
|
error (_("Invalid selected thread."));
|
|
if (is_executing (inferior_ptid))
|
|
error (_("Target is executing."));
|
|
}
|
|
|
|
if (current_frame == NULL)
|
|
{
|
|
struct frame_info *sentinel_frame =
|
|
create_sentinel_frame (current_program_space, get_current_regcache ());
|
|
if (catch_exceptions (uiout, unwind_to_current_frame, sentinel_frame,
|
|
RETURN_MASK_ERROR) != 0)
|
|
{
|
|
/* Oops! Fake a current frame? Is this useful? It has a PC
|
|
of zero, for instance. */
|
|
current_frame = sentinel_frame;
|
|
}
|
|
}
|
|
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;
|
|
|
|
/* No current inferior, no frame. */
|
|
if (ptid_equal (inferior_ptid, null_ptid))
|
|
return 0;
|
|
|
|
/* Don't try to read from a dead thread. */
|
|
if (is_exited (inferior_ptid))
|
|
return 0;
|
|
|
|
/* ... or from a spinning thread. */
|
|
if (is_executing (inferior_ptid))
|
|
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;
|
|
}
|
|
|
|
/* 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)
|
|
{
|
|
struct symtab *s;
|
|
|
|
selected_frame = fi;
|
|
/* NOTE: cagney/2002-05-04: FI can be NULL. This occurs when the
|
|
frame is being invalidated. */
|
|
if (deprecated_selected_frame_level_changed_hook)
|
|
deprecated_selected_frame_level_changed_hook (frame_relative_level (fi));
|
|
|
|
/* 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)
|
|
{
|
|
/* 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. */
|
|
s = find_pc_symtab (get_frame_address_in_block (fi));
|
|
if (s
|
|
&& s->language != current_language->la_language
|
|
&& s->language != language_unknown
|
|
&& language_mode == language_mode_auto)
|
|
{
|
|
set_language (s->language);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* 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.p = 1;
|
|
|
|
/* 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. */
|
|
fi->unwind = 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;
|
|
}
|
|
|
|
/* 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 = current_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 (current_frame != NULL)
|
|
annotate_frames_invalid ();
|
|
|
|
current_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)
|
|
{
|
|
frame_register_unwind (this_frame, regnum, optimizedp, lvalp,
|
|
addrp, realnump, NULL);
|
|
|
|
if (*optimizedp)
|
|
break;
|
|
|
|
if (*lvalp != lval_register)
|
|
break;
|
|
|
|
regnum = *realnump;
|
|
this_frame = get_next_frame (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. */
|
|
|
|
static struct frame_info *
|
|
get_prev_frame_1 (struct frame_info *this_frame)
|
|
{
|
|
struct frame_id this_id;
|
|
struct gdbarch *gdbarch;
|
|
|
|
gdb_assert (this_frame != NULL);
|
|
gdbarch = get_frame_arch (this_frame);
|
|
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "{ get_prev_frame_1 (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)
|
|
this_frame->unwind
|
|
= 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_raw (this_frame);
|
|
|
|
/* Check that this frame's ID was valid. If it wasn't, don't try to
|
|
unwind to the prev frame. Be careful to not apply this test to
|
|
the sentinel frame. */
|
|
this_id = get_frame_id (this_frame);
|
|
if (this_frame->level >= 0 && frame_id_eq (this_id, outer_frame_id))
|
|
{
|
|
if (frame_debug)
|
|
{
|
|
fprintf_unfiltered (gdb_stdlog, "-> ");
|
|
fprint_frame (gdb_stdlog, NULL);
|
|
fprintf_unfiltered (gdb_stdlog, " // this ID is NULL }\n");
|
|
}
|
|
this_frame->stop_reason = UNWIND_NULL_ID;
|
|
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), this_id,
|
|
get_frame_id (this_frame->next)))
|
|
{
|
|
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 are not identical. If they
|
|
are, there is most likely a stack cycle. As with the inner-than
|
|
test above, avoid comparing the inner-most and sentinel frames. */
|
|
if (this_frame->level > 0
|
|
&& frame_id_eq (this_id, get_frame_id (this_frame->next)))
|
|
{
|
|
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;
|
|
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_raw (this_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 minimal_symbol *msymbol;
|
|
CORE_ADDR maddr;
|
|
|
|
if (symfile_objfile == 0)
|
|
return 0;
|
|
msymbol = lookup_minimal_symbol (main_name (), NULL, symfile_objfile);
|
|
if (msymbol == 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),
|
|
SYMBOL_VALUE_ADDRESS (msymbol),
|
|
¤t_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)
|
|
{
|
|
/* 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);
|
|
|
|
/* 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
|
|
&& !backtrace_past_main
|
|
&& 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 > 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
|
|
&& !backtrace_past_entry
|
|
&& 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
|
|
&& get_frame_pc (this_frame) == 0)
|
|
{
|
|
frame_debug_got_null_frame (this_frame, "zero PC");
|
|
return NULL;
|
|
}
|
|
|
|
return get_prev_frame_1 (this_frame);
|
|
}
|
|
|
|
CORE_ADDR
|
|
get_frame_pc (struct frame_info *frame)
|
|
{
|
|
gdb_assert (frame->next != NULL);
|
|
return frame_unwind_pc (frame->next);
|
|
}
|
|
|
|
/* 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 (this_frame) == NORMAL_FRAME
|
|
|| get_frame_type (this_frame) == INLINE_FRAME))
|
|
return pc - 1;
|
|
|
|
return pc;
|
|
}
|
|
|
|
void
|
|
find_frame_sal (struct frame_info *frame, struct symtab_and_line *sal)
|
|
{
|
|
struct frame_info *next_frame;
|
|
int notcurrent;
|
|
|
|
/* 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_ptid);
|
|
|
|
init_sal (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);
|
|
|
|
return;
|
|
}
|
|
|
|
/* 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. */
|
|
notcurrent = (get_frame_pc (frame) != get_frame_address_in_block (frame));
|
|
(*sal) = find_pc_line (get_frame_pc (frame), 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)
|
|
fi->unwind = 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 = 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;
|
|
}
|
|
|
|
struct 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)
|
|
next_frame->unwind
|
|
= 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)
|
|
{
|
|
return frame_unwind_arch (skip_inlined_frames (next_frame));
|
|
}
|
|
|
|
/* Stack pointer methods. */
|
|
|
|
CORE_ADDR
|
|
get_frame_sp (struct frame_info *this_frame)
|
|
{
|
|
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
|
/* Normality - an architecture that provides a way of obtaining any
|
|
frame inner-most address. */
|
|
if (gdbarch_unwind_sp_p (gdbarch))
|
|
/* 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);
|
|
/* Now things are really are grim. Hope that the value returned by
|
|
the gdbarch_sp_regnum register is meaningful. */
|
|
if (gdbarch_sp_regnum (gdbarch) >= 0)
|
|
return get_frame_register_unsigned (this_frame,
|
|
gdbarch_sp_regnum (gdbarch));
|
|
internal_error (__FILE__, __LINE__, _("Missing unwind SP method"));
|
|
}
|
|
|
|
/* Return the reason why we can't unwind past FRAME. */
|
|
|
|
enum unwind_stop_reason
|
|
get_frame_unwind_stop_reason (struct frame_info *frame)
|
|
{
|
|
/* If we haven't tried to unwind past this point yet, then assume
|
|
that unwinding would succeed. */
|
|
if (frame->prev_p == 0)
|
|
return UNWIND_NO_REASON;
|
|
|
|
/* Otherwise, we set a reason when we succeeded (or failed) to
|
|
unwind. */
|
|
return frame->stop_reason;
|
|
}
|
|
|
|
/* Return a string explaining REASON. */
|
|
|
|
const char *
|
|
frame_stop_reason_string (enum unwind_stop_reason reason)
|
|
{
|
|
switch (reason)
|
|
{
|
|
case UNWIND_NULL_ID:
|
|
return _("unwinder did not report frame ID");
|
|
|
|
case UNWIND_INNER_ID:
|
|
return _("previous frame inner to this frame (corrupt stack?)");
|
|
|
|
case UNWIND_SAME_ID:
|
|
return _("previous frame identical to this frame (corrupt stack?)");
|
|
|
|
case UNWIND_NO_SAVED_PC:
|
|
return _("frame did not save the PC");
|
|
|
|
case UNWIND_NO_REASON:
|
|
case UNWIND_FIRST_ERROR:
|
|
default:
|
|
internal_error (__FILE__, __LINE__,
|
|
"Invalid frame stop reason");
|
|
}
|
|
}
|
|
|
|
/* Clean up after a failed (wrong unwinder) attempt to unwind past
|
|
FRAME. */
|
|
|
|
static void
|
|
frame_cleanup_after_sniffer (void *arg)
|
|
{
|
|
struct frame_info *frame = arg;
|
|
|
|
/* 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.
|
|
Return a cleanup which should be called if unwinding fails, and
|
|
discarded if it succeeds. */
|
|
|
|
struct cleanup *
|
|
frame_prepare_for_sniffer (struct frame_info *frame,
|
|
const struct frame_unwind *unwind)
|
|
{
|
|
gdb_assert (frame->unwind == NULL);
|
|
frame->unwind = unwind;
|
|
return make_cleanup (frame_cleanup_after_sniffer, frame);
|
|
}
|
|
|
|
extern initialize_file_ftype _initialize_frame; /* -Wmissing-prototypes */
|
|
|
|
static struct cmd_list_element *set_backtrace_cmdlist;
|
|
static struct cmd_list_element *show_backtrace_cmdlist;
|
|
|
|
static void
|
|
set_backtrace_cmd (char *args, int from_tty)
|
|
{
|
|
help_list (set_backtrace_cmdlist, "set backtrace ", -1, gdb_stdout);
|
|
}
|
|
|
|
static void
|
|
show_backtrace_cmd (char *args, int from_tty)
|
|
{
|
|
cmd_show_list (show_backtrace_cmdlist, from_tty, "");
|
|
}
|
|
|
|
void
|
|
_initialize_frame (void)
|
|
{
|
|
obstack_init (&frame_cache_obstack);
|
|
|
|
observer_attach_target_changed (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_boolean_cmd ("past-main", class_obscure,
|
|
&backtrace_past_main, _("\
|
|
Set whether backtraces should continue past \"main\"."), _("\
|
|
Show whether backtraces should continue past \"main\"."), _("\
|
|
Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
|
|
the backtrace at \"main\". Set this variable if you need to see the rest\n\
|
|
of the stack trace."),
|
|
NULL,
|
|
show_backtrace_past_main,
|
|
&set_backtrace_cmdlist,
|
|
&show_backtrace_cmdlist);
|
|
|
|
add_setshow_boolean_cmd ("past-entry", class_obscure,
|
|
&backtrace_past_entry, _("\
|
|
Set whether backtraces should continue past the entry point of a program."),
|
|
_("\
|
|
Show 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\n\
|
|
will terminate the backtrace there. Set this variable if you need to see \n\
|
|
the rest of the stack trace."),
|
|
NULL,
|
|
show_backtrace_past_entry,
|
|
&set_backtrace_cmdlist,
|
|
&show_backtrace_cmdlist);
|
|
|
|
add_setshow_integer_cmd ("limit", class_obscure,
|
|
&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\
|
|
Zero is unlimited."),
|
|
NULL,
|
|
show_backtrace_limit,
|
|
&set_backtrace_cmdlist,
|
|
&show_backtrace_cmdlist);
|
|
|
|
/* Debug this files internals. */
|
|
add_setshow_zinteger_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);
|
|
}
|