d62d1979c4
* frame.c (frame_saved_regs_id_unwind): Assert FRAME_CHAIN_P. (legacy_get_prev_frame): Assert FRAME_CHAIN_P. (get_prev_frame): When FRAME_CHAIN_P, call legacy_get_prev_frame. (frame_saved_regs_pc_unwind): Assert FRAME_SAVED_PC_P. * gdbarch.sh (FRAME_CHAIN): Change to a function with predicate. (FRAME_SAVED_PC): Change to a function with predicate. * gdbarch.h, gdbarch.c: Re-generate.
1529 lines
49 KiB
C
1529 lines
49 KiB
C
/* Cache and manage frames for GDB, the GNU debugger.
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Copyright 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000,
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2001, 2002, 2003 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 2 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, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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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 "builtin-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 "command.h"
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#include "gdbcmd.h"
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/* Flag to indicate whether backtraces should stop at main. */
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static int backtrace_below_main;
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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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{
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return null_frame_id;
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}
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else
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{
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struct frame_id id;
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id.base = fi->frame;
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id.pc = fi->pc;
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return id;
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}
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}
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const struct frame_id null_frame_id; /* All zeros. */
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struct frame_id
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frame_id_build (CORE_ADDR base, CORE_ADDR func_or_pc)
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{
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struct frame_id id;
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id.base = base;
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id.pc = func_or_pc;
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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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/* The .func can be NULL but the .base cannot. */
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return (l.base != 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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/* If .base is different, the frames are different. */
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if (l.base != r.base)
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return 0;
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/* Add a test to check that the frame ID's are for the same function
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here. */
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return 1;
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}
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int
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frame_id_inner (struct frame_id l, struct frame_id r)
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{
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/* Only return non-zero when strictly inner than. Note that, per
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comment in "frame.h", there is some fuzz here. Frameless
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functions are not strictly inner than (same .base but different
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.func). */
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return INNER_THAN (l.base, r.base);
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}
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struct frame_info *
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frame_find_by_id (struct frame_id id)
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{
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struct frame_info *frame;
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/* ZERO denotes the null frame, let the caller decide what to do
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about it. Should it instead return get_current_frame()? */
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if (!frame_id_p (id))
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return NULL;
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for (frame = get_current_frame ();
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frame != NULL;
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frame = get_prev_frame (frame))
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{
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struct frame_id this = get_frame_id (frame);
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if (frame_id_eq (id, this))
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/* An exact match. */
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return frame;
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if (frame_id_inner (id, this))
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/* Gone to far. */
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return NULL;
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/* Either, we're not yet gone far enough out along the frame
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chain (inner(this,id), or we're comparing frameless functions
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(same .base, different .func, no test available). Struggle
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on until we've definitly gone to far. */
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}
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return NULL;
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}
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CORE_ADDR
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frame_pc_unwind (struct frame_info *frame)
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{
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if (!frame->pc_unwind_cache_p)
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{
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frame->pc_unwind_cache = frame->unwind->pc (frame, &frame->unwind_cache);
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frame->pc_unwind_cache_p = 1;
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}
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return frame->pc_unwind_cache;
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}
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struct frame_id
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frame_id_unwind (struct frame_info *frame)
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{
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if (!frame->id_unwind_cache_p)
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{
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frame->unwind->id (frame, &frame->unwind_cache, &frame->id_unwind_cache);
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frame->id_unwind_cache_p = 1;
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}
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return frame->id_unwind_cache;
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}
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void
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frame_pop (struct frame_info *frame)
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{
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/* FIXME: cagney/2003-01-18: There is probably a chicken-egg problem
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with passing in current_regcache. The pop function needs to be
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written carefully so as to not overwrite registers whose [old]
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values are needed to restore other registers. Instead, this code
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should pass in a scratch cache and, as a second step, restore the
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registers using that. */
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frame->unwind->pop (frame, &frame->unwind_cache, current_regcache);
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flush_cached_frames ();
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}
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void
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frame_register_unwind (struct frame_info *frame, int regnum,
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int *optimizedp, enum lval_type *lvalp,
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CORE_ADDR *addrp, int *realnump, void *bufferp)
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{
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struct frame_unwind_cache *cache;
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/* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
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that the value proper does not need to be fetched. */
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gdb_assert (optimizedp != NULL);
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gdb_assert (lvalp != NULL);
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gdb_assert (addrp != NULL);
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gdb_assert (realnump != NULL);
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/* gdb_assert (bufferp != NULL); */
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/* NOTE: cagney/2002-11-27: A program trying to unwind a NULL frame
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is broken. There is always a frame. If there, for some reason,
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isn't, there is some pretty busted code as it should have
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detected the problem before calling here. */
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gdb_assert (frame != NULL);
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/* Ask this frame to unwind its register. */
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frame->unwind->reg (frame, &frame->unwind_cache, regnum,
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optimizedp, lvalp, addrp, realnump, bufferp);
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}
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void
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frame_register (struct frame_info *frame, int regnum,
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int *optimizedp, enum lval_type *lvalp,
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CORE_ADDR *addrp, int *realnump, void *bufferp)
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{
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/* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
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that the value proper does not need to be fetched. */
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gdb_assert (optimizedp != NULL);
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gdb_assert (lvalp != NULL);
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gdb_assert (addrp != NULL);
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gdb_assert (realnump != NULL);
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/* gdb_assert (bufferp != NULL); */
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/* Ulgh! Old code that, for lval_register, sets ADDRP to the offset
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of the register in the register cache. It should instead return
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the REGNUM corresponding to that register. Translate the . */
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if (GET_SAVED_REGISTER_P ())
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{
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GET_SAVED_REGISTER (bufferp, optimizedp, addrp, frame, regnum, lvalp);
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/* Compute the REALNUM if the caller wants it. */
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if (*lvalp == lval_register)
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{
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int regnum;
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for (regnum = 0; regnum < NUM_REGS + NUM_PSEUDO_REGS; regnum++)
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{
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if (*addrp == register_offset_hack (current_gdbarch, regnum))
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{
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*realnump = regnum;
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return;
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}
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}
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internal_error (__FILE__, __LINE__,
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"Failed to compute the register number corresponding"
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" to 0x%s", paddr_d (*addrp));
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}
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*realnump = -1;
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return;
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}
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/* Obtain the register value by unwinding the register from the next
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(more inner frame). */
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gdb_assert (frame != NULL && frame->next != NULL);
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frame_register_unwind (frame->next, regnum, optimizedp, lvalp, addrp,
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realnump, bufferp);
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}
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void
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frame_unwind_signed_register (struct frame_info *frame, int regnum,
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LONGEST *val)
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{
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int optimized;
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CORE_ADDR addr;
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int realnum;
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enum lval_type lval;
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void *buf = alloca (MAX_REGISTER_RAW_SIZE);
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frame_register_unwind (frame, regnum, &optimized, &lval, &addr,
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&realnum, buf);
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(*val) = extract_signed_integer (buf, REGISTER_VIRTUAL_SIZE (regnum));
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}
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void
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frame_unwind_unsigned_register (struct frame_info *frame, int regnum,
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ULONGEST *val)
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{
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int optimized;
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CORE_ADDR addr;
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int realnum;
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enum lval_type lval;
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void *buf = alloca (MAX_REGISTER_RAW_SIZE);
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frame_register_unwind (frame, regnum, &optimized, &lval, &addr,
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&realnum, buf);
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(*val) = extract_unsigned_integer (buf, REGISTER_VIRTUAL_SIZE (regnum));
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}
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void
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frame_read_unsigned_register (struct frame_info *frame, int regnum,
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ULONGEST *val)
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{
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/* NOTE: cagney/2002-10-31: There is a bit of dogma here - there is
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always a frame. Both this, and the equivalent
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frame_read_signed_register() function, can only be called with a
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valid frame. If, for some reason, this function is called
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without a frame then the problem isn't here, but rather in the
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caller. It should of first created a frame and then passed that
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in. */
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/* NOTE: cagney/2002-10-31: As a side bar, keep in mind that the
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``current_frame'' should not be treated as a special case. While
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``get_next_frame (current_frame) == NULL'' currently holds, it
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should, as far as possible, not be relied upon. In the future,
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``get_next_frame (current_frame)'' may instead simply return a
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normal frame object that simply always gets register values from
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the register cache. Consequently, frame code should try to avoid
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tests like ``if get_next_frame() == NULL'' and instead just rely
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on recursive frame calls (like the below code) when manipulating
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a frame chain. */
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gdb_assert (frame != NULL && frame->next != NULL);
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frame_unwind_unsigned_register (frame->next, regnum, val);
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}
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void
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frame_read_signed_register (struct frame_info *frame, int regnum,
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LONGEST *val)
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{
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/* See note above in frame_read_unsigned_register(). */
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gdb_assert (frame != NULL && frame->next != NULL);
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frame_unwind_signed_register (frame->next, regnum, val);
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}
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static void
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generic_unwind_get_saved_register (char *raw_buffer,
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int *optimizedp,
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CORE_ADDR *addrp,
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struct frame_info *frame,
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int regnum,
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enum lval_type *lvalp)
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{
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int optimizedx;
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CORE_ADDR addrx;
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int realnumx;
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enum lval_type lvalx;
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if (!target_has_registers)
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error ("No registers.");
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/* Keep things simple, ensure that all the pointers (except valuep)
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are non NULL. */
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if (optimizedp == NULL)
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optimizedp = &optimizedx;
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if (lvalp == NULL)
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lvalp = &lvalx;
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if (addrp == NULL)
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addrp = &addrx;
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gdb_assert (frame != NULL && frame->next != NULL);
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frame_register_unwind (frame->next, regnum, optimizedp, lvalp, addrp,
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&realnumx, raw_buffer);
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}
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void
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get_saved_register (char *raw_buffer,
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int *optimized,
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CORE_ADDR *addrp,
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struct frame_info *frame,
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int regnum,
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enum lval_type *lval)
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{
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if (GET_SAVED_REGISTER_P ())
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{
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GET_SAVED_REGISTER (raw_buffer, optimized, addrp, frame, regnum, lval);
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return;
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}
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generic_unwind_get_saved_register (raw_buffer, optimized, addrp, frame,
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regnum, lval);
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}
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/* frame_register_read ()
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Find and return the value of REGNUM for the specified stack frame.
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The number of bytes copied is REGISTER_RAW_SIZE (REGNUM).
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Returns 0 if the register value could not be found. */
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int
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frame_register_read (struct frame_info *frame, int regnum, void *myaddr)
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{
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int optimized;
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enum lval_type lval;
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CORE_ADDR addr;
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int realnum;
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frame_register (frame, regnum, &optimized, &lval, &addr, &realnum, myaddr);
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/* FIXME: cagney/2002-05-15: This test, is just bogus.
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It indicates that the target failed to supply a value for a
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register because it was "not available" at this time. Problem
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is, the target still has the register and so get saved_register()
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may be returning a value saved on the stack. */
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if (register_cached (regnum) < 0)
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return 0; /* register value not available */
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return !optimized;
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}
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/* Map between a frame register number and its name. A frame register
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space is a superset of the cooked register space --- it also
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includes builtin registers. */
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int
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frame_map_name_to_regnum (const char *name, int len)
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{
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int i;
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/* Search register name space. */
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for (i = 0; i < NUM_REGS + NUM_PSEUDO_REGS; i++)
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if (REGISTER_NAME (i) && len == strlen (REGISTER_NAME (i))
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&& strncmp (name, REGISTER_NAME (i), len) == 0)
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{
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return i;
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}
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|
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/* Try builtin registers. */
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i = builtin_reg_map_name_to_regnum (name, len);
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if (i >= 0)
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{
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/* A builtin register doesn't fall into the architecture's
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register range. */
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gdb_assert (i >= NUM_REGS + NUM_PSEUDO_REGS);
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return i;
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}
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return -1;
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}
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const char *
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frame_map_regnum_to_name (int regnum)
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{
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if (regnum < 0)
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return NULL;
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if (regnum < NUM_REGS + NUM_PSEUDO_REGS)
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return REGISTER_NAME (regnum);
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return builtin_reg_map_regnum_to_name (regnum);
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}
|
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|
|
/* Create a sentinel frame. */
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struct frame_info *
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create_sentinel_frame (struct regcache *regcache)
|
|
{
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|
struct frame_info *frame = FRAME_OBSTACK_ZALLOC (struct frame_info);
|
|
frame->type = NORMAL_FRAME;
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|
frame->level = -1;
|
|
/* Explicitly initialize the sentinel frame's cache. Provide it
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|
with the underlying regcache. In the future additional
|
|
information, such as the frame's thread will be added. */
|
|
frame->unwind_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. */
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|
frame->next = frame;
|
|
/* Always unwind the PC as part of creating this frame. This
|
|
ensures that the frame's PC points at something valid. */
|
|
/* FIXME: cagney/2003-01-10: Problem here. Unwinding a sentinel
|
|
frame's PC may require information such as the frame's thread's
|
|
stop reason. Is it possible to get to that? */
|
|
frame->pc = frame_pc_unwind (frame);
|
|
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;
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|
}
|
|
|
|
CORE_ADDR *
|
|
frame_saved_regs_zalloc (struct frame_info *fi)
|
|
{
|
|
fi->saved_regs = (CORE_ADDR *)
|
|
frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS);
|
|
return fi->saved_regs;
|
|
}
|
|
|
|
CORE_ADDR *
|
|
get_frame_saved_regs (struct frame_info *fi)
|
|
{
|
|
return fi->saved_regs;
|
|
}
|
|
|
|
/* 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. */
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|
|
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, eg, because it's PC value
|
|
lands in somewhere like start. */
|
|
if (frame == NULL)
|
|
return 1;
|
|
current_frame = frame;
|
|
return 0;
|
|
}
|
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|
|
struct frame_info *
|
|
get_current_frame (void)
|
|
{
|
|
if (!target_has_stack)
|
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error ("No stack.");
|
|
if (!target_has_registers)
|
|
error ("No registers.");
|
|
if (!target_has_memory)
|
|
error ("No memory.");
|
|
if (current_frame == NULL)
|
|
{
|
|
struct frame_info *sentinel_frame =
|
|
create_sentinel_frame (current_regcache);
|
|
if (catch_exceptions (uiout, unwind_to_current_frame, sentinel_frame,
|
|
NULL, 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. */
|
|
|
|
struct frame_info *deprecated_selected_frame;
|
|
|
|
/* 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 (void)
|
|
{
|
|
if (deprecated_selected_frame == NULL)
|
|
/* 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 (deprecated_selected_frame != NULL);
|
|
return deprecated_selected_frame;
|
|
}
|
|
|
|
/* Select frame FI (or NULL - to invalidate the current frame). */
|
|
|
|
void
|
|
select_frame (struct frame_info *fi)
|
|
{
|
|
register struct symtab *s;
|
|
|
|
deprecated_selected_frame = fi;
|
|
/* NOTE: cagney/2002-05-04: FI can be NULL. This occures when the
|
|
frame is being invalidated. */
|
|
if (selected_frame_level_changed_hook)
|
|
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 users 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)
|
|
{
|
|
s = find_pc_symtab (fi->pc);
|
|
if (s
|
|
&& s->language != current_language->la_language
|
|
&& s->language != language_unknown
|
|
&& language_mode == language_mode_auto)
|
|
{
|
|
set_language (s->language);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Return the register saved in the simplistic ``saved_regs'' cache.
|
|
If the value isn't here AND a value is needed, try the next inner
|
|
most frame. */
|
|
|
|
static void
|
|
frame_saved_regs_register_unwind (struct frame_info *frame, void **cache,
|
|
int regnum, int *optimizedp,
|
|
enum lval_type *lvalp, CORE_ADDR *addrp,
|
|
int *realnump, void *bufferp)
|
|
{
|
|
/* There is always a frame at this point. And THIS is the frame
|
|
we're interested in. */
|
|
gdb_assert (frame != NULL);
|
|
/* If we're using generic dummy frames, we'd better not be in a call
|
|
dummy. (generic_call_dummy_register_unwind ought to have been called
|
|
instead.) */
|
|
gdb_assert (!(DEPRECATED_USE_GENERIC_DUMMY_FRAMES
|
|
&& (get_frame_type (frame) == DUMMY_FRAME)));
|
|
|
|
/* Only (older) architectures that implement the
|
|
FRAME_INIT_SAVED_REGS method should be using this function. */
|
|
gdb_assert (FRAME_INIT_SAVED_REGS_P ());
|
|
|
|
/* Load the saved_regs register cache. */
|
|
if (get_frame_saved_regs (frame) == NULL)
|
|
FRAME_INIT_SAVED_REGS (frame);
|
|
|
|
if (get_frame_saved_regs (frame) != NULL
|
|
&& get_frame_saved_regs (frame)[regnum] != 0)
|
|
{
|
|
if (regnum == SP_REGNUM)
|
|
{
|
|
/* SP register treated specially. */
|
|
*optimizedp = 0;
|
|
*lvalp = not_lval;
|
|
*addrp = 0;
|
|
*realnump = -1;
|
|
if (bufferp != NULL)
|
|
store_address (bufferp, REGISTER_RAW_SIZE (regnum),
|
|
get_frame_saved_regs (frame)[regnum]);
|
|
}
|
|
else
|
|
{
|
|
/* Any other register is saved in memory, fetch it but cache
|
|
a local copy of its value. */
|
|
*optimizedp = 0;
|
|
*lvalp = lval_memory;
|
|
*addrp = get_frame_saved_regs (frame)[regnum];
|
|
*realnump = -1;
|
|
if (bufferp != NULL)
|
|
{
|
|
#if 1
|
|
/* Save each register value, as it is read in, in a
|
|
frame based cache. */
|
|
void **regs = (*cache);
|
|
if (regs == NULL)
|
|
{
|
|
int sizeof_cache = ((NUM_REGS + NUM_PSEUDO_REGS)
|
|
* sizeof (void *));
|
|
regs = frame_obstack_zalloc (sizeof_cache);
|
|
(*cache) = regs;
|
|
}
|
|
if (regs[regnum] == NULL)
|
|
{
|
|
regs[regnum]
|
|
= frame_obstack_zalloc (REGISTER_RAW_SIZE (regnum));
|
|
read_memory (get_frame_saved_regs (frame)[regnum], regs[regnum],
|
|
REGISTER_RAW_SIZE (regnum));
|
|
}
|
|
memcpy (bufferp, regs[regnum], REGISTER_RAW_SIZE (regnum));
|
|
#else
|
|
/* Read the value in from memory. */
|
|
read_memory (get_frame_saved_regs (frame)[regnum], bufferp,
|
|
REGISTER_RAW_SIZE (regnum));
|
|
#endif
|
|
}
|
|
}
|
|
return;
|
|
}
|
|
|
|
/* No luck, assume this and the next frame have the same register
|
|
value. Pass the request down the frame chain to the next frame.
|
|
Hopefully that will find the register's location, either in a
|
|
register or in memory. */
|
|
frame_register (frame, regnum, optimizedp, lvalp, addrp, realnump,
|
|
bufferp);
|
|
}
|
|
|
|
static CORE_ADDR
|
|
frame_saved_regs_pc_unwind (struct frame_info *frame, void **cache)
|
|
{
|
|
gdb_assert (FRAME_SAVED_PC_P ());
|
|
return FRAME_SAVED_PC (frame);
|
|
}
|
|
|
|
static void
|
|
frame_saved_regs_id_unwind (struct frame_info *next_frame, void **cache,
|
|
struct frame_id *id)
|
|
{
|
|
int fromleaf;
|
|
CORE_ADDR base;
|
|
CORE_ADDR pc;
|
|
|
|
/* Start out by assuming it's NULL. */
|
|
(*id) = null_frame_id;
|
|
|
|
if (frame_relative_level (next_frame) <= 0)
|
|
/* FIXME: 2002-11-09: Frameless functions can occure anywhere in
|
|
the frame chain, not just the inner most frame! The generic,
|
|
per-architecture, frame code should handle this and the below
|
|
should simply be removed. */
|
|
fromleaf = FRAMELESS_FUNCTION_INVOCATION (next_frame);
|
|
else
|
|
fromleaf = 0;
|
|
|
|
if (fromleaf)
|
|
/* A frameless inner-most frame. The `FP' (which isn't an
|
|
architecture frame-pointer register!) of the caller is the same
|
|
as the callee. */
|
|
/* FIXME: 2002-11-09: There isn't any reason to special case this
|
|
edge condition. Instead the per-architecture code should hande
|
|
it locally. */
|
|
base = get_frame_base (next_frame);
|
|
else
|
|
{
|
|
/* Two macros defined in tm.h specify the machine-dependent
|
|
actions to be performed here.
|
|
|
|
First, get the frame's chain-pointer.
|
|
|
|
If that is zero, the frame is the outermost frame or a leaf
|
|
called by the outermost frame. This means that if start
|
|
calls main without a frame, we'll return 0 (which is fine
|
|
anyway).
|
|
|
|
Nope; there's a problem. This also returns when the current
|
|
routine is a leaf of main. This is unacceptable. We move
|
|
this to after the ffi test; I'd rather have backtraces from
|
|
start go curfluy than have an abort called from main not show
|
|
main. */
|
|
gdb_assert (FRAME_CHAIN_P ());
|
|
base = FRAME_CHAIN (next_frame);
|
|
|
|
if (!frame_chain_valid (base, next_frame))
|
|
return;
|
|
}
|
|
if (base == 0)
|
|
return;
|
|
|
|
/* FIXME: cagney/2002-06-08: This should probably return the frame's
|
|
function and not the PC (a.k.a. resume address). */
|
|
pc = frame_pc_unwind (next_frame);
|
|
id->pc = pc;
|
|
id->base = base;
|
|
}
|
|
|
|
static void
|
|
frame_saved_regs_pop (struct frame_info *fi, void **cache,
|
|
struct regcache *regcache)
|
|
{
|
|
gdb_assert (POP_FRAME_P ());
|
|
POP_FRAME;
|
|
}
|
|
|
|
const struct frame_unwind trad_frame_unwinder = {
|
|
frame_saved_regs_pop,
|
|
frame_saved_regs_pc_unwind,
|
|
frame_saved_regs_id_unwind,
|
|
frame_saved_regs_register_unwind
|
|
};
|
|
const struct frame_unwind *trad_frame_unwind = &trad_frame_unwinder;
|
|
|
|
|
|
/* Function: get_saved_register
|
|
Find register number REGNUM relative to FRAME and put its (raw,
|
|
target format) contents in *RAW_BUFFER.
|
|
|
|
Set *OPTIMIZED if the variable was optimized out (and thus can't be
|
|
fetched). Note that this is never set to anything other than zero
|
|
in this implementation.
|
|
|
|
Set *LVAL to lval_memory, lval_register, or not_lval, depending on
|
|
whether the value was fetched from memory, from a register, or in a
|
|
strange and non-modifiable way (e.g. a frame pointer which was
|
|
calculated rather than fetched). We will use not_lval for values
|
|
fetched from generic dummy frames.
|
|
|
|
Set *ADDRP to the address, either in memory or as a REGISTER_BYTE
|
|
offset into the registers array. If the value is stored in a dummy
|
|
frame, set *ADDRP to zero.
|
|
|
|
To use this implementation, define a function called
|
|
"get_saved_register" in your target code, which simply passes all
|
|
of its arguments to this function.
|
|
|
|
The argument RAW_BUFFER must point to aligned memory. */
|
|
|
|
void
|
|
deprecated_generic_get_saved_register (char *raw_buffer, int *optimized,
|
|
CORE_ADDR *addrp,
|
|
struct frame_info *frame, int regnum,
|
|
enum lval_type *lval)
|
|
{
|
|
if (!target_has_registers)
|
|
error ("No registers.");
|
|
|
|
gdb_assert (FRAME_INIT_SAVED_REGS_P ());
|
|
|
|
/* Normal systems don't optimize out things with register numbers. */
|
|
if (optimized != NULL)
|
|
*optimized = 0;
|
|
|
|
if (addrp) /* default assumption: not found in memory */
|
|
*addrp = 0;
|
|
|
|
/* Note: since the current frame's registers could only have been
|
|
saved by frames INTERIOR TO the current frame, we skip examining
|
|
the current frame itself: otherwise, we would be getting the
|
|
previous frame's registers which were saved by the current frame. */
|
|
|
|
if (frame != NULL)
|
|
{
|
|
for (frame = get_next_frame (frame);
|
|
frame_relative_level (frame) >= 0;
|
|
frame = get_next_frame (frame))
|
|
{
|
|
if (get_frame_type (frame) == DUMMY_FRAME)
|
|
{
|
|
if (lval) /* found it in a CALL_DUMMY frame */
|
|
*lval = not_lval;
|
|
if (raw_buffer)
|
|
/* FIXME: cagney/2002-06-26: This should be via the
|
|
gdbarch_register_read() method so that it, on the
|
|
fly, constructs either a raw or pseudo register
|
|
from the raw register cache. */
|
|
regcache_raw_read
|
|
(generic_find_dummy_frame (get_frame_pc (frame),
|
|
get_frame_base (frame)),
|
|
regnum, raw_buffer);
|
|
return;
|
|
}
|
|
|
|
FRAME_INIT_SAVED_REGS (frame);
|
|
if (get_frame_saved_regs (frame) != NULL
|
|
&& get_frame_saved_regs (frame)[regnum] != 0)
|
|
{
|
|
if (lval) /* found it saved on the stack */
|
|
*lval = lval_memory;
|
|
if (regnum == SP_REGNUM)
|
|
{
|
|
if (raw_buffer) /* SP register treated specially */
|
|
store_address (raw_buffer, REGISTER_RAW_SIZE (regnum),
|
|
get_frame_saved_regs (frame)[regnum]);
|
|
}
|
|
else
|
|
{
|
|
if (addrp) /* any other register */
|
|
*addrp = get_frame_saved_regs (frame)[regnum];
|
|
if (raw_buffer)
|
|
read_memory (get_frame_saved_regs (frame)[regnum], raw_buffer,
|
|
REGISTER_RAW_SIZE (regnum));
|
|
}
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* If we get thru the loop to this point, it means the register was
|
|
not saved in any frame. Return the actual live-register value. */
|
|
|
|
if (lval) /* found it in a live register */
|
|
*lval = lval_register;
|
|
if (addrp)
|
|
*addrp = REGISTER_BYTE (regnum);
|
|
if (raw_buffer)
|
|
deprecated_read_register_gen (regnum, raw_buffer);
|
|
}
|
|
|
|
/* Determine the frame's type based on its PC. */
|
|
|
|
static enum frame_type
|
|
frame_type_from_pc (CORE_ADDR pc)
|
|
{
|
|
/* FIXME: cagney/2002-11-24: Can't yet directly call
|
|
pc_in_dummy_frame() as some architectures don't set
|
|
PC_IN_CALL_DUMMY() to generic_pc_in_call_dummy() (remember the
|
|
latter is implemented by simply calling pc_in_dummy_frame). */
|
|
if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
|
|
&& DEPRECATED_PC_IN_CALL_DUMMY (pc, 0, 0))
|
|
return DUMMY_FRAME;
|
|
else
|
|
{
|
|
char *name;
|
|
find_pc_partial_function (pc, &name, NULL, NULL);
|
|
if (PC_IN_SIGTRAMP (pc, name))
|
|
return SIGTRAMP_FRAME;
|
|
else
|
|
return NORMAL_FRAME;
|
|
}
|
|
}
|
|
|
|
/* 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;
|
|
|
|
fi = frame_obstack_zalloc (sizeof (struct frame_info));
|
|
|
|
fi->frame = addr;
|
|
fi->pc = pc;
|
|
fi->next = create_sentinel_frame (current_regcache);
|
|
fi->type = frame_type_from_pc (pc);
|
|
|
|
if (INIT_EXTRA_FRAME_INFO_P ())
|
|
INIT_EXTRA_FRAME_INFO (0, fi);
|
|
|
|
/* Select/initialize an unwind function. */
|
|
fi->unwind = frame_unwind_find_by_pc (current_gdbarch, fi->pc);
|
|
|
|
return fi;
|
|
}
|
|
|
|
/* Return the frame that FRAME calls (NULL if 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 *frame)
|
|
{
|
|
if (frame->level > 0)
|
|
return frame->next;
|
|
else
|
|
return NULL;
|
|
}
|
|
|
|
/* Flush the entire frame cache. */
|
|
|
|
void
|
|
flush_cached_frames (void)
|
|
{
|
|
/* Since we can't really be sure what the first object allocated was */
|
|
obstack_free (&frame_cache_obstack, 0);
|
|
obstack_init (&frame_cache_obstack);
|
|
|
|
current_frame = NULL; /* Invalidate cache */
|
|
select_frame (NULL);
|
|
annotate_frames_invalid ();
|
|
}
|
|
|
|
/* Flush the frame cache, and start a new one if necessary. */
|
|
|
|
void
|
|
reinit_frame_cache (void)
|
|
{
|
|
flush_cached_frames ();
|
|
|
|
/* FIXME: The inferior_ptid test is wrong if there is a corefile. */
|
|
if (PIDGET (inferior_ptid) != 0)
|
|
{
|
|
select_frame (get_current_frame ());
|
|
}
|
|
}
|
|
|
|
/* Create the previous frame using the deprecated methods
|
|
INIT_EXTRA_INFO, INIT_FRAME_PC and INIT_FRAME_PC_FIRST. */
|
|
|
|
static struct frame_info *
|
|
legacy_get_prev_frame (struct frame_info *next_frame)
|
|
{
|
|
CORE_ADDR address = 0;
|
|
struct frame_info *prev;
|
|
int fromleaf;
|
|
|
|
/* This code only works on normal frames. A sentinel frame, where
|
|
the level is -1, should never reach this code. */
|
|
gdb_assert (next_frame->level >= 0);
|
|
|
|
/* On some machines it is possible to call a function without
|
|
setting up a stack frame for it. On these machines, we
|
|
define this macro to take two args; a frameinfo pointer
|
|
identifying a frame and a variable to set or clear if it is
|
|
or isn't leafless. */
|
|
|
|
/* Still don't want to worry about this except on the innermost
|
|
frame. This macro will set FROMLEAF if NEXT_FRAME is a frameless
|
|
function invocation. */
|
|
if (next_frame->level == 0)
|
|
/* FIXME: 2002-11-09: Frameless functions can occure anywhere in
|
|
the frame chain, not just the inner most frame! The generic,
|
|
per-architecture, frame code should handle this and the below
|
|
should simply be removed. */
|
|
fromleaf = FRAMELESS_FUNCTION_INVOCATION (next_frame);
|
|
else
|
|
fromleaf = 0;
|
|
|
|
if (fromleaf)
|
|
/* A frameless inner-most frame. The `FP' (which isn't an
|
|
architecture frame-pointer register!) of the caller is the same
|
|
as the callee. */
|
|
/* FIXME: 2002-11-09: There isn't any reason to special case this
|
|
edge condition. Instead the per-architecture code should hande
|
|
it locally. */
|
|
address = get_frame_base (next_frame);
|
|
else
|
|
{
|
|
/* Two macros defined in tm.h specify the machine-dependent
|
|
actions to be performed here.
|
|
|
|
First, get the frame's chain-pointer.
|
|
|
|
If that is zero, the frame is the outermost frame or a leaf
|
|
called by the outermost frame. This means that if start
|
|
calls main without a frame, we'll return 0 (which is fine
|
|
anyway).
|
|
|
|
Nope; there's a problem. This also returns when the current
|
|
routine is a leaf of main. This is unacceptable. We move
|
|
this to after the ffi test; I'd rather have backtraces from
|
|
start go curfluy than have an abort called from main not show
|
|
main. */
|
|
gdb_assert (FRAME_CHAIN_P ());
|
|
address = FRAME_CHAIN (next_frame);
|
|
|
|
if (!frame_chain_valid (address, next_frame))
|
|
return 0;
|
|
}
|
|
if (address == 0)
|
|
return 0;
|
|
|
|
/* Create an initially zero previous frame. */
|
|
prev = frame_obstack_zalloc (sizeof (struct frame_info));
|
|
|
|
/* Link it in. */
|
|
next_frame->prev = prev;
|
|
prev->next = next_frame;
|
|
prev->frame = address;
|
|
prev->level = next_frame->level + 1;
|
|
/* FIXME: cagney/2002-11-18: Should be setting the frame's type
|
|
here, before anything else, and not last. Various INIT functions
|
|
are full of work-arounds for the frames type not being set
|
|
correctly from the word go. Ulgh! */
|
|
prev->type = NORMAL_FRAME;
|
|
|
|
/* This change should not be needed, FIXME! We should determine
|
|
whether any targets *need* DEPRECATED_INIT_FRAME_PC to happen
|
|
after INIT_EXTRA_FRAME_INFO and come up with a simple way to
|
|
express what goes on here.
|
|
|
|
INIT_EXTRA_FRAME_INFO is called from two places: create_new_frame
|
|
(where the PC is already set up) and here (where it isn't).
|
|
DEPRECATED_INIT_FRAME_PC is only called from here, always after
|
|
INIT_EXTRA_FRAME_INFO.
|
|
|
|
The catch is the MIPS, where INIT_EXTRA_FRAME_INFO requires the
|
|
PC value (which hasn't been set yet). Some other machines appear
|
|
to require INIT_EXTRA_FRAME_INFO before they can do
|
|
DEPRECATED_INIT_FRAME_PC. Phoo.
|
|
|
|
We shouldn't need DEPRECATED_INIT_FRAME_PC_FIRST to add more
|
|
complication to an already overcomplicated part of GDB.
|
|
gnu@cygnus.com, 15Sep92.
|
|
|
|
Assuming that some machines need DEPRECATED_INIT_FRAME_PC after
|
|
INIT_EXTRA_FRAME_INFO, one possible scheme:
|
|
|
|
SETUP_INNERMOST_FRAME(): Default version is just create_new_frame
|
|
(read_fp ()), read_pc ()). Machines with extra frame info would
|
|
do that (or the local equivalent) and then set the extra fields.
|
|
|
|
SETUP_ARBITRARY_FRAME(argc, argv): Only change here is that
|
|
create_new_frame would no longer init extra frame info;
|
|
SETUP_ARBITRARY_FRAME would have to do that.
|
|
|
|
INIT_PREV_FRAME(fromleaf, prev) Replace INIT_EXTRA_FRAME_INFO and
|
|
DEPRECATED_INIT_FRAME_PC. This should also return a flag saying
|
|
whether to keep the new frame, or whether to discard it, because
|
|
on some machines (e.g. mips) it is really awkward to have
|
|
FRAME_CHAIN_VALID called *before* INIT_EXTRA_FRAME_INFO (there is
|
|
no good way to get information deduced in FRAME_CHAIN_VALID into
|
|
the extra fields of the new frame). std_frame_pc(fromleaf, prev)
|
|
|
|
This is the default setting for INIT_PREV_FRAME. It just does
|
|
what the default DEPRECATED_INIT_FRAME_PC does. Some machines
|
|
will call it from INIT_PREV_FRAME (either at the beginning, the
|
|
end, or in the middle). Some machines won't use it.
|
|
|
|
kingdon@cygnus.com, 13Apr93, 31Jan94, 14Dec94. */
|
|
|
|
/* NOTE: cagney/2002-11-09: Just ignore the above! There is no
|
|
reason for things to be this complicated.
|
|
|
|
The trick is to assume that there is always a frame. Instead of
|
|
special casing the inner-most frame, create fake frame
|
|
(containing the hardware registers) that is inner to the
|
|
user-visible inner-most frame (...) and then unwind from that.
|
|
That way architecture code can use use the standard
|
|
frame_XX_unwind() functions and not differentiate between the
|
|
inner most and any other case.
|
|
|
|
Since there is always a frame to unwind from, there is always
|
|
somewhere (NEXT_FRAME) to store all the info needed to construct
|
|
a new (previous) frame without having to first create it. This
|
|
means that the convolution below - needing to carefully order a
|
|
frame's initialization - isn't needed.
|
|
|
|
The irony here though, is that FRAME_CHAIN(), at least for a more
|
|
up-to-date architecture, always calls FRAME_SAVED_PC(), and
|
|
FRAME_SAVED_PC() computes the PC but without first needing the
|
|
frame! Instead of the convolution below, we could have simply
|
|
called FRAME_SAVED_PC() and been done with it! Note that
|
|
FRAME_SAVED_PC() is being superseed by frame_pc_unwind() and that
|
|
function does have somewhere to cache that PC value. */
|
|
|
|
if (DEPRECATED_INIT_FRAME_PC_FIRST_P ())
|
|
prev->pc = (DEPRECATED_INIT_FRAME_PC_FIRST (fromleaf, prev));
|
|
|
|
if (INIT_EXTRA_FRAME_INFO_P ())
|
|
INIT_EXTRA_FRAME_INFO (fromleaf, prev);
|
|
|
|
/* This entry is in the frame queue now, which is good since
|
|
FRAME_SAVED_PC may use that queue to figure out its value (see
|
|
tm-sparc.h). We want the pc saved in the inferior frame. */
|
|
if (DEPRECATED_INIT_FRAME_PC_P ())
|
|
prev->pc = DEPRECATED_INIT_FRAME_PC (fromleaf, prev);
|
|
|
|
/* If ->frame and ->pc are unchanged, we are in the process of
|
|
getting ourselves into an infinite backtrace. Some architectures
|
|
check this in FRAME_CHAIN or thereabouts, but it seems like there
|
|
is no reason this can't be an architecture-independent check. */
|
|
if (prev->frame == next_frame->frame
|
|
&& prev->pc == next_frame->pc)
|
|
{
|
|
next_frame->prev = NULL;
|
|
obstack_free (&frame_cache_obstack, prev);
|
|
return NULL;
|
|
}
|
|
|
|
/* Initialize the code used to unwind the frame PREV based on the PC
|
|
(and probably other architectural information). The PC lets you
|
|
check things like the debug info at that point (dwarf2cfi?) and
|
|
use that to decide how the frame should be unwound. */
|
|
prev->unwind = frame_unwind_find_by_pc (current_gdbarch, prev->pc);
|
|
|
|
/* NOTE: cagney/2002-11-18: The code segments, found in
|
|
create_new_frame and get_prev_frame(), that initializes the
|
|
frames type is subtly different. The latter only updates ->type
|
|
when it encounters a SIGTRAMP_FRAME or DUMMY_FRAME. This stops
|
|
get_prev_frame() overriding the frame's type when the INIT code
|
|
has previously set it. This is really somewhat bogus. The
|
|
initialization, as seen in create_new_frame(), should occur
|
|
before the INIT function has been called. */
|
|
if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
|
|
&& (DEPRECATED_PC_IN_CALL_DUMMY_P ()
|
|
? DEPRECATED_PC_IN_CALL_DUMMY (prev->pc, 0, 0)
|
|
: pc_in_dummy_frame (prev->pc)))
|
|
prev->type = DUMMY_FRAME;
|
|
else
|
|
{
|
|
/* FIXME: cagney/2002-11-10: This should be moved to before the
|
|
INIT code above so that the INIT code knows what the frame's
|
|
type is (in fact, for a [generic] dummy-frame, the type can
|
|
be set and then the entire initialization can be skipped.
|
|
Unforunatly, its the INIT code that sets the PC (Hmm, catch
|
|
22). */
|
|
char *name;
|
|
find_pc_partial_function (prev->pc, &name, NULL, NULL);
|
|
if (PC_IN_SIGTRAMP (prev->pc, name))
|
|
prev->type = SIGTRAMP_FRAME;
|
|
/* FIXME: cagney/2002-11-11: Leave prev->type alone. Some
|
|
architectures are forcing the frame's type in INIT so we
|
|
don't want to override it here. Remember, NORMAL_FRAME == 0,
|
|
so it all works (just :-/). Once this initialization is
|
|
moved to the start of this function, all this nastness will
|
|
go away. */
|
|
}
|
|
|
|
return prev;
|
|
}
|
|
|
|
/* Return a structure containing various interesting information
|
|
about the frame that called NEXT_FRAME. Returns NULL
|
|
if there is no such frame. */
|
|
|
|
struct frame_info *
|
|
get_prev_frame (struct frame_info *next_frame)
|
|
{
|
|
struct frame_info *prev_frame;
|
|
|
|
/* Return the inner-most frame, when the caller passes in NULL. */
|
|
/* NOTE: cagney/2002-11-09: Not sure how this would happen. The
|
|
caller should have previously obtained a valid frame using
|
|
get_selected_frame() and then called this code - only possibility
|
|
I can think of is code behaving badly.
|
|
|
|
NOTE: cagney/2003-01-10: Talk about code behaving badly. Check
|
|
block_innermost_frame(). It does the sequence: frame = NULL;
|
|
while (1) { frame = get_prev_frame (frame); .... }. Ulgh! Why
|
|
it couldn't be written better, I don't know.
|
|
|
|
NOTE: cagney/2003-01-11: I suspect what is happening is
|
|
block_innermost_frame() is, when the target has no state
|
|
(registers, memory, ...), still calling this function. The
|
|
assumption being that this function will return NULL indicating
|
|
that a frame isn't possible, rather than checking that the target
|
|
has state and then calling get_current_frame() and
|
|
get_prev_frame(). This is a guess mind. */
|
|
if (next_frame == NULL)
|
|
{
|
|
/* NOTE: cagney/2002-11-09: There was a code segment here that
|
|
would error out when CURRENT_FRAME was NULL. The comment
|
|
that went with it made the claim ...
|
|
|
|
``This screws value_of_variable, which just wants a nice
|
|
clean NULL return from block_innermost_frame if there are no
|
|
frames. I don't think I've ever seen this message happen
|
|
otherwise. And returning NULL here is a perfectly legitimate
|
|
thing to do.''
|
|
|
|
Per the above, this code shouldn't even be called with a NULL
|
|
NEXT_FRAME. */
|
|
return current_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 (next_frame != NULL);
|
|
|
|
if (next_frame->level >= 0
|
|
&& !backtrace_below_main
|
|
&& inside_main_func (get_frame_pc (next_frame)))
|
|
/* Don't unwind past main(), bug always unwind the sentinel frame.
|
|
Note, this is done _before_ the frame has been marked as
|
|
previously unwound. That way if the user later decides to
|
|
allow unwinds past main(), that just happens. */
|
|
return NULL;
|
|
|
|
/* Only try to do the unwind once. */
|
|
if (next_frame->prev_p)
|
|
return next_frame->prev;
|
|
next_frame->prev_p = 1;
|
|
|
|
/* If we're inside the entry file, it isn't valid. */
|
|
/* NOTE: drow/2002-12-25: should there be a way to disable this
|
|
check? It assumes a single small entry file, and the way some
|
|
debug readers (e.g. dbxread) figure out which object is the
|
|
entry file is somewhat hokey. */
|
|
/* NOTE: cagney/2003-01-10: If there is a way of disabling this test
|
|
then it should probably be moved to before the ->prev_p test,
|
|
above. */
|
|
if (inside_entry_file (get_frame_pc (next_frame)))
|
|
return NULL;
|
|
|
|
/* If any of the old frame initialization methods are around, use
|
|
the legacy get_prev_frame method. Just don't try to unwind a
|
|
sentinel frame using that method - it doesn't work. All sentinal
|
|
frames use the new unwind code. */
|
|
if ((DEPRECATED_INIT_FRAME_PC_P ()
|
|
|| DEPRECATED_INIT_FRAME_PC_FIRST_P ()
|
|
|| INIT_EXTRA_FRAME_INFO_P ()
|
|
|| FRAME_CHAIN_P ())
|
|
&& next_frame->level >= 0)
|
|
return legacy_get_prev_frame (next_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 = next_frame->level + 1;
|
|
|
|
/* Try to unwind the PC. If that doesn't work, assume we've reached
|
|
the oldest frame and simply return. Is there a better sentinal
|
|
value? The unwound PC value is then used to initialize the new
|
|
previous frame's type.
|
|
|
|
Note that the pc-unwind is intentionally performed before the
|
|
frame chain. This is ok since, for old targets, both
|
|
frame_pc_unwind (nee, FRAME_SAVED_PC) and FRAME_CHAIN()) assume
|
|
NEXT_FRAME's data structures have already been initialized (using
|
|
INIT_EXTRA_FRAME_INFO) and hence the call order doesn't matter.
|
|
|
|
By unwinding the PC first, it becomes possible to, in the case of
|
|
a dummy frame, avoid also unwinding the frame ID. This is
|
|
because (well ignoring the PPC) a dummy frame can be located
|
|
using NEXT_FRAME's frame ID. */
|
|
|
|
prev_frame->pc = frame_pc_unwind (next_frame);
|
|
if (prev_frame->pc == 0)
|
|
/* The allocated PREV_FRAME will be reclaimed when the frame
|
|
obstack is next purged. */
|
|
return NULL;
|
|
prev_frame->type = frame_type_from_pc (prev_frame->pc);
|
|
|
|
/* Set the unwind functions based on that identified PC. */
|
|
prev_frame->unwind = frame_unwind_find_by_pc (current_gdbarch,
|
|
prev_frame->pc);
|
|
|
|
/* FIXME: cagney/2003-01-13: A dummy frame doesn't need to unwind
|
|
the frame ID because the frame ID comes from the previous frame.
|
|
The other frames do though. True? */
|
|
{
|
|
/* FIXME: cagney/2002-12-18: Instead of this hack, should just
|
|
save the frame ID directly. */
|
|
struct frame_id id = frame_id_unwind (next_frame);
|
|
if (!frame_id_p (id))
|
|
return NULL;
|
|
prev_frame->frame = id.base;
|
|
}
|
|
|
|
/* Link it in. */
|
|
next_frame->prev = prev_frame;
|
|
prev_frame->next = next_frame;
|
|
|
|
/* FIXME: cagney/2002-01-19: This call will go away. Instead of
|
|
initializing extra info, all frames will use the frame_cache
|
|
(passed to the unwind functions) to store additional frame info.
|
|
Unfortunatly legacy targets can't use legacy_get_prev_frame() to
|
|
unwind the sentinel frame and, consequently, are forced to take
|
|
this code path and rely on the below call to INIT_EXTR_FRAME_INFO
|
|
to initialize the inner-most frame. */
|
|
if (INIT_EXTRA_FRAME_INFO_P ())
|
|
{
|
|
gdb_assert (prev_frame->level == 0);
|
|
INIT_EXTRA_FRAME_INFO (0, prev_frame);
|
|
}
|
|
|
|
return prev_frame;
|
|
}
|
|
|
|
CORE_ADDR
|
|
get_frame_pc (struct frame_info *frame)
|
|
{
|
|
return frame->pc;
|
|
}
|
|
|
|
static int
|
|
pc_notcurrent (struct frame_info *frame)
|
|
{
|
|
/* 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. */
|
|
struct frame_info *next = get_next_frame (frame);
|
|
int notcurrent = (next != NULL && get_frame_type (next) == NORMAL_FRAME);
|
|
return notcurrent;
|
|
}
|
|
|
|
void
|
|
find_frame_sal (struct frame_info *frame, struct symtab_and_line *sal)
|
|
{
|
|
(*sal) = find_pc_line (frame->pc, pc_notcurrent (frame));
|
|
}
|
|
|
|
/* 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 fi->frame;
|
|
}
|
|
|
|
/* 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)
|
|
{
|
|
/* Some targets still don't use [generic] dummy frames. Catch them
|
|
here. */
|
|
if (!DEPRECATED_USE_GENERIC_DUMMY_FRAMES
|
|
&& deprecated_frame_in_dummy (frame))
|
|
return DUMMY_FRAME;
|
|
return frame->type;
|
|
}
|
|
|
|
void
|
|
deprecated_set_frame_type (struct frame_info *frame, enum frame_type type)
|
|
{
|
|
/* Arrrg! See comment in "frame.h". */
|
|
frame->type = type;
|
|
}
|
|
|
|
#ifdef FRAME_FIND_SAVED_REGS
|
|
/* XXX - deprecated. This is a compatibility function for targets
|
|
that do not yet implement FRAME_INIT_SAVED_REGS. */
|
|
/* Find the addresses in which registers are saved in FRAME. */
|
|
|
|
void
|
|
deprecated_get_frame_saved_regs (struct frame_info *frame,
|
|
struct frame_saved_regs *saved_regs_addr)
|
|
{
|
|
if (frame->saved_regs == NULL)
|
|
{
|
|
frame->saved_regs = (CORE_ADDR *)
|
|
frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS);
|
|
}
|
|
if (saved_regs_addr == NULL)
|
|
{
|
|
struct frame_saved_regs saved_regs;
|
|
FRAME_FIND_SAVED_REGS (frame, saved_regs);
|
|
memcpy (frame->saved_regs, &saved_regs, SIZEOF_FRAME_SAVED_REGS);
|
|
}
|
|
else
|
|
{
|
|
FRAME_FIND_SAVED_REGS (frame, *saved_regs_addr);
|
|
memcpy (frame->saved_regs, saved_regs_addr, SIZEOF_FRAME_SAVED_REGS);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
struct frame_extra_info *
|
|
get_frame_extra_info (struct frame_info *fi)
|
|
{
|
|
return fi->extra_info;
|
|
}
|
|
|
|
struct frame_extra_info *
|
|
frame_extra_info_zalloc (struct frame_info *fi, long size)
|
|
{
|
|
fi->extra_info = frame_obstack_zalloc (size);
|
|
return fi->extra_info;
|
|
}
|
|
|
|
void
|
|
deprecated_update_frame_pc_hack (struct frame_info *frame, CORE_ADDR pc)
|
|
{
|
|
/* See comment in "frame.h". */
|
|
gdb_assert (frame->next != NULL);
|
|
frame->pc = pc;
|
|
}
|
|
|
|
void
|
|
deprecated_update_frame_base_hack (struct frame_info *frame, CORE_ADDR base)
|
|
{
|
|
/* See comment in "frame.h". */
|
|
frame->frame = base;
|
|
}
|
|
|
|
void
|
|
deprecated_set_frame_saved_regs_hack (struct frame_info *frame,
|
|
CORE_ADDR *saved_regs)
|
|
{
|
|
frame->saved_regs = saved_regs;
|
|
}
|
|
|
|
void
|
|
deprecated_set_frame_extra_info_hack (struct frame_info *frame,
|
|
struct frame_extra_info *extra_info)
|
|
{
|
|
frame->extra_info = extra_info;
|
|
}
|
|
|
|
void
|
|
deprecated_set_frame_next_hack (struct frame_info *fi,
|
|
struct frame_info *next)
|
|
{
|
|
fi->next = next;
|
|
}
|
|
|
|
void
|
|
deprecated_set_frame_prev_hack (struct frame_info *fi,
|
|
struct frame_info *prev)
|
|
{
|
|
fi->prev = prev;
|
|
}
|
|
|
|
struct context *
|
|
deprecated_get_frame_context (struct frame_info *fi)
|
|
{
|
|
return fi->context;
|
|
}
|
|
|
|
void
|
|
deprecated_set_frame_context (struct frame_info *fi,
|
|
struct context *context)
|
|
{
|
|
fi->context = context;
|
|
}
|
|
|
|
struct frame_info *
|
|
deprecated_frame_xmalloc (void)
|
|
{
|
|
struct frame_info *frame = XMALLOC (struct frame_info);
|
|
memset (frame, 0, sizeof (struct frame_info));
|
|
return frame;
|
|
}
|
|
|
|
struct frame_info *
|
|
deprecated_frame_xmalloc_with_cleanup (long sizeof_saved_regs,
|
|
long sizeof_extra_info)
|
|
{
|
|
struct frame_info *frame = deprecated_frame_xmalloc ();
|
|
make_cleanup (xfree, frame);
|
|
if (sizeof_saved_regs > 0)
|
|
{
|
|
frame->saved_regs = xcalloc (1, sizeof_saved_regs);
|
|
make_cleanup (xfree, frame->saved_regs);
|
|
}
|
|
if (sizeof_extra_info > 0)
|
|
{
|
|
frame->extra_info = xcalloc (1, sizeof_extra_info);
|
|
make_cleanup (xfree, frame->extra_info);
|
|
}
|
|
return frame;
|
|
}
|
|
|
|
void
|
|
_initialize_frame (void)
|
|
{
|
|
obstack_init (&frame_cache_obstack);
|
|
|
|
/* FIXME: cagney/2003-01-19: This command needs a rename. Suggest
|
|
`set backtrace {past,beyond,...}-main'. Also suggest adding `set
|
|
backtrace ...-start' to control backtraces past start. The
|
|
problem with `below' is that it stops the `up' command. */
|
|
|
|
add_setshow_boolean_cmd ("backtrace-below-main", class_obscure,
|
|
&backtrace_below_main, "\
|
|
Set whether backtraces should continue past \"main\".\n\
|
|
Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
|
|
the backtrace at \"main\". Set this variable if you need to see the rest\n\
|
|
of the stack trace.", "\
|
|
Show whether backtraces should continue past \"main\".\n\
|
|
Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
|
|
the backtrace at \"main\". Set this variable if you need to see the rest\n\
|
|
of the stack trace.",
|
|
NULL, NULL, &setlist, &showlist);
|
|
}
|