NetBSD/gnu/dist/gdb6/gdb/sentinel-frame.c

103 lines
3.2 KiB
C

/* Code dealing with register stack frames, for GDB, the GNU debugger.
Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002 Free Software
Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include "defs.h"
#include "regcache.h"
#include "sentinel-frame.h"
#include "inferior.h"
#include "frame-unwind.h"
struct frame_unwind_cache
{
struct regcache *regcache;
};
void *
sentinel_frame_cache (struct regcache *regcache)
{
struct frame_unwind_cache *cache =
FRAME_OBSTACK_ZALLOC (struct frame_unwind_cache);
cache->regcache = regcache;
return cache;
}
/* Here the register value is taken direct from the register cache. */
static void
sentinel_frame_prev_register (struct frame_info *next_frame,
void **this_prologue_cache,
int regnum, int *optimized,
enum lval_type *lvalp, CORE_ADDR *addrp,
int *realnum, gdb_byte *bufferp)
{
struct frame_unwind_cache *cache = *this_prologue_cache;
/* Describe the register's location. A reg-frame maps all registers
onto the corresponding hardware register. */
*optimized = 0;
*lvalp = lval_register;
*addrp = register_offset_hack (current_gdbarch, regnum);
*realnum = regnum;
/* If needed, find and return the value of the register. */
if (bufferp != NULL)
{
/* Return the actual value. */
/* Use the regcache_cooked_read() method so that it, on the fly,
constructs either a raw or pseudo register from the raw
register cache. */
regcache_cooked_read (cache->regcache, regnum, bufferp);
}
}
static void
sentinel_frame_this_id (struct frame_info *next_frame,
void **this_prologue_cache,
struct frame_id *this_id)
{
/* The sentinel frame is used as a starting point for creating the
previous (inner most) frame. That frame's THIS_ID method will be
called to determine the inner most frame's ID. Not this one. */
internal_error (__FILE__, __LINE__, _("sentinel_frame_this_id called"));
}
static CORE_ADDR
sentinel_frame_prev_pc (struct frame_info *next_frame,
void **this_prologue_cache)
{
struct gdbarch *gdbarch = get_frame_arch (next_frame);
return gdbarch_unwind_pc (gdbarch, next_frame);
}
const struct frame_unwind sentinel_frame_unwinder =
{
SENTINEL_FRAME,
sentinel_frame_this_id,
sentinel_frame_prev_register,
NULL, /* unwind_data */
NULL, /* sniffer */
sentinel_frame_prev_pc,
};
const struct frame_unwind *const sentinel_frame_unwind = &sentinel_frame_unwinder;