122 lines
3.5 KiB
C
122 lines
3.5 KiB
C
/* Simulate breakpoints by patching locations in the target system, for GDB.
|
|
Copyright 1990, 1991, 1995 Free Software Foundation, Inc.
|
|
Contributed by Cygnus Support. Written by John Gilmore.
|
|
|
|
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"
|
|
|
|
/* Either BREAKPOINT should be defined, or both of LITTLE_BREAKPOINT,
|
|
BIG_BREAKPOINT should be defined. */
|
|
|
|
#if defined (BREAKPOINT) || (defined (LITTLE_BREAKPOINT) && defined (BIG_BREAKPOINT))
|
|
|
|
/* This file is only useful if BREAKPOINT is set. If not, we punt. */
|
|
|
|
#include "symtab.h"
|
|
#include "breakpoint.h"
|
|
#include "inferior.h"
|
|
#include "target.h"
|
|
|
|
/* If the target isn't bi-endian, just pretend it is. */
|
|
#if defined(BREAKPOINT) && !defined (LITTLE_BREAKPOINT) && !defined (BIG_BREAKPOINT)
|
|
#define LITTLE_BREAKPOINT BREAKPOINT
|
|
#define BIG_BREAKPOINT BREAKPOINT
|
|
#endif
|
|
|
|
/* This is the sequence of bytes we insert for a breakpoint. On some
|
|
machines, breakpoints are handled by the target environment and we
|
|
don't have to worry about them here. */
|
|
|
|
static unsigned char big_break_insn[] = BIG_BREAKPOINT;
|
|
static unsigned char little_break_insn[] = LITTLE_BREAKPOINT;
|
|
|
|
/* FIXME: We assume big and little breakpoints are the same size. */
|
|
#define BREAKPOINT_LEN (sizeof (big_break_insn))
|
|
|
|
/* Insert a breakpoint on targets that don't have any better breakpoint
|
|
support. We read the contents of the target location and stash it,
|
|
then overwrite it with a breakpoint instruction. ADDR is the target
|
|
location in the target machine. CONTENTS_CACHE is a pointer to
|
|
memory allocated for saving the target contents. It is guaranteed
|
|
by the caller to be long enough to save BREAKPOINT_LEN bytes (this
|
|
is accomplished via BREAKPOINT_MAX). */
|
|
|
|
int
|
|
memory_insert_breakpoint (addr, contents_cache)
|
|
CORE_ADDR addr;
|
|
char *contents_cache;
|
|
{
|
|
int val;
|
|
|
|
val = target_read_memory (addr, contents_cache, BREAKPOINT_LEN);
|
|
|
|
if (val == 0)
|
|
{
|
|
if (TARGET_BYTE_ORDER == BIG_ENDIAN)
|
|
val = target_write_memory (addr, (char *)big_break_insn,
|
|
BREAKPOINT_LEN);
|
|
else
|
|
val = target_write_memory (addr, (char *)little_break_insn,
|
|
BREAKPOINT_LEN);
|
|
}
|
|
|
|
return val;
|
|
}
|
|
|
|
|
|
int
|
|
memory_remove_breakpoint (addr, contents_cache)
|
|
CORE_ADDR addr;
|
|
char *contents_cache;
|
|
{
|
|
return target_write_memory (addr, contents_cache, BREAKPOINT_LEN);
|
|
}
|
|
|
|
|
|
/* FIXME: This is a hack and should depend on the debugging target.
|
|
See comment in breakpoint.c where this is used. */
|
|
|
|
int memory_breakpoint_size = BREAKPOINT_LEN;
|
|
|
|
|
|
#else /* BREAKPOINT */
|
|
|
|
char nogo[] = "Breakpoints not implemented for this target.";
|
|
|
|
int
|
|
memory_insert_breakpoint (addr, contents_cache)
|
|
CORE_ADDR addr;
|
|
char *contents_cache;
|
|
{
|
|
error (nogo);
|
|
return 0; /* lint */
|
|
}
|
|
|
|
int
|
|
memory_remove_breakpoint (addr, contents_cache)
|
|
CORE_ADDR addr;
|
|
char *contents_cache;
|
|
{
|
|
error (nogo);
|
|
return 0; /* lint */
|
|
}
|
|
|
|
int memory_breakpoint_size = -1;
|
|
|
|
#endif /* BREAKPOINT */
|