/* Simulate breakpoints by patching locations in the target system, for GDB.
|
/* Simulate breakpoints by patching locations in the target system, for GDB.
|
Copyright 1990, 1991, 1995 Free Software Foundation, Inc.
|
Copyright 1990, 1991, 1995 Free Software Foundation, Inc.
|
Contributed by Cygnus Support. Written by John Gilmore.
|
Contributed by Cygnus Support. Written by John Gilmore.
|
|
|
This file is part of GDB.
|
This file is part of GDB.
|
|
|
This program is free software; you can redistribute it and/or modify
|
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
|
it under the terms of the GNU General Public License as published by
|
the Free Software Foundation; either version 2 of the License, or
|
the Free Software Foundation; either version 2 of the License, or
|
(at your option) any later version.
|
(at your option) any later version.
|
|
|
This program is distributed in the hope that it will be useful,
|
This program is distributed in the hope that it will be useful,
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
GNU General Public License for more details.
|
GNU General Public License for more details.
|
|
|
You should have received a copy of the GNU General Public License
|
You should have received a copy of the GNU General Public License
|
along with this program; if not, write to the Free Software
|
along with this program; if not, write to the Free Software
|
Foundation, Inc., 59 Temple Place - Suite 330,
|
Foundation, Inc., 59 Temple Place - Suite 330,
|
Boston, MA 02111-1307, USA. */
|
Boston, MA 02111-1307, USA. */
|
|
|
#include "defs.h"
|
#include "defs.h"
|
|
|
/* This file is only useful if BREAKPOINT is set. If not, we punt. */
|
/* This file is only useful if BREAKPOINT is set. If not, we punt. */
|
|
|
#include "symtab.h"
|
#include "symtab.h"
|
#include "breakpoint.h"
|
#include "breakpoint.h"
|
#include "inferior.h"
|
#include "inferior.h"
|
#include "target.h"
|
#include "target.h"
|
|
|
|
|
/* Use the program counter to determine the contents and size
|
/* Use the program counter to determine the contents and size
|
of a breakpoint instruction. If no target-dependent macro
|
of a breakpoint instruction. If no target-dependent macro
|
BREAKPOINT_FROM_PC has been defined to implement this function,
|
BREAKPOINT_FROM_PC has been defined to implement this function,
|
assume that the breakpoint doesn't depend on the PC, and
|
assume that the breakpoint doesn't depend on the PC, and
|
use the values of the BIG_BREAKPOINT and LITTLE_BREAKPOINT macros.
|
use the values of the BIG_BREAKPOINT and LITTLE_BREAKPOINT macros.
|
Return a pointer to a string of bytes that encode a breakpoint
|
Return a pointer to a string of bytes that encode a breakpoint
|
instruction, stores the length of the string to *lenptr,
|
instruction, stores the length of the string to *lenptr,
|
and optionally adjust the pc to point to the correct memory location
|
and optionally adjust the pc to point to the correct memory location
|
for inserting the breakpoint. */
|
for inserting the breakpoint. */
|
|
|
unsigned char *
|
unsigned char *
|
memory_breakpoint_from_pc (pcptr, lenptr)
|
memory_breakpoint_from_pc (pcptr, lenptr)
|
CORE_ADDR *pcptr;
|
CORE_ADDR *pcptr;
|
int *lenptr;
|
int *lenptr;
|
{
|
{
|
/* {BIG_,LITTLE_}BREAKPOINT is the sequence of bytes we insert for a
|
/* {BIG_,LITTLE_}BREAKPOINT is the sequence of bytes we insert for a
|
breakpoint. On some machines, breakpoints are handled by the
|
breakpoint. On some machines, breakpoints are handled by the
|
target environment and we don't have to worry about them here. */
|
target environment and we don't have to worry about them here. */
|
#ifdef BIG_BREAKPOINT
|
#ifdef BIG_BREAKPOINT
|
if (TARGET_BYTE_ORDER == BIG_ENDIAN)
|
if (TARGET_BYTE_ORDER == BIG_ENDIAN)
|
{
|
{
|
static unsigned char big_break_insn[] = BIG_BREAKPOINT;
|
static unsigned char big_break_insn[] = BIG_BREAKPOINT;
|
*lenptr = sizeof (big_break_insn);
|
*lenptr = sizeof (big_break_insn);
|
return big_break_insn;
|
return big_break_insn;
|
}
|
}
|
#endif
|
#endif
|
#ifdef LITTLE_BREAKPOINT
|
#ifdef LITTLE_BREAKPOINT
|
if (TARGET_BYTE_ORDER != BIG_ENDIAN)
|
if (TARGET_BYTE_ORDER != BIG_ENDIAN)
|
{
|
{
|
static unsigned char little_break_insn[] = LITTLE_BREAKPOINT;
|
static unsigned char little_break_insn[] = LITTLE_BREAKPOINT;
|
*lenptr = sizeof (little_break_insn);
|
*lenptr = sizeof (little_break_insn);
|
return little_break_insn;
|
return little_break_insn;
|
}
|
}
|
#endif
|
#endif
|
#ifdef BREAKPOINT
|
#ifdef BREAKPOINT
|
{
|
{
|
static unsigned char break_insn[] = BREAKPOINT;
|
static unsigned char break_insn[] = BREAKPOINT;
|
*lenptr = sizeof (break_insn);
|
*lenptr = sizeof (break_insn);
|
return break_insn;
|
return break_insn;
|
}
|
}
|
#endif
|
#endif
|
*lenptr = 0;
|
*lenptr = 0;
|
return NULL;
|
return NULL;
|
}
|
}
|
|
|
|
|
/* Insert a breakpoint on targets that don't have any better breakpoint
|
/* Insert a breakpoint on targets that don't have any better breakpoint
|
support. We read the contents of the target location and stash it,
|
support. We read the contents of the target location and stash it,
|
then overwrite it with a breakpoint instruction. ADDR is the target
|
then overwrite it with a breakpoint instruction. ADDR is the target
|
location in the target machine. CONTENTS_CACHE is a pointer to
|
location in the target machine. CONTENTS_CACHE is a pointer to
|
memory allocated for saving the target contents. It is guaranteed
|
memory allocated for saving the target contents. It is guaranteed
|
by the caller to be long enough to save BREAKPOINT_LEN bytes (this
|
by the caller to be long enough to save BREAKPOINT_LEN bytes (this
|
is accomplished via BREAKPOINT_MAX). */
|
is accomplished via BREAKPOINT_MAX). */
|
|
|
int
|
int
|
default_memory_insert_breakpoint (addr, contents_cache)
|
default_memory_insert_breakpoint (addr, contents_cache)
|
CORE_ADDR addr;
|
CORE_ADDR addr;
|
char *contents_cache;
|
char *contents_cache;
|
{
|
{
|
int val;
|
int val;
|
unsigned char *bp;
|
unsigned char *bp;
|
int bplen;
|
int bplen;
|
|
|
/* Determine appropriate breakpoint contents and size for this address. */
|
/* Determine appropriate breakpoint contents and size for this address. */
|
bp = BREAKPOINT_FROM_PC (&addr, &bplen);
|
bp = BREAKPOINT_FROM_PC (&addr, &bplen);
|
if (bp == NULL)
|
if (bp == NULL)
|
error ("Software breakpoints not implemented for this target.");
|
error ("Software breakpoints not implemented for this target.");
|
|
|
/* Save the memory contents. */
|
/* Save the memory contents. */
|
val = target_read_memory (addr, contents_cache, bplen);
|
val = target_read_memory (addr, contents_cache, bplen);
|
|
|
/* Write the breakpoint. */
|
/* Write the breakpoint. */
|
if (val == 0)
|
if (val == 0)
|
val = target_write_memory (addr, (char *) bp, bplen);
|
val = target_write_memory (addr, (char *) bp, bplen);
|
|
|
return val;
|
return val;
|
}
|
}
|
|
|
|
|
int
|
int
|
default_memory_remove_breakpoint (addr, contents_cache)
|
default_memory_remove_breakpoint (addr, contents_cache)
|
CORE_ADDR addr;
|
CORE_ADDR addr;
|
char *contents_cache;
|
char *contents_cache;
|
{
|
{
|
unsigned char *bp;
|
unsigned char *bp;
|
int bplen;
|
int bplen;
|
|
|
/* Determine appropriate breakpoint contents and size for this address. */
|
/* Determine appropriate breakpoint contents and size for this address. */
|
bp = BREAKPOINT_FROM_PC (&addr, &bplen);
|
bp = BREAKPOINT_FROM_PC (&addr, &bplen);
|
if (bp == NULL)
|
if (bp == NULL)
|
error ("Software breakpoints not implemented for this target.");
|
error ("Software breakpoints not implemented for this target.");
|
|
|
return target_write_memory (addr, contents_cache, bplen);
|
return target_write_memory (addr, contents_cache, bplen);
|
}
|
}
|
|
|
|
|
#if !defined(MEMORY_INSERT_BREAKPOINT)
|
#if !defined(MEMORY_INSERT_BREAKPOINT)
|
#define MEMORY_INSERT_BREAKPOINT(addr, contents_cache) \
|
#define MEMORY_INSERT_BREAKPOINT(addr, contents_cache) \
|
default_memory_insert_breakpoint(addr, contents_cache)
|
default_memory_insert_breakpoint(addr, contents_cache)
|
#endif
|
#endif
|
int
|
int
|
memory_insert_breakpoint (addr, contents_cache)
|
memory_insert_breakpoint (addr, contents_cache)
|
CORE_ADDR addr;
|
CORE_ADDR addr;
|
char *contents_cache;
|
char *contents_cache;
|
{
|
{
|
return MEMORY_INSERT_BREAKPOINT(addr, contents_cache);
|
return MEMORY_INSERT_BREAKPOINT(addr, contents_cache);
|
}
|
}
|
|
|
#if !defined(MEMORY_REMOVE_BREAKPOINT)
|
#if !defined(MEMORY_REMOVE_BREAKPOINT)
|
#define MEMORY_REMOVE_BREAKPOINT(addr, contents_cache) \
|
#define MEMORY_REMOVE_BREAKPOINT(addr, contents_cache) \
|
default_memory_remove_breakpoint(addr, contents_cache)
|
default_memory_remove_breakpoint(addr, contents_cache)
|
#endif
|
#endif
|
int
|
int
|
memory_remove_breakpoint (addr, contents_cache)
|
memory_remove_breakpoint (addr, contents_cache)
|
CORE_ADDR addr;
|
CORE_ADDR addr;
|
char *contents_cache;
|
char *contents_cache;
|
{
|
{
|
return MEMORY_REMOVE_BREAKPOINT(addr, contents_cache);
|
return MEMORY_REMOVE_BREAKPOINT(addr, contents_cache);
|
}
|
}
|
|
|
