/* Simulate breakpoints by patching locations in the target system, for GDB.
- Copyright 1990, 1991 Free Software Foundation, Inc.
+ Copyright 1990, 1991, 1995 Free Software Foundation, Inc.
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
-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 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.
+ 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., 675 Mass Ave, Cambridge, MA 02139, USA. */
+ 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"
-#ifdef BREAKPOINT
/* This file is only useful if BREAKPOINT is set. If not, we punt. */
-#include <stdio.h>
+#include "symtab.h"
#include "breakpoint.h"
#include "inferior.h"
#include "target.h"
-/* 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 char break_insn[] = BREAKPOINT;
+/* Use the program counter to determine the contents and size
+ of a breakpoint instruction. If no target-dependent macro
+ BREAKPOINT_FROM_PC has been defined to implement this function,
+ assume that the breakpoint doesn't depend on the PC, and
+ use the values of the BIG_BREAKPOINT and LITTLE_BREAKPOINT macros.
+ Return a pointer to a string of bytes that encode a breakpoint
+ instruction, stores the length of the string to *lenptr,
+ and optionally adjust the pc to point to the correct memory location
+ for inserting the breakpoint. */
-/* This is only to check that BREAKPOINT fits in BREAKPOINT_MAX bytes. */
+unsigned char *
+memory_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
+{
+ /* {BIG_,LITTLE_}BREAKPOINT 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. */
+#ifdef BIG_BREAKPOINT
+ if (TARGET_BYTE_ORDER == BIG_ENDIAN)
+ {
+ static unsigned char big_break_insn[] = BIG_BREAKPOINT;
+ *lenptr = sizeof (big_break_insn);
+ return big_break_insn;
+ }
+#endif
+#ifdef LITTLE_BREAKPOINT
+ if (TARGET_BYTE_ORDER != BIG_ENDIAN)
+ {
+ static unsigned char little_break_insn[] = LITTLE_BREAKPOINT;
+ *lenptr = sizeof (little_break_insn);
+ return little_break_insn;
+ }
+#endif
+#ifdef BREAKPOINT
+ {
+ static unsigned char break_insn[] = BREAKPOINT;
+ *lenptr = sizeof (break_insn);
+ return break_insn;
+ }
+#endif
+ *lenptr = 0;
+ return NULL;
+}
-static char check_break_insn_size[BREAKPOINT_MAX] = BREAKPOINT;
-/* Insert a breakpoint on machines 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,
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 sizeof BREAKPOINT bytes.
- FIXME: This size is target_arch dependent and should be available in
- the target_arch transfer vector, if we ever have one... */
+ 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;
+default_memory_insert_breakpoint (CORE_ADDR addr, char *contents_cache)
{
int val;
+ unsigned char *bp;
+ int bplen;
+
+ /* Determine appropriate breakpoint contents and size for this address. */
+ bp = BREAKPOINT_FROM_PC (&addr, &bplen);
+ if (bp == NULL)
+ error ("Software breakpoints not implemented for this target.");
- val = target_read_memory (addr, contents_cache, sizeof break_insn);
+ /* Save the memory contents. */
+ val = target_read_memory (addr, contents_cache, bplen);
+ /* Write the breakpoint. */
if (val == 0)
- val = target_write_memory (addr, break_insn, sizeof break_insn);
+ val = target_write_memory (addr, (char *) bp, bplen);
return val;
}
int
-memory_remove_breakpoint (addr, contents_cache)
- CORE_ADDR addr;
- char *contents_cache;
+default_memory_remove_breakpoint (CORE_ADDR addr, char *contents_cache)
{
- return target_write_memory (addr, contents_cache, sizeof break_insn);
-}
+ unsigned char *bp;
+ int bplen;
+ /* Determine appropriate breakpoint contents and size for this address. */
+ bp = BREAKPOINT_FROM_PC (&addr, &bplen);
+ if (bp == NULL)
+ error ("Software breakpoints not implemented for this target.");
-int memory_breakpoint_size = sizeof (break_insn);
-
-
-#else /* BREAKPOINT */
+ return target_write_memory (addr, contents_cache, bplen);
+}
-char nogo[] = "Breakpoints not implemented for this target.";
int
-memory_insert_breakpoint (addr, contents_cache)
- CORE_ADDR addr;
- char *contents_cache;
+memory_insert_breakpoint (CORE_ADDR addr, char *contents_cache)
{
- error (nogo);
- return 0; /* lint */
+ return MEMORY_INSERT_BREAKPOINT(addr, contents_cache);
}
int
-memory_remove_breakpoint (addr, contents_cache)
- CORE_ADDR addr;
- char *contents_cache;
+memory_remove_breakpoint (CORE_ADDR addr, char *contents_cache)
{
- error (nogo);
- return 0; /* lint */
+ return MEMORY_REMOVE_BREAKPOINT(addr, contents_cache);
}
-
-int memory_breakpoint_size = -1;
-
-#endif /* BREAKPOINT */
projects / deliverable / binutils-gdb.git / blobdiff