/* Target-dependent code for Renesas M32R, for GDB.
- Copyright 1996, 1998, 1999, 2000, 2001, 2002, 2003 Free Software
+ Copyright 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free Software
Foundation, Inc.
This file is part of GDB.
/* This is required by skip_prologue. The results of decoding a prologue
should be cached because this thrashing is getting nuts. */
-static void
+static int
decode_prologue (CORE_ADDR start_pc, CORE_ADDR scan_limit,
- CORE_ADDR *pl_endptr)
+ CORE_ADDR *pl_endptr, unsigned long *framelength)
{
unsigned long framesize;
int insn;
int op1;
- int maybe_one_more = 0;
CORE_ADDR after_prologue = 0;
+ CORE_ADDR after_push = 0;
CORE_ADDR after_stack_adjust = 0;
CORE_ADDR current_pc;
+ LONGEST return_value;
framesize = 0;
after_prologue = 0;
for (current_pc = start_pc; current_pc < scan_limit; current_pc += 2)
{
+ /* Check if current pc's location is readable. */
+ if (!safe_read_memory_integer (current_pc, 2, &return_value))
+ return -1;
+
insn = read_memory_unsigned_integer (current_pc, 2);
+ if (insn == 0x0000)
+ break;
+
/* If this is a 32 bit instruction, we dont want to examine its
immediate data as though it were an instruction */
if (current_pc & 0x02)
{
- /* Clear the parallel execution bit from 16 bit instruction */
- if (maybe_one_more)
- {
- /* The last instruction was a branch, usually terminates
- the series, but if this is a parallel instruction,
- it may be a stack framing instruction */
- if (!(insn & 0x8000))
- {
- /* nope, we are really done */
- break;
- }
- }
/* decode this instruction further */
insn &= 0x7fff;
}
else
{
- if (maybe_one_more)
- break; /* This isnt the one more */
if (insn & 0x8000)
{
if (current_pc == scan_limit)
scan_limit += 2; /* extend the search */
+
current_pc += 2; /* skip the immediate data */
+
+ /* Check if current pc's location is readable. */
+ if (!safe_read_memory_integer (current_pc, 2, &return_value))
+ return -1;
+
if (insn == 0x8faf) /* add3 sp, sp, xxxx */
/* add 16 bit sign-extended offset */
{
else
{
if (((insn >> 8) == 0xe4) /* ld24 r4, xxxxxx; sub sp, r4 */
+ && safe_read_memory_integer (current_pc + 2, 2,
+ &return_value)
&& read_memory_unsigned_integer (current_pc + 2,
2) == 0x0f24)
/* subtract 24 bit sign-extended negative-offset */
framesize += insn;
}
}
- after_prologue = current_pc;
+ after_push = current_pc + 2;
continue;
}
}
after_prologue = current_pc + 2;
break; /* end of stack adjustments */
}
+
/* Nop looks like a branch, continue explicitly */
if (insn == 0x7000)
{
after_prologue = current_pc + 2;
continue; /* nop occurs between pushes */
}
+ /* End of prolog if any of these are trap instructions */
+ if ((insn & 0xfff0) == 0x10f0)
+ {
+ after_prologue = current_pc;
+ break;
+ }
/* End of prolog if any of these are branch instructions */
if ((op1 == 0x7000) || (op1 == 0xb000) || (op1 == 0xf000))
{
after_prologue = current_pc;
- maybe_one_more = 1;
continue;
}
/* Some of the branch instructions are mixed with other types */
if ((subop == 0x0ec0) || (subop == 0x0fc0))
{
after_prologue = current_pc;
- maybe_one_more = 1;
continue; /* jmp , jl */
}
}
}
+ if (framelength)
+ *framelength = framesize;
+
if (current_pc >= scan_limit)
{
if (pl_endptr)
{
*pl_endptr = after_stack_adjust;
}
+ else if (after_push != 0)
+ /* We did not find a "mv fp,sp", but we DID find
+ a push. Is it safe to use that as the
+ end of the prologue? I just don't know. */
+ {
+ *pl_endptr = after_push;
+ }
else
/* We reached the end of the loop without finding the end
of the prologue. No way to win -- we should report failure.
GDB will set a breakpoint at the start of the function (etc.) */
*pl_endptr = start_pc;
}
- return;
+ return 0;
}
+
if (after_prologue == 0)
after_prologue = current_pc;
if (pl_endptr)
*pl_endptr = after_prologue;
+
+ return 0;
} /* decode_prologue */
/* Function: skip_prologue
Find end of function prologue */
-#define DEFAULT_SEARCH_LIMIT 44
+#define DEFAULT_SEARCH_LIMIT 128
CORE_ADDR
m32r_skip_prologue (CORE_ADDR pc)
{
CORE_ADDR func_addr, func_end;
struct symtab_and_line sal;
+ LONGEST return_value;
/* See what the symbol table says */
}
else
func_end = pc + DEFAULT_SEARCH_LIMIT;
- decode_prologue (pc, func_end, &sal.end);
+
+ /* If pc's location is not readable, just quit. */
+ if (!safe_read_memory_integer (pc, 4, &return_value))
+ return pc;
+
+ /* Find the end of prologue. */
+ if (decode_prologue (pc, func_end, &sal.end, NULL) < 0)
+ return pc;
+
return sal.end;
}
-
struct m32r_unwind_cache
{
/* The previous frame's inner most stack address. Used as this
m32r_frame_unwind_cache (struct frame_info *next_frame,
void **this_prologue_cache)
{
- CORE_ADDR pc;
+ CORE_ADDR pc, scan_limit;
ULONGEST prev_sp;
ULONGEST this_base;
- unsigned long op;
+ unsigned long op, op2;
int i;
struct m32r_unwind_cache *info;
+
if ((*this_prologue_cache))
return (*this_prologue_cache);
info->size = 0;
info->sp_offset = 0;
-
info->uses_frame = 0;
+
+ scan_limit = frame_pc_unwind (next_frame);
for (pc = frame_func_unwind (next_frame);
- pc > 0 && pc < frame_pc_unwind (next_frame); pc += 2)
+ pc > 0 && pc < scan_limit; pc += 2)
{
if ((pc & 2) == 0)
{
short n = op & 0xffff;
info->sp_offset += n;
}
- else if (((op >> 8) == 0xe4) /* ld24 r4, xxxxxx; sub sp, r4 */
- && get_frame_memory_unsigned (next_frame, pc + 4,
+ else if (((op >> 8) == 0xe4)
+ && get_frame_memory_unsigned (next_frame, pc + 2,
2) == 0x0f24)
{
+ /* ld24 r4, xxxxxx; sub sp, r4 */
unsigned long n = op & 0xffffff;
info->sp_offset += n;
- pc += 2;
+ pc += 2; /* skip sub instruction */
}
- else
- break;
- pc += 2;
+ if (pc == scan_limit)
+ scan_limit += 2; /* extend the search */
+ pc += 2; /* skip the immediate data */
continue;
}
}
/* mv fp, sp */
info->uses_frame = 1;
info->r13_offset = info->sp_offset;
+ break; /* end of stack adjustments */
+ }
+ else if ((op & 0xfff0) == 0x10f0)
+ {
+ /* end of prologue if this is a trap instruction */
+ break; /* end of stack adjustments */
}
- else if (op == 0x7000)
- /* nop */
- continue;
- else
- break;
}
info->size = -info->sp_offset;
projects / deliverable / binutils-gdb.git / commitdiff
