-/* Target-dependent code for the NEC MN10300 for GDB, the GNU debugger.
- Copyright 1996, Free Software Foundation, Inc.
+/* Target-dependent code for the Matsushita MN10300 for GDB, the GNU debugger.
+ Copyright 1996, 1997 Free Software Foundation, Inc.
This file is part of GDB.
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. */
-
-/* Contributed by Geoffrey Noer, noer@cygnus.com */
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include "defs.h"
#include "frame.h"
struct pifsr *pifsrs;
};
-static CORE_ADDR
-mn10300_scan_prologue (pc, pi)
- CORE_ADDR pc;
- struct prologue_info *pi;
-{
-}
+/* Function: frame_chain
+ Figure out and return the caller's frame pointer given current
+ frame_info struct.
-void
-mn10300_init_extra_frame_info (fi)
- struct frame_info *fi;
-{
-}
+ We start out knowing the current pc, current sp, current fp.
+ We want to determine the caller's fp and caller's pc. To do this
+ correctly, we have to be able to handle the case where we are in the
+ middle of the prologue which involves scanning the prologue.
+
+ We don't handle dummy frames yet but we would probably just return the
+ stack pointer that was in use at the time the function call was made?
+*/
CORE_ADDR
mn10300_frame_chain (fi)
struct frame_info *fi;
{
+ struct prologue_info pi;
+ CORE_ADDR callers_pc, callers_fp, curr_sp;
+ CORE_ADDR past_prologue_addr;
+ int past_prologue = 1; /* default to being past prologue */
+ int n_movm_args = 4;
+
+ struct pifsr *pifsr, *pifsr_tmp;
+
+ /* current pc is fi->pc */
+ /* current fp is fi->frame */
+
+ /* current sp is: */
+ curr_sp = read_register (SP_REGNUM);
+
+/*
+ printf("curr pc = 0x%x ; curr fp = 0x%x ; curr sp = 0x%x\n",
+ fi->pc, fi->frame, curr_sp);
+*/
+
+ /* first inst after prologue is: */
+ past_prologue_addr = mn10300_skip_prologue (fi->pc);
+
+ /* Are we in the prologue? */
+ /* Yes if mn10300_skip_prologue returns an address after the
+ current pc in which case we have to scan prologue */
+ if (fi->pc < mn10300_skip_prologue (fi->pc))
+ past_prologue = 0;
+
+ /* scan prologue if we're not past it */
+ if (!past_prologue)
+ {
+ /* printf("scanning prologue\n"); */
+ /* FIXME -- fill out this case later */
+ return 0x0; /* bogus value */
+ }
+
+ if (past_prologue) /* if we don't need to scan the prologue */
+ {
+/* printf("we're past the prologue\n"); */
+ callers_pc = fi->frame - REGISTER_SIZE;
+ callers_fp = fi->frame - ((n_movm_args + 1) * REGISTER_SIZE);
+/*
+ printf("callers_pc = 0x%x ; callers_fp = 0x%x\n",
+ callers_pc, callers_fp);
+
+ printf("*callers_pc = 0x%x ; *callers_fp = 0x%x\n",
+ read_memory_integer(callers_pc, REGISTER_SIZE),
+ read_memory_integer(callers_fp, REGISTER_SIZE));
+*/
+ return read_memory_integer(callers_fp, REGISTER_SIZE);
+ }
+
+ /* we don't get here */
}
+/* Function: find_callers_reg
+ Find REGNUM on the stack. Otherwise, it's in an active register.
+ One thing we might want to do here is to check REGNUM against the
+ clobber mask, and somehow flag it as invalid if it isn't saved on
+ the stack somewhere. This would provide a graceful failure mode
+ when trying to get the value of caller-saves registers for an inner
+ frame. */
+
CORE_ADDR
mn10300_find_callers_reg (fi, regnum)
struct frame_info *fi;
int regnum;
{
+/* printf("mn10300_find_callers_reg\n"); */
+
+ for (; fi; fi = fi->next)
+ if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame))
+ return generic_read_register_dummy (fi->pc, fi->frame, regnum);
+ else if (fi->fsr.regs[regnum] != 0)
+ return read_memory_unsigned_integer (fi->fsr.regs[regnum],
+ REGISTER_RAW_SIZE(regnum));
+
+ return read_register (regnum);
}
+/* Function: skip_prologue
+ Return the address of the first inst past the prologue of the function.
+*/
+
CORE_ADDR
mn10300_skip_prologue (pc)
CORE_ADDR pc;
{
+ CORE_ADDR func_addr, func_end;
+
+/* printf("mn10300_skip_prologue\n"); */
+
+ /* See what the symbol table says */
+
+ if (find_pc_partial_function (pc, NULL, &func_addr, &func_end))
+ {
+ struct symtab_and_line sal;
+
+ sal = find_pc_line (func_addr, 0);
+
+ if (sal.line != 0 && sal.end < func_end)
+ return sal.end;
+ else
+ /* Either there's no line info, or the line after the prologue is after
+ the end of the function. In this case, there probably isn't a
+ prologue. */
+ return pc;
+ }
+
+/* We can't find the start of this function, so there's nothing we can do. */
+ return pc;
}
/* Function: pop_frame
mn10300_pop_frame (frame)
struct frame_info *frame;
{
+ int regnum;
+
+/* printf("mn10300_pop_frame start\n"); */
+
+ if (PC_IN_CALL_DUMMY(frame->pc, frame->frame, frame->frame))
+ generic_pop_dummy_frame ();
+ else
+ {
+ write_register (PC_REGNUM, FRAME_SAVED_PC (frame));
+
+ for (regnum = 0; regnum < NUM_REGS; regnum++)
+ if (frame->fsr.regs[regnum] != 0)
+ write_register (regnum,
+ read_memory_unsigned_integer (frame->fsr.regs[regnum],
+ REGISTER_RAW_SIZE(regnum)));
+
+ write_register (SP_REGNUM, FRAME_FP (frame));
+ }
+
+ flush_cached_frames ();
+
+/* printf("mn10300_pop_frame end\n"); */
}
+/* Function: push_arguments
+ Setup arguments for a call to the target. Arguments go in
+ order on the stack.
+*/
+
CORE_ADDR
mn10300_push_arguments (nargs, args, sp, struct_return, struct_addr)
int nargs;
unsigned char struct_return;
CORE_ADDR struct_addr;
{
+ int argnum = 0;
+ int len = 0;
+ int stack_offset = 0; /* copy args to this offset onto stack */
+
+/* printf("mn10300_push_arguments start\n"); */
+
+ /* First, just for safety, make sure stack is aligned */
+ sp &= ~3;
+
+ /* Now make space on the stack for the args. */
+ for (argnum = 0; argnum < nargs; argnum++)
+ len += ((TYPE_LENGTH(VALUE_TYPE(args[argnum])) + 3) & ~3);
+
+ sp -= len;
+
+ /* Push all arguments onto the stack. */
+ for (argnum = 0; argnum < nargs; argnum++)
+ {
+ int len;
+ char *val;
+
+ if (TYPE_CODE (VALUE_TYPE (*args)) == TYPE_CODE_STRUCT
+ && TYPE_LENGTH (VALUE_TYPE (*args)) > 8)
+ {
+ /* for now, pretend structs aren't special */
+ len = TYPE_LENGTH (VALUE_TYPE (*args));
+ val = (char *)VALUE_CONTENTS (*args);
+ }
+ else
+ {
+ len = TYPE_LENGTH (VALUE_TYPE (*args));
+ val = (char *)VALUE_CONTENTS (*args);
+ }
+
+ while (len > 0)
+ {
+ write_memory (sp + stack_offset, val, 4);
+
+ len -= 4;
+ val += 4;
+ stack_offset += 4;
+ }
+ args++;
+ }
+
+/* printf"mn10300_push_arguments end\n"); */
+
+ return sp;
}
+/* Function: push_return_address (pc)
+ Set up the return address for the inferior function call.
+ Needed for targets where we don't actually execute a JSR/BSR instruction */
+
CORE_ADDR
mn10300_push_return_address (pc, sp)
CORE_ADDR pc;
CORE_ADDR sp;
{
+/* printf("mn10300_push_return_address\n"); */
+
+ /* write_register (RP_REGNUM, CALL_DUMMY_ADDRESS ()); */
+ return sp;
}
+/* Function: frame_saved_pc
+ Find the caller of this frame. We do this by seeing if RP_REGNUM
+ is saved in the stack anywhere, otherwise we get it from the
+ registers. If the inner frame is a dummy frame, return its PC
+ instead of RP, because that's where "caller" of the dummy-frame
+ will be found. */
+
CORE_ADDR
mn10300_frame_saved_pc (fi)
struct frame_info *fi;
{
+/* printf("mn10300_frame_saved_pc\n"); */
+
+ return (read_memory_integer(fi->frame - REGISTER_SIZE, REGISTER_SIZE));
}
void
int regnum;
enum lval_type *lval;
{
+/* printf("get_saved_register\n"); */
+
generic_get_saved_register (raw_buffer, optimized, addrp,
frame, regnum, lval);
}
-int
-mn10300_fix_call_dummy (dummy, sp, fun, nargs, args, type, gcc_p)
- char *dummy;
- CORE_ADDR sp;
- CORE_ADDR fun;
- int nargs;
- value_ptr *args;
- struct type *type;
- int gcc_p;
+/* Function: init_extra_frame_info
+ Setup the frame's frame pointer, pc, and frame addresses for saved
+ registers. Most of the work is done in frame_chain().
+
+ Note that when we are called for the last frame (currently active frame),
+ that fi->pc and fi->frame will already be setup. However, fi->frame will
+ be valid only if this routine uses FP. For previous frames, fi-frame will
+ always be correct (since that is derived from v850_frame_chain ()).
+
+ We can be called with the PC in the call dummy under two circumstances.
+ First, during normal backtracing, second, while figuring out the frame
+ pointer just prior to calling the target function (see run_stack_dummy).
+*/
+
+void
+mn10300_init_extra_frame_info (fi)
+ struct frame_info *fi;
{
+ struct prologue_info pi;
+ struct pifsr pifsrs[NUM_REGS + 1], *pifsr;
+ int reg;
+
+ if (fi->next)
+ fi->pc = FRAME_SAVED_PC (fi->next);
+
+ memset (fi->fsr.regs, '\000', sizeof fi->fsr.regs);
+
+ /* The call dummy doesn't save any registers on the stack, so we can return
+ now. */
+/*
+ if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame))
+ return;
+
+ pi.pifsrs = pifsrs;
+*/
+
+ /* v850_scan_prologue (fi->pc, &pi); */
+/*
+ if (!fi->next && pi.framereg == SP_REGNUM)
+ fi->frame = read_register (pi.framereg) - pi.frameoffset;
+
+ for (pifsr = pifsrs; pifsr->framereg; pifsr++)
+ {
+ fi->fsr.regs[pifsr->reg] = pifsr->offset + fi->frame;
+
+ if (pifsr->framereg == SP_REGNUM)
+ fi->fsr.regs[pifsr->reg] += pi.frameoffset;
+ }
+*/
+/* printf("init_extra_frame_info\n"); */
}
void
_initialize_mn10300_tdep ()
{
+/* printf("_initialize_mn10300_tdep\n"); */
+
tm_print_insn = print_insn_mn10300;
}
+
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