Fri Jan 3 14:20:05 1997 Geoffrey Noer <noer@cygnus.com>

* mn10300-tdep.c (mn10300_push_arguments): rewrote
        also removed code elsewhere that made use of RP_REGNUM
This commit is contained in:
Geoffrey Noer 1997-01-03 22:23:08 +00:00
parent 56f3b62cf5
commit 3de7693865
2 changed files with 353 additions and 5 deletions

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@ -1,3 +1,8 @@
Fri Jan 3 14:20:05 1997 Geoffrey Noer <noer@cygnus.com>
* mn10300-tdep.c (mn10300_push_arguments): rewrote
also removed code elsewhere that made use of RP_REGNUM
Tue Dec 31 15:19:32 1996 Geoffrey Noer <noer@cygnus.com> Tue Dec 31 15:19:32 1996 Geoffrey Noer <noer@cygnus.com>
* config/mn10300/tm-mn10300.h: more small register fixes * config/mn10300/tm-mn10300.h: more small register fixes

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@ -1,5 +1,5 @@
/* Target-dependent code for the NEC MN10300 for GDB, the GNU debugger. /* Target-dependent code for the Matsushita MN10300 for GDB, the GNU debugger.
Copyright 1996, Free Software Foundation, Inc. Copyright 1996, 1997 Free Software Foundation, Inc.
This file is part of GDB. This file is part of GDB.
@ -15,9 +15,7 @@ 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, Boston, MA 02111-1307, USA. */ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
/* Contributed by Geoffrey Noer, noer@cygnus.com */
#include "defs.h" #include "defs.h"
#include "frame.h" #include "frame.h"
@ -47,36 +45,259 @@ struct prologue_info
struct pifsr *pifsrs; struct pifsr *pifsrs;
}; };
static CORE_ADDR mn10300_scan_prologue PARAMS ((CORE_ADDR pc,
struct prologue_info *fs));
/* Function: scan_prologue
Scan the prologue of the function that contains PC, and record what
we find in PI. PI->fsr must be zeroed by the called. Returns the
pc after the prologue. Note that the addresses saved in pi->fsr
are actually just frame relative (negative offsets from the frame
pointer). This is because we don't know the actual value of the
frame pointer yet. In some circumstances, the frame pointer can't
be determined till after we have scanned the prologue. */
static CORE_ADDR static CORE_ADDR
mn10300_scan_prologue (pc, pi) mn10300_scan_prologue (pc, pi)
CORE_ADDR pc; CORE_ADDR pc;
struct prologue_info *pi; struct prologue_info *pi;
{ {
CORE_ADDR func_addr, prologue_end, current_pc;
struct pifsr *pifsr;
int fp_used;
printf("mn10300_scan_prologue start\n");
/* First, figure out the bounds of the prologue so that we can limit the
search to something reasonable. */
if (find_pc_partial_function (pc, NULL, &func_addr, NULL))
{
struct symtab_and_line sal;
sal = find_pc_line (func_addr, 0);
if (func_addr == entry_point_address ())
pi->start_function = 1;
else
pi->start_function = 0;
#if 0
if (sal.line == 0)
prologue_end = pc;
else
prologue_end = sal.end;
#else
prologue_end = pc;
#endif
}
else
{ /* We're in the boondocks */
func_addr = pc - 100;
prologue_end = pc;
}
prologue_end = min (prologue_end, pc);
/* Now, search the prologue looking for instructions that setup fp, save
rp, adjust sp and such. We also record the frame offset of any saved
registers. */
pi->frameoffset = 0;
pi->framereg = SP_REGNUM;
fp_used = 0;
pifsr = pi->pifsrs;
for (current_pc = func_addr; current_pc < prologue_end; current_pc += 2)
{
int insn;
insn = read_memory_unsigned_integer (current_pc, 2);
if ((insn & 0x07c0) == 0x0780 /* jarl or jr */
|| (insn & 0xffe0) == 0x0060 /* jmp */
|| (insn & 0x0780) == 0x0580) /* branch */
break; /* Ran into end of prologue */
if ((insn & 0xffe0) == ((SP_REGNUM << 11) | 0x0240)) /* add <imm>,sp */
pi->frameoffset = ((insn & 0x1f) ^ 0x10) - 0x10;
else if (insn == ((SP_REGNUM << 11) | 0x0600 | SP_REGNUM)) /* addi <imm>,sp,sp */
pi->frameoffset = read_memory_integer (current_pc + 2, 2);
else if (insn == ((FP_REGNUM << 11) | 0x0000 | 12)) /* mov r12,fp */
{
fp_used = 1;
pi->framereg = FP_REGNUM;
}
else if ((insn & 0x07ff) == (0x0760 | SP_REGNUM) /* st.w <reg>,<offset>[sp] */
|| (fp_used
&& (insn & 0x07ff) == (0x0760 | FP_REGNUM))) /* st.w <reg>,<offset>[fp] */
if (pifsr)
{
pifsr->framereg = insn & 0x1f;
pifsr->reg = (insn >> 11) & 0x1f; /* Extract <reg> */
pifsr->offset = read_memory_integer (current_pc + 2, 2) & ~1;
pifsr++;
}
if ((insn & 0x0780) >= 0x0600) /* Four byte instruction? */
current_pc += 2;
}
if (pifsr)
pifsr->framereg = 0; /* Tie off last entry */
printf("mn10300_scan_prologue end \n");
return current_pc;
} }
/* 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 scan_prologue().
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 mn10300_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 void
mn10300_init_extra_frame_info (fi) mn10300_init_extra_frame_info (fi)
struct frame_info *fi; struct frame_info *fi;
{ {
struct prologue_info pi;
struct pifsr pifsrs[NUM_REGS + 1], *pifsr;
int reg;
printf("mn10300_init_extra_frame_info start\n");
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;
mn10300_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("mn10300_init_extra_frame_info end\n");
} }
/* Function: frame_chain
Figure out the frame prior to FI. Unfortunately, this involves
scanning the prologue of the caller, which will also be done
shortly by mn10300_init_extra_frame_info. For the dummy frame, we
just return the stack pointer that was in use at the time the
function call was made. */
CORE_ADDR CORE_ADDR
mn10300_frame_chain (fi) mn10300_frame_chain (fi)
struct frame_info *fi; struct frame_info *fi;
{ {
struct prologue_info pi;
CORE_ADDR callers_pc, fp;
printf("mn10300_frame_chain start\n");
/* First, find out who called us */
callers_pc = FRAME_SAVED_PC (fi);
/* If caller is a call-dummy, then our FP bears no relation to his FP! */
fp = mn10300_find_callers_reg (fi, FP_REGNUM);
if (PC_IN_CALL_DUMMY(callers_pc, fp, fp))
return fp; /* caller is call-dummy: return oldest value of FP */
/* Caller is NOT a call-dummy, so everything else should just work.
Even if THIS frame is a call-dummy! */
pi.pifsrs = NULL;
mn10300_scan_prologue (callers_pc, &pi);
printf("mn10300_frame_chain end\n");
if (pi.start_function)
return 0; /* Don't chain beyond the start function */
if (pi.framereg == FP_REGNUM)
return mn10300_find_callers_reg (fi, pi.framereg);
return fi->frame - pi.frameoffset;
} }
/* 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 CORE_ADDR
mn10300_find_callers_reg (fi, regnum) mn10300_find_callers_reg (fi, regnum)
struct frame_info *fi; struct frame_info *fi;
int regnum; 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 code past the prologue of the function. */
CORE_ADDR CORE_ADDR
mn10300_skip_prologue (pc) mn10300_skip_prologue (pc)
CORE_ADDR 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 /* Function: pop_frame
@ -87,8 +308,35 @@ void
mn10300_pop_frame (frame) mn10300_pop_frame (frame)
struct frame_info *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 CORE_ADDR
mn10300_push_arguments (nargs, args, sp, struct_return, struct_addr) mn10300_push_arguments (nargs, args, sp, struct_return, struct_addr)
int nargs; int nargs;
@ -97,19 +345,89 @@ mn10300_push_arguments (nargs, args, sp, struct_return, struct_addr)
unsigned char struct_return; unsigned char struct_return;
CORE_ADDR struct_addr; 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 CORE_ADDR
mn10300_push_return_address (pc, sp) mn10300_push_return_address (pc, sp)
CORE_ADDR pc; CORE_ADDR pc;
CORE_ADDR sp; 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 CORE_ADDR
mn10300_frame_saved_pc (fi) mn10300_frame_saved_pc (fi)
struct frame_info *fi; struct frame_info *fi;
{ {
printf("mn10300_frame_saved_pc\n");
/* if (PC_IN_CALL_DUMMY(fi->pc, fi->frame, fi->frame)) */
return generic_read_register_dummy(fi->pc, fi->frame, PC_REGNUM);
/* else
return mn10300_find_callers_reg (fi, RP_REGNUM);
*/
} }
void void
@ -121,10 +439,19 @@ get_saved_register (raw_buffer, optimized, addrp, frame, regnum, lval)
int regnum; int regnum;
enum lval_type *lval; enum lval_type *lval;
{ {
printf("get_saved_register\n");
generic_get_saved_register (raw_buffer, optimized, addrp, generic_get_saved_register (raw_buffer, optimized, addrp,
frame, regnum, lval); frame, regnum, lval);
} }
/* Function: fix_call_dummy
Pokes the callee function's address into the CALL_DUMMY assembly stub.
Assumes that the CALL_DUMMY looks like this:
jarl <offset24>, r31
trap
*/
int int
mn10300_fix_call_dummy (dummy, sp, fun, nargs, args, type, gcc_p) mn10300_fix_call_dummy (dummy, sp, fun, nargs, args, type, gcc_p)
char *dummy; char *dummy;
@ -135,10 +462,26 @@ mn10300_fix_call_dummy (dummy, sp, fun, nargs, args, type, gcc_p)
struct type *type; struct type *type;
int gcc_p; int gcc_p;
{ {
long offset24;
printf("mn10300_fix_call_dummy start\n");
offset24 = (long) fun - (long) entry_point_address ();
offset24 &= 0x3fffff;
offset24 |= 0xff800000; /* jarl <offset24>, r31 */
store_unsigned_integer ((unsigned int *)&dummy[2], 2, offset24 & 0xffff);
store_unsigned_integer ((unsigned int *)&dummy[0], 2, offset24 >> 16);
printf("mn10300_fix_call_dummy end\n");
return 0;
} }
void void
_initialize_mn10300_tdep () _initialize_mn10300_tdep ()
{ {
printf("_initialize_mn10300_tdep\n");
tm_print_insn = print_insn_mn10300; tm_print_insn = print_insn_mn10300;
} }