binutils-gdb/gdb/ns32k-tdep.c

245 lines
6.5 KiB
C
Raw Normal View History

/* Print NS 32000 instructions for GDB, the GNU debugger.
2001-03-06 09:22:02 +01:00
Copyright 1986, 1988, 1991, 1992, 1994, 1995, 1998, 1999, 2000, 2001
Free Software Foundation, Inc.
1999-07-07 22:19:36 +02:00
This file is part of GDB.
1999-07-07 22:19:36 +02:00
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.
1999-07-07 22:19:36 +02:00
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.
1999-07-07 22:19:36 +02:00
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"
#include "frame.h"
2001-03-28 23:26:07 +02:00
#include "gdbcore.h"
static int sign_extend (int value, int bits);
void
2000-07-30 03:48:28 +02:00
_initialize_ns32k_tdep (void)
{
tm_print_insn = print_insn_ns32k;
}
1999-05-05 16:45:51 +02:00
/* Advance PC across any function entry prologue instructions
to reach some "real" code. */
/* OBSOLETE CORE_ADDR */
/* OBSOLETE merlin_skip_prologue (CORE_ADDR pc) */
/* OBSOLETE { */
/* OBSOLETE register int op = read_memory_integer (pc, 1); */
/* OBSOLETE if (op == 0x82) */
/* OBSOLETE { */
/* OBSOLETE op = read_memory_integer (pc + 2, 1); */
/* OBSOLETE if ((op & 0x80) == 0) */
/* OBSOLETE pc += 3; */
/* OBSOLETE else if ((op & 0xc0) == 0x80) */
/* OBSOLETE pc += 4; */
/* OBSOLETE else */
/* OBSOLETE pc += 6; */
/* OBSOLETE } */
/* OBSOLETE return pc; */
/* OBSOLETE } */
1999-05-05 16:45:51 +02:00
CORE_ADDR
2000-07-30 03:48:28 +02:00
umax_skip_prologue (CORE_ADDR pc)
1999-05-05 16:45:51 +02:00
{
register unsigned char op = read_memory_integer (pc, 1);
if (op == 0x82)
{
1999-07-07 22:19:36 +02:00
op = read_memory_integer (pc + 2, 1);
1999-05-05 16:45:51 +02:00
if ((op & 0x80) == 0)
pc += 3;
else if ((op & 0xc0) == 0x80)
pc += 4;
else
pc += 6;
1999-07-07 22:19:36 +02:00
}
1999-05-05 16:45:51 +02:00
return pc;
}
1999-05-25 20:09:09 +02:00
/* Return number of args passed to a frame.
Can return -1, meaning no way to tell. */
/* OBSOLETE int */
/* OBSOLETE merlin_frame_num_args (struct frame_info *fi) */
/* OBSOLETE { */
/* OBSOLETE int numargs; */
/* OBSOLETE CORE_ADDR pc; */
/* OBSOLETE int insn; */
/* OBSOLETE int addr_mode; */
/* OBSOLETE int width; */
/* OBSOLETE */
/* OBSOLETE pc = FRAME_SAVED_PC (fi); */
/* OBSOLETE insn = read_memory_integer (pc, 2); */
/* OBSOLETE addr_mode = (insn >> 11) & 0x1f; */
/* OBSOLETE insn = insn & 0x7ff; */
/* OBSOLETE if ((insn & 0x7fc) == 0x57c */
/* OBSOLETE && addr_mode == 0x14) *//* immediate */
/* OBSOLETE { */
/* OBSOLETE if (insn == 0x57c) *//* adjspb */
/* OBSOLETE width = 1; */
/* OBSOLETE else if (insn == 0x57d) *//* adjspw */
/* OBSOLETE width = 2; */
/* OBSOLETE else if (insn == 0x57f) *//* adjspd */
/* OBSOLETE width = 4; */
/* OBSOLETE else */
/* OBSOLETE internal_error (__FILE__, __LINE__, "bad else"); */
/* OBSOLETE numargs = read_memory_integer (pc + 2, width); */
/* OBSOLETE if (width > 1) */
/* OBSOLETE flip_bytes (&numargs, width); */
/* OBSOLETE numargs = -sign_extend (numargs, width * 8) / 4; */
/* OBSOLETE } */
/* OBSOLETE else */
/* OBSOLETE numargs = -1; */
/* OBSOLETE return numargs; */
/* OBSOLETE } */
1999-06-07 21:19:32 +02:00
/* Return number of args passed to a frame.
Can return -1, meaning no way to tell.
Encore's C compiler often reuses same area on stack for args,
so this will often not work properly. If the arg names
are known, it's likely most of them will be printed. */
1999-05-25 20:09:09 +02:00
int
2000-07-30 03:48:28 +02:00
umax_frame_num_args (struct frame_info *fi)
1999-05-25 20:09:09 +02:00
{
int numargs;
CORE_ADDR pc;
CORE_ADDR enter_addr;
unsigned int insn;
unsigned int addr_mode;
int width;
numargs = -1;
enter_addr = ns32k_get_enter_addr ((fi)->pc);
if (enter_addr > 0)
{
pc = ((enter_addr == 1)
? SAVED_PC_AFTER_CALL (fi)
: FRAME_SAVED_PC (fi));
1999-07-07 22:19:36 +02:00
insn = read_memory_integer (pc, 2);
1999-05-25 20:09:09 +02:00
addr_mode = (insn >> 11) & 0x1f;
insn = insn & 0x7ff;
if ((insn & 0x7fc) == 0x57c
1999-07-07 22:19:36 +02:00
&& addr_mode == 0x14) /* immediate */
1999-05-25 20:09:09 +02:00
{
1999-07-07 22:19:36 +02:00
if (insn == 0x57c) /* adjspb */
1999-05-25 20:09:09 +02:00
width = 1;
1999-07-07 22:19:36 +02:00
else if (insn == 0x57d) /* adjspw */
1999-05-25 20:09:09 +02:00
width = 2;
1999-07-07 22:19:36 +02:00
else if (insn == 0x57f) /* adjspd */
1999-05-25 20:09:09 +02:00
width = 4;
2001-03-28 23:26:07 +02:00
else
internal_error (__FILE__, __LINE__, "bad else");
1999-07-07 22:19:36 +02:00
numargs = read_memory_integer (pc + 2, width);
1999-05-25 20:09:09 +02:00
if (width > 1)
flip_bytes (&numargs, width);
1999-07-07 22:19:36 +02:00
numargs = -sign_extend (numargs, width * 8) / 4;
1999-05-25 20:09:09 +02:00
}
}
return numargs;
}
1999-05-05 16:45:51 +02:00
2001-03-28 23:26:07 +02:00
static int
2000-07-30 03:48:28 +02:00
sign_extend (int value, int bits)
{
value = value & ((1 << bits) - 1);
1999-07-07 22:19:36 +02:00
return (value & (1 << (bits - 1))
? value | (~((1 << bits) - 1))
: value);
}
void
2001-03-28 23:26:07 +02:00
flip_bytes (void *p, int count)
{
char tmp;
2001-03-28 23:26:07 +02:00
char *ptr = 0;
while (count > 0)
{
tmp = *ptr;
1999-07-07 22:19:36 +02:00
ptr[0] = ptr[count - 1];
ptr[count - 1] = tmp;
ptr++;
count -= 2;
}
}
/* Return the number of locals in the current frame given a pc
pointing to the enter instruction. This is used in the macro
FRAME_FIND_SAVED_REGS. */
int
2000-07-30 03:48:28 +02:00
ns32k_localcount (CORE_ADDR enter_pc)
{
unsigned char localtype;
int localcount;
1999-07-07 22:19:36 +02:00
localtype = read_memory_integer (enter_pc + 2, 1);
if ((localtype & 0x80) == 0)
localcount = localtype;
else if ((localtype & 0xc0) == 0x80)
localcount = (((localtype & 0x3f) << 8)
1999-07-07 22:19:36 +02:00
| (read_memory_integer (enter_pc + 3, 1) & 0xff));
else
localcount = (((localtype & 0x3f) << 24)
1999-07-07 22:19:36 +02:00
| ((read_memory_integer (enter_pc + 3, 1) & 0xff) << 16)
| ((read_memory_integer (enter_pc + 4, 1) & 0xff) << 8)
| (read_memory_integer (enter_pc + 5, 1) & 0xff));
return localcount;
}
/* Nonzero if instruction at PC is a return instruction. */
static int
2000-07-30 03:48:28 +02:00
ns32k_about_to_return (CORE_ADDR pc)
{
return (read_memory_integer (pc, 1) == 0x12);
}
/*
* Get the address of the enter opcode for the function
* containing PC, if there is an enter for the function,
* and if the pc is between the enter and exit.
* Returns positive address if pc is between enter/exit,
* 1 if pc before enter or after exit, 0 otherwise.
*/
CORE_ADDR
2000-07-30 03:48:28 +02:00
ns32k_get_enter_addr (CORE_ADDR pc)
{
CORE_ADDR enter_addr;
unsigned char op;
if (pc == 0)
return 0;
if (ns32k_about_to_return (pc))
1999-07-07 22:19:36 +02:00
return 1; /* after exit */
enter_addr = get_pc_function_start (pc);
1999-07-07 22:19:36 +02:00
if (pc == enter_addr)
return 1; /* before enter */
op = read_memory_integer (enter_addr, 1);
if (op != 0x82)
1999-07-07 22:19:36 +02:00
return 0; /* function has no enter/exit */
1999-07-07 22:19:36 +02:00
return enter_addr; /* pc is between enter and exit */
}