darling-gdb/opcodes/vax-dis.c

301 lines
8.3 KiB
C

/* Print VAX instructions.
Copyright (C) 1995, 1998 Free Software Foundation, Inc.
Contributed by Pauline Middelink <middelin@polyware.iaf.nl>
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.
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 "sysdep.h"
#include "opcode/vax.h"
#include "dis-asm.h"
/* Local function prototypes */
static int
print_insn_arg PARAMS ((const char *, unsigned char *, bfd_vma,
disassemble_info *));
static int
print_insn_mode PARAMS ((int, unsigned char *, bfd_vma, disassemble_info *));
static char *reg_names[] =
{
"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
"r8", "r9", "r10", "r11", "ap", "fp", "sp", "pc"
};
/* Sign-extend an (unsigned char). */
#if __STDC__ == 1
#define COERCE_SIGNED_CHAR(ch) ((signed char)(ch))
#else
#define COERCE_SIGNED_CHAR(ch) ((int)(((ch) ^ 0x80) & 0xFF) - 128)
#endif
/* Get a 1 byte signed integer. */
#define NEXTBYTE(p) \
(p += 1, FETCH_DATA (info, p), \
COERCE_SIGNED_CHAR(p[-1]))
/* Get a 2 byte signed integer. */
#define COERCE16(x) ((int) (((x) ^ 0x8000) - 0x8000))
#define NEXTWORD(p) \
(p += 2, FETCH_DATA (info, p), \
COERCE16 ((p[-1] << 8) + p[-2]))
/* Get a 4 byte signed integer. */
#define COERCE32(x) ((int) (((x) ^ 0x80000000) - 0x80000000))
#define NEXTLONG(p) \
(p += 4, FETCH_DATA (info, p), \
(COERCE32 ((((((p[-1] << 8) + p[-2]) << 8) + p[-3]) << 8) + p[-4])))
/* Maximum length of an instruction. */
#define MAXLEN 25
#include <setjmp.h>
struct private
{
/* Points to first byte not fetched. */
bfd_byte *max_fetched;
bfd_byte the_buffer[MAXLEN];
bfd_vma insn_start;
jmp_buf bailout;
};
/* Make sure that bytes from INFO->PRIVATE_DATA->BUFFER (inclusive)
to ADDR (exclusive) are valid. Returns 1 for success, longjmps
on error. */
#define FETCH_DATA(info, addr) \
((addr) <= ((struct private *)(info->private_data))->max_fetched \
? 1 : fetch_data ((info), (addr)))
static int
fetch_data (info, addr)
struct disassemble_info *info;
bfd_byte *addr;
{
int status;
struct private *priv = (struct private *) info->private_data;
bfd_vma start = priv->insn_start + (priv->max_fetched - priv->the_buffer);
status = (*info->read_memory_func) (start,
priv->max_fetched,
addr - priv->max_fetched,
info);
if (status != 0)
{
(*info->memory_error_func) (status, start, info);
longjmp (priv->bailout, 1);
}
else
priv->max_fetched = addr;
return 1;
}
/* Print the vax instruction at address MEMADDR in debugged memory,
on INFO->STREAM. Returns length of the instruction, in bytes. */
int
print_insn_vax (memaddr, info)
bfd_vma memaddr;
disassemble_info *info;
{
const struct vot *votp;
const char *argp = NULL;
unsigned char *arg;
struct private priv;
bfd_byte *buffer = priv.the_buffer;
info->private_data = (PTR) &priv;
priv.max_fetched = priv.the_buffer;
priv.insn_start = memaddr;
if (setjmp (priv.bailout) != 0)
{
/* Error return. */
return -1;
}
FETCH_DATA (info, buffer + 2);
for (votp = &votstrs[0]; votp->name[0]; votp++)
{
register vax_opcodeT opcode = votp->detail.code;
/* 2 byte codes match 2 buffer pos. */
if ((bfd_byte) opcode == buffer[0]
&& (opcode >> 8 == 0 || opcode >> 8 == buffer[1]))
{
argp = votp->detail.args;
break;
}
}
if (argp == NULL)
{
/* Handle undefined instructions. */
(*info->fprintf_func) (info->stream, ".word 0x%x",
(buffer[0] << 8) + buffer[1]);
return 2;
}
/* Point at first byte of argument data, and at descriptor for first
argument. */
arg = buffer + ((votp->detail.code >> 8) ? 2 : 1);
/* Make sure we have it in mem */
FETCH_DATA (info, arg);
(*info->fprintf_func) (info->stream, "%s", votp->name);
if (*argp)
(*info->fprintf_func) (info->stream, " ");
while (*argp)
{
arg += print_insn_arg (argp, arg, memaddr + arg - buffer, info);
argp += 2;
if (*argp)
(*info->fprintf_func) (info->stream, ",");
}
return arg - buffer;
}
/* Returns number of bytes "eaten" by the operand, or return -1 if an
invalid operand was found, or -2 if an opcode tabel error was
found. */
static int
print_insn_arg (d, p0, addr, info)
const char *d;
unsigned char *p0;
bfd_vma addr; /* PC for this arg to be relative to */
disassemble_info *info;
{
int arg_len;
/* check validity of addressing length */
switch (d[1])
{
case 'b' : arg_len = 1; break;
case 'd' : arg_len = 8; break;
case 'f' : arg_len = 4; break;
case 'g' : arg_len = 8; break;
case 'h' : arg_len = 16; break;
case 'l' : arg_len = 4; break;
case 'o' : arg_len = 16; break;
case 'w' : arg_len = 2; break;
case 'q' : arg_len = 8; break;
default : abort();
}
/* branches have no mode byte */
if (d[0] == 'b')
{
unsigned char *p = p0;
if (arg_len == 1)
(*info->print_address_func) (addr + 1 + NEXTBYTE (p), info);
else
(*info->print_address_func) (addr + 2 + NEXTWORD (p), info);
return p - p0;
}
return print_insn_mode (arg_len, p0, addr, info);
}
static int
print_insn_mode (size, p0, addr, info)
int size;
unsigned char *p0;
bfd_vma addr; /* PC for this arg to be relative to */
disassemble_info *info;
{
unsigned char *p = p0;
unsigned char mode, reg;
/* fetch and interpret mode byte */
mode = (unsigned char) NEXTBYTE (p);
reg = mode & 0xF;
switch (mode & 0xF0)
{
case 0x00:
case 0x10:
case 0x20:
case 0x30: /* literal mode $number */
(*info->fprintf_func) (info->stream, "$0x%x", mode);
break;
case 0x40: /* index: base-addr[Rn] */
p += print_insn_mode (size, p0 + 1, addr + 1, info);
(*info->fprintf_func) (info->stream, "[%s]", reg_names[reg]);
break;
case 0x50: /* register: Rn */
(*info->fprintf_func) (info->stream, "%s", reg_names[reg]);
break;
case 0x60: /* register deferred: (Rn) */
(*info->fprintf_func) (info->stream, "(%s)", reg_names[reg]);
break;
case 0x70: /* autodecrement: -(Rn) */
(*info->fprintf_func) (info->stream, "-(%s)", reg_names[reg]);
break;
case 0x80: /* autoincrement: (Rn)+ */
if (reg == 0xF)
{ /* immediate? */
int i;
FETCH_DATA (info, p + size);
(*info->fprintf_func) (info->stream, "$0x");
for (i = 0; i < size; i++)
(*info->fprintf_func) (info->stream, "%02x", p[size - i - 1]);
p += size;
}
else
(*info->fprintf_func) (info->stream, "(%s)+", reg_names[reg]);
break;
case 0x90: /* autoincrement deferred: @(Rn)+ */
if (reg == 0xF)
(*info->fprintf_func) (info->stream, "*0x%x", NEXTLONG (p));
else
(*info->fprintf_func) (info->stream, "@(%s)+", reg_names[reg]);
break;
case 0xB0: /* displacement byte deferred: *displ(Rn) */
(*info->fprintf_func) (info->stream, "*");
case 0xA0: /* displacement byte: displ(Rn) */
if (reg == 0xF)
(*info->print_address_func) (addr + 2 + NEXTBYTE (p), info);
else
(*info->fprintf_func) (info->stream, "0x%x(%s)", NEXTBYTE (p),
reg_names[reg]);
break;
case 0xD0: /* displacement word deferred: *displ(Rn) */
(*info->fprintf_func) (info->stream, "*");
case 0xC0: /* displacement word: displ(Rn) */
if (reg == 0xF)
(*info->print_address_func) (addr + 3 + NEXTWORD (p), info);
else
(*info->fprintf_func) (info->stream, "0x%x(%s)", NEXTWORD (p),
reg_names[reg]);
break;
case 0xF0: /* displacement long deferred: *displ(Rn) */
(*info->fprintf_func) (info->stream, "*");
case 0xE0: /* displacement long: displ(Rn) */
if (reg == 0xF)
(*info->print_address_func) (addr + 5 + NEXTLONG (p), info);
else
(*info->fprintf_func) (info->stream, "0x%x(%s)", NEXTLONG (p),
reg_names[reg]);
break;
}
return p - p0;
}