491 lines
14 KiB
C
491 lines
14 KiB
C
/* Print VAX instructions.
|
|
Copyright (C) 1995-2017 Free Software Foundation, Inc.
|
|
Contributed by Pauline Middelink <middelin@polyware.iaf.nl>
|
|
|
|
This file is part of the GNU opcodes library.
|
|
|
|
This library 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 3, or (at your option)
|
|
any later version.
|
|
|
|
It 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., 51 Franklin Street - Fifth Floor, Boston,
|
|
MA 02110-1301, USA. */
|
|
|
|
#include "sysdep.h"
|
|
#include <setjmp.h>
|
|
#include <string.h>
|
|
#include "opcode/vax.h"
|
|
#include "disassemble.h"
|
|
|
|
static char *reg_names[] =
|
|
{
|
|
"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
|
|
"r8", "r9", "r10", "r11", "ap", "fp", "sp", "pc"
|
|
};
|
|
|
|
/* Definitions for the function entry mask bits. */
|
|
static char *entry_mask_bit[] =
|
|
{
|
|
/* Registers 0 and 1 shall not be saved, since they're used to pass back
|
|
a function's result to its caller... */
|
|
"~r0~", "~r1~",
|
|
/* Registers 2 .. 11 are normal registers. */
|
|
"r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11",
|
|
/* Registers 12 and 13 are argument and frame pointer and must not
|
|
be saved by using the entry mask. */
|
|
"~ap~", "~fp~",
|
|
/* Bits 14 and 15 control integer and decimal overflow. */
|
|
"IntOvfl", "DecOvfl",
|
|
};
|
|
|
|
/* Sign-extend an (unsigned char). */
|
|
#define COERCE_SIGNED_CHAR(ch) ((signed char)(ch))
|
|
|
|
/* 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
|
|
|
|
struct private
|
|
{
|
|
/* Points to first byte not fetched. */
|
|
bfd_byte * max_fetched;
|
|
bfd_byte the_buffer[MAXLEN];
|
|
bfd_vma insn_start;
|
|
OPCODES_SIGJMP_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 (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);
|
|
OPCODES_SIGLONGJMP (priv->bailout, 1);
|
|
}
|
|
else
|
|
priv->max_fetched = addr;
|
|
|
|
return 1;
|
|
}
|
|
|
|
/* Entry mask handling. */
|
|
static unsigned int entry_addr_occupied_slots = 0;
|
|
static unsigned int entry_addr_total_slots = 0;
|
|
static bfd_vma * entry_addr = NULL;
|
|
|
|
/* Parse the VAX specific disassembler options. These contain function
|
|
entry addresses, which can be useful to disassemble ROM images, since
|
|
there's no symbol table. Returns TRUE upon success, FALSE otherwise. */
|
|
|
|
static bfd_boolean
|
|
parse_disassembler_options (const char *options)
|
|
{
|
|
const char * entry_switch = "entry:";
|
|
|
|
while ((options = strstr (options, entry_switch)))
|
|
{
|
|
options += strlen (entry_switch);
|
|
|
|
/* The greater-than part of the test below is paranoia. */
|
|
if (entry_addr_occupied_slots >= entry_addr_total_slots)
|
|
{
|
|
/* A guesstimate of the number of entries we will have to create. */
|
|
entry_addr_total_slots +=
|
|
strlen (options) / (strlen (entry_switch) + 5);
|
|
|
|
entry_addr = realloc (entry_addr, sizeof (bfd_vma)
|
|
* entry_addr_total_slots);
|
|
}
|
|
|
|
if (entry_addr == NULL)
|
|
return FALSE;
|
|
|
|
entry_addr[entry_addr_occupied_slots] = bfd_scan_vma (options, NULL, 0);
|
|
entry_addr_occupied_slots ++;
|
|
}
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
#if 0 /* FIXME: Ideally the disassembler should have target specific
|
|
initialisation and termination function pointers. Then
|
|
parse_disassembler_options could be the init function and
|
|
free_entry_array (below) could be the termination routine.
|
|
Until then there is no way for the disassembler to tell us
|
|
that it has finished and that we no longer need the entry
|
|
array, so this routine is suppressed for now. It does mean
|
|
that we leak memory, but only to the extent that we do not
|
|
free it just before the disassembler is about to terminate
|
|
anyway. */
|
|
|
|
/* Free memory allocated to our entry array. */
|
|
|
|
static void
|
|
free_entry_array (void)
|
|
{
|
|
if (entry_addr)
|
|
{
|
|
free (entry_addr);
|
|
entry_addr = NULL;
|
|
entry_addr_occupied_slots = entry_addr_total_slots = 0;
|
|
}
|
|
}
|
|
#endif
|
|
/* Check if the given address is a known function entry point. This is
|
|
the case if there is a symbol of the function type at this address.
|
|
We also check for synthetic symbols as these are used for PLT entries
|
|
(weak undefined symbols may not have the function type set). Finally
|
|
the address may have been forced to be treated as an entry point. The
|
|
latter helps in disassembling ROM images, because there's no symbol
|
|
table at all. Forced entry points can be given by supplying several
|
|
-M options to objdump: -M entry:0xffbb7730. */
|
|
|
|
static bfd_boolean
|
|
is_function_entry (struct disassemble_info *info, bfd_vma addr)
|
|
{
|
|
unsigned int i;
|
|
|
|
/* Check if there's a function or PLT symbol at our address. */
|
|
if (info->symbols
|
|
&& info->symbols[0]
|
|
&& (info->symbols[0]->flags & (BSF_FUNCTION | BSF_SYNTHETIC))
|
|
&& addr == bfd_asymbol_value (info->symbols[0]))
|
|
return TRUE;
|
|
|
|
/* Check for forced function entry address. */
|
|
for (i = entry_addr_occupied_slots; i--;)
|
|
if (entry_addr[i] == addr)
|
|
return TRUE;
|
|
|
|
return FALSE;
|
|
}
|
|
|
|
/* Check if the given address is the last longword of a PLT entry.
|
|
This longword is data and depending on the value it may interfere
|
|
with disassembly of further PLT entries. We make use of the fact
|
|
PLT symbols are marked BSF_SYNTHETIC. */
|
|
static bfd_boolean
|
|
is_plt_tail (struct disassemble_info *info, bfd_vma addr)
|
|
{
|
|
if (info->symbols
|
|
&& info->symbols[0]
|
|
&& (info->symbols[0]->flags & BSF_SYNTHETIC)
|
|
&& addr == bfd_asymbol_value (info->symbols[0]) + 8)
|
|
return TRUE;
|
|
|
|
return FALSE;
|
|
}
|
|
|
|
static int
|
|
print_insn_mode (const char *d,
|
|
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. */
|
|
if (d[1] == 'd' || d[1] == 'f' || d[1] == 'g' || d[1] == 'h')
|
|
(*info->fprintf_func) (info->stream, "$0x%x [%c-float]", mode, d[1]);
|
|
else
|
|
(*info->fprintf_func) (info->stream, "$0x%x", mode);
|
|
break;
|
|
case 0x40: /* Index: base-addr[Rn] */
|
|
p += print_insn_mode (d, 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");
|
|
if (d[1] == 'd' || d[1] == 'f' || d[1] == 'g' || d[1] == 'h')
|
|
{
|
|
int float_word;
|
|
|
|
float_word = p[0] | (p[1] << 8);
|
|
if ((d[1] == 'd' || d[1] == 'f')
|
|
&& (float_word & 0xff80) == 0x8000)
|
|
{
|
|
(*info->fprintf_func) (info->stream, "[invalid %c-float]",
|
|
d[1]);
|
|
}
|
|
else
|
|
{
|
|
for (i = 0; i < size; i++)
|
|
(*info->fprintf_func) (info->stream, "%02x",
|
|
p[size - i - 1]);
|
|
(*info->fprintf_func) (info->stream, " [%c-float]", d[1]);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
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, "*");
|
|
/* Fall through. */
|
|
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, "*");
|
|
/* Fall through. */
|
|
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, "*");
|
|
/* Fall through. */
|
|
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;
|
|
}
|
|
|
|
/* 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 (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 (d, arg_len, p0, addr, info);
|
|
}
|
|
|
|
/* Print the vax instruction at address MEMADDR in debugged memory,
|
|
on INFO->STREAM. Returns length of the instruction, in bytes. */
|
|
|
|
int
|
|
print_insn_vax (bfd_vma memaddr, disassemble_info *info)
|
|
{
|
|
static bfd_boolean parsed_disassembler_options = FALSE;
|
|
const struct vot *votp;
|
|
const char *argp;
|
|
unsigned char *arg;
|
|
struct private priv;
|
|
bfd_byte *buffer = priv.the_buffer;
|
|
|
|
info->private_data = & priv;
|
|
priv.max_fetched = priv.the_buffer;
|
|
priv.insn_start = memaddr;
|
|
|
|
if (! parsed_disassembler_options
|
|
&& info->disassembler_options != NULL)
|
|
{
|
|
parse_disassembler_options (info->disassembler_options);
|
|
|
|
/* To avoid repeated parsing of these options. */
|
|
parsed_disassembler_options = TRUE;
|
|
}
|
|
|
|
if (OPCODES_SIGSETJMP (priv.bailout) != 0)
|
|
/* Error return. */
|
|
return -1;
|
|
|
|
argp = NULL;
|
|
/* Check if the info buffer has more than one byte left since
|
|
the last opcode might be a single byte with no argument data. */
|
|
if (info->buffer_length - (memaddr - info->buffer_vma) > 1
|
|
&& (info->stop_vma == 0 || memaddr < (info->stop_vma - 1)))
|
|
{
|
|
FETCH_DATA (info, buffer + 2);
|
|
}
|
|
else
|
|
{
|
|
FETCH_DATA (info, buffer + 1);
|
|
buffer[1] = 0;
|
|
}
|
|
|
|
/* Decode function entry mask. */
|
|
if (is_function_entry (info, memaddr))
|
|
{
|
|
int i = 0;
|
|
int register_mask = buffer[1] << 8 | buffer[0];
|
|
|
|
(*info->fprintf_func) (info->stream, ".word 0x%04x # Entry mask: <",
|
|
register_mask);
|
|
|
|
for (i = 15; i >= 0; i--)
|
|
if (register_mask & (1 << i))
|
|
(*info->fprintf_func) (info->stream, " %s", entry_mask_bit[i]);
|
|
|
|
(*info->fprintf_func) (info->stream, " >");
|
|
|
|
return 2;
|
|
}
|
|
|
|
/* Decode PLT entry offset longword. */
|
|
if (is_plt_tail (info, memaddr))
|
|
{
|
|
int offset;
|
|
|
|
FETCH_DATA (info, buffer + 4);
|
|
offset = buffer[3] << 24 | buffer[2] << 16 | buffer[1] << 8 | buffer[0];
|
|
(*info->fprintf_func) (info->stream, ".long 0x%08x", offset);
|
|
|
|
return 4;
|
|
}
|
|
|
|
for (votp = &votstrs[0]; votp->name[0]; votp++)
|
|
{
|
|
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;
|
|
}
|
|
|