Retro68/binutils/opcodes/i370-dis.c
2012-03-26 21:18:29 +02:00

162 lines
5.5 KiB
C

/* i370-dis.c -- Disassemble Instruction 370 (ESA/390) instructions
Copyright 1994, 2000, 2003, 2005, 2007 Free Software Foundation, Inc.
PowerPC version written by Ian Lance Taylor, Cygnus Support
Rewritten for i370 ESA/390 support by Linas Vepstas <linas@linas.org>
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 file; see the file COPYING. If not, write to the Free
Software Foundation, 51 Franklin Street - Fifth Floor, Boston,
MA 02110-1301, USA. */
#include <stdio.h>
#include "sysdep.h"
#include "dis-asm.h"
#include "opcode/i370.h"
/* This file provides several disassembler functions, all of which use
the disassembler interface defined in dis-asm.h. */
int
print_insn_i370 (bfd_vma memaddr, struct disassemble_info *info)
{
bfd_byte buffer[8];
int status;
i370_insn_t insn;
const struct i370_opcode *opcode;
const struct i370_opcode *opcode_end;
status = (*info->read_memory_func) (memaddr, buffer, 6, info);
if (status != 0)
{
(*info->memory_error_func) (status, memaddr, info);
return -1;
}
/* Cast the bytes into the insn (in a host-endian indep way). */
insn.i[0] = (buffer[0] << 24) & 0xff000000;
insn.i[0] |= (buffer[1] << 16) & 0xff0000;
insn.i[0] |= (buffer[2] << 8) & 0xff00;
insn.i[0] |= buffer[3] & 0xff;
insn.i[1] = (buffer[4] << 24) & 0xff000000;
insn.i[1] |= (buffer[5] << 16) & 0xff0000;
/* Find the first match in the opcode table. We could speed this up
a bit by doing a binary search on the major opcode. */
opcode_end = i370_opcodes + i370_num_opcodes;
for (opcode = i370_opcodes; opcode < opcode_end; opcode++)
{
const unsigned char *opindex;
const struct i370_operand *operand;
i370_insn_t masked;
int invalid;
/* Mask off operands, and look for a match ... */
masked = insn;
if (2 == opcode->len)
{
masked.i[0] >>= 16;
masked.i[0] &= 0xffff;
}
masked.i[0] &= opcode->mask.i[0];
if (masked.i[0] != opcode->opcode.i[0])
continue;
if (6 == opcode->len)
{
masked.i[1] &= opcode->mask.i[1];
if (masked.i[1] != opcode->opcode.i[1])
continue;
}
/* Found a match. adjust a tad. */
if (2 == opcode->len)
{
insn.i[0] >>= 16;
insn.i[0] &= 0xffff;
}
/* Make two passes over the operands. First see if any of them
have extraction functions, and, if they do, make sure the
instruction is valid. */
invalid = 0;
for (opindex = opcode->operands; *opindex != 0; opindex++)
{
operand = i370_operands + *opindex;
if (operand->extract)
(*operand->extract) (insn, &invalid);
}
if (invalid)
continue;
/* The instruction is valid. */
(*info->fprintf_func) (info->stream, "%s", opcode->name);
if (opcode->operands[0] != 0)
(*info->fprintf_func) (info->stream, "\t");
/* Now extract and print the operands. */
for (opindex = opcode->operands; *opindex != 0; opindex++)
{
long value;
operand = i370_operands + *opindex;
/* Extract the value from the instruction. */
if (operand->extract)
value = (*operand->extract) (insn, (int *) NULL);
else
value = (insn.i[0] >> operand->shift) & ((1 << operand->bits) - 1);
/* Print the operand as directed by the flags. */
if ((operand->flags & I370_OPERAND_OPTIONAL) != 0)
{
if (value)
(*info->fprintf_func) (info->stream, "(r%ld)", value);
}
else if ((operand->flags & I370_OPERAND_SBASE) != 0)
{
(*info->fprintf_func) (info->stream, "(r%ld)", value);
}
else if ((operand->flags & I370_OPERAND_INDEX) != 0)
{
if (value)
(*info->fprintf_func) (info->stream, "(r%ld,", value);
else
(*info->fprintf_func) (info->stream, "(,");
}
else if ((operand->flags & I370_OPERAND_LENGTH) != 0)
{
(*info->fprintf_func) (info->stream, "(%ld,", value);
}
else if ((operand->flags & I370_OPERAND_BASE) != 0)
(*info->fprintf_func) (info->stream, "r%ld)", value);
else if ((operand->flags & I370_OPERAND_GPR) != 0)
(*info->fprintf_func) (info->stream, "r%ld,", value);
else if ((operand->flags & I370_OPERAND_FPR) != 0)
(*info->fprintf_func) (info->stream, "f%ld,", value);
else if ((operand->flags & I370_OPERAND_RELATIVE) != 0)
(*info->fprintf_func) (info->stream, "%ld", value);
else
(*info->fprintf_func) (info->stream, " %ld, ", value);
}
return opcode->len;
}
/* We could not find a match. */
(*info->fprintf_func) (info->stream, ".short 0x%02x%02x", buffer[0], buffer[1]);
return 2;
}