binutils-gdb/opcodes/alpha-dis.c

208 lines
6.2 KiB
C

/* alpha-dis.c -- Disassemble Alpha AXP instructions
Copyright (C) 1996-2020 Free Software Foundation, Inc.
Contributed by Richard Henderson <rth@tamu.edu>,
patterned after the PPC opcode handling written by Ian Lance Taylor.
This file is part of libopcodes.
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 "sysdep.h"
#include <stdio.h>
#include "disassemble.h"
#include "opcode/alpha.h"
/* OSF register names. */
static const char * const osf_regnames[64] = {
"v0", "t0", "t1", "t2", "t3", "t4", "t5", "t6",
"t7", "s0", "s1", "s2", "s3", "s4", "s5", "fp",
"a0", "a1", "a2", "a3", "a4", "a5", "t8", "t9",
"t10", "t11", "ra", "t12", "at", "gp", "sp", "zero",
"$f0", "$f1", "$f2", "$f3", "$f4", "$f5", "$f6", "$f7",
"$f8", "$f9", "$f10", "$f11", "$f12", "$f13", "$f14", "$f15",
"$f16", "$f17", "$f18", "$f19", "$f20", "$f21", "$f22", "$f23",
"$f24", "$f25", "$f26", "$f27", "$f28", "$f29", "$f30", "$f31"
};
/* VMS register names. */
static const char * const vms_regnames[64] = {
"R0", "R1", "R2", "R3", "R4", "R5", "R6", "R7",
"R8", "R9", "R10", "R11", "R12", "R13", "R14", "R15",
"R16", "R17", "R18", "R19", "R20", "R21", "R22", "R23",
"R24", "AI", "RA", "PV", "AT", "FP", "SP", "RZ",
"F0", "F1", "F2", "F3", "F4", "F5", "F6", "F7",
"F8", "F9", "F10", "F11", "F12", "F13", "F14", "F15",
"F16", "F17", "F18", "F19", "F20", "F21", "F22", "F23",
"F24", "F25", "F26", "F27", "F28", "F29", "F30", "FZ"
};
/* Disassemble Alpha instructions. */
int
print_insn_alpha (bfd_vma memaddr, struct disassemble_info *info)
{
static const struct alpha_opcode *opcode_index[AXP_NOPS+1];
const char * const * regnames;
const struct alpha_opcode *opcode, *opcode_end;
const unsigned char *opindex;
unsigned insn, op, isa_mask;
int need_comma;
/* Initialize the majorop table the first time through */
if (!opcode_index[0])
{
opcode = alpha_opcodes;
opcode_end = opcode + alpha_num_opcodes;
for (op = 0; op < AXP_NOPS; ++op)
{
opcode_index[op] = opcode;
while (opcode < opcode_end && op == AXP_OP (opcode->opcode))
++opcode;
}
opcode_index[op] = opcode;
}
if (info->flavour == bfd_target_evax_flavour)
regnames = vms_regnames;
else
regnames = osf_regnames;
isa_mask = AXP_OPCODE_NOPAL;
switch (info->mach)
{
case bfd_mach_alpha_ev4:
isa_mask |= AXP_OPCODE_EV4;
break;
case bfd_mach_alpha_ev5:
isa_mask |= AXP_OPCODE_EV5;
break;
case bfd_mach_alpha_ev6:
isa_mask |= AXP_OPCODE_EV6;
break;
}
/* Read the insn into a host word */
{
bfd_byte buffer[4];
int status = (*info->read_memory_func) (memaddr, buffer, 4, info);
if (status != 0)
{
(*info->memory_error_func) (status, memaddr, info);
return -1;
}
insn = bfd_getl32 (buffer);
}
/* Get the major opcode of the instruction. */
op = AXP_OP (insn);
/* Find the first match in the opcode table. */
opcode_end = opcode_index[op + 1];
for (opcode = opcode_index[op]; opcode < opcode_end; ++opcode)
{
if ((insn ^ opcode->opcode) & opcode->mask)
continue;
if (!(opcode->flags & isa_mask))
continue;
/* 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. */
{
int invalid = 0;
for (opindex = opcode->operands; *opindex != 0; opindex++)
{
const struct alpha_operand *operand = alpha_operands + *opindex;
if (operand->extract)
(*operand->extract) (insn, &invalid);
}
if (invalid)
continue;
}
/* The instruction is valid. */
goto found;
}
/* No instruction found */
(*info->fprintf_func) (info->stream, ".long %#08x", insn);
return 4;
found:
(*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. */
need_comma = 0;
for (opindex = opcode->operands; *opindex != 0; opindex++)
{
const struct alpha_operand *operand = alpha_operands + *opindex;
int value;
/* Operands that are marked FAKE are simply ignored. We
already made sure that the extract function considered
the instruction to be valid. */
if ((operand->flags & AXP_OPERAND_FAKE) != 0)
continue;
/* Extract the value from the instruction. */
if (operand->extract)
value = (*operand->extract) (insn, (int *) NULL);
else
{
value = (insn >> operand->shift) & ((1 << operand->bits) - 1);
if (operand->flags & AXP_OPERAND_SIGNED)
{
int signbit = 1 << (operand->bits - 1);
value = (value ^ signbit) - signbit;
}
}
if (need_comma &&
((operand->flags & (AXP_OPERAND_PARENS | AXP_OPERAND_COMMA))
!= AXP_OPERAND_PARENS))
{
(*info->fprintf_func) (info->stream, ",");
}
if (operand->flags & AXP_OPERAND_PARENS)
(*info->fprintf_func) (info->stream, "(");
/* Print the operand as directed by the flags. */
if (operand->flags & AXP_OPERAND_IR)
(*info->fprintf_func) (info->stream, "%s", regnames[value]);
else if (operand->flags & AXP_OPERAND_FPR)
(*info->fprintf_func) (info->stream, "%s", regnames[value + 32]);
else if (operand->flags & AXP_OPERAND_RELATIVE)
(*info->print_address_func) (memaddr + 4 + value, info);
else if (operand->flags & AXP_OPERAND_SIGNED)
(*info->fprintf_func) (info->stream, "%d", value);
else
(*info->fprintf_func) (info->stream, "%#x", value);
if (operand->flags & AXP_OPERAND_PARENS)
(*info->fprintf_func) (info->stream, ")");
need_comma = 1;
}
return 4;
}