/* Print i386 instructions for GDB, the GNU debugger.
   Copyright (C) 1988, 1989, 1991, 1993, 1994, 1995 Free Software Foundation, Inc.

This file is part of GDB.

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.  */

/*
 * 80386 instruction printer by Pace Willisson (pace@prep.ai.mit.edu)
 * July 1988
 *  modified by John Hassey (hassey@dg-rtp.dg.com)
 */

/*
 * The main tables describing the instructions is essentially a copy
 * of the "Opcode Map" chapter (Appendix A) of the Intel 80386
 * Programmers Manual.  Usually, there is a capital letter, followed
 * by a small letter.  The capital letter tell the addressing mode,
 * and the small letter tells about the operand size.  Refer to 
 * the Intel manual for details.
 */

#include "dis-asm.h"
#include "sysdep.h"

#define MAXLEN 20

#include <setjmp.h>

struct dis_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 dis_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 dis_private *priv = (struct dis_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;
}

#define Eb OP_E, b_mode
#define indirEb OP_indirE, b_mode
#define Gb OP_G, b_mode
#define Ev OP_E, v_mode
#define indirEv OP_indirE, v_mode
#define Ew OP_E, w_mode
#define Ma OP_E, v_mode
#define M OP_E, 0
#define Mp OP_E, 0		/* ? */
#define Gv OP_G, v_mode
#define Gw OP_G, w_mode
#define Rw OP_rm, w_mode
#define Rd OP_rm, d_mode
#define Ib OP_I, b_mode
#define sIb OP_sI, b_mode	/* sign extened byte */
#define Iv OP_I, v_mode
#define Iw OP_I, w_mode
#define Jb OP_J, b_mode
#define Jv OP_J, v_mode
#define ONE OP_ONE, 0
#define Cd OP_C, d_mode
#define Dd OP_D, d_mode
#define Td OP_T, d_mode

#define eAX OP_REG, eAX_reg
#define eBX OP_REG, eBX_reg
#define eCX OP_REG, eCX_reg
#define eDX OP_REG, eDX_reg
#define eSP OP_REG, eSP_reg
#define eBP OP_REG, eBP_reg
#define eSI OP_REG, eSI_reg
#define eDI OP_REG, eDI_reg
#define AL OP_REG, al_reg
#define CL OP_REG, cl_reg
#define DL OP_REG, dl_reg
#define BL OP_REG, bl_reg
#define AH OP_REG, ah_reg
#define CH OP_REG, ch_reg
#define DH OP_REG, dh_reg
#define BH OP_REG, bh_reg
#define AX OP_REG, ax_reg
#define DX OP_REG, dx_reg
#define indirDX OP_REG, indir_dx_reg

#define Sw OP_SEG, w_mode
#define Ap OP_DIR, lptr
#define Av OP_DIR, v_mode
#define Ob OP_OFF, b_mode
#define Ov OP_OFF, v_mode
#define Xb OP_DSSI, b_mode
#define Xv OP_DSSI, v_mode
#define Yb OP_ESDI, b_mode
#define Yv OP_ESDI, v_mode

#define es OP_REG, es_reg
#define ss OP_REG, ss_reg
#define cs OP_REG, cs_reg
#define ds OP_REG, ds_reg
#define fs OP_REG, fs_reg
#define gs OP_REG, gs_reg

int OP_E(), OP_indirE(), OP_G(), OP_I(), OP_sI(), OP_REG();
int OP_J(), OP_SEG();
int OP_DIR(), OP_OFF(), OP_DSSI(), OP_ESDI(), OP_ONE(), OP_C();
int OP_D(), OP_T(), OP_rm();

static void dofloat (), putop (), append_prefix (), set_op ();
static int get16 (), get32 ();

#define b_mode 1
#define v_mode 2
#define w_mode 3
#define d_mode 4

#define es_reg 100
#define cs_reg 101
#define ss_reg 102
#define ds_reg 103
#define fs_reg 104
#define gs_reg 105
#define eAX_reg 107
#define eCX_reg 108
#define eDX_reg 109
#define eBX_reg 110
#define eSP_reg 111
#define eBP_reg 112
#define eSI_reg 113
#define eDI_reg 114

#define lptr 115

#define al_reg 116
#define cl_reg 117
#define dl_reg 118
#define bl_reg 119
#define ah_reg 120
#define ch_reg 121
#define dh_reg 122
#define bh_reg 123

#define ax_reg 124
#define cx_reg 125
#define dx_reg 126
#define bx_reg 127
#define sp_reg 128
#define bp_reg 129
#define si_reg 130
#define di_reg 131

#define indir_dx_reg 150

#define GRP1b NULL, NULL, 0
#define GRP1S NULL, NULL, 1
#define GRP1Ss NULL, NULL, 2
#define GRP2b NULL, NULL, 3
#define GRP2S NULL, NULL, 4
#define GRP2b_one NULL, NULL, 5
#define GRP2S_one NULL, NULL, 6
#define GRP2b_cl NULL, NULL, 7
#define GRP2S_cl NULL, NULL, 8
#define GRP3b NULL, NULL, 9
#define GRP3S NULL, NULL, 10
#define GRP4  NULL, NULL, 11
#define GRP5  NULL, NULL, 12
#define GRP6  NULL, NULL, 13
#define GRP7 NULL, NULL, 14
#define GRP8 NULL, NULL, 15
#define GRP9 NULL, NULL, 16

#define FLOATCODE 50
#define FLOAT NULL, NULL, FLOATCODE

struct dis386 {
  char *name;
  int (*op1)();
  int bytemode1;
  int (*op2)();
  int bytemode2;
  int (*op3)();
  int bytemode3;
};

struct dis386 dis386[] = {
  /* 00 */
  { "addb",	Eb, Gb },
  { "addS",	Ev, Gv },
  { "addb",	Gb, Eb },
  { "addS",	Gv, Ev },
  { "addb",	AL, Ib },
  { "addS",	eAX, Iv },
  { "pushl",	es },
  { "popl",	es },
  /* 08 */
  { "orb",	Eb, Gb },
  { "orS",	Ev, Gv },
  { "orb",	Gb, Eb },
  { "orS",	Gv, Ev },
  { "orb",	AL, Ib },
  { "orS",	eAX, Iv },
  { "pushl",	cs },
  { "(bad)" },	/* 0x0f extended opcode escape */
  /* 10 */
  { "adcb",	Eb, Gb },
  { "adcS",	Ev, Gv },
  { "adcb",	Gb, Eb },
  { "adcS",	Gv, Ev },
  { "adcb",	AL, Ib },
  { "adcS",	eAX, Iv },
  { "pushl",	ss },
  { "popl",	ss },
  /* 18 */
  { "sbbb",	Eb, Gb },
  { "sbbS",	Ev, Gv },
  { "sbbb",	Gb, Eb },
  { "sbbS",	Gv, Ev },
  { "sbbb",	AL, Ib },
  { "sbbS",	eAX, Iv },
  { "pushl",	ds },
  { "popl",	ds },
  /* 20 */
  { "andb",	Eb, Gb },
  { "andS",	Ev, Gv },
  { "andb",	Gb, Eb },
  { "andS",	Gv, Ev },
  { "andb",	AL, Ib },
  { "andS",	eAX, Iv },
  { "(bad)" },			/* SEG ES prefix */
  { "daa" },
  /* 28 */
  { "subb",	Eb, Gb },
  { "subS",	Ev, Gv },
  { "subb",	Gb, Eb },
  { "subS",	Gv, Ev },
  { "subb",	AL, Ib },
  { "subS",	eAX, Iv },
  { "(bad)" },			/* SEG CS prefix */
  { "das" },
  /* 30 */
  { "xorb",	Eb, Gb },
  { "xorS",	Ev, Gv },
  { "xorb",	Gb, Eb },
  { "xorS",	Gv, Ev },
  { "xorb",	AL, Ib },
  { "xorS",	eAX, Iv },
  { "(bad)" },			/* SEG SS prefix */
  { "aaa" },
  /* 38 */
  { "cmpb",	Eb, Gb },
  { "cmpS",	Ev, Gv },
  { "cmpb",	Gb, Eb },
  { "cmpS",	Gv, Ev },
  { "cmpb",	AL, Ib },
  { "cmpS",	eAX, Iv },
  { "(bad)" },			/* SEG DS prefix */
  { "aas" },
  /* 40 */
  { "incS",	eAX },
  { "incS",	eCX },
  { "incS",	eDX },
  { "incS",	eBX },
  { "incS",	eSP },
  { "incS",	eBP },
  { "incS",	eSI },
  { "incS",	eDI },
  /* 48 */
  { "decS",	eAX },
  { "decS",	eCX },
  { "decS",	eDX },
  { "decS",	eBX },
  { "decS",	eSP },
  { "decS",	eBP },
  { "decS",	eSI },
  { "decS",	eDI },
  /* 50 */
  { "pushS",	eAX },
  { "pushS",	eCX },
  { "pushS",	eDX },
  { "pushS",	eBX },
  { "pushS",	eSP },
  { "pushS",	eBP },
  { "pushS",	eSI },
  { "pushS",	eDI },
  /* 58 */
  { "popS",	eAX },
  { "popS",	eCX },
  { "popS",	eDX },
  { "popS",	eBX },
  { "popS",	eSP },
  { "popS",	eBP },
  { "popS",	eSI },
  { "popS",	eDI },
  /* 60 */
  { "pusha" },
  { "popa" },
  { "boundS",	Gv, Ma },
  { "arpl",	Ew, Gw },
  { "(bad)" },			/* seg fs */
  { "(bad)" },			/* seg gs */
  { "(bad)" },			/* op size prefix */
  { "(bad)" },			/* adr size prefix */
  /* 68 */
  { "pushS",	Iv },		/* 386 book wrong */
  { "imulS",	Gv, Ev, Iv },
  { "pushl",	sIb },		/* push of byte really pushes 4 bytes */
  { "imulS",	Gv, Ev, Ib },
  { "insb",	Yb, indirDX },
  { "insS",	Yv, indirDX },
  { "outsb",	indirDX, Xb },
  { "outsS",	indirDX, Xv },
  /* 70 */
  { "jo",		Jb },
  { "jno",	Jb },
  { "jb",		Jb },
  { "jae",	Jb },
  { "je",		Jb },
  { "jne",	Jb },
  { "jbe",	Jb },
  { "ja",		Jb },
  /* 78 */
  { "js",		Jb },
  { "jns",	Jb },
  { "jp",		Jb },
  { "jnp",	Jb },
  { "jl",		Jb },
  { "jnl",	Jb },
  { "jle",	Jb },
  { "jg",		Jb },
  /* 80 */
  { GRP1b },
  { GRP1S },
  { "(bad)" },
  { GRP1Ss },
  { "testb",	Eb, Gb },
  { "testS",	Ev, Gv },
  { "xchgb",	Eb, Gb },
  { "xchgS",	Ev, Gv },
  /* 88 */
  { "movb",	Eb, Gb },
  { "movS",	Ev, Gv },
  { "movb",	Gb, Eb },
  { "movS",	Gv, Ev },
  { "movw",	Ew, Sw },
  { "leaS",	Gv, M },
  { "movw",	Sw, Ew },
  { "popS",	Ev },
  /* 90 */
  { "nop" },
  { "xchgS",	eCX, eAX },
  { "xchgS",	eDX, eAX },
  { "xchgS",	eBX, eAX },
  { "xchgS",	eSP, eAX },
  { "xchgS",	eBP, eAX },
  { "xchgS",	eSI, eAX },
  { "xchgS",	eDI, eAX },
  /* 98 */
  { "cwtl" },
  { "cltd" },
  { "lcall",	Ap },
  { "(bad)" },		/* fwait */
  { "pushf" },
  { "popf" },
  { "sahf" },
  { "lahf" },
  /* a0 */
  { "movb",	AL, Ob },
  { "movS",	eAX, Ov },
  { "movb",	Ob, AL },
  { "movS",	Ov, eAX },
  { "movsb",	Yb, Xb },
  { "movsS",	Yv, Xv },
  { "cmpsb",	Yb, Xb },
  { "cmpsS",	Yv, Xv },
  /* a8 */
  { "testb",	AL, Ib },
  { "testS",	eAX, Iv },
  { "stosb",	Yb, AL },
  { "stosS",	Yv, eAX },
  { "lodsb",	AL, Xb },
  { "lodsS",	eAX, Xv },
  { "scasb",	AL, Yb },
  { "scasS",	eAX, Yv },
  /* b0 */
  { "movb",	AL, Ib },
  { "movb",	CL, Ib },
  { "movb",	DL, Ib },
  { "movb",	BL, Ib },
  { "movb",	AH, Ib },
  { "movb",	CH, Ib },
  { "movb",	DH, Ib },
  { "movb",	BH, Ib },
  /* b8 */
  { "movS",	eAX, Iv },
  { "movS",	eCX, Iv },
  { "movS",	eDX, Iv },
  { "movS",	eBX, Iv },
  { "movS",	eSP, Iv },
  { "movS",	eBP, Iv },
  { "movS",	eSI, Iv },
  { "movS",	eDI, Iv },
  /* c0 */
  { GRP2b },
  { GRP2S },
  { "ret",	Iw },
  { "ret" },
  { "lesS",	Gv, Mp },
  { "ldsS",	Gv, Mp },
  { "movb",	Eb, Ib },
  { "movS",	Ev, Iv },
  /* c8 */
  { "enter",	Iw, Ib },
  { "leave" },
  { "lret",	Iw },
  { "lret" },
  { "int3" },
  { "int",	Ib },
  { "into" },
  { "iret" },
  /* d0 */
  { GRP2b_one },
  { GRP2S_one },
  { GRP2b_cl },
  { GRP2S_cl },
  { "aam",	Ib },
  { "aad",	Ib },
  { "(bad)" },
  { "xlat" },
  /* d8 */
  { FLOAT },
  { FLOAT },
  { FLOAT },
  { FLOAT },
  { FLOAT },
  { FLOAT },
  { FLOAT },
  { FLOAT },
  /* e0 */
  { "loopne",	Jb },
  { "loope",	Jb },
  { "loop",	Jb },
  { "jCcxz",	Jb },
  { "inb",	AL, Ib },
  { "inS",	eAX, Ib },
  { "outb",	Ib, AL },
  { "outS",	Ib, eAX },
  /* e8 */
  { "call",	Av },
  { "jmp",	Jv },
  { "ljmp",	Ap },
  { "jmp",	Jb },
  { "inb",	AL, indirDX },
  { "inS",	eAX, indirDX },
  { "outb",	indirDX, AL },
  { "outS",	indirDX, eAX },
  /* f0 */
  { "(bad)" },			/* lock prefix */
  { "(bad)" },
  { "(bad)" },			/* repne */
  { "(bad)" },			/* repz */
  { "hlt" },
  { "cmc" },
  { GRP3b },
  { GRP3S },
  /* f8 */
  { "clc" },
  { "stc" },
  { "cli" },
  { "sti" },
  { "cld" },
  { "std" },
  { GRP4 },
  { GRP5 },
};

struct dis386 dis386_twobyte[] = {
  /* 00 */
  { GRP6 },
  { GRP7 },
  { "larS", Gv, Ew },
  { "lslS", Gv, Ew },  
  { "(bad)" },
  { "(bad)" },
  { "clts" },
  { "(bad)" },  
  /* 08 */
  { "invd" },
  { "wbinvd" },
  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* 10 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* 18 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* 20 */
  /* these are all backward in appendix A of the intel book */
  { "movl", Rd, Cd },
  { "movl", Rd, Dd },
  { "movl", Cd, Rd },
  { "movl", Dd, Rd },  
  { "movl", Rd, Td },
  { "(bad)" },
  { "movl", Td, Rd },
  { "(bad)" },  
  /* 28 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* 30 */
  { "wrmsr" },  { "rdtsc" },  { "rdmsr" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* 38 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* 40 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* 48 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* 50 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* 58 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* 60 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* 68 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* 70 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* 78 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* 80 */
  { "jo", Jv },
  { "jno", Jv },
  { "jb", Jv },
  { "jae", Jv },  
  { "je", Jv },
  { "jne", Jv },
  { "jbe", Jv },
  { "ja", Jv },  
  /* 88 */
  { "js", Jv },
  { "jns", Jv },
  { "jp", Jv },
  { "jnp", Jv },  
  { "jl", Jv },
  { "jge", Jv },
  { "jle", Jv },
  { "jg", Jv },  
  /* 90 */
  { "seto", Eb },
  { "setno", Eb },
  { "setb", Eb },
  { "setae", Eb },
  { "sete", Eb },
  { "setne", Eb },
  { "setbe", Eb },
  { "seta", Eb },
  /* 98 */
  { "sets", Eb },
  { "setns", Eb },
  { "setp", Eb },
  { "setnp", Eb },
  { "setl", Eb },
  { "setge", Eb },
  { "setle", Eb },
  { "setg", Eb },  
  /* a0 */
  { "pushl", fs },
  { "popl", fs },
  { "cpuid" },
  { "btS", Ev, Gv },  
  { "shldS", Ev, Gv, Ib },
  { "shldS", Ev, Gv, CL },
  { "(bad)" },
  { "(bad)" },  
  /* a8 */
  { "pushl", gs },
  { "popl", gs },
  { "rsm" },
  { "btsS", Ev, Gv },  
  { "shrdS", Ev, Gv, Ib },
  { "shrdS", Ev, Gv, CL },
  { "(bad)" },
  { "imulS", Gv, Ev },  
  /* b0 */
  { "cmpxchgb", Eb, Gb },
  { "cmpxchgS", Ev, Gv },
  { "lssS", Gv, Mp },	/* 386 lists only Mp */
  { "btrS", Ev, Gv },  
  { "lfsS", Gv, Mp },	/* 386 lists only Mp */
  { "lgsS", Gv, Mp },	/* 386 lists only Mp */
  { "movzbS", Gv, Eb },
  { "movzwS", Gv, Ew },  
  /* b8 */
  { "(bad)" },
  { "(bad)" },
  { GRP8 },
  { "btcS", Ev, Gv },  
  { "bsfS", Gv, Ev },
  { "bsrS", Gv, Ev },
  { "movsbS", Gv, Eb },
  { "movswS", Gv, Ew },  
  /* c0 */
  { "xaddb", Eb, Gb },
  { "xaddS", Ev, Gv },
  { "(bad)" },
  { "(bad)" },  
  { "(bad)" },
  { "(bad)" },
  { "(bad)" },
  { GRP9 },  
  /* c8 */
  { "bswap", eAX },
  { "bswap", eCX },
  { "bswap", eDX },
  { "bswap", eBX },
  { "bswap", eSP },
  { "bswap", eBP },
  { "bswap", eSI },
  { "bswap", eDI },
  /* d0 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* d8 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* e0 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* e8 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* f0 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  /* f8 */
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
  { "(bad)" },  { "(bad)" },  { "(bad)" },  { "(bad)" },  
};

static char obuf[100];
static char *obufp;
static char scratchbuf[100];
static unsigned char *start_codep;
static unsigned char *codep;
static disassemble_info *the_info;
static int mod;
static int rm;
static int reg;
static void oappend ();

static char *names32[]={
  "%eax","%ecx","%edx","%ebx", "%esp","%ebp","%esi","%edi",
};
static char *names16[] = {
  "%ax","%cx","%dx","%bx","%sp","%bp","%si","%di",
};
static char *names8[] = {
  "%al","%cl","%dl","%bl","%ah","%ch","%dh","%bh",
};
static char *names_seg[] = {
  "%es","%cs","%ss","%ds","%fs","%gs","%?","%?",
};

struct dis386 grps[][8] = {
  /* GRP1b */
  {
    { "addb",	Eb, Ib },
    { "orb",	Eb, Ib },
    { "adcb",	Eb, Ib },
    { "sbbb",	Eb, Ib },
    { "andb",	Eb, Ib },
    { "subb",	Eb, Ib },
    { "xorb",	Eb, Ib },
    { "cmpb",	Eb, Ib }
  },
  /* GRP1S */
  {
    { "addS",	Ev, Iv },
    { "orS",	Ev, Iv },
    { "adcS",	Ev, Iv },
    { "sbbS",	Ev, Iv },
    { "andS",	Ev, Iv },
    { "subS",	Ev, Iv },
    { "xorS",	Ev, Iv },
    { "cmpS",	Ev, Iv }
  },
  /* GRP1Ss */
  {
    { "addS",	Ev, sIb },
    { "orS",	Ev, sIb },
    { "adcS",	Ev, sIb },
    { "sbbS",	Ev, sIb },
    { "andS",	Ev, sIb },
    { "subS",	Ev, sIb },
    { "xorS",	Ev, sIb },
    { "cmpS",	Ev, sIb }
  },
  /* GRP2b */
  {
    { "rolb",	Eb, Ib },
    { "rorb",	Eb, Ib },
    { "rclb",	Eb, Ib },
    { "rcrb",	Eb, Ib },
    { "shlb",	Eb, Ib },
    { "shrb",	Eb, Ib },
    { "(bad)" },
    { "sarb",	Eb, Ib },
  },
  /* GRP2S */
  {
    { "rolS",	Ev, Ib },
    { "rorS",	Ev, Ib },
    { "rclS",	Ev, Ib },
    { "rcrS",	Ev, Ib },
    { "shlS",	Ev, Ib },
    { "shrS",	Ev, Ib },
    { "(bad)" },
    { "sarS",	Ev, Ib },
  },
  /* GRP2b_one */
  {
    { "rolb",	Eb },
    { "rorb",	Eb },
    { "rclb",	Eb },
    { "rcrb",	Eb },
    { "shlb",	Eb },
    { "shrb",	Eb },
    { "(bad)" },
    { "sarb",	Eb },
  },
  /* GRP2S_one */
  {
    { "rolS",	Ev },
    { "rorS",	Ev },
    { "rclS",	Ev },
    { "rcrS",	Ev },
    { "shlS",	Ev },
    { "shrS",	Ev },
    { "(bad)" },
    { "sarS",	Ev },
  },
  /* GRP2b_cl */
  {
    { "rolb",	Eb, CL },
    { "rorb",	Eb, CL },
    { "rclb",	Eb, CL },
    { "rcrb",	Eb, CL },
    { "shlb",	Eb, CL },
    { "shrb",	Eb, CL },
    { "(bad)" },
    { "sarb",	Eb, CL },
  },
  /* GRP2S_cl */
  {
    { "rolS",	Ev, CL },
    { "rorS",	Ev, CL },
    { "rclS",	Ev, CL },
    { "rcrS",	Ev, CL },
    { "shlS",	Ev, CL },
    { "shrS",	Ev, CL },
    { "(bad)" },
    { "sarS",	Ev, CL }
  },
  /* GRP3b */
  {
    { "testb",	Eb, Ib },
    { "(bad)",	Eb },
    { "notb",	Eb },
    { "negb",	Eb },
    { "mulb",	AL, Eb },
    { "imulb",	AL, Eb },
    { "divb",	AL, Eb },
    { "idivb",	AL, Eb }
  },
  /* GRP3S */
  {
    { "testS",	Ev, Iv },
    { "(bad)" },
    { "notS",	Ev },
    { "negS",	Ev },
    { "mulS",	eAX, Ev },
    { "imulS",	eAX, Ev },
    { "divS",	eAX, Ev },
    { "idivS",	eAX, Ev },
  },
  /* GRP4 */
  {
    { "incb", Eb },
    { "decb", Eb },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
  },
  /* GRP5 */
  {
    { "incS",	Ev },
    { "decS",	Ev },
    { "call",	indirEv },
    { "lcall",	indirEv },
    { "jmp",	indirEv },
    { "ljmp",	indirEv },
    { "pushS",	Ev },
    { "(bad)" },
  },
  /* GRP6 */
  {
    { "sldt",	Ew },
    { "str",	Ew },
    { "lldt",	Ew },
    { "ltr",	Ew },
    { "verr",	Ew },
    { "verw",	Ew },
    { "(bad)" },
    { "(bad)" }
  },
  /* GRP7 */
  {
    { "sgdt", Ew },
    { "sidt", Ew },
    { "lgdt", Ew },
    { "lidt", Ew },
    { "smsw", Ew },
    { "(bad)" },
    { "lmsw", Ew },
    { "invlpg", Ew },
  },
  /* GRP8 */
  {
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { "btS",	Ev, Ib },
    { "btsS",	Ev, Ib },
    { "btrS",	Ev, Ib },
    { "btcS",	Ev, Ib },
  },
  /* GRP9 */
  {
    { "(bad)" },
    { "cmpxchg8b", Ev },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
  }
};

#define PREFIX_REPZ 1
#define PREFIX_REPNZ 2
#define PREFIX_LOCK 4
#define PREFIX_CS 8
#define PREFIX_SS 0x10
#define PREFIX_DS 0x20
#define PREFIX_ES 0x40
#define PREFIX_FS 0x80
#define PREFIX_GS 0x100
#define PREFIX_DATA 0x200
#define PREFIX_ADR 0x400
#define PREFIX_FWAIT 0x800

static int prefixes;

static void
ckprefix ()
{
  prefixes = 0;
  while (1)
    {
      FETCH_DATA (the_info, codep + 1);
      switch (*codep)
	{
	case 0xf3:
	  prefixes |= PREFIX_REPZ;
	  break;
	case 0xf2:
	  prefixes |= PREFIX_REPNZ;
	  break;
	case 0xf0:
	  prefixes |= PREFIX_LOCK;
	  break;
	case 0x2e:
	  prefixes |= PREFIX_CS;
	  break;
	case 0x36:
	  prefixes |= PREFIX_SS;
	  break;
	case 0x3e:
	  prefixes |= PREFIX_DS;
	  break;
	case 0x26:
	  prefixes |= PREFIX_ES;
	  break;
	case 0x64:
	  prefixes |= PREFIX_FS;
	  break;
	case 0x65:
	  prefixes |= PREFIX_GS;
	  break;
	case 0x66:
	  prefixes |= PREFIX_DATA;
	  break;
	case 0x67:
	  prefixes |= PREFIX_ADR;
	  break;
	case 0x9b:
	  prefixes |= PREFIX_FWAIT;
	  break;
	default:
	  return;
	}
      codep++;
    }
}

static int dflag;
static int aflag;		

static char op1out[100], op2out[100], op3out[100];
static int op_address[3], op_ad, op_index[3];
static int start_pc;


/*
 *   On the 386's of 1988, the maximum length of an instruction is 15 bytes.
 *   (see topic "Redundant prefixes" in the "Differences from 8086"
 *   section of the "Virtual 8086 Mode" chapter.)
 * 'pc' should be the address of this instruction, it will
 *   be used to print the target address if this is a relative jump or call
 * The function returns the length of this instruction in bytes.
 */

int
print_insn_i386 (pc, info)
     bfd_vma pc;
     disassemble_info *info;
{
  struct dis386 *dp;
  int i;
  int enter_instruction;
  char *first, *second, *third;
  int needcomma;
  
  struct dis_private priv;
  bfd_byte *inbuf = priv.the_buffer;

  info->private_data = (PTR) &priv;
  priv.max_fetched = priv.the_buffer;
  priv.insn_start = pc;
  if (setjmp (priv.bailout) != 0)
    /* Error return.  */
    return -1;

  obuf[0] = 0;
  op1out[0] = 0;
  op2out[0] = 0;
  op3out[0] = 0;

  op_index[0] = op_index[1] = op_index[2] = -1;

  the_info = info;
  start_pc = pc;
  start_codep = inbuf;
  codep = inbuf;
  
  ckprefix ();

  FETCH_DATA (info, codep + 1);
  if (*codep == 0xc8)
    enter_instruction = 1;
  else
    enter_instruction = 0;
  
  obufp = obuf;
  
  if (prefixes & PREFIX_REPZ)
    oappend ("repz ");
  if (prefixes & PREFIX_REPNZ)
    oappend ("repnz ");
  if (prefixes & PREFIX_LOCK)
    oappend ("lock ");
  
  if ((prefixes & PREFIX_FWAIT)
      && ((*codep < 0xd8) || (*codep > 0xdf)))
    {
      /* fwait not followed by floating point instruction */
      (*info->fprintf_func) (info->stream, "fwait");
      return (1);
    }
  
  /* these would be initialized to 0 if disassembling for 8086 or 286 */
  dflag = 1;
  aflag = 1;
  
  if (prefixes & PREFIX_DATA)
    dflag ^= 1;
  
  if (prefixes & PREFIX_ADR)
    {
      aflag ^= 1;
      oappend ("addr16 ");
    }
  
  if (*codep == 0x0f)
    {
      FETCH_DATA (info, codep + 2);
      dp = &dis386_twobyte[*++codep];
    }
  else
    dp = &dis386[*codep];
  codep++;

  /* Fetch the mod/reg/rm byte.  FIXME: We should be only fetching
     this if we need it.  As it is, this code loses if there is a
     one-byte instruction (without a mod/reg/rm byte) at the end of
     the address space.  */

  FETCH_DATA (info, codep + 1);
  mod = (*codep >> 6) & 3;
  reg = (*codep >> 3) & 7;
  rm = *codep & 7;

  if (dp->name == NULL && dp->bytemode1 == FLOATCODE)
    {
      dofloat ();
    }
  else
    {
      if (dp->name == NULL)
	dp = &grps[dp->bytemode1][reg];
      
      putop (dp->name);
      
      obufp = op1out;
      op_ad = 2;
      if (dp->op1)
	(*dp->op1)(dp->bytemode1);
      
      obufp = op2out;
      op_ad = 1;
      if (dp->op2)
	(*dp->op2)(dp->bytemode2);
      
      obufp = op3out;
      op_ad = 0;
      if (dp->op3)
	(*dp->op3)(dp->bytemode3);
    }
  
  obufp = obuf + strlen (obuf);
  for (i = strlen (obuf); i < 6; i++)
    oappend (" ");
  oappend (" ");
  (*info->fprintf_func) (info->stream, "%s", obuf);
  
  /* enter instruction is printed with operands in the
   * same order as the intel book; everything else
   * is printed in reverse order 
   */
  if (enter_instruction)
    {
      first = op1out;
      second = op2out;
      third = op3out;
      op_ad = op_index[0];
      op_index[0] = op_index[2];
      op_index[2] = op_ad;
    }
  else
    {
      first = op3out;
      second = op2out;
      third = op1out;
    }
  needcomma = 0;
  if (*first)
    {
      if (op_index[0] != -1)
	(*info->print_address_func) (op_address[op_index[0]], info);
      else
	(*info->fprintf_func) (info->stream, "%s", first);
      needcomma = 1;
    }
  if (*second)
    {
      if (needcomma)
	(*info->fprintf_func) (info->stream, ",");
      if (op_index[1] != -1)
	(*info->print_address_func) (op_address[op_index[1]], info);
      else
	(*info->fprintf_func) (info->stream, "%s", second);
      needcomma = 1;
    }
  if (*third)
    {
      if (needcomma)
	(*info->fprintf_func) (info->stream, ",");
      if (op_index[2] != -1)
	(*info->print_address_func) (op_address[op_index[2]], info);
      else
	(*info->fprintf_func) (info->stream, "%s", third);
    }
  return (codep - inbuf);
}

char *float_mem[] = {
  /* d8 */
  "fadds",
  "fmuls",
  "fcoms",
  "fcomps",
  "fsubs",
  "fsubrs",
  "fdivs",
  "fdivrs",
  /*  d9 */
  "flds",
  "(bad)",
  "fsts",
  "fstps",
  "fldenv",
  "fldcw",
  "fNstenv",
  "fNstcw",
  /* da */
  "fiaddl",
  "fimull",
  "ficoml",
  "ficompl",
  "fisubl",
  "fisubrl",
  "fidivl",
  "fidivrl",
  /* db */
  "fildl",
  "(bad)",
  "fistl",
  "fistpl",
  "(bad)",
  "fldt",
  "(bad)",
  "fstpt",
  /* dc */
  "faddl",
  "fmull",
  "fcoml",
  "fcompl",
  "fsubl",
  "fsubrl",
  "fdivl",
  "fdivrl",
  /* dd */
  "fldl",
  "(bad)",
  "fstl",
  "fstpl",
  "frstor",
  "(bad)",
  "fNsave",
  "fNstsw",
  /* de */
  "fiadd",
  "fimul",
  "ficom",
  "ficomp",
  "fisub",
  "fisubr",
  "fidiv",
  "fidivr",
  /* df */
  "fild",
  "(bad)",
  "fist",
  "fistp",
  "fbld",
  "fildll",
  "fbstp",
  "fistpll",
};

#define ST OP_ST, 0
#define STi OP_STi, 0
int OP_ST(), OP_STi();

#define FGRPd9_2 NULL, NULL, 0
#define FGRPd9_4 NULL, NULL, 1
#define FGRPd9_5 NULL, NULL, 2
#define FGRPd9_6 NULL, NULL, 3
#define FGRPd9_7 NULL, NULL, 4
#define FGRPda_5 NULL, NULL, 5
#define FGRPdb_4 NULL, NULL, 6
#define FGRPde_3 NULL, NULL, 7
#define FGRPdf_4 NULL, NULL, 8

struct dis386 float_reg[][8] = {
  /* d8 */
  {
    { "fadd",	ST, STi },
    { "fmul",	ST, STi },
    { "fcom",	STi },
    { "fcomp",	STi },
    { "fsub",	ST, STi },
    { "fsubr",	ST, STi },
    { "fdiv",	ST, STi },
    { "fdivr",	ST, STi },
  },
  /* d9 */
  {
    { "fld",	STi },
    { "fxch",	STi },
    { FGRPd9_2 },
    { "(bad)" },
    { FGRPd9_4 },
    { FGRPd9_5 },
    { FGRPd9_6 },
    { FGRPd9_7 },
  },
  /* da */
  {
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { FGRPda_5 },
    { "(bad)" },
    { "(bad)" },
  },
  /* db */
  {
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { FGRPdb_4 },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
  },
  /* dc */
  {
    { "fadd",	STi, ST },
    { "fmul",	STi, ST },
    { "(bad)" },
    { "(bad)" },
    { "fsub",	STi, ST },
    { "fsubr",	STi, ST },
    { "fdiv",	STi, ST },
    { "fdivr",	STi, ST },
  },
  /* dd */
  {
    { "ffree",	STi },
    { "(bad)" },
    { "fst",	STi },
    { "fstp",	STi },
    { "fucom",	STi },
    { "fucomp",	STi },
    { "(bad)" },
    { "(bad)" },
  },
  /* de */
  {
    { "faddp",	STi, ST },
    { "fmulp",	STi, ST },
    { "(bad)" },
    { FGRPde_3 },
    { "fsubp",	STi, ST },
    { "fsubrp",	STi, ST },
    { "fdivp",	STi, ST },
    { "fdivrp",	STi, ST },
  },
  /* df */
  {
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
    { FGRPdf_4 },
    { "(bad)" },
    { "(bad)" },
    { "(bad)" },
  },
};


char *fgrps[][8] = {
  /* d9_2  0 */
  {
    "fnop","(bad)","(bad)","(bad)","(bad)","(bad)","(bad)","(bad)",
  },

  /* d9_4  1 */
  {
    "fchs","fabs","(bad)","(bad)","ftst","fxam","(bad)","(bad)",
  },

  /* d9_5  2 */
  {
    "fld1","fldl2t","fldl2e","fldpi","fldlg2","fldln2","fldz","(bad)",
  },

  /* d9_6  3 */
  {
    "f2xm1","fyl2x","fptan","fpatan","fxtract","fprem1","fdecstp","fincstp",
  },

  /* d9_7  4 */
  {
    "fprem","fyl2xp1","fsqrt","fsincos","frndint","fscale","fsin","fcos",
  },

  /* da_5  5 */
  {
    "(bad)","fucompp","(bad)","(bad)","(bad)","(bad)","(bad)","(bad)",
  },

  /* db_4  6 */
  {
    "feni(287 only)","fdisi(287 only)","fNclex","fNinit",
    "fNsetpm(287 only)","(bad)","(bad)","(bad)",
  },

  /* de_3  7 */
  {
    "(bad)","fcompp","(bad)","(bad)","(bad)","(bad)","(bad)","(bad)",
  },

  /* df_4  8 */
  {
    "fNstsw","(bad)","(bad)","(bad)","(bad)","(bad)","(bad)","(bad)",
  },
};

static void
dofloat ()
{
  struct dis386 *dp;
  unsigned char floatop;
  
  floatop = codep[-1];
  
  if (mod != 3)
    {
      putop (float_mem[(floatop - 0xd8) * 8 + reg]);
      obufp = op1out;
      OP_E (v_mode);
      return;
    }
  codep++;
  
  dp = &float_reg[floatop - 0xd8][reg];
  if (dp->name == NULL)
    {
      putop (fgrps[dp->bytemode1][rm]);
      /* instruction fnstsw is only one with strange arg */
      if (floatop == 0xdf
	  && FETCH_DATA (the_info, codep + 1)
	  && *codep == 0xe0)
	strcpy (op1out, "%eax");
    }
  else
    {
      putop (dp->name);
      obufp = op1out;
      if (dp->op1)
	(*dp->op1)(dp->bytemode1);
      obufp = op2out;
      if (dp->op2)
	(*dp->op2)(dp->bytemode2);
    }
}

/* ARGSUSED */
int
OP_ST (ignore)
     int ignore;
{
  oappend ("%st");
  return (0);
}

/* ARGSUSED */
int
OP_STi (ignore)
     int ignore;
{
  sprintf (scratchbuf, "%%st(%d)", rm);
  oappend (scratchbuf);
  return (0);
}


/* capital letters in template are macros */
static void
putop (template)
     char *template;
{
  char *p;
  
  for (p = template; *p; p++)
    {
      switch (*p)
	{
	default:
	  *obufp++ = *p;
	  break;
	case 'C':		/* For jcxz/jecxz */
	  if (aflag == 0)
	    *obufp++ = 'e';
	  break;
	case 'N':
	  if ((prefixes & PREFIX_FWAIT) == 0)
	    *obufp++ = 'n';
	  break;
	case 'S':
	  /* operand size flag */
	  if (dflag)
	    *obufp++ = 'l';
	  else
	    *obufp++ = 'w';
	  break;
	}
    }
  *obufp = 0;
}

static void
oappend (s)
     char *s;
{
  strcpy (obufp, s);
  obufp += strlen (s);
  *obufp = 0;
}

static void
append_prefix ()
{
  if (prefixes & PREFIX_CS)
    oappend ("%cs:");
  if (prefixes & PREFIX_DS)
    oappend ("%ds:");
  if (prefixes & PREFIX_SS)
    oappend ("%ss:");
  if (prefixes & PREFIX_ES)
    oappend ("%es:");
  if (prefixes & PREFIX_FS)
    oappend ("%fs:");
  if (prefixes & PREFIX_GS)
    oappend ("%gs:");
}

int
OP_indirE (bytemode)
     int bytemode;
{
  oappend ("*");
  OP_E (bytemode);
  return (0);
}

int
OP_E (bytemode)
     int bytemode;
{
  int disp;
  int havesib;
  int base;
  int index;
  int scale;
  int havebase;
  
  /* skip mod/rm byte */
  codep++;
  
  havesib = 0;
  havebase = 0;
  disp = 0;
  
  if (mod == 3)
    {
      switch (bytemode)
	{
	case b_mode:
	  oappend (names8[rm]);
	  break;
	case w_mode:
	  oappend (names16[rm]);
	  break;
	case v_mode:
	  if (dflag)
	    oappend (names32[rm]);
	  else
	    oappend (names16[rm]);
	  break;
	default:
	  oappend ("<bad dis table>");
	  break;
	}
      return (0);
    }
  
  append_prefix ();
  if (rm == 4)
    {
      havesib = 1;
      havebase = 1;
      FETCH_DATA (the_info, codep + 1);
      scale = (*codep >> 6) & 3;
      index = (*codep >> 3) & 7;
      base = *codep & 7;
      codep++;
    }
  
  switch (mod)
    {
    case 0:
      switch (rm)
	{
	case 4:
	  /* implies havesib and havebase */
	  if (base == 5) {
	    havebase = 0;
	    disp = get32 ();
	  }
	  break;
	case 5:
	  disp = get32 ();
	  break;
	default:
	  havebase = 1;
	  base = rm;
	  break;
	}
      break;
    case 1:
      FETCH_DATA (the_info, codep + 1);
      disp = *(char *)codep++;
      if (rm != 4)
	{
	  havebase = 1;
	  base = rm;
	}
      break;
    case 2:
      disp = get32 ();
      if (rm != 4)
	{
	  havebase = 1;
	  base = rm;
	}
      break;
    }
  
  if (mod != 0 || rm == 5 || (havesib && base == 5))
    {
      sprintf (scratchbuf, "0x%x", disp);
      oappend (scratchbuf);
    }
  
  if (havebase || havesib) 
    {
      oappend ("(");
      if (havebase)
	oappend (names32[base]);
      if (havesib) 
	{
	  if (index != 4) 
	    {
	      sprintf (scratchbuf, ",%s", names32[index]);
	      oappend (scratchbuf);
	    }
	  sprintf (scratchbuf, ",%d", 1 << scale);
	  oappend (scratchbuf);
	}
      oappend (")");
    }
  return (0);
}

int
OP_G (bytemode)
     int bytemode;
{
  switch (bytemode) 
    {
    case b_mode:
      oappend (names8[reg]);
      break;
    case w_mode:
      oappend (names16[reg]);
      break;
    case d_mode:
      oappend (names32[reg]);
      break;
    case v_mode:
      if (dflag)
	oappend (names32[reg]);
      else
	oappend (names16[reg]);
      break;
    default:
      oappend ("<internal disassembler error>");
      break;
    }
  return (0);
}

static int
get32 ()
{
  int x = 0;

  FETCH_DATA (the_info, codep + 4);
  x = *codep++ & 0xff;
  x |= (*codep++ & 0xff) << 8;
  x |= (*codep++ & 0xff) << 16;
  x |= (*codep++ & 0xff) << 24;
  return (x);
}

static int
get16 ()
{
  int x = 0;

  FETCH_DATA (the_info, codep + 2);
  x = *codep++ & 0xff;
  x |= (*codep++ & 0xff) << 8;
  return (x);
}

static void
set_op (op)
     int op;
{
  op_index[op_ad] = op_ad;
  op_address[op_ad] = op;
}

int
OP_REG (code)
     int code;
{
  char *s;
  
  switch (code) 
    {
    case indir_dx_reg: s = "(%dx)"; break;
	case ax_reg: case cx_reg: case dx_reg: case bx_reg:
	case sp_reg: case bp_reg: case si_reg: case di_reg:
		s = names16[code - ax_reg];
		break;
	case es_reg: case ss_reg: case cs_reg:
	case ds_reg: case fs_reg: case gs_reg:
		s = names_seg[code - es_reg];
		break;
	case al_reg: case ah_reg: case cl_reg: case ch_reg:
	case dl_reg: case dh_reg: case bl_reg: case bh_reg:
		s = names8[code - al_reg];
		break;
	case eAX_reg: case eCX_reg: case eDX_reg: case eBX_reg:
	case eSP_reg: case eBP_reg: case eSI_reg: case eDI_reg:
      if (dflag)
	s = names32[code - eAX_reg];
      else
	s = names16[code - eAX_reg];
      break;
    default:
      s = "<internal disassembler error>";
      break;
    }
  oappend (s);
  return (0);
}

int
OP_I (bytemode)
     int bytemode;
{
  int op;
  
  switch (bytemode) 
    {
    case b_mode:
      FETCH_DATA (the_info, codep + 1);
      op = *codep++ & 0xff;
      break;
    case v_mode:
      if (dflag)
	op = get32 ();
      else
	op = get16 ();
      break;
    case w_mode:
      op = get16 ();
      break;
    default:
      oappend ("<internal disassembler error>");
      return (0);
    }
  sprintf (scratchbuf, "$0x%x", op);
  oappend (scratchbuf);
  return (0);
}

int
OP_sI (bytemode)
     int bytemode;
{
  int op;
  
  switch (bytemode) 
    {
    case b_mode:
      FETCH_DATA (the_info, codep + 1);
      op = *(char *)codep++;
      break;
    case v_mode:
      if (dflag)
	op = get32 ();
      else
	op = (short)get16();
      break;
    case w_mode:
      op = (short)get16 ();
      break;
    default:
      oappend ("<internal disassembler error>");
      return (0);
    }
  sprintf (scratchbuf, "$0x%x", op);
  oappend (scratchbuf);
  return (0);
}

int
OP_J (bytemode)
     int bytemode;
{
  int disp;
  int mask = -1;
  
  switch (bytemode) 
    {
    case b_mode:
      FETCH_DATA (the_info, codep + 1);
      disp = *(char *)codep++;
      break;
    case v_mode:
      if (dflag)
	disp = get32 ();
      else
	{
	  disp = (short)get16 ();
	  /* for some reason, a data16 prefix on a jump instruction
	     means that the pc is masked to 16 bits after the
	     displacement is added!  */
	  mask = 0xffff;
	}
      break;
    default:
      oappend ("<internal disassembler error>");
      return (0);
    }
  disp = (start_pc + codep - start_codep + disp) & mask;
  set_op (disp);
  sprintf (scratchbuf, "0x%x", disp);
  oappend (scratchbuf);
  return (0);
}

/* ARGSUSED */
int
OP_SEG (dummy)
     int dummy;
{
  static char *sreg[] = {
    "%es","%cs","%ss","%ds","%fs","%gs","%?","%?",
  };

  oappend (sreg[reg]);
  return (0);
}

int
OP_DIR (size)
     int size;
{
  int seg, offset;
  
  switch (size) 
    {
    case lptr:
      if (aflag) 
	{
	  offset = get32 ();
	  seg = get16 ();
	} 
      else 
	{
	  offset = get16 ();
	  seg = get16 ();
	}
      sprintf (scratchbuf, "0x%x,0x%x", seg, offset);
      oappend (scratchbuf);
      break;
    case v_mode:
      if (aflag)
	offset = get32 ();
      else
	offset = (short)get16 ();
      
      offset = start_pc + codep - start_codep + offset;
      set_op (offset);
      sprintf (scratchbuf, "0x%x", offset);
      oappend (scratchbuf);
      break;
    default:
      oappend ("<internal disassembler error>");
      break;
    }
  return (0);
}

/* ARGSUSED */
int
OP_OFF (bytemode)
     int bytemode;
{
  int off;
  
  if (aflag)
    off = get32 ();
  else
    off = get16 ();
  
  sprintf (scratchbuf, "0x%x", off);
  oappend (scratchbuf);
  return (0);
}

/* ARGSUSED */
int
OP_ESDI (dummy)
    int dummy;
{
  oappend ("%es:(");
  oappend (aflag ? "%edi" : "%di");
  oappend (")");
  return (0);
}

/* ARGSUSED */
int
OP_DSSI (dummy)
    int dummy;
{
  oappend ("%ds:(");
  oappend (aflag ? "%esi" : "%si");
  oappend (")");
  return (0);
}

/* ARGSUSED */
int
OP_ONE (dummy)
    int dummy;
{
  oappend ("1");
  return (0);
}

/* ARGSUSED */
int
OP_C (dummy)
    int dummy;
{
  codep++; /* skip mod/rm */
  sprintf (scratchbuf, "%%cr%d", reg);
  oappend (scratchbuf);
  return (0);
}

/* ARGSUSED */
int
OP_D (dummy)
    int dummy;
{
  codep++; /* skip mod/rm */
  sprintf (scratchbuf, "%%db%d", reg);
  oappend (scratchbuf);
  return (0);
}

/* ARGSUSED */
int
OP_T (dummy)
     int dummy;
{
  codep++; /* skip mod/rm */
  sprintf (scratchbuf, "%%tr%d", reg);
  oappend (scratchbuf);
  return (0);
}

int
OP_rm (bytemode)
     int bytemode;
{
  switch (bytemode) 
    {
    case d_mode:
      oappend (names32[rm]);
      break;
    case w_mode:
      oappend (names16[rm]);
      break;
    }
  return (0);
}