/*
 * Copyright (c) 1999, 2000, 2002 Seth Kingsley.  All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgment:
 *    This product includes software developed by Seth Kingsley and
 *    contributors.
 * 4. Neither the author's name, nor any of the contributors names may be
 *    used to endorse or promote products derived from this software without
 *    specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include    <sys/param.h>

#include    <stdio.h>
#include    <sysexits.h>

#ifndef lint
static const char   rcsid[] =
	"$Id$";
#endif /* !lint */

#define EXT(n)	((n & 0x8000) ? (n | 0xffff0000) : n)

int
main(int ac, char *av[])
{
    struct
    {
	const char  *o_name;
	enum
	{
	    UKWN, JMP, STA, SA, BRCH, TSX, TSIM, TIM, TMEM, RTYP,
	    NONE, BRAK, S, SD, D, ST, DST, DTSH, DTS, CO
	}	    o_fmt;
    }	    ops[] =
    {
	{NULL, RTYP}, {NULL, BRCH}, {"j", JMP}, {"jal", JMP},
	{"beq", STA}, {"bne", STA}, {"blez", SA}, {"bgtz", SA},
	{"addi", TSX}, {"addiu", TSX}, {"slti", TSX}, {"sltiu", TSX},
	{"andi", TSIM}, {"ori", TSIM}, {"xori", TSIM}, {"lui", TIM},
	{"cop0", CO}, {"cop1", CO}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{"lb", TMEM}, {NULL, UKWN}, {NULL, UKWN}, {"lw", TMEM},
	{"lbu", TMEM}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{"sb", TMEM}, {NULL, UKWN}, {NULL, UKWN}, {"sw", TMEM},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {"lwc1", TMEM}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {"swc1", TMEM}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}
    },
	    fns[] =
    {
	{"sll", DTSH}, {NULL, UKWN}, {"srl", DTSH}, {"sra", DTSH},
	{"sllv", DTS}, {NULL, UKWN}, {"srlv", DTS}, {"srav", DTS},
	{"jr", S}, {"jalr", SD}, {NULL, UKWN}, {NULL, UKWN},
	{"syscall", NONE}, {"break", BRAK}, {NULL, UKWN}, {NULL, UKWN},
	{"mfhi", D}, {"mthi", S}, {"mflo", D}, {"mtlo", S},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{"mult", ST}, {"multu", ST}, {"div", ST}, {"divu", ST},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{"add", DST}, {"addu", DST}, {"sub", DST}, {"subu", DST},
	{"and", DST}, {"or", DST}, {"xor", DST}, {"nor", DST},
	{NULL, UKWN}, {NULL, UKWN}, {"slt", DST}, {"sltu", DST},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
    },
	    tops[] =
    {
	{"bltz", SA}, {"bgez", SA}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {"bltzal", SA},
	{"bgezal", SA}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN},
	{NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}, {NULL, UKWN}
    },
	    o;
    u_int   pc = 0x400000;	/* from SPIM */
    union
    {
	u_int	u_uint;
	struct
	{
	    u_int   r_func : 6,
		    r_shift : 5,
		    r_rd : 5, r_rt : 5, r_rs : 5,
		    r_op : 6;
	}	u_r;
#define	r_func	u_r.r_func
#define r_shift	u_r.r_shift
#define r_rd	u_r.r_rd
#define r_rt	u_r.r_rt
#define r_rs	u_r.r_rs
#define r_op	u_r.r_op
	struct
	{
	    u_int   i_imm : 16,
		    i_rt : 5, i_rs : 5,
		    i_op : 6;
	}	u_i;
#define i_imm	u_i.i_imm
#define i_rt	u_i.i_rt
#define i_rs	u_i.i_rs
#define i_op	u_i.i_op
	struct
	{
	    u_int   j_jmp : 26,
		    j_op : 6;
	}	u_j;
#define j_jmp	u_j.j_jmp
#define j_op	u_j.j_op
    }	    i;

    puts("   PC     HEX INST\t  TAL instruction\n");
    while (fread(&i, 4, 1, stdin))
    {
	i.u_uint = ntohl(i.u_uint);
	printf("%08x  %08x\t", pc, i.u_uint);
	pc+= 4;
	if (ops[i.r_op].o_fmt == RTYP)
	    o = fns[i.r_func];
	else if (ops[i.r_op].o_fmt == BRCH)
	    o = tops[i.r_rt];
	else
	    o = ops[i.r_op];
	if (o.o_name)
	    printf((o.o_fmt != NONE) ? "%s\t" : "%s\n", o.o_name);
	switch (o.o_fmt)
	{
	    case JMP:
		printf("%#.8x\n", i.j_jmp << 2);
		break;
	    case STA:
		printf("$%d, $%d, %#.8x\n",
			i.i_rs, i.i_rt, pc + (EXT(i.i_imm) << 2));
		break;
	    case SA:
		printf("$%d, %#.8x\n",
			i.i_rs, pc + (EXT(i.i_imm) << 2));
		break;
	    case TSX:
		printf("$%d, $%d, %d\n", i.i_rt, i.i_rs, EXT(i.i_imm));
		break;
	    case TSIM:
		printf("$%d, $%d, %#x\n", i.i_rt, i.i_rs, i.i_imm);
		break;
	    case TIM:
		printf("$%d, %#04x\n", i.i_rt, i.i_imm);
		break;
	    case TMEM:
		printf("$%d, %d($%d)\n", i.i_rt, i.i_imm, i.i_rs);
		break;
	    case NONE:
		break;
	    case BRAK:
		printf("%#x\n", i.j_jmp);
		break;
	    case S:
		printf("$%d\n", i.r_rs);
		break;
	    case SD:
		printf("$%d, $%d\n", i.r_rs, i.r_rd);
		break;
	    case D:
		printf("$%d\n", i.r_rd);
		break;
	    case ST:
		printf("$%d, $%d\n", i.r_rs, i.r_rt);
		break;
	    case DST:
		printf("$%d, $%d, $%d\n", i.r_rd, i.r_rs, i.r_rt);
		break;
	    case DTSH:
		printf("$%d, $%d, %d\n", i.r_rd, i.r_rt, i.r_shift);
		break;
	    case DTS:
		printf("$%d, $%d, $%d\n", i.r_rd, i.r_rt, i.r_rs);
		break;
	    case CO:
		puts("coprocessor instruction");
		break;
	    case UKWN:
	    default:
		puts("** Unknown instruction **");
	}
    }
    return EX_OK;
}