disasm.c

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	    }
	    break;

	case4(050):
            opx->offset = gets8(data++);
            opx->segment |= SEG_RELATIVE;
	    break;

	case4(054):
	    opx->offset = getu64(data);
	    data += 8;
	    break;

	case4(060):
            opx->offset = gets16(data);
	    data += 2;
            opx->segment |= SEG_RELATIVE;
            opx->segment &= ~SEG_32BIT;
	    break;

	case4(064):
            opx->segment |= SEG_RELATIVE;
	    if (osize == 16) {
		opx->offset = gets16(data);
		data += 2;
                opx->segment &= ~(SEG_32BIT|SEG_64BIT);
	    } else if (osize == 32) {
		opx->offset = gets32(data);
		data += 4;
                opx->segment &= ~SEG_64BIT;
                opx->segment |= SEG_32BIT;
	    }
            if (segsize != osize) {
                opx->type =
                    (opx->type & ~SIZE_MASK)
                    | ((osize == 16) ? BITS16 : BITS32);
            }
	    break;

	case4(070):
            opx->offset = gets32(data);
	    data += 4;
            opx->segment |= SEG_32BIT | SEG_RELATIVE;
	    break;

	case4(0100):
	case4(0110):
	case4(0120):
	case4(0130):
	{
	    int modrm = *data++;
            opx->segment |= SEG_RMREG;
            data = do_ea(data, modrm, asize, segsize,
			 &ins->oprs[(c >> 3) & 3], ins);
	    if (!data)
		return false;
            opx->basereg = ((modrm >> 3)&7)+
		(ins->rex & REX_R ? 8 : 0);
	    break;
	}

	case4(0140):
	    if (s_field_for == (c & 3)) {
		opx->offset = gets8(data);
		data++;
	    } else {
		opx->offset = getu16(data);
		data += 2;
	    }
	    break;

	case4(0144):
	case4(0154):
	    s_field_for = (*data & 0x02) ? c & 3 : -1;
	    if ((*data++ & ~0x02) != *r++)
		return false;
	    break;

	case4(0150):
	    if (s_field_for == (c & 3)) {
		opx->offset = gets8(data);
		data++;
	    } else {
		opx->offset = getu32(data);
		data += 4;
	    }
	    break;

	case4(0160):
	    ins->rex |= REX_D;
	    ins->drexdst = c & 3;
	    break;

	case4(0164):
	    ins->rex |= REX_D|REX_OC;
	    ins->drexdst = c & 3;
	    break;

	case 0171:
	    data = do_drex(data, ins);
	    if (!data)
		return false;
	    break;

	case 0172:
	{
	    uint8_t ximm = *data++;
	    c = *r++;
	    ins->oprs[c >> 3].basereg = (ximm >> 4) & regmask;
	    ins->oprs[c >> 3].segment |= SEG_RMREG;
	    ins->oprs[c & 7].offset = ximm & 15;
	}
	break;

	case 0173:
	{
	    uint8_t ximm = *data++;
	    c = *r++;

	    if ((c ^ ximm) & 15)
		return false;

	    ins->oprs[c >> 4].basereg = (ximm >> 4) & regmask;
	    ins->oprs[c >> 4].segment |= SEG_RMREG;
	}
	break;

	case 0174:
	{
	    uint8_t ximm = *data++;
	    c = *r++;

	    ins->oprs[c].basereg = (ximm >> 4) & regmask;
	    ins->oprs[c].segment |= SEG_RMREG;
	}
	break;

	case4(0200):
	case4(0204):
	case4(0210):
	case4(0214):
	case4(0220):
	case4(0224):
	case4(0230):
	case4(0234):
	{
            int modrm = *data++;
            if (((modrm >> 3) & 07) != (c & 07))
                return false;   /* spare field doesn't match up */
            data = do_ea(data, modrm, asize, segsize,
                         &ins->oprs[(c >> 3) & 07], ins);
	    if (!data)
		return false;
	    break;
	}

	case4(0260):
	{
	    int vexm   = *r++;
	    int vexwlp = *r++;
	    ins->rex |= REX_V;
	    if ((prefix->rex & (REX_V|REX_D|REX_P)) != REX_V)
		return false;

	    if ((vexm & 0x1f) != prefix->vex_m)
		return false;

	    switch (vexwlp & 030) {
	    case 000:
		if (prefix->rex & REX_W)
		    return false;
		break;
	    case 010:
		if (!(prefix->rex & REX_W))
		    return false;
		ins->rex &= ~REX_W;
		break;
	    case 020:		/* VEX.W is a don't care */
		ins->rex &= ~REX_W;
		break;
	    case 030:
		break;
	    }

	    if ((vexwlp & 007) != prefix->vex_lp)
		return false;

	    opx->segment |= SEG_RMREG;
	    opx->basereg = prefix->vex_v;
	    vex_ok = true;
	    break;
	}

	case 0270:
	{
	    int vexm   = *r++;
	    int vexwlp = *r++;
	    ins->rex |= REX_V;
	    if ((prefix->rex & (REX_V|REX_D|REX_P)) != REX_V)
		return false;

	    if ((vexm & 0x1f) != prefix->vex_m)
		return false;

	    switch (vexwlp & 030) {
	    case 000:
		if (ins->rex & REX_W)
		    return false;
		break;
	    case 010:
		if (!(ins->rex & REX_W))
		    return false;
		break;
	    default:
		break;		/* Need to do anything special here? */
	    }

	    if ((vexwlp & 007) != prefix->vex_lp)
		return false;

	    if (prefix->vex_v != 0)
		return false;

	    vex_ok = true;
	    break;
	}

	case 0310:
            if (asize != 16)
                return false;
            else
                a_used = true;
	    break;

	case 0311:
            if (asize == 16)
                return false;
            else
                a_used = true;
	    break;

	case 0312:
            if (asize != segsize)
                return false;
            else
                a_used = true;
	    break;

	case 0313:
	    if (asize != 64)
		return false;
	    else
		a_used = true;
	    break;

	case 0314:
	    if (prefix->rex & REX_B)
		return false;
	    break;

	case 0315:
	    if (prefix->rex & REX_X)
		return false;
	    break;

	case 0316:
	    if (prefix->rex & REX_R)
		return false;
	    break;

	case 0317:
	    if (prefix->rex & REX_W)
		return false;
	    break;

	case 0320:
            if (osize != 16)
                return false;
            else
                o_used = true;
	    break;

	case 0321:
            if (osize != 32)
                return false;
            else
                o_used = true;
	    break;

	case 0322:
            if (osize != (segsize == 16) ? 16 : 32)
                return false;
            else
                o_used = true;
	    break;

	case 0323:
	    ins->rex |= REX_W;	/* 64-bit only instruction */
	    osize = 64;
	    o_used = true;
	    break;

	case 0324:
	    if (!(ins->rex & (REX_P|REX_W)) || osize != 64)
		return false;
	    o_used = true;
	    break;

	case 0330:
	{
            int t = *r++, d = *data++;
            if (d < t || d > t + 15)
                return false;
            else
                ins->condition = d - t;
	    break;
	}

	case 0331:
            if (prefix->rep)
                return false;
	    break;

	case 0332:
	    if (prefix->rep != 0xF2)
		return false;
	    drep = 0;
	    break;

	case 0333:
            if (prefix->rep != 0xF3)
                return false;
            drep = 0;
	    break;

	case 0334:
	    if (lock) {
		ins->rex |= REX_R;
		lock = 0;
	    }
	    break;

	case 0335:
            if (drep == P_REP)
                drep = P_REPE;
	    break;

	case 0336:
	case 0337:
	    break;

	case 0340:
	    return false;

	case4(0344):
	    ins->oprs[0].basereg = (*data++ >> 3) & 7;
	    break;

	case 0360:
	    if (prefix->osp || prefix->rep)
		return false;
	    break;

	case 0361:
	    if (!prefix->osp || prefix->rep)
		return false;
	    o_used = true;
	    break;

	case 0362:
	    if (prefix->osp || prefix->rep != 0xf2)
		return false;
	    drep = 0;
	    break;

	case 0363:
	    if (prefix->osp || prefix->rep != 0xf3)
		return false;
	    drep = 0;
	    break;

	case 0364:
	    if (prefix->osp)
		return false;
	    break;

	case 0365:
	    if (prefix->asp)
		return false;
	    break;

	case 0366:
	    if (!prefix->osp)
		return false;
	    o_used = true;
	    break;

	case 0367:
	    if (!prefix->asp)
		return false;
	    a_used = true;
	    break;

	default:
	    return false;	/* Unknown code */
	}
    }

    if (!vex_ok && (ins->rex & REX_V))
	return false;

    /* REX cannot be combined with DREX or VEX */
    if ((ins->rex & (REX_D|REX_V)) && (prefix->rex & REX_P))
	return false;

    /*
     * Check for unused rep or a/o prefixes.
     */
    for (i = 0; i < t->operands; i++) {
	if (ins->oprs[i].segment != SEG_RMREG)
	    a_used = true;
    }

    if (lock) {
	if (ins->prefixes[PPS_LREP])
	    return false;
	ins->prefixes[PPS_LREP] = P_LOCK;
    }
    if (drep) {
	if (ins->prefixes[PPS_LREP])
	    return false;
        ins->prefixes[PPS_LREP] = drep;
    }
    if (!o_used) {
	if (osize != ((segsize == 16) ? 16 : 32)) {
	    enum prefixes pfx = 0;

	    switch (osize) {
	    case 16:
		pfx = P_O16;
		break;
	    case 32:
		pfx = P_O32;
		break;
	    case 64:
		pfx = P_O64;
		break;
	    }

	    if (ins->prefixes[PPS_OSIZE])
		return false;
	    ins->prefixes[PPS_OSIZE] = pfx;
	}
    }
    if (!a_used && asize != segsize) {
	if (ins->prefixes[PPS_ASIZE])
	    return false;
        ins->prefixes[PPS_ASIZE] = asize == 16 ? P_A16 : P_A32;
    }

    /* Fix: check for redundant REX prefixes */

    return data - origdata;
}

/* Condition names for disassembly, sorted by x86 code */
static const char * const condition_name[16] = {
    "o", "no", "c", "nc", "z", "nz", "na", "a",
    "s", "ns", "pe", "po", "l", "nl", "ng", "g"
};

int32_t disasm(uint8_t *data, char *output, int outbufsize, int segsize,
            int32_t offset, int autosync, uint32_t prefer)
{
    const struct itemplate * const *p, * const *best_p;
    const struct disasm_index *ix;
    uint8_t *dp;
    int length, best_length = 0;