static int
decode_ssepfx(struct ud *u)
{
uint8_t idx = ((u->pfx_insn & 0xf) + 1) / 2;
if (u->le->table[idx] == 0) {
idx = 0;
}
if (idx && u->le->table[idx] != 0) {
/*
* "Consume" the prefix as a part of the opcode, so it is no
* longer exported as an instruction prefix.
*/
switch (u->pfx_insn) {
case 0xf2:
u->pfx_repne = 0;
break;
case 0xf3:
u->pfx_rep = 0;
u->pfx_repe = 0;
break;
case 0x66:
u->pfx_opr = 0;
break;
}
}
return decode_ext(u, u->le->table[idx]);
}
static int
decode_ssepfx(struct ud *u)
{
uint8_t idx;
uint8_t pfx;
/*
* String prefixes (f2, f3) take precedence over operand
* size prefix (66).
*/
pfx = u->pfx_str;
if (pfx == 0) {
pfx = u->pfx_opr;
}
idx = ((pfx & 0xf) + 1) / 2;
if (u->le->table[idx] == 0) {
idx = 0;
}
if (idx && u->le->table[idx] != 0) {
/*
* "Consume" the prefix as a part of the opcode, so it is no
* longer exported as an instruction prefix.
*/
u->pfx_str = 0;
if (pfx == 0x66) {
/*
* consume "66" only if it was used for decoding, leaving
* it to be used as an operands size override for some
* simd instructions.
*/
u->pfx_opr = 0;
}
}
return decode_ext(u, u->le->table[idx]);
}
/*
* decode_ext()
*
* Decode opcode extensions (if any)
*/
static int
decode_ext(struct ud *u, uint16_t ptr)
{
uint8_t idx = 0;
if ((ptr & 0x8000) == 0) {
return decode_insn(u, ptr);
}
u->le = &ud_lookup_table_list[(~0x8000 & ptr)];
if (u->le->type == UD_TAB__OPC_3DNOW) {
return decode_3dnow(u);
}
switch (u->le->type) {
case UD_TAB__OPC_MOD:
/* !11 = 0, 11 = 1 */
idx = (MODRM_MOD(modrm(u)) + 1) / 4;
break;
/* disassembly mode/operand size/address size based tables.
* 16 = 0,, 32 = 1, 64 = 2
*/
case UD_TAB__OPC_MODE:
idx = u->dis_mode / 32;
break;
case UD_TAB__OPC_OSIZE:
idx = eff_opr_mode(u->dis_mode, REX_W(u->pfx_rex), u->pfx_opr) / 32;
break;
case UD_TAB__OPC_ASIZE:
idx = eff_adr_mode(u->dis_mode, u->pfx_adr) / 32;
break;
case UD_TAB__OPC_X87:
idx = modrm(u) - 0xC0;
break;
case UD_TAB__OPC_VENDOR:
if (u->vendor == UD_VENDOR_ANY) {
/* choose a valid entry */
idx = (u->le->table[idx] != 0) ? 0 : 1;
} else if (u->vendor == UD_VENDOR_AMD) {
idx = 0;
} else {
idx = 1;
}
break;
case UD_TAB__OPC_RM:
idx = MODRM_RM(modrm(u));
break;
case UD_TAB__OPC_REG:
idx = MODRM_REG(modrm(u));
break;
case UD_TAB__OPC_SSE:
return decode_ssepfx(u);
default:
assert(!"not reached");
break;
}
return decode_ext(u, u->le->table[idx]);
}
int _tmain(int argc, _TCHAR* argv[])
{
std::vector<int> msg_old = {
0, 0, 1, 0, 0, 1, 0, 1,
0, 0, 0, 0, 1, 1, 0, 1,
0, 1, 0, 0, 1, 0, 1, 0, 1, 1 };
std::vector<int> msg = { 0, 2, 5, 0, 13, 4, 10, 15, 4 };
std::vector<int> bmsg = convertMessageToBinary(msg);
std::vector<int> msg_decode(bmsg.begin() + 4, bmsg.end());
decode_ext(msg_decode, msg_old);
return 0;
}
static int
decode_opcode(struct ud *u)
{
uint16_t ptr;
UD_ASSERT(u->le->type == UD_TAB__OPC_TABLE);
UD_RETURN_ON_ERROR(u);
u->primary_opcode = inp_curr(u);
ptr = u->le->table[inp_curr(u)];
if (ptr & 0x8000) {
u->le = &ud_lookup_table_list[ptr & ~0x8000];
if (u->le->type == UD_TAB__OPC_TABLE) {
inp_next(u);
return decode_opcode(u);
}
}
return decode_ext(u, ptr);
}
static __inline int
decode_opcode(struct ud *u)
{
uint16_t ptr;
assert(u->le->type == UD_TAB__OPC_TABLE);
inp_next(u);
if (u->error) {
return -1;
}
ptr = u->le->table[inp_curr(u)];
if (ptr & 0x8000) {
u->le = &ud_lookup_table_list[ptr & ~0x8000];
if (u->le->type == UD_TAB__OPC_TABLE) {
return decode_opcode(u);
}
}
return decode_ext(u, ptr);
}
