static DecodeStatus DecodeReturn(MCInst *MI, unsigned insn, uint64_t Address,
const void *Decoder)
{
DecodeStatus status;
unsigned rs1 = fieldFromInstruction_4(insn, 14, 5);
unsigned isImm = fieldFromInstruction_4(insn, 13, 1);
unsigned rs2 = 0;
unsigned simm13 = 0;
if (isImm)
simm13 = SignExtend32(fieldFromInstruction_4(insn, 0, 13), 13);
else
rs2 = fieldFromInstruction_4(insn, 0, 5);
// Decode RS1.
status = DecodeIntRegsRegisterClass(MI, rs1, Address, Decoder);
if (status != MCDisassembler_Success)
return status;
// Decode RS2 | SIMM13.
if (isImm)
MCInst_addOperand(MI, MCOperand_CreateImm(simm13));
else {
status = DecodeIntRegsRegisterClass(MI, rs2, Address, Decoder);
if (status != MCDisassembler_Success)
return status;
}
return MCDisassembler_Success;
}
static DecodeStatus DecodeExtSize(MCInst *Inst,
unsigned Insn, uint64_t Address, MCRegisterInfo *Decoder)
{
int Size = (int) Insn + 1;
MCInst_addOperand(Inst, MCOperand_CreateImm(SignExtend32(Size, 16)));
return MCDisassembler_Success;
}
static DecodeStatus DecodeJumpTargetMM(MCInst *Inst,
unsigned Insn, uint64_t Address, MCRegisterInfo *Decoder)
{
unsigned JumpOffset = fieldFromInstruction(Insn, 0, 26) << 1;
MCInst_addOperand(Inst, MCOperand_CreateImm(JumpOffset));
return MCDisassembler_Success;
}
static DecodeStatus DecodeLSAImm(MCInst *Inst,
unsigned Insn, uint64_t Address, MCRegisterInfo *Decoder)
{
// We add one to the immediate field as it was encoded as 'imm - 1'.
MCInst_addOperand(Inst, MCOperand_CreateImm(Insn + 1));
return MCDisassembler_Success;
}
static DecodeStatus DecodeMSA128Mem(MCInst *Inst, unsigned Insn,
uint64_t Address, MCRegisterInfo *Decoder)
{
int Offset = SignExtend32(fieldFromInstruction(Insn, 16, 10), 10);
unsigned Reg = fieldFromInstruction(Insn, 6, 5);
unsigned Base = fieldFromInstruction(Insn, 11, 5);
Reg = getReg(Decoder, Mips_MSA128BRegClassID, Reg);
Base = getReg(Decoder, Mips_GPR32RegClassID, Base);
MCInst_addOperand(Inst, MCOperand_CreateReg(Reg));
MCInst_addOperand(Inst, MCOperand_CreateReg(Base));
// MCInst_addOperand(Inst, MCOperand_CreateImm(Offset));
// The immediate field of an LD/ST instruction is scaled which means it must
// be multiplied (when decoding) by the size (in bytes) of the instructions'
// data format.
// .b - 1 byte
// .h - 2 bytes
// .w - 4 bytes
// .d - 8 bytes
switch(MCInst_getOpcode(Inst))
{
default:
//assert (0 && "Unexpected instruction");
return MCDisassembler_Fail;
break;
case Mips_LD_B:
case Mips_ST_B:
MCInst_addOperand(Inst, MCOperand_CreateImm(Offset));
break;
case Mips_LD_H:
case Mips_ST_H:
MCInst_addOperand(Inst, MCOperand_CreateImm(Offset << 1));
break;
case Mips_LD_W:
case Mips_ST_W:
MCInst_addOperand(Inst, MCOperand_CreateImm(Offset << 2));
break;
case Mips_LD_D:
case Mips_ST_D:
MCInst_addOperand(Inst, MCOperand_CreateImm(Offset << 3));
break;
}
return MCDisassembler_Success;
}
static DecodeStatus DecodeBranchTargetMM(MCInst *Inst,
unsigned Offset, uint64_t Address, MCRegisterInfo *Decoder)
{
unsigned BranchOffset = Offset & 0xffff;
BranchOffset = SignExtend32(BranchOffset << 1, 18);
MCInst_addOperand(Inst, MCOperand_CreateImm(BranchOffset));
return MCDisassembler_Success;
}
static DecodeStatus DecodeSIMM13(MCInst *MI, unsigned insn,
uint64_t Address, const void *Decoder)
{
unsigned tgt = SignExtend32(fieldFromInstruction_4(insn, 0, 13), 13);
MCInst_addOperand(MI, MCOperand_CreateImm(tgt));
return MCDisassembler_Success;
}
static DecodeStatus DecodeInsSize(MCInst *Inst,
unsigned Insn, uint64_t Address, MCRegisterInfo *Decoder)
{
// First we need to grab the pos(lsb) from MCInst.
int Pos = MCOperand_getImm(MCInst_getOperand(Inst, 2));
int Size = (int) Insn - Pos + 1;
MCInst_addOperand(Inst, MCOperand_CreateImm(SignExtend32(Size, 16)));
return MCDisassembler_Success;
}
static DecodeStatus DecodeCall(MCInst *MI, unsigned insn,
uint64_t Address, const void *Decoder)
{
unsigned tgt = fieldFromInstruction_4(insn, 0, 30);
tgt <<= 2;
MCInst_addOperand(MI, MCOperand_CreateImm(tgt));
return MCDisassembler_Success;
}
static DecodeStatus DecodeFMem(MCInst *Inst,
unsigned Insn, uint64_t Address, MCRegisterInfo *Decoder)
{
int Offset = SignExtend32(Insn & 0xffff, 16);
unsigned Reg = fieldFromInstruction(Insn, 16, 5);
unsigned Base = fieldFromInstruction(Insn, 21, 5);
Reg = getReg(Decoder, Mips_FGR64RegClassID, Reg);
Base = getReg(Decoder, Mips_GPR32RegClassID, Base);
MCInst_addOperand(Inst, MCOperand_CreateReg(Reg));
MCInst_addOperand(Inst, MCOperand_CreateReg(Base));
MCInst_addOperand(Inst, MCOperand_CreateImm(Offset));
return MCDisassembler_Success;
}
static DecodeStatus DecodeMem(MCInst *MI, unsigned insn, uint64_t Address,
const void *Decoder,
bool isLoad, DecodeFunc DecodeRD)
{
DecodeStatus status;
unsigned rd = fieldFromInstruction_4(insn, 25, 5);
unsigned rs1 = fieldFromInstruction_4(insn, 14, 5);
bool isImm = fieldFromInstruction_4(insn, 13, 1);
unsigned rs2 = 0;
unsigned simm13 = 0;
if (isImm)
simm13 = SignExtend32(fieldFromInstruction_4(insn, 0, 13), 13);
else
rs2 = fieldFromInstruction_4(insn, 0, 5);
if (isLoad) {
status = DecodeRD(MI, rd, Address, Decoder);
if (status != MCDisassembler_Success)
return status;
}
// Decode rs1.
status = DecodeIntRegsRegisterClass(MI, rs1, Address, Decoder);
if (status != MCDisassembler_Success)
return status;
// Decode imm|rs2.
if (isImm)
MCInst_addOperand(MI, MCOperand_CreateImm(simm13));
else {
status = DecodeIntRegsRegisterClass(MI, rs2, Address, Decoder);
if (status != MCDisassembler_Success)
return status;
}
if (!isLoad) {
status = DecodeRD(MI, rd, Address, Decoder);
if (status != MCDisassembler_Success)
return status;
}
return MCDisassembler_Success;
}
/// translateImmediate - Appends an immediate operand to an MCInst.
///
/// @param mcInst - The MCInst to append to.
/// @param immediate - The immediate value to append.
/// @param operand - The operand, as stored in the descriptor table.
/// @param insn - The internal instruction.
static void translateImmediate(MCInst *mcInst, uint64_t immediate,
const OperandSpecifier *operand, InternalInstruction *insn)
{
OperandType type;
MCOperand *segmentReg;
type = (OperandType)operand->type;
if (type == TYPE_RELv) {
//isBranch = true;
//pcrel = insn->startLocation + insn->immediateOffset + insn->immediateSize;
switch (insn->displacementSize) {
case 1:
if (immediate & 0x80)
immediate |= ~(0xffull);
break;
case 2:
if (immediate & 0x8000)
immediate |= ~(0xffffull);
break;
case 4:
if (immediate & 0x80000000)
immediate |= ~(0xffffffffull);
break;
case 8:
break;
default:
break;
}
} // By default sign-extend all X86 immediates based on their encoding.
else if (type == TYPE_IMM8 || type == TYPE_IMM16 || type == TYPE_IMM32 ||
type == TYPE_IMM64) {
uint32_t Opcode = MCInst_getOpcode(mcInst);
switch (operand->encoding) {
default:
break;
case ENCODING_IB:
// Special case those X86 instructions that use the imm8 as a set of
// bits, bit count, etc. and are not sign-extend.
if (Opcode != X86_BLENDPSrri && Opcode != X86_BLENDPDrri &&
Opcode != X86_PBLENDWrri && Opcode != X86_MPSADBWrri &&
Opcode != X86_DPPSrri && Opcode != X86_DPPDrri &&
Opcode != X86_INSERTPSrr && Opcode != X86_VBLENDPSYrri &&
Opcode != X86_VBLENDPSYrmi && Opcode != X86_VBLENDPDYrri &&
Opcode != X86_VBLENDPDYrmi && Opcode != X86_VPBLENDWrri &&
Opcode != X86_VMPSADBWrri && Opcode != X86_VDPPSYrri &&
Opcode != X86_VDPPSYrmi && Opcode != X86_VDPPDrri &&
Opcode != X86_VINSERTPSrr && Opcode != X86_INT)
if(immediate & 0x80)
immediate |= ~(0xffull);
break;
case ENCODING_IW:
if(immediate & 0x8000)
immediate |= ~(0xffffull);
break;
case ENCODING_ID:
if(immediate & 0x80000000)
immediate |= ~(0xffffffffull);
break;
case ENCODING_IO:
break;
}
}
switch (type) {
case TYPE_XMM32:
case TYPE_XMM64:
case TYPE_XMM128:
MCInst_addOperand(mcInst, MCOperand_CreateReg(X86_XMM0 + ((uint32_t)immediate >> 4)));
return;
case TYPE_XMM256:
MCInst_addOperand(mcInst, MCOperand_CreateReg(X86_YMM0 + ((uint32_t)immediate >> 4)));
return;
case TYPE_XMM512:
MCInst_addOperand(mcInst, MCOperand_CreateReg(X86_ZMM0 + ((uint32_t)immediate >> 4)));
return;
case TYPE_REL8:
if(immediate & 0x80)
immediate |= ~(0xffull);
break;
case TYPE_REL32:
case TYPE_REL64:
if(immediate & 0x80000000)
immediate |= ~(0xffffffffull);
break;
default:
// operand is 64 bits wide. Do nothing.
break;
}
MCInst_addOperand(mcInst, MCOperand_CreateImm(immediate));
if (type == TYPE_MOFFS8 || type == TYPE_MOFFS16 ||
type == TYPE_MOFFS32 || type == TYPE_MOFFS64) {
segmentReg = MCOperand_CreateReg(segmentRegnums[insn->segmentOverride]);
MCInst_addOperand(mcInst, segmentReg);
}
}