citra/src/common/x64/emitter.cpp

// Copyright (C) 2003 Dolphin Project.

// 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, version 2.0 or later versions.

// 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 2.0 for more details.

// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/

// Official SVN repository and contact information can be found at
// http://code.google.com/p/dolphin-emu/

#include <cinttypes>
#include <cstring>

#include "common/assert.h"
#include "common/logging/log.h"
#include "common/memory_util.h"

#include "abi.h"
#include "cpu_detect.h"
#include "emitter.h"

namespace Gen {

struct NormalOpDef {
    u8 toRm8, toRm32, fromRm8, fromRm32, imm8, imm32, simm8, eaximm8, eaximm32, ext;
};

// 0xCC is code for invalid combination of immediates
static const NormalOpDef normalops[11] = {
    {0x00, 0x01, 0x02, 0x03, 0x80, 0x81, 0x83, 0x04, 0x05, 0}, // ADD
    {0x10, 0x11, 0x12, 0x13, 0x80, 0x81, 0x83, 0x14, 0x15, 2}, // ADC

    {0x28, 0x29, 0x2A, 0x2B, 0x80, 0x81, 0x83, 0x2C, 0x2D, 5}, // SUB
    {0x18, 0x19, 0x1A, 0x1B, 0x80, 0x81, 0x83, 0x1C, 0x1D, 3}, // SBB

    {0x20, 0x21, 0x22, 0x23, 0x80, 0x81, 0x83, 0x24, 0x25, 4}, // AND
    {0x08, 0x09, 0x0A, 0x0B, 0x80, 0x81, 0x83, 0x0C, 0x0D, 1}, // OR

    {0x30, 0x31, 0x32, 0x33, 0x80, 0x81, 0x83, 0x34, 0x35, 6}, // XOR
    {0x88, 0x89, 0x8A, 0x8B, 0xC6, 0xC7, 0xCC, 0xCC, 0xCC, 0}, // MOV

    {0x84, 0x85, 0x84, 0x85, 0xF6, 0xF7, 0xCC, 0xA8, 0xA9, 0}, // TEST (to == from)
    {0x38, 0x39, 0x3A, 0x3B, 0x80, 0x81, 0x83, 0x3C, 0x3D, 7}, // CMP

    {0x86, 0x87, 0x86, 0x87, 0xCC, 0xCC, 0xCC, 0xCC, 0xCC, 7}, // XCHG
};

enum NormalSSEOps {
    sseCMP = 0xC2,
    sseADD = 0x58,  // ADD
    sseSUB = 0x5C,  // SUB
    sseAND = 0x54,  // AND
    sseANDN = 0x55, // ANDN
    sseOR = 0x56,
    sseXOR = 0x57,
    sseMUL = 0x59,         // MUL
    sseDIV = 0x5E,         // DIV
    sseMIN = 0x5D,         // MIN
    sseMAX = 0x5F,         // MAX
    sseCOMIS = 0x2F,       // COMIS
    sseUCOMIS = 0x2E,      // UCOMIS
    sseSQRT = 0x51,        // SQRT
    sseRSQRT = 0x52,       // RSQRT (NO DOUBLE PRECISION!!!)
    sseRCP = 0x53,         // RCP
    sseMOVAPfromRM = 0x28, // MOVAP from RM
    sseMOVAPtoRM = 0x29,   // MOVAP to RM
    sseMOVUPfromRM = 0x10, // MOVUP from RM
    sseMOVUPtoRM = 0x11,   // MOVUP to RM
    sseMOVLPfromRM = 0x12,
    sseMOVLPtoRM = 0x13,
    sseMOVHPfromRM = 0x16,
    sseMOVHPtoRM = 0x17,
    sseMOVHLPS = 0x12,
    sseMOVLHPS = 0x16,
    sseMOVDQfromRM = 0x6F,
    sseMOVDQtoRM = 0x7F,
    sseMASKMOVDQU = 0xF7,
    sseLDDQU = 0xF0,
    sseSHUF = 0xC6,
    sseMOVNTDQ = 0xE7,
    sseMOVNTP = 0x2B,
    sseHADD = 0x7C,
};

void XEmitter::SetCodePtr(u8* ptr) {
    code = ptr;
}

const u8* XEmitter::GetCodePtr() const {
    return code;
}

u8* XEmitter::GetWritableCodePtr() {
    return code;
}

void XEmitter::Write8(u8 value) {
    *code++ = value;
}

void XEmitter::Write16(u16 value) {
    std::memcpy(code, &value, sizeof(u16));
    code += sizeof(u16);
}

void XEmitter::Write32(u32 value) {
    std::memcpy(code, &value, sizeof(u32));
    code += sizeof(u32);
}

void XEmitter::Write64(u64 value) {
    std::memcpy(code, &value, sizeof(u64));
    code += sizeof(u64);
}

void XEmitter::ReserveCodeSpace(int bytes) {
    for (int i = 0; i < bytes; i++)
        *code++ = 0xCC;
}

const u8* XEmitter::AlignCode4() {
    int c = int((u64)code & 3);
    if (c)
        ReserveCodeSpace(4 - c);
    return code;
}

const u8* XEmitter::AlignCode16() {
    int c = int((u64)code & 15);
    if (c)
        ReserveCodeSpace(16 - c);
    return code;
}

const u8* XEmitter::AlignCodePage() {
    int c = int((u64)code & 4095);
    if (c)
        ReserveCodeSpace(4096 - c);
    return code;
}

// This operation modifies flags; check to see the flags are locked.
// If the flags are locked, we should immediately and loudly fail before
// causing a subtle JIT bug.
void XEmitter::CheckFlags() {
    ASSERT_MSG(!flags_locked, "Attempt to modify flags while flags locked!");
}

void XEmitter::WriteModRM(int mod, int reg, int rm) {
    Write8((u8)((mod << 6) | ((reg & 7) << 3) | (rm & 7)));
}

void XEmitter::WriteSIB(int scale, int index, int base) {
    Write8((u8)((scale << 6) | ((index & 7) << 3) | (base & 7)));
}

void OpArg::WriteRex(XEmitter* emit, int opBits, int bits, int customOp) const {
    if (customOp == -1)
        customOp = operandReg;
#ifdef ARCHITECTURE_x86_64
    u8 op = 0x40;
    // REX.W (whether operation is a 64-bit operation)
    if (opBits == 64)
        op |= 8;
    // REX.R (whether ModR/M reg field refers to R8-R15.
    if (customOp & 8)
        op |= 4;
    // REX.X (whether ModR/M SIB index field refers to R8-R15)
    if (indexReg & 8)
        op |= 2;
    // REX.B (whether ModR/M rm or SIB base or opcode reg field refers to R8-R15)
    if (offsetOrBaseReg & 8)
        op |= 1;
    // Write REX if wr have REX bits to write, or if the operation accesses
    // SIL, DIL, BPL, or SPL.
    if (op != 0x40 || (scale == SCALE_NONE && bits == 8 && (offsetOrBaseReg & 0x10c) == 4) ||
        (opBits == 8 && (customOp & 0x10c) == 4)) {
        emit->Write8(op);
        // Check the operation doesn't access AH, BH, CH, or DH.
        DEBUG_ASSERT((offsetOrBaseReg & 0x100) == 0);
        DEBUG_ASSERT((customOp & 0x100) == 0);
    }
#else
    DEBUG_ASSERT(opBits != 64);
    DEBUG_ASSERT((customOp & 8) == 0 || customOp == -1);
    DEBUG_ASSERT((indexReg & 8) == 0);
    DEBUG_ASSERT((offsetOrBaseReg & 8) == 0);
    DEBUG_ASSERT(opBits != 8 || (customOp & 0x10c) != 4 || customOp == -1);
    DEBUG_ASSERT(scale == SCALE_ATREG || bits != 8 || (offsetOrBaseReg & 0x10c) != 4);
#endif
}

void OpArg::WriteVex(XEmitter* emit, X64Reg regOp1, X64Reg regOp2, int L, int pp, int mmmmm,
                     int W) const {
    int R = !(regOp1 & 8);
    int X = !(indexReg & 8);
    int B = !(offsetOrBaseReg & 8);

    int vvvv = (regOp2 == X64Reg::INVALID_REG) ? 0xf : (regOp2 ^ 0xf);

    // do we need any VEX fields that only appear in the three-byte form?
    if (X == 1 && B == 1 && W == 0 && mmmmm == 1) {
        u8 RvvvvLpp = (R << 7) | (vvvv << 3) | (L << 2) | pp;
        emit->Write8(0xC5);
        emit->Write8(RvvvvLpp);
    } else {
        u8 RXBmmmmm = (R << 7) | (X << 6) | (B << 5) | mmmmm;
        u8 WvvvvLpp = (W << 7) | (vvvv << 3) | (L << 2) | pp;
        emit->Write8(0xC4);
        emit->Write8(RXBmmmmm);
        emit->Write8(WvvvvLpp);
    }
}

void OpArg::WriteRest(XEmitter* emit, int extraBytes, X64Reg _operandReg,
                      bool warn_64bit_offset) const {
    if (_operandReg == INVALID_REG)
        _operandReg = (X64Reg)this->operandReg;
    int mod = 0;
    int ireg = indexReg;
    bool SIB = false;
    int _offsetOrBaseReg = this->offsetOrBaseReg;

    if (scale == SCALE_RIP) // Also, on 32-bit, just an immediate address
    {
        // Oh, RIP addressing.
        _offsetOrBaseReg = 5;
        emit->WriteModRM(0, _operandReg, _offsetOrBaseReg);
// TODO : add some checks
#ifdef ARCHITECTURE_x86_64
        u64 ripAddr = (u64)emit->GetCodePtr() + 4 + extraBytes;
        s64 distance = (s64)offset - (s64)ripAddr;
        ASSERT_MSG((distance < 0x80000000LL && distance >= -0x80000000LL) || !warn_64bit_offset,
                   "WriteRest: op out of range (0x%" PRIx64 " uses 0x%" PRIx64 ")", ripAddr,
                   offset);
        s32 offs = (s32)distance;
        emit->Write32((u32)offs);
#else
        emit->Write32((u32)offset);
#endif
        return;
    }

    if (scale == 0) {
        // Oh, no memory, Just a reg.
        mod = 3; // 11
    } else if (scale >= 1) {
        // Ah good, no scaling.
        if (scale == SCALE_ATREG && !((_offsetOrBaseReg & 7) == 4 || (_offsetOrBaseReg & 7) == 5)) {
            // Okay, we're good. No SIB necessary.
            int ioff = (int)offset;
            if (ioff == 0) {
                mod = 0;
            } else if (ioff < -128 || ioff > 127) {
                mod = 2; // 32-bit displacement
            } else {
                mod = 1; // 8-bit displacement
            }
        } else if (scale >= SCALE_NOBASE_2 && scale <= SCALE_NOBASE_8) {
            SIB = true;
            mod = 0;
            _offsetOrBaseReg = 5;
        } else // if (scale != SCALE_ATREG)
        {
            if ((_offsetOrBaseReg & 7) == 4) // this would occupy the SIB encoding :(
            {
                // So we have to fake it with SIB encoding :(
                SIB = true;
            }

            if (scale >= SCALE_1 && scale < SCALE_ATREG) {
                SIB = true;
            }

            if (scale == SCALE_ATREG && ((_offsetOrBaseReg & 7) == 4)) {
                SIB = true;
                ireg = _offsetOrBaseReg;
            }

            // Okay, we're fine. Just disp encoding.
            // We need displacement. Which size?
            int ioff = (int)(s64)offset;
            if (ioff < -128 || ioff > 127) {
                mod = 2; // 32-bit displacement
            } else {
                mod = 1; // 8-bit displacement
            }
        }
    }

    // Okay. Time to do the actual writing
    // ModRM byte:
    int oreg = _offsetOrBaseReg;
    if (SIB)
        oreg = 4;

    // TODO(ector): WTF is this if about? I don't remember writing it :-)
    // if (RIP)
    //    oreg = 5;

    emit->WriteModRM(mod, _operandReg & 7, oreg & 7);

    if (SIB) {
        // SIB byte
        int ss;
        switch (scale) {
        case SCALE_NONE:
            _offsetOrBaseReg = 4;
            ss = 0;
            break; // RSP
        case SCALE_1:
            ss = 0;
            break;
        case SCALE_2:
            ss = 1;
            break;
        case SCALE_4:
            ss = 2;
            break;
        case SCALE_8:
            ss = 3;
            break;
        case SCALE_NOBASE_2:
            ss = 1;
            break;
        case SCALE_NOBASE_4:
            ss = 2;
            break;
        case SCALE_NOBASE_8:
            ss = 3;
            break;
        case SCALE_ATREG:
            ss = 0;
            break;
        default:
            ASSERT_MSG(0, "Invalid scale for SIB byte");
            ss = 0;
            break;
        }
        emit->Write8((u8)((ss << 6) | ((ireg & 7) << 3) | (_offsetOrBaseReg & 7)));
    }

    if (mod == 1) // 8-bit disp
    {
        emit->Write8((u8)(s8)(s32)offset);
    } else if (mod == 2 || (scale >= SCALE_NOBASE_2 && scale <= SCALE_NOBASE_8)) // 32-bit disp
    {
        emit->Write32((u32)offset);
    }
}

// W = operand extended width (1 if 64-bit)
// R = register# upper bit
// X = scale amnt upper bit
// B = base register# upper bit
void XEmitter::Rex(int w, int r, int x, int b) {
    w = w ? 1 : 0;
    r = r ? 1 : 0;
    x = x ? 1 : 0;
    b = b ? 1 : 0;
    u8 rx = (u8)(0x40 | (w << 3) | (r << 2) | (x << 1) | (b));
    if (rx != 0x40)
        Write8(rx);
}

void XEmitter::JMP(const u8* addr, bool force5Bytes) {
    u64 fn = (u64)addr;
    if (!force5Bytes) {
        s64 distance = (s64)(fn - ((u64)code + 2));
        ASSERT_MSG(distance >= -0x80 && distance < 0x80,
                   "Jump target too far away, needs force5Bytes = true");
        // 8 bits will do
        Write8(0xEB);
        Write8((u8)(s8)distance);
    } else {
        s64 distance = (s64)(fn - ((u64)code + 5));

        ASSERT_MSG(distance >= -0x80000000LL && distance < 0x80000000LL,
                   "Jump target too far away, needs indirect register");
        Write8(0xE9);
        Write32((u32)(s32)distance);
    }
}

void XEmitter::JMPptr(const OpArg& arg2) {
    OpArg arg = arg2;
    if (arg.IsImm())
        ASSERT_MSG(0, "JMPptr - Imm argument");
    arg.operandReg = 4;
    arg.WriteRex(this, 0, 0);
    Write8(0xFF);
    arg.WriteRest(this);
}

// Can be used to trap other processors, before overwriting their code
// not used in dolphin
void XEmitter::JMPself() {
    Write8(0xEB);
    Write8(0xFE);
}

void XEmitter::CALLptr(OpArg arg) {
    if (arg.IsImm())
        ASSERT_MSG(0, "CALLptr - Imm argument");
    arg.operandReg = 2;
    arg.WriteRex(this, 0, 0);
    Write8(0xFF);
    arg.WriteRest(this);
}

void XEmitter::CALL(const void* fnptr) {
    u64 distance = u64(fnptr) - (u64(code) + 5);
    ASSERT_MSG(distance < 0x0000000080000000ULL || distance >= 0xFFFFFFFF80000000ULL,
               "CALL out of range (%p calls %p)", code, fnptr);
    Write8(0xE8);
    Write32(u32(distance));
}

FixupBranch XEmitter::CALL() {
    FixupBranch branch;
    branch.type = 1;
    branch.ptr = code + 5;

    Write8(0xE8);
    Write32(0);

    return branch;
}

FixupBranch XEmitter::J(bool force5bytes) {
    FixupBranch branch;
    branch.type = force5bytes ? 1 : 0;
    branch.ptr = code + (force5bytes ? 5 : 2);
    if (!force5bytes) {
        // 8 bits will do
        Write8(0xEB);
        Write8(0);
    } else {
        Write8(0xE9);
        Write32(0);
    }
    return branch;
}

FixupBranch XEmitter::J_CC(CCFlags conditionCode, bool force5bytes) {
    FixupBranch branch;
    branch.type = force5bytes ? 1 : 0;
    branch.ptr = code + (force5bytes ? 6 : 2);
    if (!force5bytes) {
        // 8 bits will do
        Write8(0x70 + conditionCode);
        Write8(0);
    } else {
        Write8(0x0F);
        Write8(0x80 + conditionCode);
        Write32(0);
    }
    return branch;
}

void XEmitter::J_CC(CCFlags conditionCode, const u8* addr, bool force5bytes) {
    u64 fn = (u64)addr;
    s64 distance = (s64)(fn - ((u64)code + 2));
    if (distance < -0x80 || distance >= 0x80 || force5bytes) {
        distance = (s64)(fn - ((u64)code + 6));
        ASSERT_MSG(distance >= -0x80000000LL && distance < 0x80000000LL,
                   "Jump target too far away, needs indirect register");
        Write8(0x0F);
        Write8(0x80 + conditionCode);
        Write32((u32)(s32)distance);
    } else {
        Write8(0x70 + conditionCode);
        Write8((u8)(s8)distance);
    }
}

void XEmitter::SetJumpTarget(const FixupBranch& branch) {
    if (branch.type == 0) {
        s64 distance = (s64)(code - branch.ptr);
        ASSERT_MSG(distance >= -0x80 && distance < 0x80,
                   "Jump target too far away, needs force5Bytes = true");
        branch.ptr[-1] = (u8)(s8)distance;
    } else if (branch.type == 1) {
        s64 distance = (s64)(code - branch.ptr);
        ASSERT_MSG(distance >= -0x80000000LL && distance < 0x80000000LL,
                   "Jump target too far away, needs indirect register");
        ((s32*)branch.ptr)[-1] = (s32)distance;
    }
}

void XEmitter::SetJumpTarget(const FixupBranch& branch, const u8* target) {
    if (branch.type == 0) {
        s64 distance = (s64)(target - branch.ptr);
        ASSERT_MSG(distance >= -0x80 && distance < 0x80,
                   "Jump target too far away, needs force5Bytes = true");
        branch.ptr[-1] = (u8)(s8)distance;
    } else if (branch.type == 1) {
        s64 distance = (s64)(target - branch.ptr);
        ASSERT_MSG(distance >= -0x80000000LL && distance < 0x80000000LL,
                   "Jump target too far away, needs indirect register");
        ((s32*)branch.ptr)[-1] = (s32)distance;
    }
}

// Single byte opcodes
// There is no PUSHAD/POPAD in 64-bit mode.
void XEmitter::INT3() {
    Write8(0xCC);
}
void XEmitter::RET() {
    Write8(0xC3);
}
void XEmitter::RET_FAST() {
    Write8(0xF3);
    Write8(0xC3);
} // two-byte return (rep ret) - recommended by AMD optimization manual for the case of jumping to a
  // ret

// The first sign of decadence: optimized NOPs.
void XEmitter::NOP(size_t size) {
    DEBUG_ASSERT((int)size > 0);
    while (true) {
        switch (size) {
        case 0:
            return;
        case 1:
            Write8(0x90);
            return;
        case 2:
            Write8(0x66);
            Write8(0x90);
            return;
        case 3:
            Write8(0x0F);
            Write8(0x1F);
            Write8(0x00);
            return;
        case 4:
            Write8(0x0F);
            Write8(0x1F);
            Write8(0x40);
            Write8(0x00);
            return;
        case 5:
            Write8(0x0F);
            Write8(0x1F);
            Write8(0x44);
            Write8(0x00);
            Write8(0x00);
            return;
        case 6:
            Write8(0x66);
            Write8(0x0F);
            Write8(0x1F);
            Write8(0x44);
            Write8(0x00);
            Write8(0x00);
            return;
        case 7:
            Write8(0x0F);
            Write8(0x1F);
            Write8(0x80);
            Write8(0x00);
            Write8(0x00);
            Write8(0x00);
            Write8(0x00);
            return;
        case 8:
            Write8(0x0F);
            Write8(0x1F);
            Write8(0x84);
            Write8(0x00);
            Write8(0x00);
            Write8(0x00);
            Write8(0x00);
            Write8(0x00);
            return;
        case 9:
            Write8(0x66);
            Write8(0x0F);
            Write8(0x1F);
            Write8(0x84);
            Write8(0x00);
            Write8(0x00);
            Write8(0x00);
            Write8(0x00);
            Write8(0x00);
            return;
        case 10:
            Write8(0x66);
            Write8(0x66);
            Write8(0x0F);
            Write8(0x1F);
            Write8(0x84);
            Write8(0x00);
            Write8(0x00);
            Write8(0x00);
            Write8(0x00);
            Write8(0x00);
            return;
        default:
            // Even though x86 instructions are allowed to be up to 15 bytes long,
            // AMD advises against using NOPs longer than 11 bytes because they
            // carry a performance penalty on CPUs older than AMD family 16h.
            Write8(0x66);
            Write8(0x66);
            Write8(0x66);
            Write8(0x0F);
            Write8(0x1F);
            Write8(0x84);
            Write8(0x00);
            Write8(0x00);
            Write8(0x00);
            Write8(0x00);
            Write8(0x00);
            size -= 11;
            continue;
        }
    }
}

void XEmitter::PAUSE() {
    Write8(0xF3);
    NOP();
} // use in tight spinloops for energy saving on some cpu
void XEmitter::CLC() {
    CheckFlags();
    Write8(0xF8);
} // clear carry
void XEmitter::CMC() {
    CheckFlags();
    Write8(0xF5);
} // flip carry
void XEmitter::STC() {
    CheckFlags();
    Write8(0xF9);
} // set carry

// TODO: xchg ah, al ???
void XEmitter::XCHG_AHAL() {
    Write8(0x86);
    Write8(0xe0);
    // alt. 86 c4
}

// These two can not be executed on early Intel 64-bit CPU:s, only on AMD!
void XEmitter::LAHF() {
    Write8(0x9F);
}
void XEmitter::SAHF() {
    CheckFlags();
    Write8(0x9E);
}

void XEmitter::PUSHF() {
    Write8(0x9C);
}
void XEmitter::POPF() {
    CheckFlags();
    Write8(0x9D);
}

void XEmitter::LFENCE() {
    Write8(0x0F);
    Write8(0xAE);
    Write8(0xE8);
}
void XEmitter::MFENCE() {
    Write8(0x0F);
    Write8(0xAE);
    Write8(0xF0);
}
void XEmitter::SFENCE() {
    Write8(0x0F);
    Write8(0xAE);
    Write8(0xF8);
}

void XEmitter::WriteSimple1Byte(int bits, u8 byte, X64Reg reg) {
    if (bits == 16)
        Write8(0x66);
    Rex(bits == 64, 0, 0, (int)reg >> 3);
    Write8(byte + ((int)reg & 7));
}

void XEmitter::WriteSimple2Byte(int bits, u8 byte1, u8 byte2, X64Reg reg) {
    if (bits == 16)
        Write8(0x66);
    Rex(bits == 64, 0, 0, (int)reg >> 3);
    Write8(byte1);
    Write8(byte2 + ((int)reg & 7));
}

void XEmitter::CWD(int bits) {
    if (bits == 16)
        Write8(0x66);
    Rex(bits == 64, 0, 0, 0);
    Write8(0x99);
}

void XEmitter::CBW(int bits) {
    if (bits == 8)
        Write8(0x66);
    Rex(bits == 32, 0, 0, 0);
    Write8(0x98);
}

// Simple opcodes

// push/pop do not need wide to be 64-bit
void XEmitter::PUSH(X64Reg reg) {
    WriteSimple1Byte(32, 0x50, reg);
}
void XEmitter::POP(X64Reg reg) {
    WriteSimple1Byte(32, 0x58, reg);
}

void XEmitter::PUSH(int bits, const OpArg& reg) {
    if (reg.IsSimpleReg())
        PUSH(reg.GetSimpleReg());
    else if (reg.IsImm()) {
        switch (reg.GetImmBits()) {
        case 8:
            Write8(0x6A);
            Write8((u8)(s8)reg.offset);
            break;
        case 16:
            Write8(0x66);
            Write8(0x68);
            Write16((u16)(s16)(s32)reg.offset);
            break;
        case 32:
            Write8(0x68);
            Write32((u32)reg.offset);
            break;
        default:
            ASSERT_MSG(0, "PUSH - Bad imm bits");
            break;
        }
    } else {
        if (bits == 16)
            Write8(0x66);
        reg.WriteRex(this, bits, bits);
        Write8(0xFF);
        reg.WriteRest(this, 0, (X64Reg)6);
    }
}

void XEmitter::POP(int /*bits*/, const OpArg& reg) {
    if (reg.IsSimpleReg())
        POP(reg.GetSimpleReg());
    else
        ASSERT_MSG(0, "POP - Unsupported encoding");
}

void XEmitter::BSWAP(int bits, X64Reg reg) {
    if (bits >= 32) {
        WriteSimple2Byte(bits, 0x0F, 0xC8, reg);
    } else if (bits == 16) {
        ROL(16, R(reg), Imm8(8));
    } else if (bits == 8) {
        // Do nothing - can't bswap a single byte...
    } else {
        ASSERT_MSG(0, "BSWAP - Wrong number of bits");
    }
}

// Undefined opcode - reserved
// If we ever need a way to always cause a non-breakpoint hard exception...
void XEmitter::UD2() {
    Write8(0x0F);
    Write8(0x0B);
}

void XEmitter::PREFETCH(PrefetchLevel level, OpArg arg) {
    ASSERT_MSG(!arg.IsImm(), "PREFETCH - Imm argument");
    arg.operandReg = (u8)level;
    arg.WriteRex(this, 0, 0);
    Write8(0x0F);
    Write8(0x18);
    arg.WriteRest(this);
}

void XEmitter::SETcc(CCFlags flag, OpArg dest) {
    ASSERT_MSG(!dest.IsImm(), "SETcc - Imm argument");
    dest.operandReg = 0;
    dest.WriteRex(this, 0, 8);
    Write8(0x0F);
    Write8(0x90 + (u8)flag);
    dest.WriteRest(this);
}

void XEmitter::CMOVcc(int bits, X64Reg dest, OpArg src, CCFlags flag) {
    ASSERT_MSG(!src.IsImm(), "CMOVcc - Imm argument");
    ASSERT_MSG(bits != 8, "CMOVcc - 8 bits unsupported");
    if (bits == 16)
        Write8(0x66);
    src.operandReg = dest;
    src.WriteRex(this, bits, bits);
    Write8(0x0F);
    Write8(0x40 + (u8)flag);
    src.WriteRest(this);
}

void XEmitter::WriteMulDivType(int bits, OpArg src, int ext) {
    ASSERT_MSG(!src.IsImm(), "WriteMulDivType - Imm argument");
    CheckFlags();
    src.operandReg = ext;
    if (bits == 16)
        Write8(0x66);
    src.WriteRex(this, bits, bits, 0);
    if (bits == 8) {
        Write8(0xF6);
    } else {
        Write8(0xF7);
    }
    src.WriteRest(this);
}

void XEmitter::MUL(int bits, const OpArg& src) {
    WriteMulDivType(bits, src, 4);
}
void XEmitter::DIV(int bits, const OpArg& src) {
    WriteMulDivType(bits, src, 6);
}
void XEmitter::IMUL(int bits, const OpArg& src) {
    WriteMulDivType(bits, src, 5);
}
void XEmitter::IDIV(int bits, const OpArg& src) {
    WriteMulDivType(bits, src, 7);
}
void XEmitter::NEG(int bits, const OpArg& src) {
    WriteMulDivType(bits, src, 3);
}
void XEmitter::NOT(int bits, const OpArg& src) {
    WriteMulDivType(bits, src, 2);
}

void XEmitter::WriteBitSearchType(int bits, X64Reg dest, OpArg src, u8 byte2, bool rep) {
    ASSERT_MSG(!src.IsImm(), "WriteBitSearchType - Imm argument");
    CheckFlags();
    src.operandReg = (u8)dest;
    if (bits == 16)
        Write8(0x66);
    if (rep)
        Write8(0xF3);
    src.WriteRex(this, bits, bits);
    Write8(0x0F);
    Write8(byte2);
    src.WriteRest(this);
}

void XEmitter::MOVNTI(int bits, const OpArg& dest, X64Reg src) {
    if (bits <= 16)
        ASSERT_MSG(0, "MOVNTI - bits<=16");
    WriteBitSearchType(bits, src, dest, 0xC3);
}

void XEmitter::BSF(int bits, X64Reg dest, const OpArg& src) {
    WriteBitSearchType(bits, dest, src, 0xBC);
} // Bottom bit to top bit
void XEmitter::BSR(int bits, X64Reg dest, const OpArg& src) {
    WriteBitSearchType(bits, dest, src, 0xBD);
} // Top bit to bottom bit

void XEmitter::TZCNT(int bits, X64Reg dest, const OpArg& src) {
    CheckFlags();
    if (!Common::GetCPUCaps().bmi1)
        ASSERT_MSG(0, "Trying to use BMI1 on a system that doesn't support it. Bad programmer.");
    WriteBitSearchType(bits, dest, src, 0xBC, true);
}
void XEmitter::LZCNT(int bits, X64Reg dest, const OpArg& src) {
    CheckFlags();
    if (!Common::GetCPUCaps().lzcnt)
        ASSERT_MSG(0, "Trying to use LZCNT on a system that doesn't support it. Bad programmer.");
    WriteBitSearchType(bits, dest, src, 0xBD, true);
}

void XEmitter::MOVSX(int dbits, int sbits, X64Reg dest, OpArg src) {
    ASSERT_MSG(!src.IsImm(), "MOVSX - Imm argument");
    if (dbits == sbits) {
        MOV(dbits, R(dest), src);
        return;
    }
    src.operandReg = (u8)dest;
    if (dbits == 16)
        Write8(0x66);
    src.WriteRex(this, dbits, sbits);
    if (sbits == 8) {
        Write8(0x0F);
        Write8(0xBE);
    } else if (sbits == 16) {
        Write8(0x0F);
        Write8(0xBF);
    } else if (sbits == 32 && dbits == 64) {
        Write8(0x63);
    } else {
        Crash();
    }
    src.WriteRest(this);
}

void XEmitter::MOVZX(int dbits, int sbits, X64Reg dest, OpArg src) {
    ASSERT_MSG(!src.IsImm(), "MOVZX - Imm argument");
    if (dbits == sbits) {
        MOV(dbits, R(dest), src);
        return;
    }
    src.operandReg = (u8)dest;
    if (dbits == 16)
        Write8(0x66);
    // the 32bit result is automatically zero extended to 64bit
    src.WriteRex(this, dbits == 64 ? 32 : dbits, sbits);
    if (sbits == 8) {
        Write8(0x0F);
        Write8(0xB6);
    } else if (sbits == 16) {
        Write8(0x0F);
        Write8(0xB7);
    } else if (sbits == 32 && dbits == 64) {
        Write8(0x8B);
    } else {
        ASSERT_MSG(0, "MOVZX - Invalid size");
    }
    src.WriteRest(this);
}

void XEmitter::MOVBE(int bits, const OpArg& dest, const OpArg& src) {
    ASSERT_MSG(Common::GetCPUCaps().movbe,
               "Generating MOVBE on a system that does not support it.");
    if (bits == 8) {
        MOV(bits, dest, src);
        return;
    }

    if (bits == 16)
        Write8(0x66);

    if (dest.IsSimpleReg()) {
        ASSERT_MSG(!src.IsSimpleReg() && !src.IsImm(), "MOVBE: Loading from !mem");
        src.WriteRex(this, bits, bits, dest.GetSimpleReg());
        Write8(0x0F);
        Write8(0x38);
        Write8(0xF0);
        src.WriteRest(this, 0, dest.GetSimpleReg());
    } else if (src.IsSimpleReg()) {
        ASSERT_MSG(!dest.IsSimpleReg() && !dest.IsImm(), "MOVBE: Storing to !mem");
        dest.WriteRex(this, bits, bits, src.GetSimpleReg());
        Write8(0x0F);
        Write8(0x38);
        Write8(0xF1);
        dest.WriteRest(this, 0, src.GetSimpleReg());
    } else {
        ASSERT_MSG(0, "MOVBE: Not loading or storing to mem");
    }
}

void XEmitter::LEA(int bits, X64Reg dest, OpArg src) {
    ASSERT_MSG(!src.IsImm(), "LEA - Imm argument");
    src.operandReg = (u8)dest;
    if (bits == 16)
        Write8(0x66); // TODO: performance warning
    src.WriteRex(this, bits, bits);
    Write8(0x8D);
    src.WriteRest(this, 0, INVALID_REG, bits == 64);
}

// shift can be either imm8 or cl
void XEmitter::WriteShift(int bits, OpArg dest, const OpArg& shift, int ext) {
    CheckFlags();
    bool writeImm = false;
    if (dest.IsImm()) {
        ASSERT_MSG(0, "WriteShift - can't shift imms");
    }
    if ((shift.IsSimpleReg() && shift.GetSimpleReg() != ECX) ||
        (shift.IsImm() && shift.GetImmBits() != 8)) {
        ASSERT_MSG(0, "WriteShift - illegal argument");
    }
    dest.operandReg = ext;
    if (bits == 16)
        Write8(0x66);
    dest.WriteRex(this, bits, bits, 0);
    if (shift.GetImmBits() == 8) {
        // ok an imm
        u8 imm = (u8)shift.offset;
        if (imm == 1) {
            Write8(bits == 8 ? 0xD0 : 0xD1);
        } else {
            writeImm = true;
            Write8(bits == 8 ? 0xC0 : 0xC1);
        }
    } else {
        Write8(bits == 8 ? 0xD2 : 0xD3);
    }
    dest.WriteRest(this, writeImm ? 1 : 0);
    if (writeImm)
        Write8((u8)shift.offset);
}

// large rotates and shift are slower on intel than amd
// intel likes to rotate by 1, and the op is smaller too
void XEmitter::ROL(int bits, const OpArg& dest, const OpArg& shift) {
    WriteShift(bits, dest, shift, 0);
}
void XEmitter::ROR(int bits, const OpArg& dest, const OpArg& shift) {
    WriteShift(bits, dest, shift, 1);
}
void XEmitter::RCL(int bits, const OpArg& dest, const OpArg& shift) {
    WriteShift(bits, dest, shift, 2);
}
void XEmitter::RCR(int bits, const OpArg& dest, const OpArg& shift) {
    WriteShift(bits, dest, shift, 3);
}
void XEmitter::SHL(int bits, const OpArg& dest, const OpArg& shift) {
    WriteShift(bits, dest, shift, 4);
}
void XEmitter::SHR(int bits, const OpArg& dest, const OpArg& shift) {
    WriteShift(bits, dest, shift, 5);
}
void XEmitter::SAR(int bits, const OpArg& dest, const OpArg& shift) {
    WriteShift(bits, dest, shift, 7);
}

// index can be either imm8 or register, don't use memory destination because it's slow
void XEmitter::WriteBitTest(int bits, const OpArg& dest, const OpArg& index, int ext) {
    CheckFlags();
    if (dest.IsImm()) {
        ASSERT_MSG(0, "WriteBitTest - can't test imms");
    }
    if ((index.IsImm() && index.GetImmBits() != 8)) {
        ASSERT_MSG(0, "WriteBitTest - illegal argument");
    }
    if (bits == 16)
        Write8(0x66);
    if (index.IsImm()) {
        dest.WriteRex(this, bits, bits);
        Write8(0x0F);
        Write8(0xBA);
        dest.WriteRest(this, 1, (X64Reg)ext);
        Write8((u8)index.offset);
    } else {
        X64Reg operand = index.GetSimpleReg();
        dest.WriteRex(this, bits, bits, operand);
        Write8(0x0F);
        Write8(0x83 + 8 * ext);
        dest.WriteRest(this, 1, operand);
    }
}

void XEmitter::BT(int bits, const OpArg& dest, const OpArg& index) {
    WriteBitTest(bits, dest, index, 4);
}
void XEmitter::BTS(int bits, const OpArg& dest, const OpArg& index) {
    WriteBitTest(bits, dest, index, 5);
}
void XEmitter::BTR(int bits, const OpArg& dest, const OpArg& index) {
    WriteBitTest(bits, dest, index, 6);
}
void XEmitter::BTC(int bits, const OpArg& dest, const OpArg& index) {
    WriteBitTest(bits, dest, index, 7);
}

// shift can be either imm8 or cl
void XEmitter::SHRD(int bits, const OpArg& dest, const OpArg& src, const OpArg& shift) {
    CheckFlags();
    if (dest.IsImm()) {
        ASSERT_MSG(0, "SHRD - can't use imms as destination");
    }
    if (!src.IsSimpleReg()) {
        ASSERT_MSG(0, "SHRD - must use simple register as source");
    }
    if ((shift.IsSimpleReg() && shift.GetSimpleReg() != ECX) ||
        (shift.IsImm() && shift.GetImmBits() != 8)) {
        ASSERT_MSG(0, "SHRD - illegal shift");
    }
    if (bits == 16)
        Write8(0x66);
    X64Reg operand = src.GetSimpleReg();
    dest.WriteRex(this, bits, bits, operand);
    if (shift.GetImmBits() == 8) {
        Write8(0x0F);
        Write8(0xAC);
        dest.WriteRest(this, 1, operand);
        Write8((u8)shift.offset);
    } else {
        Write8(0x0F);
        Write8(0xAD);
        dest.WriteRest(this, 0, operand);
    }
}

void XEmitter::SHLD(int bits, const OpArg& dest, const OpArg& src, const OpArg& shift) {
    CheckFlags();
    if (dest.IsImm()) {
        ASSERT_MSG(0, "SHLD - can't use imms as destination");
    }
    if (!src.IsSimpleReg()) {
        ASSERT_MSG(0, "SHLD - must use simple register as source");
    }
    if ((shift.IsSimpleReg() && shift.GetSimpleReg() != ECX) ||
        (shift.IsImm() && shift.GetImmBits() != 8)) {
        ASSERT_MSG(0, "SHLD - illegal shift");
    }
    if (bits == 16)
        Write8(0x66);
    X64Reg operand = src.GetSimpleReg();
    dest.WriteRex(this, bits, bits, operand);
    if (shift.GetImmBits() == 8) {
        Write8(0x0F);
        Write8(0xA4);
        dest.WriteRest(this, 1, operand);
        Write8((u8)shift.offset);
    } else {
        Write8(0x0F);
        Write8(0xA5);
        dest.WriteRest(this, 0, operand);
    }
}

void OpArg::WriteSingleByteOp(XEmitter* emit, u8 op, X64Reg _operandReg, int bits) {
    if (bits == 16)
        emit->Write8(0x66);

    this->operandReg = (u8)_operandReg;
    WriteRex(emit, bits, bits);
    emit->Write8(op);
    WriteRest(emit);
}

// operand can either be immediate or register
void OpArg::WriteNormalOp(XEmitter* emit, bool toRM, NormalOp op, const OpArg& operand,
                          int bits) const {
    X64Reg _operandReg;
    if (IsImm()) {
        ASSERT_MSG(0, "WriteNormalOp - Imm argument, wrong order");
    }

    if (bits == 16)
        emit->Write8(0x66);

    int immToWrite = 0;

    if (operand.IsImm()) {
        WriteRex(emit, bits, bits);

        if (!toRM) {
            ASSERT_MSG(0, "WriteNormalOp - Writing to Imm (!toRM)");
        }

        if (operand.scale == SCALE_IMM8 && bits == 8) {
            // op al, imm8
            if (!scale && offsetOrBaseReg == AL && normalops[op].eaximm8 != 0xCC) {
                emit->Write8(normalops[op].eaximm8);
                emit->Write8((u8)operand.offset);
                return;
            }
            // mov reg, imm8
            if (!scale && op == nrmMOV) {
                emit->Write8(0xB0 + (offsetOrBaseReg & 7));
                emit->Write8((u8)operand.offset);
                return;
            }
            // op r/m8, imm8
            emit->Write8(normalops[op].imm8);
            immToWrite = 8;
        } else if ((operand.scale == SCALE_IMM16 && bits == 16) ||
                   (operand.scale == SCALE_IMM32 && bits == 32) ||
                   (operand.scale == SCALE_IMM32 && bits == 64)) {
            // Try to save immediate size if we can, but first check to see
            // if the instruction supports simm8.
            // op r/m, imm8
            if (normalops[op].simm8 != 0xCC &&
                ((operand.scale == SCALE_IMM16 && (s16)operand.offset == (s8)operand.offset) ||
                 (operand.scale == SCALE_IMM32 && (s32)operand.offset == (s8)operand.offset))) {
                emit->Write8(normalops[op].simm8);
                immToWrite = 8;
            } else {
                // mov reg, imm
                if (!scale && op == nrmMOV && bits != 64) {
                    emit->Write8(0xB8 + (offsetOrBaseReg & 7));
                    if (bits == 16)
                        emit->Write16((u16)operand.offset);
                    else
                        emit->Write32((u32)operand.offset);
                    return;
                }
                // op eax, imm
                if (!scale && offsetOrBaseReg == EAX && normalops[op].eaximm32 != 0xCC) {
                    emit->Write8(normalops[op].eaximm32);
                    if (bits == 16)
                        emit->Write16((u16)operand.offset);
                    else
                        emit->Write32((u32)operand.offset);
                    return;
                }
                // op r/m, imm
                emit->Write8(normalops[op].imm32);
                immToWrite = bits == 16 ? 16 : 32;
            }
        } else if ((operand.scale == SCALE_IMM8 && bits == 16) ||
                   (operand.scale == SCALE_IMM8 && bits == 32) ||
                   (operand.scale == SCALE_IMM8 && bits == 64)) {
            // op r/m, imm8
            emit->Write8(normalops[op].simm8);
            immToWrite = 8;
        } else if (operand.scale == SCALE_IMM64 && bits == 64) {
            if (scale) {
                ASSERT_MSG(0, "WriteNormalOp - MOV with 64-bit imm requres register destination");
            }
            // mov reg64, imm64
            else if (op == nrmMOV) {
                emit->Write8(0xB8 + (offsetOrBaseReg & 7));
                emit->Write64((u64)operand.offset);
                return;
            }
            ASSERT_MSG(0, "WriteNormalOp - Only MOV can take 64-bit imm");
        } else {
            ASSERT_MSG(0, "WriteNormalOp - Unhandled case");
        }
        _operandReg = (X64Reg)normalops[op].ext; // pass extension in REG of ModRM
    } else {
        _operandReg = (X64Reg)operand.offsetOrBaseReg;
        WriteRex(emit, bits, bits, _operandReg);
        // op r/m, reg
        if (toRM) {
            emit->Write8(bits == 8 ? normalops[op].toRm8 : normalops[op].toRm32);
        }
        // op reg, r/m
        else {
            emit->Write8(bits == 8 ? normalops[op].fromRm8 : normalops[op].fromRm32);
        }
    }
    WriteRest(emit, immToWrite >> 3, _operandReg);
    switch (immToWrite) {
    case 0:
        break;
    case 8:
        emit->Write8((u8)operand.offset);
        break;
    case 16:
        emit->Write16((u16)operand.offset);
        break;
    case 32:
        emit->Write32((u32)operand.offset);
        break;
    default:
        ASSERT_MSG(0, "WriteNormalOp - Unhandled case");
    }
}

void XEmitter::WriteNormalOp(XEmitter* emit, int bits, NormalOp op, const OpArg& a1,
                             const OpArg& a2) {
    if (a1.IsImm()) {
        // Booh! Can't write to an imm
        ASSERT_MSG(0, "WriteNormalOp - a1 cannot be imm");
        return;
    }
    if (a2.IsImm()) {
        a1.WriteNormalOp(emit, true, op, a2, bits);
    } else {
        if (a1.IsSimpleReg()) {
            a2.WriteNormalOp(emit, false, op, a1, bits);
        } else {
            ASSERT_MSG(a2.IsSimpleReg() || a2.IsImm(),
                       "WriteNormalOp - a1 and a2 cannot both be memory");
            a1.WriteNormalOp(emit, true, op, a2, bits);
        }
    }
}

void XEmitter::ADD(int bits, const OpArg& a1, const OpArg& a2) {
    CheckFlags();
    WriteNormalOp(this, bits, nrmADD, a1, a2);
}
void XEmitter::ADC(int bits, const OpArg& a1, const OpArg& a2) {
    CheckFlags();
    WriteNormalOp(this, bits, nrmADC, a1, a2);
}
void XEmitter::SUB(int bits, const OpArg& a1, const OpArg& a2) {
    CheckFlags();
    WriteNormalOp(this, bits, nrmSUB, a1, a2);
}
void XEmitter::SBB(int bits, const OpArg& a1, const OpArg& a2) {
    CheckFlags();
    WriteNormalOp(this, bits, nrmSBB, a1, a2);
}
void XEmitter::AND(int bits, const OpArg& a1, const OpArg& a2) {
    CheckFlags();
    WriteNormalOp(this, bits, nrmAND, a1, a2);
}
void XEmitter::OR(int bits, const OpArg& a1, const OpArg& a2) {
    CheckFlags();
    WriteNormalOp(this, bits, nrmOR, a1, a2);
}
void XEmitter::XOR(int bits, const OpArg& a1, const OpArg& a2) {
    CheckFlags();
    WriteNormalOp(this, bits, nrmXOR, a1, a2);
}
void XEmitter::MOV(int bits, const OpArg& a1, const OpArg& a2) {
    if (a1.IsSimpleReg() && a2.IsSimpleReg() && a1.GetSimpleReg() == a2.GetSimpleReg())
        LOG_ERROR(Common, "Redundant MOV @ %p - bug in JIT?", code);
    WriteNormalOp(this, bits, nrmMOV, a1, a2);
}
void XEmitter::TEST(int bits, const OpArg& a1, const OpArg& a2) {
    CheckFlags();
    WriteNormalOp(this, bits, nrmTEST, a1, a2);
}
void XEmitter::CMP(int bits, const OpArg& a1, const OpArg& a2) {
    CheckFlags();
    WriteNormalOp(this, bits, nrmCMP, a1, a2);
}
void XEmitter::XCHG(int bits, const OpArg& a1, const OpArg& a2) {
    WriteNormalOp(this, bits, nrmXCHG, a1, a2);
}

void XEmitter::IMUL(int bits, X64Reg regOp, const OpArg& a1, const OpArg& a2) {
    CheckFlags();
    if (bits == 8) {
        ASSERT_MSG(0, "IMUL - illegal bit size!");
        return;
    }

    if (a1.IsImm()) {
        ASSERT_MSG(0, "IMUL - second arg cannot be imm!");
        return;
    }

    if (!a2.IsImm()) {
        ASSERT_MSG(0, "IMUL - third arg must be imm!");
        return;
    }

    if (bits == 16)
        Write8(0x66);
    a1.WriteRex(this, bits, bits, regOp);

    if (a2.GetImmBits() == 8 || (a2.GetImmBits() == 16 && (s8)a2.offset == (s16)a2.offset) ||
        (a2.GetImmBits() == 32 && (s8)a2.offset == (s32)a2.offset)) {
        Write8(0x6B);
        a1.WriteRest(this, 1, regOp);
        Write8((u8)a2.offset);
    } else {
        Write8(0x69);
        if (a2.GetImmBits() == 16 && bits == 16) {
            a1.WriteRest(this, 2, regOp);
            Write16((u16)a2.offset);
        } else if (a2.GetImmBits() == 32 && (bits == 32 || bits == 64)) {
            a1.WriteRest(this, 4, regOp);
            Write32((u32)a2.offset);
        } else {
            ASSERT_MSG(0, "IMUL - unhandled case!");
        }
    }
}

void XEmitter::IMUL(int bits, X64Reg regOp, const OpArg& a) {
    CheckFlags();
    if (bits == 8) {
        ASSERT_MSG(0, "IMUL - illegal bit size!");
        return;
    }

    if (a.IsImm()) {
        IMUL(bits, regOp, R(regOp), a);
        return;
    }

    if (bits == 16)
        Write8(0x66);
    a.WriteRex(this, bits, bits, regOp);
    Write8(0x0F);
    Write8(0xAF);
    a.WriteRest(this, 0, regOp);
}

void XEmitter::WriteSSEOp(u8 opPrefix, u16 op, X64Reg regOp, OpArg arg, int extrabytes) {
    if (opPrefix)
        Write8(opPrefix);
    arg.operandReg = regOp;
    arg.WriteRex(this, 0, 0);
    Write8(0x0F);
    if (op > 0xFF)
        Write8((op >> 8) & 0xFF);
    Write8(op & 0xFF);
    arg.WriteRest(this, extrabytes);
}

void XEmitter::WriteAVXOp(u8 opPrefix, u16 op, X64Reg regOp, const OpArg& arg, int extrabytes) {
    WriteAVXOp(opPrefix, op, regOp, INVALID_REG, arg, extrabytes);
}

static int GetVEXmmmmm(u16 op) {
    // Currently, only 0x38 and 0x3A are used as secondary escape byte.
    if ((op >> 8) == 0x3A)
        return 3;
    if ((op >> 8) == 0x38)
        return 2;

    return 1;
}

static int GetVEXpp(u8 opPrefix) {
    if (opPrefix == 0x66)
        return 1;
    if (opPrefix == 0xF3)
        return 2;
    if (opPrefix == 0xF2)
        return 3;

    return 0;
}

void XEmitter::WriteAVXOp(u8 opPrefix, u16 op, X64Reg regOp1, X64Reg regOp2, const OpArg& arg,
                          int extrabytes) {
    if (!Common::GetCPUCaps().avx)
        ASSERT_MSG(0, "Trying to use AVX on a system that doesn't support it. Bad programmer.");
    int mmmmm = GetVEXmmmmm(op);
    int pp = GetVEXpp(opPrefix);
    // FIXME: we currently don't support 256-bit instructions, and "size" is not the vector size
    // here
    arg.WriteVex(this, regOp1, regOp2, 0, pp, mmmmm);
    Write8(op & 0xFF);
    arg.WriteRest(this, extrabytes, regOp1);
}

// Like the above, but more general; covers GPR-based VEX operations, like BMI1/2
void XEmitter::WriteVEXOp(int size, u8 opPrefix, u16 op, X64Reg regOp1, X64Reg regOp2,
                          const OpArg& arg, int extrabytes) {
    if (size != 32 && size != 64)
        ASSERT_MSG(0, "VEX GPR instructions only support 32-bit and 64-bit modes!");
    int mmmmm = GetVEXmmmmm(op);
    int pp = GetVEXpp(opPrefix);
    arg.WriteVex(this, regOp1, regOp2, 0, pp, mmmmm, size == 64);
    Write8(op & 0xFF);
    arg.WriteRest(this, extrabytes, regOp1);
}

void XEmitter::WriteBMI1Op(int size, u8 opPrefix, u16 op, X64Reg regOp1, X64Reg regOp2,
                           const OpArg& arg, int extrabytes) {
    CheckFlags();
    if (!Common::GetCPUCaps().bmi1)
        ASSERT_MSG(0, "Trying to use BMI1 on a system that doesn't support it. Bad programmer.");
    WriteVEXOp(size, opPrefix, op, regOp1, regOp2, arg, extrabytes);
}

void XEmitter::WriteBMI2Op(int size, u8 opPrefix, u16 op, X64Reg regOp1, X64Reg regOp2,
                           const OpArg& arg, int extrabytes) {
    CheckFlags();
    if (!Common::GetCPUCaps().bmi2)
        ASSERT_MSG(0, "Trying to use BMI2 on a system that doesn't support it. Bad programmer.");
    WriteVEXOp(size, opPrefix, op, regOp1, regOp2, arg, extrabytes);
}

void XEmitter::MOVD_xmm(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x6E, dest, arg, 0);
}
void XEmitter::MOVD_xmm(const OpArg& arg, X64Reg src) {
    WriteSSEOp(0x66, 0x7E, src, arg, 0);
}

void XEmitter::MOVQ_xmm(X64Reg dest, OpArg arg) {
#ifdef ARCHITECTURE_x86_64
    // Alternate encoding
    // This does not display correctly in MSVC's debugger, it thinks it's a MOVD
    arg.operandReg = dest;
    Write8(0x66);
    arg.WriteRex(this, 64, 0);
    Write8(0x0f);
    Write8(0x6E);
    arg.WriteRest(this, 0);
#else
    arg.operandReg = dest;
    Write8(0xF3);
    Write8(0x0f);
    Write8(0x7E);
    arg.WriteRest(this, 0);
#endif
}

void XEmitter::MOVQ_xmm(OpArg arg, X64Reg src) {
    if (src > 7 || arg.IsSimpleReg()) {
        // Alternate encoding
        // This does not display correctly in MSVC's debugger, it thinks it's a MOVD
        arg.operandReg = src;
        Write8(0x66);
        arg.WriteRex(this, 64, 0);
        Write8(0x0f);
        Write8(0x7E);
        arg.WriteRest(this, 0);
    } else {
        arg.operandReg = src;
        arg.WriteRex(this, 0, 0);
        Write8(0x66);
        Write8(0x0f);
        Write8(0xD6);
        arg.WriteRest(this, 0);
    }
}

void XEmitter::WriteMXCSR(OpArg arg, int ext) {
    if (arg.IsImm() || arg.IsSimpleReg())
        ASSERT_MSG(0, "MXCSR - invalid operand");

    arg.operandReg = ext;
    arg.WriteRex(this, 0, 0);
    Write8(0x0F);
    Write8(0xAE);
    arg.WriteRest(this);
}

void XEmitter::STMXCSR(const OpArg& memloc) {
    WriteMXCSR(memloc, 3);
}
void XEmitter::LDMXCSR(const OpArg& memloc) {
    WriteMXCSR(memloc, 2);
}

void XEmitter::MOVNTDQ(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0x66, sseMOVNTDQ, regOp, arg);
}
void XEmitter::MOVNTPS(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0x00, sseMOVNTP, regOp, arg);
}
void XEmitter::MOVNTPD(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0x66, sseMOVNTP, regOp, arg);
}

void XEmitter::ADDSS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, sseADD, regOp, arg);
}
void XEmitter::ADDSD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF2, sseADD, regOp, arg);
}
void XEmitter::SUBSS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, sseSUB, regOp, arg);
}
void XEmitter::SUBSD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF2, sseSUB, regOp, arg);
}
void XEmitter::CMPSS(X64Reg regOp, const OpArg& arg, u8 compare) {
    WriteSSEOp(0xF3, sseCMP, regOp, arg, 1);
    Write8(compare);
}
void XEmitter::CMPSD(X64Reg regOp, const OpArg& arg, u8 compare) {
    WriteSSEOp(0xF2, sseCMP, regOp, arg, 1);
    Write8(compare);
}
void XEmitter::MULSS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, sseMUL, regOp, arg);
}
void XEmitter::MULSD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF2, sseMUL, regOp, arg);
}
void XEmitter::DIVSS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, sseDIV, regOp, arg);
}
void XEmitter::DIVSD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF2, sseDIV, regOp, arg);
}
void XEmitter::MINSS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, sseMIN, regOp, arg);
}
void XEmitter::MINSD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF2, sseMIN, regOp, arg);
}
void XEmitter::MAXSS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, sseMAX, regOp, arg);
}
void XEmitter::MAXSD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF2, sseMAX, regOp, arg);
}
void XEmitter::SQRTSS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, sseSQRT, regOp, arg);
}
void XEmitter::SQRTSD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF2, sseSQRT, regOp, arg);
}
void XEmitter::RCPSS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, sseRCP, regOp, arg);
}
void XEmitter::RSQRTSS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, sseRSQRT, regOp, arg);
}

void XEmitter::ADDPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseADD, regOp, arg);
}
void XEmitter::ADDPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseADD, regOp, arg);
}
void XEmitter::SUBPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseSUB, regOp, arg);
}
void XEmitter::SUBPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseSUB, regOp, arg);
}
void XEmitter::CMPPS(X64Reg regOp, const OpArg& arg, u8 compare) {
    WriteSSEOp(0x00, sseCMP, regOp, arg, 1);
    Write8(compare);
}
void XEmitter::CMPPD(X64Reg regOp, const OpArg& arg, u8 compare) {
    WriteSSEOp(0x66, sseCMP, regOp, arg, 1);
    Write8(compare);
}
void XEmitter::ANDPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseAND, regOp, arg);
}
void XEmitter::ANDPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseAND, regOp, arg);
}
void XEmitter::ANDNPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseANDN, regOp, arg);
}
void XEmitter::ANDNPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseANDN, regOp, arg);
}
void XEmitter::ORPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseOR, regOp, arg);
}
void XEmitter::ORPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseOR, regOp, arg);
}
void XEmitter::XORPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseXOR, regOp, arg);
}
void XEmitter::XORPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseXOR, regOp, arg);
}
void XEmitter::MULPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseMUL, regOp, arg);
}
void XEmitter::MULPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseMUL, regOp, arg);
}
void XEmitter::DIVPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseDIV, regOp, arg);
}
void XEmitter::DIVPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseDIV, regOp, arg);
}
void XEmitter::MINPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseMIN, regOp, arg);
}
void XEmitter::MINPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseMIN, regOp, arg);
}
void XEmitter::MAXPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseMAX, regOp, arg);
}
void XEmitter::MAXPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseMAX, regOp, arg);
}
void XEmitter::SQRTPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseSQRT, regOp, arg);
}
void XEmitter::SQRTPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseSQRT, regOp, arg);
}
void XEmitter::RCPPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseRCP, regOp, arg);
}
void XEmitter::RSQRTPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseRSQRT, regOp, arg);
}
void XEmitter::SHUFPS(X64Reg regOp, const OpArg& arg, u8 shuffle) {
    WriteSSEOp(0x00, sseSHUF, regOp, arg, 1);
    Write8(shuffle);
}
void XEmitter::SHUFPD(X64Reg regOp, const OpArg& arg, u8 shuffle) {
    WriteSSEOp(0x66, sseSHUF, regOp, arg, 1);
    Write8(shuffle);
}

void XEmitter::HADDPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF2, sseHADD, regOp, arg);
}

void XEmitter::COMISS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseCOMIS, regOp, arg);
} // weird that these should be packed
void XEmitter::COMISD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseCOMIS, regOp, arg);
} // ordered
void XEmitter::UCOMISS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseUCOMIS, regOp, arg);
} // unordered
void XEmitter::UCOMISD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseUCOMIS, regOp, arg);
}

void XEmitter::MOVAPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseMOVAPfromRM, regOp, arg);
}
void XEmitter::MOVAPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseMOVAPfromRM, regOp, arg);
}
void XEmitter::MOVAPS(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0x00, sseMOVAPtoRM, regOp, arg);
}
void XEmitter::MOVAPD(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0x66, sseMOVAPtoRM, regOp, arg);
}

void XEmitter::MOVUPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseMOVUPfromRM, regOp, arg);
}
void XEmitter::MOVUPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseMOVUPfromRM, regOp, arg);
}
void XEmitter::MOVUPS(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0x00, sseMOVUPtoRM, regOp, arg);
}
void XEmitter::MOVUPD(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0x66, sseMOVUPtoRM, regOp, arg);
}

void XEmitter::MOVDQA(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseMOVDQfromRM, regOp, arg);
}
void XEmitter::MOVDQA(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0x66, sseMOVDQtoRM, regOp, arg);
}
void XEmitter::MOVDQU(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, sseMOVDQfromRM, regOp, arg);
}
void XEmitter::MOVDQU(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0xF3, sseMOVDQtoRM, regOp, arg);
}

void XEmitter::MOVSS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, sseMOVUPfromRM, regOp, arg);
}
void XEmitter::MOVSD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF2, sseMOVUPfromRM, regOp, arg);
}
void XEmitter::MOVSS(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0xF3, sseMOVUPtoRM, regOp, arg);
}
void XEmitter::MOVSD(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0xF2, sseMOVUPtoRM, regOp, arg);
}

void XEmitter::MOVLPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseMOVLPfromRM, regOp, arg);
}
void XEmitter::MOVLPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseMOVLPfromRM, regOp, arg);
}
void XEmitter::MOVLPS(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0x00, sseMOVLPtoRM, regOp, arg);
}
void XEmitter::MOVLPD(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0x66, sseMOVLPtoRM, regOp, arg);
}

void XEmitter::MOVHPS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, sseMOVHPfromRM, regOp, arg);
}
void XEmitter::MOVHPD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, sseMOVHPfromRM, regOp, arg);
}
void XEmitter::MOVHPS(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0x00, sseMOVHPtoRM, regOp, arg);
}
void XEmitter::MOVHPD(const OpArg& arg, X64Reg regOp) {
    WriteSSEOp(0x66, sseMOVHPtoRM, regOp, arg);
}

void XEmitter::MOVHLPS(X64Reg regOp1, X64Reg regOp2) {
    WriteSSEOp(0x00, sseMOVHLPS, regOp1, R(regOp2));
}
void XEmitter::MOVLHPS(X64Reg regOp1, X64Reg regOp2) {
    WriteSSEOp(0x00, sseMOVLHPS, regOp1, R(regOp2));
}

void XEmitter::CVTPS2PD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, 0x5A, regOp, arg);
}
void XEmitter::CVTPD2PS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, 0x5A, regOp, arg);
}

void XEmitter::CVTSD2SS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF2, 0x5A, regOp, arg);
}
void XEmitter::CVTSS2SD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, 0x5A, regOp, arg);
}
void XEmitter::CVTSD2SI(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF2, 0x2D, regOp, arg);
}
void XEmitter::CVTSS2SI(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, 0x2D, regOp, arg);
}
void XEmitter::CVTSI2SD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF2, 0x2A, regOp, arg);
}
void XEmitter::CVTSI2SS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, 0x2A, regOp, arg);
}

void XEmitter::CVTDQ2PD(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, 0xE6, regOp, arg);
}
void XEmitter::CVTDQ2PS(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x00, 0x5B, regOp, arg);
}
void XEmitter::CVTPD2DQ(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF2, 0xE6, regOp, arg);
}
void XEmitter::CVTPS2DQ(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, 0x5B, regOp, arg);
}

void XEmitter::CVTTSD2SI(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF2, 0x2C, regOp, arg);
}
void XEmitter::CVTTSS2SI(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, 0x2C, regOp, arg);
}
void XEmitter::CVTTPS2DQ(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0xF3, 0x5B, regOp, arg);
}
void XEmitter::CVTTPD2DQ(X64Reg regOp, const OpArg& arg) {
    WriteSSEOp(0x66, 0xE6, regOp, arg);
}

void XEmitter::MASKMOVDQU(X64Reg dest, X64Reg src) {
    WriteSSEOp(0x66, sseMASKMOVDQU, dest, R(src));
}

void XEmitter::MOVMSKPS(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x00, 0x50, dest, arg);
}
void XEmitter::MOVMSKPD(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x50, dest, arg);
}

void XEmitter::LDDQU(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0xF2, sseLDDQU, dest, arg);
} // For integer data only

// THESE TWO ARE UNTESTED.
void XEmitter::UNPCKLPS(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x00, 0x14, dest, arg);
}
void XEmitter::UNPCKHPS(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x00, 0x15, dest, arg);
}

void XEmitter::UNPCKLPD(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x14, dest, arg);
}
void XEmitter::UNPCKHPD(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x15, dest, arg);
}

void XEmitter::MOVDDUP(X64Reg regOp, const OpArg& arg) {
    if (Common::GetCPUCaps().sse3) {
        WriteSSEOp(0xF2, 0x12, regOp, arg); // SSE3 movddup
    } else {
        // Simulate this instruction with SSE2 instructions
        if (!arg.IsSimpleReg(regOp))
            MOVSD(regOp, arg);
        UNPCKLPD(regOp, R(regOp));
    }
}

// There are a few more left

// Also some integer instructions are missing
void XEmitter::PACKSSDW(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x6B, dest, arg);
}
void XEmitter::PACKSSWB(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x63, dest, arg);
}
void XEmitter::PACKUSWB(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x67, dest, arg);
}

void XEmitter::PUNPCKLBW(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x60, dest, arg);
}
void XEmitter::PUNPCKLWD(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x61, dest, arg);
}
void XEmitter::PUNPCKLDQ(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x62, dest, arg);
}
void XEmitter::PUNPCKLQDQ(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x6C, dest, arg);
}

void XEmitter::PSRLW(X64Reg reg, int shift) {
    WriteSSEOp(0x66, 0x71, (X64Reg)2, R(reg));
    Write8(shift);
}

void XEmitter::PSRLD(X64Reg reg, int shift) {
    WriteSSEOp(0x66, 0x72, (X64Reg)2, R(reg));
    Write8(shift);
}

void XEmitter::PSRLQ(X64Reg reg, int shift) {
    WriteSSEOp(0x66, 0x73, (X64Reg)2, R(reg));
    Write8(shift);
}

void XEmitter::PSRLQ(X64Reg reg, const OpArg& arg) {
    WriteSSEOp(0x66, 0xd3, reg, arg);
}

void XEmitter::PSRLDQ(X64Reg reg, int shift) {
    WriteSSEOp(0x66, 0x73, (X64Reg)3, R(reg));
    Write8(shift);
}

void XEmitter::PSLLW(X64Reg reg, int shift) {
    WriteSSEOp(0x66, 0x71, (X64Reg)6, R(reg));
    Write8(shift);
}

void XEmitter::PSLLD(X64Reg reg, int shift) {
    WriteSSEOp(0x66, 0x72, (X64Reg)6, R(reg));
    Write8(shift);
}

void XEmitter::PSLLQ(X64Reg reg, int shift) {
    WriteSSEOp(0x66, 0x73, (X64Reg)6, R(reg));
    Write8(shift);
}

void XEmitter::PSLLDQ(X64Reg reg, int shift) {
    WriteSSEOp(0x66, 0x73, (X64Reg)7, R(reg));
    Write8(shift);
}

void XEmitter::PSRAW(X64Reg reg, int shift) {
    WriteSSEOp(0x66, 0x71, (X64Reg)4, R(reg));
    Write8(shift);
}

void XEmitter::PSRAD(X64Reg reg, int shift) {
    WriteSSEOp(0x66, 0x72, (X64Reg)4, R(reg));
    Write8(shift);
}

void XEmitter::WriteSSSE3Op(u8 opPrefix, u16 op, X64Reg regOp, const OpArg& arg, int extrabytes) {
    if (!Common::GetCPUCaps().ssse3)
        ASSERT_MSG(0, "Trying to use SSSE3 on a system that doesn't support it. Bad programmer.");
    WriteSSEOp(opPrefix, op, regOp, arg, extrabytes);
}

void XEmitter::WriteSSE41Op(u8 opPrefix, u16 op, X64Reg regOp, const OpArg& arg, int extrabytes) {
    if (!Common::GetCPUCaps().sse4_1)
        ASSERT_MSG(0, "Trying to use SSE4.1 on a system that doesn't support it. Bad programmer.");
    WriteSSEOp(opPrefix, op, regOp, arg, extrabytes);
}

void XEmitter::PSHUFB(X64Reg dest, const OpArg& arg) {
    WriteSSSE3Op(0x66, 0x3800, dest, arg);
}
void XEmitter::PTEST(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3817, dest, arg);
}
void XEmitter::PACKUSDW(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x382b, dest, arg);
}
void XEmitter::DPPS(X64Reg dest, const OpArg& arg, u8 mask) {
    WriteSSE41Op(0x66, 0x3A40, dest, arg, 1);
    Write8(mask);
}

void XEmitter::PMINSB(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3838, dest, arg);
}
void XEmitter::PMINSD(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3839, dest, arg);
}
void XEmitter::PMINUW(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x383a, dest, arg);
}
void XEmitter::PMINUD(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x383b, dest, arg);
}
void XEmitter::PMAXSB(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x383c, dest, arg);
}
void XEmitter::PMAXSD(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x383d, dest, arg);
}
void XEmitter::PMAXUW(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x383e, dest, arg);
}
void XEmitter::PMAXUD(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x383f, dest, arg);
}

void XEmitter::PMOVSXBW(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3820, dest, arg);
}
void XEmitter::PMOVSXBD(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3821, dest, arg);
}
void XEmitter::PMOVSXBQ(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3822, dest, arg);
}
void XEmitter::PMOVSXWD(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3823, dest, arg);
}
void XEmitter::PMOVSXWQ(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3824, dest, arg);
}
void XEmitter::PMOVSXDQ(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3825, dest, arg);
}
void XEmitter::PMOVZXBW(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3830, dest, arg);
}
void XEmitter::PMOVZXBD(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3831, dest, arg);
}
void XEmitter::PMOVZXBQ(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3832, dest, arg);
}
void XEmitter::PMOVZXWD(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3833, dest, arg);
}
void XEmitter::PMOVZXWQ(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3834, dest, arg);
}
void XEmitter::PMOVZXDQ(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3835, dest, arg);
}

void XEmitter::PBLENDVB(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3810, dest, arg);
}
void XEmitter::BLENDVPS(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3814, dest, arg);
}
void XEmitter::BLENDVPD(X64Reg dest, const OpArg& arg) {
    WriteSSE41Op(0x66, 0x3815, dest, arg);
}
void XEmitter::BLENDPS(X64Reg dest, const OpArg& arg, u8 blend) {
    WriteSSE41Op(0x66, 0x3A0C, dest, arg, 1);
    Write8(blend);
}
void XEmitter::BLENDPD(X64Reg dest, const OpArg& arg, u8 blend) {
    WriteSSE41Op(0x66, 0x3A0D, dest, arg, 1);
    Write8(blend);
}

void XEmitter::ROUNDSS(X64Reg dest, const OpArg& arg, u8 mode) {
    WriteSSE41Op(0x66, 0x3A0A, dest, arg, 1);
    Write8(mode);
}
void XEmitter::ROUNDSD(X64Reg dest, const OpArg& arg, u8 mode) {
    WriteSSE41Op(0x66, 0x3A0B, dest, arg, 1);
    Write8(mode);
}
void XEmitter::ROUNDPS(X64Reg dest, const OpArg& arg, u8 mode) {
    WriteSSE41Op(0x66, 0x3A08, dest, arg, 1);
    Write8(mode);
}
void XEmitter::ROUNDPD(X64Reg dest, const OpArg& arg, u8 mode) {
    WriteSSE41Op(0x66, 0x3A09, dest, arg, 1);
    Write8(mode);
}

void XEmitter::PAND(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xDB, dest, arg);
}
void XEmitter::PANDN(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xDF, dest, arg);
}
void XEmitter::PXOR(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xEF, dest, arg);
}
void XEmitter::POR(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xEB, dest, arg);
}

void XEmitter::PADDB(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xFC, dest, arg);
}
void XEmitter::PADDW(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xFD, dest, arg);
}
void XEmitter::PADDD(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xFE, dest, arg);
}
void XEmitter::PADDQ(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xD4, dest, arg);
}

void XEmitter::PADDSB(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xEC, dest, arg);
}
void XEmitter::PADDSW(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xED, dest, arg);
}
void XEmitter::PADDUSB(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xDC, dest, arg);
}
void XEmitter::PADDUSW(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xDD, dest, arg);
}

void XEmitter::PSUBB(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xF8, dest, arg);
}
void XEmitter::PSUBW(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xF9, dest, arg);
}
void XEmitter::PSUBD(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xFA, dest, arg);
}
void XEmitter::PSUBQ(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xFB, dest, arg);
}

void XEmitter::PSUBSB(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xE8, dest, arg);
}
void XEmitter::PSUBSW(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xE9, dest, arg);
}
void XEmitter::PSUBUSB(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xD8, dest, arg);
}
void XEmitter::PSUBUSW(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xD9, dest, arg);
}

void XEmitter::PAVGB(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xE0, dest, arg);
}
void XEmitter::PAVGW(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xE3, dest, arg);
}

void XEmitter::PCMPEQB(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x74, dest, arg);
}
void XEmitter::PCMPEQW(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x75, dest, arg);
}
void XEmitter::PCMPEQD(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x76, dest, arg);
}

void XEmitter::PCMPGTB(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x64, dest, arg);
}
void XEmitter::PCMPGTW(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x65, dest, arg);
}
void XEmitter::PCMPGTD(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0x66, dest, arg);
}

void XEmitter::PEXTRW(X64Reg dest, const OpArg& arg, u8 subreg) {
    WriteSSEOp(0x66, 0xC5, dest, arg, 1);
    Write8(subreg);
}
void XEmitter::PINSRW(X64Reg dest, const OpArg& arg, u8 subreg) {
    WriteSSEOp(0x66, 0xC4, dest, arg, 1);
    Write8(subreg);
}

void XEmitter::PMADDWD(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xF5, dest, arg);
}
void XEmitter::PSADBW(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xF6, dest, arg);
}

void XEmitter::PMAXSW(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xEE, dest, arg);
}
void XEmitter::PMAXUB(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xDE, dest, arg);
}
void XEmitter::PMINSW(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xEA, dest, arg);
}
void XEmitter::PMINUB(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xDA, dest, arg);
}

void XEmitter::PMOVMSKB(X64Reg dest, const OpArg& arg) {
    WriteSSEOp(0x66, 0xD7, dest, arg);
}
void XEmitter::PSHUFD(X64Reg regOp, const OpArg& arg, u8 shuffle) {
    WriteSSEOp(0x66, 0x70, regOp, arg, 1);
    Write8(shuffle);
}
void XEmitter::PSHUFLW(X64Reg regOp, const OpArg& arg, u8 shuffle) {
    WriteSSEOp(0xF2, 0x70, regOp, arg, 1);
    Write8(shuffle);
}
void XEmitter::PSHUFHW(X64Reg regOp, const OpArg& arg, u8 shuffle) {
    WriteSSEOp(0xF3, 0x70, regOp, arg, 1);
    Write8(shuffle);
}

// VEX
void XEmitter::VADDSD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0xF2, sseADD, regOp1, regOp2, arg);
}
void XEmitter::VSUBSD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0xF2, sseSUB, regOp1, regOp2, arg);
}
void XEmitter::VMULSD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0xF2, sseMUL, regOp1, regOp2, arg);
}
void XEmitter::VDIVSD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0xF2, sseDIV, regOp1, regOp2, arg);
}
void XEmitter::VADDPD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, sseADD, regOp1, regOp2, arg);
}
void XEmitter::VSUBPD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, sseSUB, regOp1, regOp2, arg);
}
void XEmitter::VMULPD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, sseMUL, regOp1, regOp2, arg);
}
void XEmitter::VDIVPD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, sseDIV, regOp1, regOp2, arg);
}
void XEmitter::VSQRTSD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0xF2, sseSQRT, regOp1, regOp2, arg);
}
void XEmitter::VSHUFPD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg, u8 shuffle) {
    WriteAVXOp(0x66, sseSHUF, regOp1, regOp2, arg, 1);
    Write8(shuffle);
}
void XEmitter::VUNPCKLPD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x14, regOp1, regOp2, arg);
}
void XEmitter::VUNPCKHPD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x15, regOp1, regOp2, arg);
}

void XEmitter::VANDPS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x00, sseAND, regOp1, regOp2, arg);
}
void XEmitter::VANDPD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, sseAND, regOp1, regOp2, arg);
}
void XEmitter::VANDNPS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x00, sseANDN, regOp1, regOp2, arg);
}
void XEmitter::VANDNPD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, sseANDN, regOp1, regOp2, arg);
}
void XEmitter::VORPS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x00, sseOR, regOp1, regOp2, arg);
}
void XEmitter::VORPD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, sseOR, regOp1, regOp2, arg);
}
void XEmitter::VXORPS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x00, sseXOR, regOp1, regOp2, arg);
}
void XEmitter::VXORPD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, sseXOR, regOp1, regOp2, arg);
}

void XEmitter::VPAND(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0xDB, regOp1, regOp2, arg);
}
void XEmitter::VPANDN(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0xDF, regOp1, regOp2, arg);
}
void XEmitter::VPOR(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0xEB, regOp1, regOp2, arg);
}
void XEmitter::VPXOR(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0xEF, regOp1, regOp2, arg);
}

void XEmitter::VFMADD132PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x3898, regOp1, regOp2, arg);
}
void XEmitter::VFMADD213PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38A8, regOp1, regOp2, arg);
}
void XEmitter::VFMADD231PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38B8, regOp1, regOp2, arg);
}
void XEmitter::VFMADD132PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x3898, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMADD213PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38A8, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMADD231PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38B8, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMADD132SS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x3899, regOp1, regOp2, arg);
}
void XEmitter::VFMADD213SS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38A9, regOp1, regOp2, arg);
}
void XEmitter::VFMADD231SS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38B9, regOp1, regOp2, arg);
}
void XEmitter::VFMADD132SD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x3899, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMADD213SD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38A9, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMADD231SD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38B9, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMSUB132PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x389A, regOp1, regOp2, arg);
}
void XEmitter::VFMSUB213PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38AA, regOp1, regOp2, arg);
}
void XEmitter::VFMSUB231PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38BA, regOp1, regOp2, arg);
}
void XEmitter::VFMSUB132PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x389A, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMSUB213PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38AA, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMSUB231PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38BA, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMSUB132SS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x389B, regOp1, regOp2, arg);
}
void XEmitter::VFMSUB213SS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38AB, regOp1, regOp2, arg);
}
void XEmitter::VFMSUB231SS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38BB, regOp1, regOp2, arg);
}
void XEmitter::VFMSUB132SD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x389B, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMSUB213SD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38AB, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMSUB231SD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38BB, regOp1, regOp2, arg, 1);
}
void XEmitter::VFNMADD132PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x389C, regOp1, regOp2, arg);
}
void XEmitter::VFNMADD213PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38AC, regOp1, regOp2, arg);
}
void XEmitter::VFNMADD231PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38BC, regOp1, regOp2, arg);
}
void XEmitter::VFNMADD132PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x389C, regOp1, regOp2, arg, 1);
}
void XEmitter::VFNMADD213PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38AC, regOp1, regOp2, arg, 1);
}
void XEmitter::VFNMADD231PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38BC, regOp1, regOp2, arg, 1);
}
void XEmitter::VFNMADD132SS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x389D, regOp1, regOp2, arg);
}
void XEmitter::VFNMADD213SS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38AD, regOp1, regOp2, arg);
}
void XEmitter::VFNMADD231SS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38BD, regOp1, regOp2, arg);
}
void XEmitter::VFNMADD132SD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x389D, regOp1, regOp2, arg, 1);
}
void XEmitter::VFNMADD213SD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38AD, regOp1, regOp2, arg, 1);
}
void XEmitter::VFNMADD231SD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38BD, regOp1, regOp2, arg, 1);
}
void XEmitter::VFNMSUB132PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x389E, regOp1, regOp2, arg);
}
void XEmitter::VFNMSUB213PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38AE, regOp1, regOp2, arg);
}
void XEmitter::VFNMSUB231PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38BE, regOp1, regOp2, arg);
}
void XEmitter::VFNMSUB132PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x389E, regOp1, regOp2, arg, 1);
}
void XEmitter::VFNMSUB213PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38AE, regOp1, regOp2, arg, 1);
}
void XEmitter::VFNMSUB231PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38BE, regOp1, regOp2, arg, 1);
}
void XEmitter::VFNMSUB132SS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x389F, regOp1, regOp2, arg);
}
void XEmitter::VFNMSUB213SS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38AF, regOp1, regOp2, arg);
}
void XEmitter::VFNMSUB231SS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38BF, regOp1, regOp2, arg);
}
void XEmitter::VFNMSUB132SD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x389F, regOp1, regOp2, arg, 1);
}
void XEmitter::VFNMSUB213SD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38AF, regOp1, regOp2, arg, 1);
}
void XEmitter::VFNMSUB231SD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38BF, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMADDSUB132PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x3896, regOp1, regOp2, arg);
}
void XEmitter::VFMADDSUB213PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38A6, regOp1, regOp2, arg);
}
void XEmitter::VFMADDSUB231PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38B6, regOp1, regOp2, arg);
}
void XEmitter::VFMADDSUB132PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x3896, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMADDSUB213PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38A6, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMADDSUB231PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38B6, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMSUBADD132PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x3897, regOp1, regOp2, arg);
}
void XEmitter::VFMSUBADD213PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38A7, regOp1, regOp2, arg);
}
void XEmitter::VFMSUBADD231PS(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38B7, regOp1, regOp2, arg);
}
void XEmitter::VFMSUBADD132PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x3897, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMSUBADD213PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38A7, regOp1, regOp2, arg, 1);
}
void XEmitter::VFMSUBADD231PD(X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteAVXOp(0x66, 0x38B7, regOp1, regOp2, arg, 1);
}

void XEmitter::SARX(int bits, X64Reg regOp1, const OpArg& arg, X64Reg regOp2) {
    WriteBMI2Op(bits, 0xF3, 0x38F7, regOp1, regOp2, arg);
}
void XEmitter::SHLX(int bits, X64Reg regOp1, const OpArg& arg, X64Reg regOp2) {
    WriteBMI2Op(bits, 0x66, 0x38F7, regOp1, regOp2, arg);
}
void XEmitter::SHRX(int bits, X64Reg regOp1, const OpArg& arg, X64Reg regOp2) {
    WriteBMI2Op(bits, 0xF2, 0x38F7, regOp1, regOp2, arg);
}
void XEmitter::RORX(int bits, X64Reg regOp, const OpArg& arg, u8 rotate) {
    WriteBMI2Op(bits, 0xF2, 0x3AF0, regOp, INVALID_REG, arg, 1);
    Write8(rotate);
}
void XEmitter::PEXT(int bits, X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteBMI2Op(bits, 0xF3, 0x38F5, regOp1, regOp2, arg);
}
void XEmitter::PDEP(int bits, X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteBMI2Op(bits, 0xF2, 0x38F5, regOp1, regOp2, arg);
}
void XEmitter::MULX(int bits, X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteBMI2Op(bits, 0xF2, 0x38F6, regOp2, regOp1, arg);
}
void XEmitter::BZHI(int bits, X64Reg regOp1, const OpArg& arg, X64Reg regOp2) {
    WriteBMI2Op(bits, 0x00, 0x38F5, regOp1, regOp2, arg);
}
void XEmitter::BLSR(int bits, X64Reg regOp, const OpArg& arg) {
    WriteBMI1Op(bits, 0x00, 0x38F3, (X64Reg)0x1, regOp, arg);
}
void XEmitter::BLSMSK(int bits, X64Reg regOp, const OpArg& arg) {
    WriteBMI1Op(bits, 0x00, 0x38F3, (X64Reg)0x2, regOp, arg);
}
void XEmitter::BLSI(int bits, X64Reg regOp, const OpArg& arg) {
    WriteBMI1Op(bits, 0x00, 0x38F3, (X64Reg)0x3, regOp, arg);
}
void XEmitter::BEXTR(int bits, X64Reg regOp1, const OpArg& arg, X64Reg regOp2) {
    WriteBMI1Op(bits, 0x00, 0x38F7, regOp1, regOp2, arg);
}
void XEmitter::ANDN(int bits, X64Reg regOp1, X64Reg regOp2, const OpArg& arg) {
    WriteBMI1Op(bits, 0x00, 0x38F2, regOp1, regOp2, arg);
}

// Prefixes

void XEmitter::LOCK() {
    Write8(0xF0);
}
void XEmitter::REP() {
    Write8(0xF3);
}
void XEmitter::REPNE() {
    Write8(0xF2);
}
void XEmitter::FSOverride() {
    Write8(0x64);
}
void XEmitter::GSOverride() {
    Write8(0x65);
}

void XEmitter::FWAIT() {
    Write8(0x9B);
}

// TODO: make this more generic
void XEmitter::WriteFloatLoadStore(int bits, FloatOp op, FloatOp op_80b, const OpArg& arg) {
    int mf = 0;
    ASSERT_MSG(!(bits == 80 && op_80b == floatINVALID),
               "WriteFloatLoadStore: 80 bits not supported for this instruction");
    switch (bits) {
    case 32:
        mf = 0;
        break;
    case 64:
        mf = 4;
        break;
    case 80:
        mf = 2;
        break;
    default:
        ASSERT_MSG(0, "WriteFloatLoadStore: invalid bits (should be 32/64/80)");
    }
    Write8(0xd9 | mf);
    // x87 instructions use the reg field of the ModR/M byte as opcode:
    if (bits == 80)
        op = op_80b;
    arg.WriteRest(this, 0, (X64Reg)op);
}

void XEmitter::FLD(int bits, const OpArg& src) {
    WriteFloatLoadStore(bits, floatLD, floatLD80, src);
}
void XEmitter::FST(int bits, const OpArg& dest) {
    WriteFloatLoadStore(bits, floatST, floatINVALID, dest);
}
void XEmitter::FSTP(int bits, const OpArg& dest) {
    WriteFloatLoadStore(bits, floatSTP, floatSTP80, dest);
}
void XEmitter::FNSTSW_AX() {
    Write8(0xDF);
    Write8(0xE0);
}

void XEmitter::RDTSC() {
    Write8(0x0F);
    Write8(0x31);
}

void XCodeBlock::PoisonMemory() {
    // x86/64: 0xCC = breakpoint
    memset(region, 0xCC, region_size);
}
}