/*
 * Copyright (c) 2009, 2016, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package org.graalvm.compiler.asm.amd64;

import static org.graalvm.compiler.asm.NumUtil.isByte;
import static org.graalvm.compiler.asm.NumUtil.isInt;
import static org.graalvm.compiler.asm.NumUtil.isShiftCount;
import static org.graalvm.compiler.asm.NumUtil.isUByte;
import static org.graalvm.compiler.asm.amd64.AMD64AsmOptions.UseAddressNop;
import static org.graalvm.compiler.asm.amd64.AMD64AsmOptions.UseNormalNop;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.AMD64BinaryArithmetic.ADD;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.AMD64BinaryArithmetic.AND;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.AMD64BinaryArithmetic.CMP;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.AMD64BinaryArithmetic.OR;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.AMD64BinaryArithmetic.SBB;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.AMD64BinaryArithmetic.SUB;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.AMD64BinaryArithmetic.XOR;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.AMD64MOp.DEC;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.AMD64MOp.INC;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.AMD64MOp.NEG;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.AMD64MOp.NOT;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.OperandSize.BYTE;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.OperandSize.DWORD;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.OperandSize.PD;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.OperandSize.PS;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.OperandSize.QWORD;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.OperandSize.SD;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.OperandSize.SS;
import static org.graalvm.compiler.asm.amd64.AMD64Assembler.OperandSize.WORD;
import static jdk.vm.ci.amd64.AMD64.CPU;
import static jdk.vm.ci.amd64.AMD64.XMM;
import static jdk.vm.ci.amd64.AMD64.r12;
import static jdk.vm.ci.amd64.AMD64.r13;
import static jdk.vm.ci.amd64.AMD64.rbp;
import static jdk.vm.ci.amd64.AMD64.rip;
import static jdk.vm.ci.amd64.AMD64.rsp;
import static jdk.vm.ci.code.MemoryBarriers.STORE_LOAD;

import org.graalvm.compiler.asm.Assembler;
import org.graalvm.compiler.asm.Label;
import org.graalvm.compiler.asm.NumUtil;
import org.graalvm.compiler.asm.amd64.AMD64Address.Scale;

import jdk.vm.ci.amd64.AMD64;
import jdk.vm.ci.amd64.AMD64.CPUFeature;
import jdk.vm.ci.code.Register;
import jdk.vm.ci.code.Register.RegisterCategory;
import jdk.vm.ci.code.TargetDescription;

This class implements an assembler that can encode most X86 instructions.
/**
 * This class implements an assembler that can encode most X86 instructions.
 */
public class AMD64Assembler extends Assembler {

    private static final int MinEncodingNeedsRex = 8;

    
The x86 condition codes used for conditional jumps/moves.
/**
     * The x86 condition codes used for conditional jumps/moves.
     */
    public enum ConditionFlag {
        Zero(0x4, "|zero|"),
        NotZero(0x5, "|nzero|"),
        Equal(0x4, "="),
        NotEqual(0x5, "!="),
        Less(0xc, "<"),
        LessEqual(0xe, "<="),
        Greater(0xf, ">"),
        GreaterEqual(0xd, ">="),
        Below(0x2, "|<|"),
        BelowEqual(0x6, "|<=|"),
        Above(0x7, "|>|"),
        AboveEqual(0x3, "|>=|"),
        Overflow(0x0, "|of|"),
        NoOverflow(0x1, "|nof|"),
        CarrySet(0x2, "|carry|"),
        CarryClear(0x3, "|ncarry|"),
        Negative(0x8, "|neg|"),
        Positive(0x9, "|pos|"),
        Parity(0xa, "|par|"),
        NoParity(0xb, "|npar|");

        private final int value;
        private final String operator;

        ConditionFlag(int value, String operator) {
            this.value = value;
            this.operator = operator;
        }

        public ConditionFlag negate() {
            switch (this) {
                case Zero:
                    return NotZero;
                case NotZero:
                    return Zero;
                case Equal:
                    return NotEqual;
                case NotEqual:
                    return Equal;
                case Less:
                    return GreaterEqual;
                case LessEqual:
                    return Greater;
                case Greater:
                    return LessEqual;
                case GreaterEqual:
                    return Less;
                case Below:
                    return AboveEqual;
                case BelowEqual:
                    return Above;
                case Above:
                    return BelowEqual;
                case AboveEqual:
                    return Below;
                case Overflow:
                    return NoOverflow;
                case NoOverflow:
                    return Overflow;
                case CarrySet:
                    return CarryClear;
                case CarryClear:
                    return CarrySet;
                case Negative:
                    return Positive;
                case Positive:
                    return Negative;
                case Parity:
                    return NoParity;
                case NoParity:
                    return Parity;
            }
            throw new IllegalArgumentException();
        }

        public int getValue() {
            return value;
        }

        @Override
        public String toString() {
            return operator;
        }
    }

    
Constants for X86 prefix bytes.
/**
     * Constants for X86 prefix bytes.
     */
    private static class Prefix {
        private static final int REX = 0x40;
        private static final int REXB = 0x41;
        private static final int REXX = 0x42;
        private static final int REXXB = 0x43;
        private static final int REXR = 0x44;
        private static final int REXRB = 0x45;
        private static final int REXRX = 0x46;
        private static final int REXRXB = 0x47;
        private static final int REXW = 0x48;
        private static final int REXWB = 0x49;
        private static final int REXWX = 0x4A;
        private static final int REXWXB = 0x4B;
        private static final int REXWR = 0x4C;
        private static final int REXWRB = 0x4D;
        private static final int REXWRX = 0x4E;
        private static final int REXWRXB = 0x4F;
        private static final int VEX_3BYTES = 0xC4;
        private static final int VEX_2BYTES = 0xC5;
    }

    private static class VexPrefix {
        private static final int VEX_R = 0x80;
        private static final int VEX_W = 0x80;
    }

    private static class AvxVectorLen {
        private static final int AVX_128bit = 0x0;
        private static final int AVX_256bit = 0x1;
    }

    private static class VexSimdPrefix {
        private static final int VEX_SIMD_NONE = 0x0;
        private static final int VEX_SIMD_66 = 0x1;
        private static final int VEX_SIMD_F3 = 0x2;
        private static final int VEX_SIMD_F2 = 0x3;
    }

    private static class VexOpcode {
        private static final int VEX_OPCODE_NONE = 0x0;
        private static final int VEX_OPCODE_0F = 0x1;
        private static final int VEX_OPCODE_0F_38 = 0x2;
        private static final int VEX_OPCODE_0F_3A = 0x3;
    }

    private AMD64InstructionAttr curAttributes;

    AMD64InstructionAttr getCurAttributes() {
        return curAttributes;
    }

    void setCurAttributes(AMD64InstructionAttr attributes) {
        curAttributes = attributes;
    }

    
The x86 operand sizes.
/**
     * The x86 operand sizes.
     */
    public enum OperandSize {
        BYTE(1) {
            @Override
            protected void emitImmediate(AMD64Assembler asm, int imm) {
                assert imm == (byte) imm;
                asm.emitByte(imm);
            }

            @Override
            protected int immediateSize() {
                return 1;
            }
        },

        WORD(2, 0x66) {
            @Override
            protected void emitImmediate(AMD64Assembler asm, int imm) {
                assert imm == (short) imm;
                asm.emitShort(imm);
            }

            @Override
            protected int immediateSize() {
                return 2;
            }
        },

        DWORD(4) {
            @Override
            protected void emitImmediate(AMD64Assembler asm, int imm) {
                asm.emitInt(imm);
            }

            @Override
            protected int immediateSize() {
                return 4;
            }
        },

        QWORD(8) {
            @Override
            protected void emitImmediate(AMD64Assembler asm, int imm) {
                asm.emitInt(imm);
            }

            @Override
            protected int immediateSize() {
                return 4;
            }
        },

        SS(4, 0xF3, true),

        SD(8, 0xF2, true),

        PS(16, true),

        PD(16, 0x66, true);

        private final int sizePrefix;

        private final int bytes;
        private final boolean xmm;

        OperandSize(int bytes) {
            this(bytes, 0);
        }

        OperandSize(int bytes, int sizePrefix) {
            this(bytes, sizePrefix, false);
        }

        OperandSize(int bytes, boolean xmm) {
            this(bytes, 0, xmm);
        }

        OperandSize(int bytes, int sizePrefix, boolean xmm) {
            this.sizePrefix = sizePrefix;
            this.bytes = bytes;
            this.xmm = xmm;
        }

        public int getBytes() {
            return bytes;
        }

        public boolean isXmmType() {
            return xmm;
        }

        
Emit an immediate of this size. Note that immediate QWORD operands are encoded as sign-extended 32-bit values. 
Params:
asm – 
imm – /**
         * Emit an immediate of this size. Note that immediate {@link #QWORD} operands are encoded
         * as sign-extended 32-bit values.
         *
         * @param asm
         * @param imm
         */
        protected void emitImmediate(AMD64Assembler asm, int imm) {
            throw new UnsupportedOperationException();
        }

        protected int immediateSize() {
            throw new UnsupportedOperationException();
        }
    }

    
Operand size and register type constraints.
/**
     * Operand size and register type constraints.
     */
    private enum OpAssertion {
        ByteAssertion(CPU, CPU, BYTE),
        IntegerAssertion(CPU, CPU, WORD, DWORD, QWORD),
        No16BitAssertion(CPU, CPU, DWORD, QWORD),
        No32BitAssertion(CPU, CPU, WORD, QWORD),
        QwordOnlyAssertion(CPU, CPU, QWORD),
        FloatingAssertion(XMM, XMM, SS, SD, PS, PD),
        PackedFloatingAssertion(XMM, XMM, PS, PD),
        SingleAssertion(XMM, XMM, SS),
        DoubleAssertion(XMM, XMM, SD),
        PackedDoubleAssertion(XMM, XMM, PD),
        IntToFloatingAssertion(XMM, CPU, DWORD, QWORD),
        FloatingToIntAssertion(CPU, XMM, DWORD, QWORD);

        private final RegisterCategory resultCategory;
        private final RegisterCategory inputCategory;
        private final OperandSize[] allowedSizes;

        OpAssertion(RegisterCategory resultCategory, RegisterCategory inputCategory, OperandSize... allowedSizes) {
            this.resultCategory = resultCategory;
            this.inputCategory = inputCategory;
            this.allowedSizes = allowedSizes;
        }

        protected boolean checkOperands(AMD64Op op, OperandSize size, Register resultReg, Register inputReg) {
            assert resultReg == null || resultCategory.equals(resultReg.getRegisterCategory()) : "invalid result register " + resultReg + " used in " + op;
            assert inputReg == null || inputCategory.equals(inputReg.getRegisterCategory()) : "invalid input register " + inputReg + " used in " + op;

            for (OperandSize s : allowedSizes) {
                if (size == s) {
                    return true;
                }
            }

            assert false : "invalid operand size " + size + " used in " + op;
            return false;
        }
    }

    public abstract static class OperandDataAnnotation extends CodeAnnotation {
        
The position (bytes from the beginning of the method) of the operand.
/**
         * The position (bytes from the beginning of the method) of the operand.
         */
        public final int operandPosition;
        
The size of the operand, in bytes.
/**
         * The size of the operand, in bytes.
         */
        public final int operandSize;
        
The position (bytes from the beginning of the method) of the next instruction. On AMD64,
RIP-relative operands are relative to this position.
/**
         * The position (bytes from the beginning of the method) of the next instruction. On AMD64,
         * RIP-relative operands are relative to this position.
         */
        public final int nextInstructionPosition;

        OperandDataAnnotation(int instructionPosition, int operandPosition, int operandSize, int nextInstructionPosition) {
            super(instructionPosition);

            this.operandPosition = operandPosition;
            this.operandSize = operandSize;
            this.nextInstructionPosition = nextInstructionPosition;
        }

        @Override
        public String toString() {
            return getClass().getSimpleName() + " instruction [" + instructionPosition + ", " + nextInstructionPosition + "[ operand at " + operandPosition + " size " + operandSize;
        }
    }

    
Annotation that stores additional information about the displacement of a placeholder address that needs patching. /**
     * Annotation that stores additional information about the displacement of a
     * {@link Assembler#getPlaceholder placeholder address} that needs patching.
     */
    public static class AddressDisplacementAnnotation extends OperandDataAnnotation {
        AddressDisplacementAnnotation(int instructionPosition, int operandPosition, int operndSize, int nextInstructionPosition) {
            super(instructionPosition, operandPosition, operndSize, nextInstructionPosition);
        }
    }

    
Annotation that stores additional information about the immediate operand, e.g., of a call
instruction, that needs patching.
/**
     * Annotation that stores additional information about the immediate operand, e.g., of a call
     * instruction, that needs patching.
     */
    public static class ImmediateOperandAnnotation extends OperandDataAnnotation {
        ImmediateOperandAnnotation(int instructionPosition, int operandPosition, int operndSize, int nextInstructionPosition) {
            super(instructionPosition, operandPosition, operndSize, nextInstructionPosition);
        }
    }

    
Constructs an assembler for the AMD64 architecture.
/**
     * Constructs an assembler for the AMD64 architecture.
     */
    public AMD64Assembler(TargetDescription target) {
        super(target);
    }

    public boolean supports(CPUFeature feature) {
        return ((AMD64) target.arch).getFeatures().contains(feature);
    }

    private static int encode(Register r) {
        assert r.encoding < 16 && r.encoding >= 0 : "encoding out of range: " + r.encoding;
        return r.encoding & 0x7;
    }

    
Get RXB bits for register-register instruction. In that encoding, ModRM.rm contains a
register index. The R bit extends the ModRM.reg field and the B bit extends the ModRM.rm
field. The X bit must be 0.
/**
     * Get RXB bits for register-register instruction. In that encoding, ModRM.rm contains a
     * register index. The R bit extends the ModRM.reg field and the B bit extends the ModRM.rm
     * field. The X bit must be 0.
     */
    protected static int getRXB(Register reg, Register rm) {
        int rxb = (reg == null ? 0 : reg.encoding & 0x08) >> 1;
        rxb |= (rm == null ? 0 : rm.encoding & 0x08) >> 3;
        return rxb;
    }

    
Get RXB bits for register-memory instruction. The R bit extends the ModRM.reg field. There
are two cases for the memory operand:

ModRM.rm contains the base register: In that case, B extends the ModRM.rm field and X = 0.


There is an SIB byte: In that case, X extends SIB.index and B extends SIB.base.
/**
     * Get RXB bits for register-memory instruction. The R bit extends the ModRM.reg field. There
     * are two cases for the memory operand:<br>
     * ModRM.rm contains the base register: In that case, B extends the ModRM.rm field and X = 0.
     * <br>
     * There is an SIB byte: In that case, X extends SIB.index and B extends SIB.base.
     */
    protected static int getRXB(Register reg, AMD64Address rm) {
        int rxb = (reg == null ? 0 : reg.encoding & 0x08) >> 1;
        if (!rm.getIndex().equals(Register.None)) {
            rxb |= (rm.getIndex().encoding & 0x08) >> 2;
        }
        if (!rm.getBase().equals(Register.None)) {
            rxb |= (rm.getBase().encoding & 0x08) >> 3;
        }
        return rxb;
    }

    
Emit the ModR/M byte for one register operand and an opcode extension in the R field.

Format: [ 11 reg r/m ]
/**
     * Emit the ModR/M byte for one register operand and an opcode extension in the R field.
     * <p>
     * Format: [ 11 reg r/m ]
     */
    protected void emitModRM(int reg, Register rm) {
        assert (reg & 0x07) == reg;
        emitByte(0xC0 | (reg << 3) | (rm.encoding & 0x07));
    }

    
Emit the ModR/M byte for two register operands.

Format: [ 11 reg r/m ]
/**
     * Emit the ModR/M byte for two register operands.
     * <p>
     * Format: [ 11 reg r/m ]
     */
    protected void emitModRM(Register reg, Register rm) {
        emitModRM(reg.encoding & 0x07, rm);
    }

    protected void emitOperandHelper(Register reg, AMD64Address addr, int additionalInstructionSize) {
        assert !reg.equals(Register.None);
        emitOperandHelper(encode(reg), addr, false, additionalInstructionSize);
    }

    
Emits the ModR/M byte and optionally the SIB byte for one register and one memory operand.
Params:
force4Byte – use 4 byte encoding for displacements that would normally fit in a byte/**
     * Emits the ModR/M byte and optionally the SIB byte for one register and one memory operand.
     *
     * @param force4Byte use 4 byte encoding for displacements that would normally fit in a byte
     */
    protected void emitOperandHelper(Register reg, AMD64Address addr, boolean force4Byte, int additionalInstructionSize) {
        assert !reg.equals(Register.None);
        emitOperandHelper(encode(reg), addr, force4Byte, additionalInstructionSize);
    }

    protected void emitOperandHelper(int reg, AMD64Address addr, int additionalInstructionSize) {
        emitOperandHelper(reg, addr, false, additionalInstructionSize);
    }

    
Emits the ModR/M byte and optionally the SIB byte for one memory operand and an opcode
extension in the R field.
Params:
force4Byte – use 4 byte encoding for displacements that would normally fit in a byte
additionalInstructionSize – the number of bytes that will be emitted after the operand,
           so that the start position of the next instruction can be computed even though
           this instruction has not been completely emitted yet./**
     * Emits the ModR/M byte and optionally the SIB byte for one memory operand and an opcode
     * extension in the R field.
     *
     * @param force4Byte use 4 byte encoding for displacements that would normally fit in a byte
     * @param additionalInstructionSize the number of bytes that will be emitted after the operand,
     *            so that the start position of the next instruction can be computed even though
     *            this instruction has not been completely emitted yet.
     */
    protected void emitOperandHelper(int reg, AMD64Address addr, boolean force4Byte, int additionalInstructionSize) {
        assert (reg & 0x07) == reg;
        int regenc = reg << 3;

        Register base = addr.getBase();
        Register index = addr.getIndex();

        AMD64Address.Scale scale = addr.getScale();
        int disp = addr.getDisplacement();

        if (base.equals(AMD64.rip)) { // also matches addresses returned by getPlaceholder()
            // [00 000 101] disp32
            assert index.equals(Register.None) : "cannot use RIP relative addressing with index register";
            emitByte(0x05 | regenc);
            if (codePatchingAnnotationConsumer != null && addr.instructionStartPosition >= 0) {
                codePatchingAnnotationConsumer.accept(new AddressDisplacementAnnotation(addr.instructionStartPosition, position(), 4, position() + 4 + additionalInstructionSize));
            }
            emitInt(disp);
        } else if (base.isValid()) {
            int baseenc = base.isValid() ? encode(base) : 0;
            if (index.isValid()) {
                int indexenc = encode(index) << 3;
                // [base + indexscale + disp]
                if (disp == 0 && !base.equals(rbp) && !base.equals(r13)) {
                    // [base + indexscale]
                    // [00 reg 100][ss index base]
                    assert !index.equals(rsp) : "illegal addressing mode";
                    emitByte(0x04 | regenc);
                    emitByte(scale.log2 << 6 | indexenc | baseenc);
                } else if (isByte(disp) && !force4Byte) {
                    // [base + indexscale + imm8]
                    // [01 reg 100][ss index base] imm8
                    assert !index.equals(rsp) : "illegal addressing mode";
                    emitByte(0x44 | regenc);
                    emitByte(scale.log2 << 6 | indexenc | baseenc);
                    emitByte(disp & 0xFF);
                } else {
                    // [base + indexscale + disp32]
                    // [10 reg 100][ss index base] disp32
                    assert !index.equals(rsp) : "illegal addressing mode";
                    emitByte(0x84 | regenc);
                    emitByte(scale.log2 << 6 | indexenc | baseenc);
                    emitInt(disp);
                }
            } else if (base.equals(rsp) || base.equals(r12)) {
                // [rsp + disp]
                if (disp == 0) {
                    // [rsp]
                    // [00 reg 100][00 100 100]
                    emitByte(0x04 | regenc);
                    emitByte(0x24);
                } else if (isByte(disp) && !force4Byte) {
                    // [rsp + imm8]
                    // [01 reg 100][00 100 100] disp8
                    emitByte(0x44 | regenc);
                    emitByte(0x24);
                    emitByte(disp & 0xFF);
                } else {
                    // [rsp + imm32]
                    // [10 reg 100][00 100 100] disp32
                    emitByte(0x84 | regenc);
                    emitByte(0x24);
                    emitInt(disp);
                }
            } else {
                // [base + disp]
                assert !base.equals(rsp) && !base.equals(r12) : "illegal addressing mode";
                if (disp == 0 && !base.equals(rbp) && !base.equals(r13)) {
                    // [base]
                    // [00 reg base]
                    emitByte(0x00 | regenc | baseenc);
                } else if (isByte(disp) && !force4Byte) {
                    // [base + disp8]
                    // [01 reg base] disp8
                    emitByte(0x40 | regenc | baseenc);
                    emitByte(disp & 0xFF);
                } else {
                    // [base + disp32]
                    // [10 reg base] disp32
                    emitByte(0x80 | regenc | baseenc);
                    emitInt(disp);
                }
            }
        } else {
            if (index.isValid()) {
                int indexenc = encode(index) << 3;
                // [indexscale + disp]
                // [00 reg 100][ss index 101] disp32
                assert !index.equals(rsp) : "illegal addressing mode";
                emitByte(0x04 | regenc);
                emitByte(scale.log2 << 6 | indexenc | 0x05);
                emitInt(disp);
            } else {
                // [disp] ABSOLUTE
                // [00 reg 100][00 100 101] disp32
                emitByte(0x04 | regenc);
                emitByte(0x25);
                emitInt(disp);
            }
        }
        setCurAttributes(null);
    }

    
Base class for AMD64 opcodes.
/**
     * Base class for AMD64 opcodes.
     */
    public static class AMD64Op {

        protected static final int P_0F = 0x0F;
        protected static final int P_0F38 = 0x380F;
        protected static final int P_0F3A = 0x3A0F;

        private final String opcode;

        protected final int prefix1;
        protected final int prefix2;
        protected final int op;

        private final boolean dstIsByte;
        private final boolean srcIsByte;

        private final OpAssertion assertion;
        private final CPUFeature feature;

        protected AMD64Op(String opcode, int prefix1, int prefix2, int op, OpAssertion assertion, CPUFeature feature) {
            this(opcode, prefix1, prefix2, op, assertion == OpAssertion.ByteAssertion, assertion == OpAssertion.ByteAssertion, assertion, feature);
        }

        protected AMD64Op(String opcode, int prefix1, int prefix2, int op, boolean dstIsByte, boolean srcIsByte, OpAssertion assertion, CPUFeature feature) {
            this.opcode = opcode;
            this.prefix1 = prefix1;
            this.prefix2 = prefix2;
            this.op = op;

            this.dstIsByte = dstIsByte;
            this.srcIsByte = srcIsByte;

            this.assertion = assertion;
            this.feature = feature;
        }

        protected final void emitOpcode(AMD64Assembler asm, OperandSize size, int rxb, int dstEnc, int srcEnc) {
            if (prefix1 != 0) {
                asm.emitByte(prefix1);
            }
            if (size.sizePrefix != 0) {
                asm.emitByte(size.sizePrefix);
            }
            int rexPrefix = 0x40 | rxb;
            if (size == QWORD) {
                rexPrefix |= 0x08;
            }
            if (rexPrefix != 0x40 || (dstIsByte && dstEnc >= 4) || (srcIsByte && srcEnc >= 4)) {
                asm.emitByte(rexPrefix);
            }
            if (prefix2 > 0xFF) {
                asm.emitShort(prefix2);
            } else if (prefix2 > 0) {
                asm.emitByte(prefix2);
            }
            asm.emitByte(op);
        }

        protected final boolean verify(AMD64Assembler asm, OperandSize size, Register resultReg, Register inputReg) {
            assert feature == null || asm.supports(feature) : String.format("unsupported feature %s required for %s", feature, opcode);
            assert assertion.checkOperands(this, size, resultReg, inputReg);
            return true;
        }

        @Override
        public String toString() {
            return opcode;
        }
    }

    
Base class for AMD64 opcodes with immediate operands.
/**
     * Base class for AMD64 opcodes with immediate operands.
     */
    public static class AMD64ImmOp extends AMD64Op {

        private final boolean immIsByte;

        protected AMD64ImmOp(String opcode, boolean immIsByte, int prefix, int op, OpAssertion assertion) {
            super(opcode, 0, prefix, op, assertion, null);
            this.immIsByte = immIsByte;
        }

        protected final void emitImmediate(AMD64Assembler asm, OperandSize size, int imm) {
            if (immIsByte) {
                assert imm == (byte) imm;
                asm.emitByte(imm);
            } else {
                size.emitImmediate(asm, imm);
            }
        }

        protected final int immediateSize(OperandSize size) {
            if (immIsByte) {
                return 1;
            } else {
                return size.bytes;
            }
        }
    }

    
Opcode with operand order of either RM or MR for 2 address forms.
/**
     * Opcode with operand order of either RM or MR for 2 address forms.
     */
    public abstract static class AMD64RROp extends AMD64Op {

        protected AMD64RROp(String opcode, int prefix1, int prefix2, int op, OpAssertion assertion, CPUFeature feature) {
            super(opcode, prefix1, prefix2, op, assertion, feature);
        }

        protected AMD64RROp(String opcode, int prefix1, int prefix2, int op, boolean dstIsByte, boolean srcIsByte, OpAssertion assertion, CPUFeature feature) {
            super(opcode, prefix1, prefix2, op, dstIsByte, srcIsByte, assertion, feature);
        }

        public abstract void emit(AMD64Assembler asm, OperandSize size, Register dst, Register src);
    }

    
Opcode with operand order of either RM or MR for 3 address forms.
/**
     * Opcode with operand order of either RM or MR for 3 address forms.
     */
    public abstract static class AMD64RRROp extends AMD64Op {

        protected AMD64RRROp(String opcode, int prefix1, int prefix2, int op, OpAssertion assertion, CPUFeature feature) {
            super(opcode, prefix1, prefix2, op, assertion, feature);
        }

        protected AMD64RRROp(String opcode, int prefix1, int prefix2, int op, boolean dstIsByte, boolean srcIsByte, OpAssertion assertion, CPUFeature feature) {
            super(opcode, prefix1, prefix2, op, dstIsByte, srcIsByte, assertion, feature);
        }

        public abstract void emit(AMD64Assembler asm, OperandSize size, Register dst, Register nds, Register src);
    }

    
Opcode with operand order of RM.
/**
     * Opcode with operand order of RM.
     */
    public static class AMD64RMOp extends AMD64RROp {
        // @formatter:off
        public static final AMD64RMOp IMUL   = new AMD64RMOp("IMUL",         P_0F, 0xAF);
        public static final AMD64RMOp BSF    = new AMD64RMOp("BSF",          P_0F, 0xBC);
        public static final AMD64RMOp BSR    = new AMD64RMOp("BSR",          P_0F, 0xBD);
        public static final AMD64RMOp POPCNT = new AMD64RMOp("POPCNT", 0xF3, P_0F, 0xB8, CPUFeature.POPCNT);
        public static final AMD64RMOp TZCNT  = new AMD64RMOp("TZCNT",  0xF3, P_0F, 0xBC, CPUFeature.BMI1);
        public static final AMD64RMOp LZCNT  = new AMD64RMOp("LZCNT",  0xF3, P_0F, 0xBD, CPUFeature.LZCNT);
        public static final AMD64RMOp MOVZXB = new AMD64RMOp("MOVZXB",       P_0F, 0xB6, false, true, OpAssertion.IntegerAssertion);
        public static final AMD64RMOp MOVZX  = new AMD64RMOp("MOVZX",        P_0F, 0xB7, OpAssertion.No16BitAssertion);
        public static final AMD64RMOp MOVSXB = new AMD64RMOp("MOVSXB",       P_0F, 0xBE, false, true, OpAssertion.IntegerAssertion);
        public static final AMD64RMOp MOVSX  = new AMD64RMOp("MOVSX",        P_0F, 0xBF, OpAssertion.No16BitAssertion);
        public static final AMD64RMOp MOVSXD = new AMD64RMOp("MOVSXD",             0x63, OpAssertion.QwordOnlyAssertion);
        public static final AMD64RMOp MOVB   = new AMD64RMOp("MOVB",               0x8A, OpAssertion.ByteAssertion);
        public static final AMD64RMOp MOV    = new AMD64RMOp("MOV",                0x8B);

        // MOVD/MOVQ and MOVSS/MOVSD are the same opcode, just with different operand size prefix
        public static final AMD64RMOp MOVD   = new AMD64RMOp("MOVD",   0x66, P_0F, 0x6E, OpAssertion.IntToFloatingAssertion, CPUFeature.SSE2);
        public static final AMD64RMOp MOVQ   = new AMD64RMOp("MOVQ",   0x66, P_0F, 0x6E, OpAssertion.IntToFloatingAssertion, CPUFeature.SSE2);
        public static final AMD64RMOp MOVSS  = new AMD64RMOp("MOVSS",        P_0F, 0x10, OpAssertion.FloatingAssertion, CPUFeature.SSE);
        public static final AMD64RMOp MOVSD  = new AMD64RMOp("MOVSD",        P_0F, 0x10, OpAssertion.FloatingAssertion, CPUFeature.SSE);

        // TEST is documented as MR operation, but it's symmetric, and using it as RM operation is more convenient.
        public static final AMD64RMOp TESTB  = new AMD64RMOp("TEST",               0x84, OpAssertion.ByteAssertion);
        public static final AMD64RMOp TEST   = new AMD64RMOp("TEST",               0x85);
        // @formatter:on

        protected AMD64RMOp(String opcode, int op) {
            this(opcode, 0, op);
        }

        protected AMD64RMOp(String opcode, int op, OpAssertion assertion) {
            this(opcode, 0, op, assertion);
        }

        protected AMD64RMOp(String opcode, int prefix, int op) {
            this(opcode, 0, prefix, op, null);
        }

        protected AMD64RMOp(String opcode, int prefix, int op, OpAssertion assertion) {
            this(opcode, 0, prefix, op, assertion, null);
        }

        protected AMD64RMOp(String opcode, int prefix, int op, OpAssertion assertion, CPUFeature feature) {
            this(opcode, 0, prefix, op, assertion, feature);
        }

        protected AMD64RMOp(String opcode, int prefix, int op, boolean dstIsByte, boolean srcIsByte, OpAssertion assertion) {
            super(opcode, 0, prefix, op, dstIsByte, srcIsByte, assertion, null);
        }

        protected AMD64RMOp(String opcode, int prefix1, int prefix2, int op, CPUFeature feature) {
            this(opcode, prefix1, prefix2, op, OpAssertion.IntegerAssertion, feature);
        }

        protected AMD64RMOp(String opcode, int prefix1, int prefix2, int op, OpAssertion assertion, CPUFeature feature) {
            super(opcode, prefix1, prefix2, op, assertion, feature);
        }

        @Override
        public final void emit(AMD64Assembler asm, OperandSize size, Register dst, Register src) {
            assert verify(asm, size, dst, src);
            boolean isSimd = false;
            boolean noNds = false;

            switch (op) {
                case 0x2A:
                case 0x2C:
                case 0x2E:
                case 0x5A:
                case 0x6E:
                    isSimd = true;
                    noNds = true;
                    break;
                case 0x10:
                case 0x51:
                case 0x54:
                case 0x55:
                case 0x56:
                case 0x57:
                case 0x58:
                case 0x59:
                case 0x5C:
                case 0x5D:
                case 0x5E:
                case 0x5F:
                    isSimd = true;
                    break;
            }

            if (isSimd) {
                int pre;
                int opc;
                boolean rexVexW = (size == QWORD) ? true : false;
                AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, rexVexW, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, asm.target);
                int curPrefix = size.sizePrefix | prefix1;
                switch (curPrefix) {
                    case 0x66:
                        pre = VexSimdPrefix.VEX_SIMD_66;
                        break;
                    case 0xF2:
                        pre = VexSimdPrefix.VEX_SIMD_F2;
                        break;
                    case 0xF3:
                        pre = VexSimdPrefix.VEX_SIMD_F3;
                        break;
                    default:
                        pre = VexSimdPrefix.VEX_SIMD_NONE;
                        break;
                }
                switch (prefix2) {
                    case P_0F:
                        opc = VexOpcode.VEX_OPCODE_0F;
                        break;
                    case P_0F38:
                        opc = VexOpcode.VEX_OPCODE_0F_38;
                        break;
                    case P_0F3A:
                        opc = VexOpcode.VEX_OPCODE_0F_3A;
                        break;
                    default:
                        opc = VexOpcode.VEX_OPCODE_NONE;
                        break;
                }
                int encode;
                if (noNds) {
                    encode = asm.simdPrefixAndEncode(dst, Register.None, src, pre, opc, attributes);
                } else {
                    encode = asm.simdPrefixAndEncode(dst, dst, src, pre, opc, attributes);
                }
                asm.emitByte(op);
                asm.emitByte(0xC0 | encode);
            } else {
                emitOpcode(asm, size, getRXB(dst, src), dst.encoding, src.encoding);
                asm.emitModRM(dst, src);
            }
        }

        public final void emit(AMD64Assembler asm, OperandSize size, Register dst, AMD64Address src) {
            assert verify(asm, size, dst, null);
            boolean isSimd = false;
            boolean noNds = false;

            switch (op) {
                case 0x10:
                case 0x2A:
                case 0x2C:
                case 0x2E:
                case 0x6E:
                    isSimd = true;
                    noNds = true;
                    break;
                case 0x51:
                case 0x54:
                case 0x55:
                case 0x56:
                case 0x57:
                case 0x58:
                case 0x59:
                case 0x5C:
                case 0x5D:
                case 0x5E:
                case 0x5F:
                    isSimd = true;
                    break;
            }

            if (isSimd) {
                int pre;
                int opc;
                boolean rexVexW = (size == QWORD) ? true : false;
                AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, rexVexW, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, asm.target);
                int curPrefix = size.sizePrefix | prefix1;
                switch (curPrefix) {
                    case 0x66:
                        pre = VexSimdPrefix.VEX_SIMD_66;
                        break;
                    case 0xF2:
                        pre = VexSimdPrefix.VEX_SIMD_F2;
                        break;
                    case 0xF3:
                        pre = VexSimdPrefix.VEX_SIMD_F3;
                        break;
                    default:
                        pre = VexSimdPrefix.VEX_SIMD_NONE;
                        break;
                }
                switch (prefix2) {
                    case P_0F:
                        opc = VexOpcode.VEX_OPCODE_0F;
                        break;
                    case P_0F38:
                        opc = VexOpcode.VEX_OPCODE_0F_38;
                        break;
                    case P_0F3A:
                        opc = VexOpcode.VEX_OPCODE_0F_3A;
                        break;
                    default:
                        opc = VexOpcode.VEX_OPCODE_NONE;
                        break;
                }
                if (noNds) {
                    asm.simdPrefix(dst, Register.None, src, pre, opc, attributes);
                } else {
                    asm.simdPrefix(dst, dst, src, pre, opc, attributes);
                }
                asm.emitByte(op);
                asm.emitOperandHelper(dst, src, 0);
            } else {
                emitOpcode(asm, size, getRXB(dst, src), dst.encoding, 0);
                asm.emitOperandHelper(dst, src, 0);
            }
        }
    }

    
Opcode with operand order of RM.
/**
     * Opcode with operand order of RM.
     */
    public static class AMD64RRMOp extends AMD64RRROp {
        protected AMD64RRMOp(String opcode, int op) {
            this(opcode, 0, op);
        }

        protected AMD64RRMOp(String opcode, int op, OpAssertion assertion) {
            this(opcode, 0, op, assertion);
        }

        protected AMD64RRMOp(String opcode, int prefix, int op) {
            this(opcode, 0, prefix, op, null);
        }

        protected AMD64RRMOp(String opcode, int prefix, int op, OpAssertion assertion) {
            this(opcode, 0, prefix, op, assertion, null);
        }

        protected AMD64RRMOp(String opcode, int prefix, int op, OpAssertion assertion, CPUFeature feature) {
            this(opcode, 0, prefix, op, assertion, feature);
        }

        protected AMD64RRMOp(String opcode, int prefix, int op, boolean dstIsByte, boolean srcIsByte, OpAssertion assertion) {
            super(opcode, 0, prefix, op, dstIsByte, srcIsByte, assertion, null);
        }

        protected AMD64RRMOp(String opcode, int prefix1, int prefix2, int op, CPUFeature feature) {
            this(opcode, prefix1, prefix2, op, OpAssertion.IntegerAssertion, feature);
        }

        protected AMD64RRMOp(String opcode, int prefix1, int prefix2, int op, OpAssertion assertion, CPUFeature feature) {
            super(opcode, prefix1, prefix2, op, assertion, feature);
        }

        @Override
        public final void emit(AMD64Assembler asm, OperandSize size, Register dst, Register nds, Register src) {
            assert verify(asm, size, dst, src);
            int pre;
            int opc;
            boolean rexVexW = (size == QWORD) ? true : false;
            AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, rexVexW, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, asm.target);
            int curPrefix = size.sizePrefix | prefix1;
            switch (curPrefix) {
                case 0x66:
                    pre = VexSimdPrefix.VEX_SIMD_66;
                    break;
                case 0xF2:
                    pre = VexSimdPrefix.VEX_SIMD_F2;
                    break;
                case 0xF3:
                    pre = VexSimdPrefix.VEX_SIMD_F3;
                    break;
                default:
                    pre = VexSimdPrefix.VEX_SIMD_NONE;
                    break;
            }
            switch (prefix2) {
                case P_0F:
                    opc = VexOpcode.VEX_OPCODE_0F;
                    break;
                case P_0F38:
                    opc = VexOpcode.VEX_OPCODE_0F_38;
                    break;
                case P_0F3A:
                    opc = VexOpcode.VEX_OPCODE_0F_3A;
                    break;
                default:
                    opc = VexOpcode.VEX_OPCODE_NONE;
                    break;
            }
            int encode;
            encode = asm.simdPrefixAndEncode(dst, nds, src, pre, opc, attributes);
            asm.emitByte(op);
            asm.emitByte(0xC0 | encode);
        }

        public final void emit(AMD64Assembler asm, OperandSize size, Register dst, Register nds, AMD64Address src) {
            assert verify(asm, size, dst, null);
            int pre;
            int opc;
            boolean rexVexW = (size == QWORD) ? true : false;
            AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, rexVexW, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, asm.target);
            int curPrefix = size.sizePrefix | prefix1;
            switch (curPrefix) {
                case 0x66:
                    pre = VexSimdPrefix.VEX_SIMD_66;
                    break;
                case 0xF2:
                    pre = VexSimdPrefix.VEX_SIMD_F2;
                    break;
                case 0xF3:
                    pre = VexSimdPrefix.VEX_SIMD_F3;
                    break;
                default:
                    pre = VexSimdPrefix.VEX_SIMD_NONE;
                    break;
            }
            switch (prefix2) {
                case P_0F:
                    opc = VexOpcode.VEX_OPCODE_0F;
                    break;
                case P_0F38:
                    opc = VexOpcode.VEX_OPCODE_0F_38;
                    break;
                case P_0F3A:
                    opc = VexOpcode.VEX_OPCODE_0F_3A;
                    break;
                default:
                    opc = VexOpcode.VEX_OPCODE_NONE;
                    break;
            }
            asm.simdPrefix(dst, nds, src, pre, opc, attributes);
            asm.emitByte(op);
            asm.emitOperandHelper(dst, src, 0);
        }
    }

    
Opcode with operand order of MR.
/**
     * Opcode with operand order of MR.
     */
    public static class AMD64MROp extends AMD64RROp {
        // @formatter:off
        public static final AMD64MROp MOVB   = new AMD64MROp("MOVB",               0x88, OpAssertion.ByteAssertion);
        public static final AMD64MROp MOV    = new AMD64MROp("MOV",                0x89);

        // MOVD and MOVQ are the same opcode, just with different operand size prefix
        // Note that as MR opcodes, they have reverse operand order, so the IntToFloatingAssertion must be used.
        public static final AMD64MROp MOVD   = new AMD64MROp("MOVD",   0x66, P_0F, 0x7E, OpAssertion.IntToFloatingAssertion, CPUFeature.SSE2);
        public static final AMD64MROp MOVQ   = new AMD64MROp("MOVQ",   0x66, P_0F, 0x7E, OpAssertion.IntToFloatingAssertion, CPUFeature.SSE2);

        // MOVSS and MOVSD are the same opcode, just with different operand size prefix
        public static final AMD64MROp MOVSS  = new AMD64MROp("MOVSS",        P_0F, 0x11, OpAssertion.FloatingAssertion, CPUFeature.SSE);
        public static final AMD64MROp MOVSD  = new AMD64MROp("MOVSD",        P_0F, 0x11, OpAssertion.FloatingAssertion, CPUFeature.SSE);
        // @formatter:on

        protected AMD64MROp(String opcode, int op) {
            this(opcode, 0, op);
        }

        protected AMD64MROp(String opcode, int op, OpAssertion assertion) {
            this(opcode, 0, op, assertion);
        }

        protected AMD64MROp(String opcode, int prefix, int op) {
            this(opcode, prefix, op, OpAssertion.IntegerAssertion);
        }

        protected AMD64MROp(String opcode, int prefix, int op, OpAssertion assertion) {
            this(opcode, prefix, op, assertion, null);
        }

        protected AMD64MROp(String opcode, int prefix, int op, OpAssertion assertion, CPUFeature feature) {
            this(opcode, 0, prefix, op, assertion, feature);
        }

        protected AMD64MROp(String opcode, int prefix1, int prefix2, int op, OpAssertion assertion, CPUFeature feature) {
            super(opcode, prefix1, prefix2, op, assertion, feature);
        }

        @Override
        public final void emit(AMD64Assembler asm, OperandSize size, Register dst, Register src) {
            assert verify(asm, size, src, dst);
            boolean isSimd = false;
            boolean noNds = false;

            switch (op) {
                case 0x7E:
                    isSimd = true;
                    noNds = true;
                    break;
                case 0x11:
                    isSimd = true;
                    break;
            }

            if (isSimd) {
                int pre;
                int opc;
                boolean rexVexW = (size == QWORD) ? true : false;
                AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, rexVexW, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, asm.target);
                int curPrefix = size.sizePrefix | prefix1;
                switch (curPrefix) {
                    case 0x66:
                        pre = VexSimdPrefix.VEX_SIMD_66;
                        break;
                    case 0xF2:
                        pre = VexSimdPrefix.VEX_SIMD_F2;
                        break;
                    case 0xF3:
                        pre = VexSimdPrefix.VEX_SIMD_F3;
                        break;
                    default:
                        pre = VexSimdPrefix.VEX_SIMD_NONE;
                        break;
                }
                switch (prefix2) {
                    case P_0F:
                        opc = VexOpcode.VEX_OPCODE_0F;
                        break;
                    case P_0F38:
                        opc = VexOpcode.VEX_OPCODE_0F_38;
                        break;
                    case P_0F3A:
                        opc = VexOpcode.VEX_OPCODE_0F_3A;
                        break;
                    default:
                        opc = VexOpcode.VEX_OPCODE_NONE;
                        break;
                }
                int encode;
                if (noNds) {
                    encode = asm.simdPrefixAndEncode(src, Register.None, dst, pre, opc, attributes);
                } else {
                    encode = asm.simdPrefixAndEncode(src, src, dst, pre, opc, attributes);
                }
                asm.emitByte(op);
                asm.emitByte(0xC0 | encode);
            } else {
                emitOpcode(asm, size, getRXB(src, dst), src.encoding, dst.encoding);
                asm.emitModRM(src, dst);
            }
        }

        public final void emit(AMD64Assembler asm, OperandSize size, AMD64Address dst, Register src) {
            assert verify(asm, size, null, src);
            boolean isSimd = false;

            switch (op) {
                case 0x7E:
                case 0x11:
                    isSimd = true;
                    break;
            }

            if (isSimd) {
                int pre;
                int opc;
                boolean rexVexW = (size == QWORD) ? true : false;
                AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, rexVexW, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, asm.target);
                int curPrefix = size.sizePrefix | prefix1;
                switch (curPrefix) {
                    case 0x66:
                        pre = VexSimdPrefix.VEX_SIMD_66;
                        break;
                    case 0xF2:
                        pre = VexSimdPrefix.VEX_SIMD_F2;
                        break;
                    case 0xF3:
                        pre = VexSimdPrefix.VEX_SIMD_F3;
                        break;
                    default:
                        pre = VexSimdPrefix.VEX_SIMD_NONE;
                        break;
                }
                switch (prefix2) {
                    case P_0F:
                        opc = VexOpcode.VEX_OPCODE_0F;
                        break;
                    case P_0F38:
                        opc = VexOpcode.VEX_OPCODE_0F_38;
                        break;
                    case P_0F3A:
                        opc = VexOpcode.VEX_OPCODE_0F_3A;
                        break;
                    default:
                        opc = VexOpcode.VEX_OPCODE_NONE;
                        break;
                }
                asm.simdPrefix(src, Register.None, dst, pre, opc, attributes);
                asm.emitByte(op);
                asm.emitOperandHelper(src, dst, 0);
            } else {
                emitOpcode(asm, size, getRXB(src, dst), src.encoding, 0);
                asm.emitOperandHelper(src, dst, 0);
            }
        }
    }

    
Opcodes with operand order of M.
/**
     * Opcodes with operand order of M.
     */
    public static class AMD64MOp extends AMD64Op {
        // @formatter:off
        public static final AMD64MOp NOT  = new AMD64MOp("NOT",  0xF7, 2);
        public static final AMD64MOp NEG  = new AMD64MOp("NEG",  0xF7, 3);
        public static final AMD64MOp MUL  = new AMD64MOp("MUL",  0xF7, 4);
        public static final AMD64MOp IMUL = new AMD64MOp("IMUL", 0xF7, 5);
        public static final AMD64MOp DIV  = new AMD64MOp("DIV",  0xF7, 6);
        public static final AMD64MOp IDIV = new AMD64MOp("IDIV", 0xF7, 7);
        public static final AMD64MOp INC  = new AMD64MOp("INC",  0xFF, 0);
        public static final AMD64MOp DEC  = new AMD64MOp("DEC",  0xFF, 1);
        public static final AMD64MOp PUSH = new AMD64MOp("PUSH", 0xFF, 6);
        public static final AMD64MOp POP  = new AMD64MOp("POP",  0x8F, 0, OpAssertion.No32BitAssertion);
        // @formatter:on

        private final int ext;

        protected AMD64MOp(String opcode, int op, int ext) {
            this(opcode, 0, op, ext);
        }

        protected AMD64MOp(String opcode, int prefix, int op, int ext) {
            this(opcode, prefix, op, ext, OpAssertion.IntegerAssertion);
        }

        protected AMD64MOp(String opcode, int op, int ext, OpAssertion assertion) {
            this(opcode, 0, op, ext, assertion);
        }

        protected AMD64MOp(String opcode, int prefix, int op, int ext, OpAssertion assertion) {
            super(opcode, 0, prefix, op, assertion, null);
            this.ext = ext;
        }

        public final void emit(AMD64Assembler asm, OperandSize size, Register dst) {
            assert verify(asm, size, dst, null);
            emitOpcode(asm, size, getRXB(null, dst), 0, dst.encoding);
            asm.emitModRM(ext, dst);
        }

        public final void emit(AMD64Assembler asm, OperandSize size, AMD64Address dst) {
            assert verify(asm, size, null, null);
            emitOpcode(asm, size, getRXB(null, dst), 0, 0);
            asm.emitOperandHelper(ext, dst, 0);
        }
    }

    
Opcodes with operand order of MI.
/**
     * Opcodes with operand order of MI.
     */
    public static class AMD64MIOp extends AMD64ImmOp {
        // @formatter:off
        public static final AMD64MIOp MOVB = new AMD64MIOp("MOVB", true,  0xC6, 0, OpAssertion.ByteAssertion);
        public static final AMD64MIOp MOV  = new AMD64MIOp("MOV",  false, 0xC7, 0);
        public static final AMD64MIOp TEST = new AMD64MIOp("TEST", false, 0xF7, 0);
        // @formatter:on

        private final int ext;

        protected AMD64MIOp(String opcode, boolean immIsByte, int op, int ext) {
            this(opcode, immIsByte, op, ext, OpAssertion.IntegerAssertion);
        }

        protected AMD64MIOp(String opcode, boolean immIsByte, int op, int ext, OpAssertion assertion) {
            this(opcode, immIsByte, 0, op, ext, assertion);
        }

        protected AMD64MIOp(String opcode, boolean immIsByte, int prefix, int op, int ext, OpAssertion assertion) {
            super(opcode, immIsByte, prefix, op, assertion);
            this.ext = ext;
        }

        public final void emit(AMD64Assembler asm, OperandSize size, Register dst, int imm) {
            assert verify(asm, size, dst, null);
            emitOpcode(asm, size, getRXB(null, dst), 0, dst.encoding);
            asm.emitModRM(ext, dst);
            emitImmediate(asm, size, imm);
        }

        public final void emit(AMD64Assembler asm, OperandSize size, AMD64Address dst, int imm) {
            assert verify(asm, size, null, null);
            emitOpcode(asm, size, getRXB(null, dst), 0, 0);
            asm.emitOperandHelper(ext, dst, immediateSize(size));
            emitImmediate(asm, size, imm);
        }
    }

    
Opcodes with operand order of RMI.
We only have one form of round as the operation is always treated with single variant input,
making its extension to 3 address forms redundant.
/**
     * Opcodes with operand order of RMI.
     *
     * We only have one form of round as the operation is always treated with single variant input,
     * making its extension to 3 address forms redundant.
     */
    public static class AMD64RMIOp extends AMD64ImmOp {
        // @formatter:off
        public static final AMD64RMIOp IMUL    = new AMD64RMIOp("IMUL", false, 0x69);
        public static final AMD64RMIOp IMUL_SX = new AMD64RMIOp("IMUL", true,  0x6B);
        public static final AMD64RMIOp ROUNDSS = new AMD64RMIOp("ROUNDSS", true, P_0F3A, 0x0A, OpAssertion.PackedDoubleAssertion);
        public static final AMD64RMIOp ROUNDSD = new AMD64RMIOp("ROUNDSD", true, P_0F3A, 0x0B, OpAssertion.PackedDoubleAssertion);
        // @formatter:on

        protected AMD64RMIOp(String opcode, boolean immIsByte, int op) {
            this(opcode, immIsByte, 0, op, OpAssertion.IntegerAssertion);
        }

        protected AMD64RMIOp(String opcode, boolean immIsByte, int prefix, int op, OpAssertion assertion) {
            super(opcode, immIsByte, prefix, op, assertion);
        }

        public final void emit(AMD64Assembler asm, OperandSize size, Register dst, Register src, int imm) {
            assert verify(asm, size, dst, src);
            boolean isSimd = false;
            boolean noNds = false;

            switch (op) {
                case 0x0A:
                case 0x0B:
                    isSimd = true;
                    noNds = true;
                    break;
            }

            if (isSimd) {
                int pre;
                int opc;
                AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, asm.target);
                int curPrefix = size.sizePrefix | prefix1;
                switch (curPrefix) {
                    case 0x66:
                        pre = VexSimdPrefix.VEX_SIMD_66;
                        break;
                    case 0xF2:
                        pre = VexSimdPrefix.VEX_SIMD_F2;
                        break;
                    case 0xF3:
                        pre = VexSimdPrefix.VEX_SIMD_F3;
                        break;
                    default:
                        pre = VexSimdPrefix.VEX_SIMD_NONE;
                        break;
                }
                switch (prefix2) {
                    case P_0F:
                        opc = VexOpcode.VEX_OPCODE_0F;
                        break;
                    case P_0F38:
                        opc = VexOpcode.VEX_OPCODE_0F_38;
                        break;
                    case P_0F3A:
                        opc = VexOpcode.VEX_OPCODE_0F_3A;
                        break;
                    default:
                        opc = VexOpcode.VEX_OPCODE_NONE;
                        break;
                }
                int encode;
                if (noNds) {
                    encode = asm.simdPrefixAndEncode(dst, Register.None, src, pre, opc, attributes);
                } else {
                    encode = asm.simdPrefixAndEncode(dst, dst, src, pre, opc, attributes);
                }
                asm.emitByte(op);
                asm.emitByte(0xC0 | encode);
                emitImmediate(asm, size, imm);
            } else {
                emitOpcode(asm, size, getRXB(dst, src), dst.encoding, src.encoding);
                asm.emitModRM(dst, src);
                emitImmediate(asm, size, imm);
            }
        }

        public final void emit(AMD64Assembler asm, OperandSize size, Register dst, AMD64Address src, int imm) {
            assert verify(asm, size, dst, null);

            boolean isSimd = false;
            boolean noNds = false;

            switch (op) {
                case 0x0A:
                case 0x0B:
                    isSimd = true;
                    noNds = true;
                    break;
            }

            if (isSimd) {
                int pre;
                int opc;
                AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, asm.target);
                int curPrefix = size.sizePrefix | prefix1;
                switch (curPrefix) {
                    case 0x66:
                        pre = VexSimdPrefix.VEX_SIMD_66;
                        break;
                    case 0xF2:
                        pre = VexSimdPrefix.VEX_SIMD_F2;
                        break;
                    case 0xF3:
                        pre = VexSimdPrefix.VEX_SIMD_F3;
                        break;
                    default:
                        pre = VexSimdPrefix.VEX_SIMD_NONE;
                        break;
                }
                switch (prefix2) {
                    case P_0F:
                        opc = VexOpcode.VEX_OPCODE_0F;
                        break;
                    case P_0F38:
                        opc = VexOpcode.VEX_OPCODE_0F_38;
                        break;
                    case P_0F3A:
                        opc = VexOpcode.VEX_OPCODE_0F_3A;
                        break;
                    default:
                        opc = VexOpcode.VEX_OPCODE_NONE;
                        break;
                }

                if (noNds) {
                    asm.simdPrefix(dst, Register.None, src, pre, opc, attributes);
                } else {
                    asm.simdPrefix(dst, dst, src, pre, opc, attributes);
                }
                asm.emitByte(op);
                asm.emitOperandHelper(dst, src, immediateSize(size));
                emitImmediate(asm, size, imm);
            } else {
                emitOpcode(asm, size, getRXB(dst, src), dst.encoding, 0);
                asm.emitOperandHelper(dst, src, immediateSize(size));
                emitImmediate(asm, size, imm);
            }
        }
    }

    public static class SSEOp extends AMD64RMOp {
        // @formatter:off
        public static final SSEOp CVTSI2SS  = new SSEOp("CVTSI2SS",  0xF3, P_0F, 0x2A, OpAssertion.IntToFloatingAssertion);
        public static final SSEOp CVTSI2SD  = new SSEOp("CVTSI2SS",  0xF2, P_0F, 0x2A, OpAssertion.IntToFloatingAssertion);
        public static final SSEOp CVTTSS2SI = new SSEOp("CVTTSS2SI", 0xF3, P_0F, 0x2C, OpAssertion.FloatingToIntAssertion);
        public static final SSEOp CVTTSD2SI = new SSEOp("CVTTSD2SI", 0xF2, P_0F, 0x2C, OpAssertion.FloatingToIntAssertion);
        public static final SSEOp UCOMIS    = new SSEOp("UCOMIS",          P_0F, 0x2E, OpAssertion.PackedFloatingAssertion);
        public static final SSEOp SQRT      = new SSEOp("SQRT",            P_0F, 0x51);
        public static final SSEOp AND       = new SSEOp("AND",             P_0F, 0x54, OpAssertion.PackedFloatingAssertion);
        public static final SSEOp ANDN      = new SSEOp("ANDN",            P_0F, 0x55, OpAssertion.PackedFloatingAssertion);
        public static final SSEOp OR        = new SSEOp("OR",              P_0F, 0x56, OpAssertion.PackedFloatingAssertion);
        public static final SSEOp XOR       = new SSEOp("XOR",             P_0F, 0x57, OpAssertion.PackedFloatingAssertion);
        public static final SSEOp ADD       = new SSEOp("ADD",             P_0F, 0x58);
        public static final SSEOp MUL       = new SSEOp("MUL",             P_0F, 0x59);
        public static final SSEOp CVTSS2SD  = new SSEOp("CVTSS2SD",        P_0F, 0x5A, OpAssertion.SingleAssertion);
        public static final SSEOp CVTSD2SS  = new SSEOp("CVTSD2SS",        P_0F, 0x5A, OpAssertion.DoubleAssertion);
        public static final SSEOp SUB       = new SSEOp("SUB",             P_0F, 0x5C);
        public static final SSEOp MIN       = new SSEOp("MIN",             P_0F, 0x5D);
        public static final SSEOp DIV       = new SSEOp("DIV",             P_0F, 0x5E);
        public static final SSEOp MAX       = new SSEOp("MAX",             P_0F, 0x5F);
        // @formatter:on

        protected SSEOp(String opcode, int prefix, int op) {
            this(opcode, prefix, op, OpAssertion.FloatingAssertion);
        }

        protected SSEOp(String opcode, int prefix, int op, OpAssertion assertion) {
            this(opcode, 0, prefix, op, assertion);
        }

        protected SSEOp(String opcode, int mandatoryPrefix, int prefix, int op, OpAssertion assertion) {
            super(opcode, mandatoryPrefix, prefix, op, assertion, CPUFeature.SSE2);
        }
    }

    public static class AVXOp extends AMD64RRMOp {
        // @formatter:off
        public static final AVXOp AND       = new AVXOp("AND",             P_0F, 0x54, OpAssertion.PackedFloatingAssertion);
        public static final AVXOp ANDN      = new AVXOp("ANDN",            P_0F, 0x55, OpAssertion.PackedFloatingAssertion);
        public static final AVXOp OR        = new AVXOp("OR",              P_0F, 0x56, OpAssertion.PackedFloatingAssertion);
        public static final AVXOp XOR       = new AVXOp("XOR",             P_0F, 0x57, OpAssertion.PackedFloatingAssertion);
        public static final AVXOp ADD       = new AVXOp("ADD",             P_0F, 0x58);
        public static final AVXOp MUL       = new AVXOp("MUL",             P_0F, 0x59);
        public static final AVXOp SUB       = new AVXOp("SUB",             P_0F, 0x5C);
        public static final AVXOp MIN       = new AVXOp("MIN",             P_0F, 0x5D);
        public static final AVXOp DIV       = new AVXOp("DIV",             P_0F, 0x5E);
        public static final AVXOp MAX       = new AVXOp("MAX",             P_0F, 0x5F);
        // @formatter:on

        protected AVXOp(String opcode, int prefix, int op) {
            this(opcode, prefix, op, OpAssertion.FloatingAssertion);
        }

        protected AVXOp(String opcode, int prefix, int op, OpAssertion assertion) {
            this(opcode, 0, prefix, op, assertion);
        }

        protected AVXOp(String opcode, int mandatoryPrefix, int prefix, int op, OpAssertion assertion) {
            super(opcode, mandatoryPrefix, prefix, op, assertion, CPUFeature.AVX);
        }
    }

    
Arithmetic operation with operand order of RM, MR or MI.
/**
     * Arithmetic operation with operand order of RM, MR or MI.
     */
    public static final class AMD64BinaryArithmetic {
        // @formatter:off
        public static final AMD64BinaryArithmetic ADD = new AMD64BinaryArithmetic("ADD", 0);
        public static final AMD64BinaryArithmetic OR  = new AMD64BinaryArithmetic("OR",  1);
        public static final AMD64BinaryArithmetic ADC = new AMD64BinaryArithmetic("ADC", 2);
        public static final AMD64BinaryArithmetic SBB = new AMD64BinaryArithmetic("SBB", 3);
        public static final AMD64BinaryArithmetic AND = new AMD64BinaryArithmetic("AND", 4);
        public static final AMD64BinaryArithmetic SUB = new AMD64BinaryArithmetic("SUB", 5);
        public static final AMD64BinaryArithmetic XOR = new AMD64BinaryArithmetic("XOR", 6);
        public static final AMD64BinaryArithmetic CMP = new AMD64BinaryArithmetic("CMP", 7);
        // @formatter:on

        private final AMD64MIOp byteImmOp;
        private final AMD64MROp byteMrOp;
        private final AMD64RMOp byteRmOp;

        private final AMD64MIOp immOp;
        private final AMD64MIOp immSxOp;
        private final AMD64MROp mrOp;
        private final AMD64RMOp rmOp;

        private AMD64BinaryArithmetic(String opcode, int code) {
            int baseOp = code << 3;

            byteImmOp = new AMD64MIOp(opcode, true, 0, 0x80, code, OpAssertion.ByteAssertion);
            byteMrOp = new AMD64MROp(opcode, 0, baseOp, OpAssertion.ByteAssertion);
            byteRmOp = new AMD64RMOp(opcode, 0, baseOp | 0x02, OpAssertion.ByteAssertion);

            immOp = new AMD64MIOp(opcode, false, 0, 0x81, code, OpAssertion.IntegerAssertion);
            immSxOp = new AMD64MIOp(opcode, true, 0, 0x83, code, OpAssertion.IntegerAssertion);
            mrOp = new AMD64MROp(opcode, 0, baseOp | 0x01, OpAssertion.IntegerAssertion);
            rmOp = new AMD64RMOp(opcode, 0, baseOp | 0x03, OpAssertion.IntegerAssertion);
        }

        public AMD64MIOp getMIOpcode(OperandSize size, boolean sx) {
            if (size == BYTE) {
                return byteImmOp;
            } else if (sx) {
                return immSxOp;
            } else {
                return immOp;
            }
        }

        public AMD64MROp getMROpcode(OperandSize size) {
            if (size == BYTE) {
                return byteMrOp;
            } else {
                return mrOp;
            }
        }

        public AMD64RMOp getRMOpcode(OperandSize size) {
            if (size == BYTE) {
                return byteRmOp;
            } else {
                return rmOp;
            }
        }
    }

    
Shift operation with operand order of M1, MC or MI.
/**
     * Shift operation with operand order of M1, MC or MI.
     */
    public static final class AMD64Shift {
        // @formatter:off
        public static final AMD64Shift ROL = new AMD64Shift("ROL", 0);
        public static final AMD64Shift ROR = new AMD64Shift("ROR", 1);
        public static final AMD64Shift RCL = new AMD64Shift("RCL", 2);
        public static final AMD64Shift RCR = new AMD64Shift("RCR", 3);
        public static final AMD64Shift SHL = new AMD64Shift("SHL", 4);
        public static final AMD64Shift SHR = new AMD64Shift("SHR", 5);
        public static final AMD64Shift SAR = new AMD64Shift("SAR", 7);
        // @formatter:on

        public final AMD64MOp m1Op;
        public final AMD64MOp mcOp;
        public final AMD64MIOp miOp;

        private AMD64Shift(String opcode, int code) {
            m1Op = new AMD64MOp(opcode, 0, 0xD1, code, OpAssertion.IntegerAssertion);
            mcOp = new AMD64MOp(opcode, 0, 0xD3, code, OpAssertion.IntegerAssertion);
            miOp = new AMD64MIOp(opcode, true, 0, 0xC1, code, OpAssertion.IntegerAssertion);
        }
    }

    public final void addl(AMD64Address dst, int imm32) {
        ADD.getMIOpcode(DWORD, isByte(imm32)).emit(this, DWORD, dst, imm32);
    }

    public final void addl(Register dst, int imm32) {
        ADD.getMIOpcode(DWORD, isByte(imm32)).emit(this, DWORD, dst, imm32);
    }

    public final void addl(Register dst, Register src) {
        ADD.rmOp.emit(this, DWORD, dst, src);
    }

    public final void addpd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x58);
        emitByte(0xC0 | encode);
    }

    public final void addpd(Register dst, AMD64Address src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        simdPrefix(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x58);
        emitOperandHelper(dst, src, 0);
    }

    public final void addsd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x58);
        emitByte(0xC0 | encode);
    }

    public final void addsd(Register dst, AMD64Address src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        simdPrefix(dst, dst, src, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x58);
        emitOperandHelper(dst, src, 0);
    }

    private void addrNop4() {
        // 4 bytes: NOP DWORD PTR [EAX+0]
        emitByte(0x0F);
        emitByte(0x1F);
        emitByte(0x40); // emitRm(cbuf, 0x1, EAXEnc, EAXEnc);
        emitByte(0); // 8-bits offset (1 byte)
    }

    private void addrNop5() {
        // 5 bytes: NOP DWORD PTR [EAX+EAX*0+0] 8-bits offset
        emitByte(0x0F);
        emitByte(0x1F);
        emitByte(0x44); // emitRm(cbuf, 0x1, EAXEnc, 0x4);
        emitByte(0x00); // emitRm(cbuf, 0x0, EAXEnc, EAXEnc);
        emitByte(0); // 8-bits offset (1 byte)
    }

    private void addrNop7() {
        // 7 bytes: NOP DWORD PTR [EAX+0] 32-bits offset
        emitByte(0x0F);
        emitByte(0x1F);
        emitByte(0x80); // emitRm(cbuf, 0x2, EAXEnc, EAXEnc);
        emitInt(0); // 32-bits offset (4 bytes)
    }

    private void addrNop8() {
        // 8 bytes: NOP DWORD PTR [EAX+EAX*0+0] 32-bits offset
        emitByte(0x0F);
        emitByte(0x1F);
        emitByte(0x84); // emitRm(cbuf, 0x2, EAXEnc, 0x4);
        emitByte(0x00); // emitRm(cbuf, 0x0, EAXEnc, EAXEnc);
        emitInt(0); // 32-bits offset (4 bytes)
    }

    public final void andl(Register dst, int imm32) {
        AND.getMIOpcode(DWORD, isByte(imm32)).emit(this, DWORD, dst, imm32);
    }

    public final void andl(Register dst, Register src) {
        AND.rmOp.emit(this, DWORD, dst, src);
    }

    public final void andpd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x54);
        emitByte(0xC0 | encode);
    }

    public final void andpd(Register dst, AMD64Address src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        simdPrefix(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x54);
        emitOperandHelper(dst, src, 0);
    }

    public final void bsrl(Register dst, Register src) {
        int encode = prefixAndEncode(dst.encoding(), src.encoding());
        emitByte(0x0F);
        emitByte(0xBD);
        emitByte(0xC0 | encode);
    }

    public final void bswapl(Register reg) {
        int encode = prefixAndEncode(reg.encoding);
        emitByte(0x0F);
        emitByte(0xC8 | encode);
    }

    public final void cdql() {
        emitByte(0x99);
    }

    public final void cmovl(ConditionFlag cc, Register dst, Register src) {
        int encode = prefixAndEncode(dst.encoding, src.encoding);
        emitByte(0x0F);
        emitByte(0x40 | cc.getValue());
        emitByte(0xC0 | encode);
    }

    public final void cmovl(ConditionFlag cc, Register dst, AMD64Address src) {
        prefix(src, dst);
        emitByte(0x0F);
        emitByte(0x40 | cc.getValue());
        emitOperandHelper(dst, src, 0);
    }

    public final void cmpl(Register dst, int imm32) {
        CMP.getMIOpcode(DWORD, isByte(imm32)).emit(this, DWORD, dst, imm32);
    }

    public final void cmpl(Register dst, Register src) {
        CMP.rmOp.emit(this, DWORD, dst, src);
    }

    public final void cmpl(Register dst, AMD64Address src) {
        CMP.rmOp.emit(this, DWORD, dst, src);
    }

    public final void cmpl(AMD64Address dst, int imm32) {
        CMP.getMIOpcode(DWORD, isByte(imm32)).emit(this, DWORD, dst, imm32);
    }

    // The 32-bit cmpxchg compares the value at adr with the contents of X86.rax,
    // and stores reg into adr if so; otherwise, the value at adr is loaded into X86.rax,.
    // The ZF is set if the compared values were equal, and cleared otherwise.
    public final void cmpxchgl(Register reg, AMD64Address adr) { // cmpxchg
        prefix(adr, reg);
        emitByte(0x0F);
        emitByte(0xB1);
        emitOperandHelper(reg, adr, 0);
    }

    public final void cvtsi2sdl(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.CPU);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x2A);
        emitByte(0xC0 | encode);
    }

    public final void cvttsd2sil(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.CPU) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x2C);
        emitByte(0xC0 | encode);
    }

    protected final void decl(AMD64Address dst) {
        prefix(dst);
        emitByte(0xFF);
        emitOperandHelper(1, dst, 0);
    }

    public final void divsd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x5E);
        emitByte(0xC0 | encode);
    }

    public final void hlt() {
        emitByte(0xF4);
    }

    public final void imull(Register dst, Register src, int value) {
        if (isByte(value)) {
            AMD64RMIOp.IMUL_SX.emit(this, DWORD, dst, src, value);
        } else {
            AMD64RMIOp.IMUL.emit(this, DWORD, dst, src, value);
        }
    }

    protected final void incl(AMD64Address dst) {
        prefix(dst);
        emitByte(0xFF);
        emitOperandHelper(0, dst, 0);
    }

    public void jcc(ConditionFlag cc, int jumpTarget, boolean forceDisp32) {
        int shortSize = 2;
        int longSize = 6;
        long disp = jumpTarget - position();
        if (!forceDisp32 && isByte(disp - shortSize)) {
            // 0111 tttn #8-bit disp
            emitByte(0x70 | cc.getValue());
            emitByte((int) ((disp - shortSize) & 0xFF));
        } else {
            // 0000 1111 1000 tttn #32-bit disp
            assert isInt(disp - longSize) : "must be 32bit offset (call4)";
            emitByte(0x0F);
            emitByte(0x80 | cc.getValue());
            emitInt((int) (disp - longSize));
        }
    }

    public final void jcc(ConditionFlag cc, Label l) {
        assert (0 <= cc.getValue()) && (cc.getValue() < 16) : "illegal cc";
        if (l.isBound()) {
            jcc(cc, l.position(), false);
        } else {
            // Note: could eliminate cond. jumps to this jump if condition
            // is the same however, seems to be rather unlikely case.
            // Note: use jccb() if label to be bound is very close to get
            // an 8-bit displacement
            l.addPatchAt(position());
            emitByte(0x0F);
            emitByte(0x80 | cc.getValue());
            emitInt(0);
        }

    }

    public final void jccb(ConditionFlag cc, Label l) {
        if (l.isBound()) {
            int shortSize = 2;
            int entry = l.position();
            assert isByte(entry - (position() + shortSize)) : "Dispacement too large for a short jmp";
            long disp = entry - position();
            // 0111 tttn #8-bit disp
            emitByte(0x70 | cc.getValue());
            emitByte((int) ((disp - shortSize) & 0xFF));
        } else {
            l.addPatchAt(position());
            emitByte(0x70 | cc.getValue());
            emitByte(0);
        }
    }

    public final void jmp(int jumpTarget, boolean forceDisp32) {
        int shortSize = 2;
        int longSize = 5;
        long disp = jumpTarget - position();
        if (!forceDisp32 && isByte(disp - shortSize)) {
            emitByte(0xEB);
            emitByte((int) ((disp - shortSize) & 0xFF));
        } else {
            emitByte(0xE9);
            emitInt((int) (disp - longSize));
        }
    }

    @Override
    public final void jmp(Label l) {
        if (l.isBound()) {
            jmp(l.position(), false);
        } else {
            // By default, forward jumps are always 32-bit displacements, since
            // we can't yet know where the label will be bound. If you're sure that
            // the forward jump will not run beyond 256 bytes, use jmpb to
            // force an 8-bit displacement.

            l.addPatchAt(position());
            emitByte(0xE9);
            emitInt(0);
        }
    }

    public final void jmp(Register entry) {
        int encode = prefixAndEncode(entry.encoding);
        emitByte(0xFF);
        emitByte(0xE0 | encode);
    }

    public final void jmp(AMD64Address adr) {
        prefix(adr);
        emitByte(0xFF);
        emitOperandHelper(rsp, adr, 0);
    }

    public final void jmpb(Label l) {
        if (l.isBound()) {
            int shortSize = 2;
            int entry = l.position();
            assert isByte((entry - position()) + shortSize) : "Dispacement too large for a short jmp";
            long offs = entry - position();
            emitByte(0xEB);
            emitByte((int) ((offs - shortSize) & 0xFF));
        } else {

            l.addPatchAt(position());
            emitByte(0xEB);
            emitByte(0);
        }
    }

    public final void leaq(Register dst, AMD64Address src) {
        prefixq(src, dst);
        emitByte(0x8D);
        emitOperandHelper(dst, src, 0);
    }

    public final void leave() {
        emitByte(0xC9);
    }

    public final void lock() {
        emitByte(0xF0);
    }

    public final void movapd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x28);
        emitByte(0xC0 | encode);
    }

    public final void movaps(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_NONE, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x28);
        emitByte(0xC0 | encode);
    }

    public final void movb(AMD64Address dst, int imm8) {
        prefix(dst);
        emitByte(0xC6);
        emitOperandHelper(0, dst, 1);
        emitByte(imm8);
    }

    public final void movb(AMD64Address dst, Register src) {
        assert src.getRegisterCategory().equals(AMD64.CPU) : "must have byte register";
        prefix(dst, src, true);
        emitByte(0x88);
        emitOperandHelper(src, dst, 0);
    }

    public final void movl(Register dst, int imm32) {
        int encode = prefixAndEncode(dst.encoding);
        emitByte(0xB8 | encode);
        emitInt(imm32);
    }

    public final void movl(Register dst, Register src) {
        int encode = prefixAndEncode(dst.encoding, src.encoding);
        emitByte(0x8B);
        emitByte(0xC0 | encode);
    }

    public final void movl(Register dst, AMD64Address src) {
        prefix(src, dst);
        emitByte(0x8B);
        emitOperandHelper(dst, src, 0);
    }

    public final void movl(AMD64Address dst, int imm32) {
        prefix(dst);
        emitByte(0xC7);
        emitOperandHelper(0, dst, 4);
        emitInt(imm32);
    }

    public final void movl(AMD64Address dst, Register src) {
        prefix(dst, src);
        emitByte(0x89);
        emitOperandHelper(src, dst, 0);
    }

    
New CPUs require use of movsd and movss to avoid partial register stall when loading from memory. But for old Opteron use movlpd instead of movsd. The selection is done in AMD64MacroAssembler.movdbl(Register, AMD64Address) and AMD64MacroAssembler.movflt(Register, Register). /**
     * New CPUs require use of movsd and movss to avoid partial register stall when loading from
     * memory. But for old Opteron use movlpd instead of movsd. The selection is done in
     * {@link AMD64MacroAssembler#movdbl(Register, AMD64Address)} and
     * {@link AMD64MacroAssembler#movflt(Register, Register)}.
     */
    public final void movlpd(Register dst, AMD64Address src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        simdPrefix(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x12);
        emitOperandHelper(dst, src, 0);
    }

    public final void movlhps(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, src, src, VexSimdPrefix.VEX_SIMD_NONE, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x16);
        emitByte(0xC0 | encode);
    }

    public final void movq(Register dst, AMD64Address src) {
        movq(dst, src, false);
    }

    public final void movq(Register dst, AMD64Address src, boolean wide) {
        if (dst.getRegisterCategory().equals(AMD64.XMM)) {
            AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ wide, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
            simdPrefix(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_F3, VexOpcode.VEX_OPCODE_0F, attributes);
            emitByte(0x7E);
            emitOperandHelper(dst, src, wide, 0);
        } else {
            // gpr version of movq
            prefixq(src, dst);
            emitByte(0x8B);
            emitOperandHelper(dst, src, wide, 0);
        }
    }

    public final void movq(Register dst, Register src) {
        int encode = prefixqAndEncode(dst.encoding, src.encoding);
        emitByte(0x8B);
        emitByte(0xC0 | encode);
    }

    public final void movq(AMD64Address dst, Register src) {
        if (src.getRegisterCategory().equals(AMD64.XMM)) {
            AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ true, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
            simdPrefix(src, Register.None, dst, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
            emitByte(0xD6);
            emitOperandHelper(src, dst, 0);
        } else {
            // gpr version of movq
            prefixq(dst, src);
            emitByte(0x89);
            emitOperandHelper(src, dst, 0);
        }
    }

    public final void movsbl(Register dst, AMD64Address src) {
        prefix(src, dst);
        emitByte(0x0F);
        emitByte(0xBE);
        emitOperandHelper(dst, src, 0);
    }

    public final void movsbl(Register dst, Register src) {
        int encode = prefixAndEncode(dst.encoding, false, src.encoding, true);
        emitByte(0x0F);
        emitByte(0xBE);
        emitByte(0xC0 | encode);
    }

    public final void movsbq(Register dst, AMD64Address src) {
        prefixq(src, dst);
        emitByte(0x0F);
        emitByte(0xBE);
        emitOperandHelper(dst, src, 0);
    }

    public final void movsbq(Register dst, Register src) {
        int encode = prefixqAndEncode(dst.encoding, src.encoding);
        emitByte(0x0F);
        emitByte(0xBE);
        emitByte(0xC0 | encode);
    }

    public final void movsd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x10);
        emitByte(0xC0 | encode);
    }

    public final void movsd(Register dst, AMD64Address src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        simdPrefix(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x10);
        emitOperandHelper(dst, src, 0);
    }

    public final void movsd(AMD64Address dst, Register src) {
        assert src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        simdPrefix(src, Register.None, dst, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x11);
        emitOperandHelper(src, dst, 0);
    }

    public final void movss(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_F3, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x10);
        emitByte(0xC0 | encode);
    }

    public final void movss(Register dst, AMD64Address src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        simdPrefix(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_F3, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x10);
        emitOperandHelper(dst, src, 0);
    }

    public final void movss(AMD64Address dst, Register src) {
        assert src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        simdPrefix(src, Register.None, dst, VexSimdPrefix.VEX_SIMD_F3, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x11);
        emitOperandHelper(src, dst, 0);
    }

    public final void mulpd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x59);
        emitByte(0xC0 | encode);
    }

    public final void mulpd(Register dst, AMD64Address src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        simdPrefix(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x59);
        emitOperandHelper(dst, src, 0);
    }

    public final void mulsd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x59);
        emitByte(0xC0 | encode);
    }

    public final void mulsd(Register dst, AMD64Address src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        simdPrefix(dst, dst, src, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x59);
        emitOperandHelper(dst, src, 0);
    }

    public final void mulss(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_F3, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x59);
        emitByte(0xC0 | encode);
    }

    public final void movswl(Register dst, AMD64Address src) {
        prefix(src, dst);
        emitByte(0x0F);
        emitByte(0xBF);
        emitOperandHelper(dst, src, 0);
    }

    public final void movw(AMD64Address dst, int imm16) {
        emitByte(0x66); // switch to 16-bit mode
        prefix(dst);
        emitByte(0xC7);
        emitOperandHelper(0, dst, 2);
        emitShort(imm16);
    }

    public final void movw(AMD64Address dst, Register src) {
        emitByte(0x66);
        prefix(dst, src);
        emitByte(0x89);
        emitOperandHelper(src, dst, 0);
    }

    public final void movzbl(Register dst, AMD64Address src) {
        prefix(src, dst);
        emitByte(0x0F);
        emitByte(0xB6);
        emitOperandHelper(dst, src, 0);
    }

    public final void movzwl(Register dst, AMD64Address src) {
        prefix(src, dst);
        emitByte(0x0F);
        emitByte(0xB7);
        emitOperandHelper(dst, src, 0);
    }

    public final void negl(Register dst) {
        NEG.emit(this, DWORD, dst);
    }

    public final void notl(Register dst) {
        NOT.emit(this, DWORD, dst);
    }

    @Override
    public final void ensureUniquePC() {
        nop();
    }

    public final void nop() {
        nop(1);
    }

    public void nop(int count) {
        int i = count;
        if (UseNormalNop) {
            assert i > 0 : " ";
            // The fancy nops aren't currently recognized by debuggers making it a
            // pain to disassemble code while debugging. If assert are on clearly
            // speed is not an issue so simply use the single byte traditional nop
            // to do alignment.

            for (; i > 0; i--) {
                emitByte(0x90);
            }
            return;
        }

        if (UseAddressNop) {
            //
            // Using multi-bytes nops "0x0F 0x1F [Address]" for AMD.
            // 1: 0x90
            // 2: 0x66 0x90
            // 3: 0x66 0x66 0x90 (don't use "0x0F 0x1F 0x00" - need patching safe padding)
            // 4: 0x0F 0x1F 0x40 0x00
            // 5: 0x0F 0x1F 0x44 0x00 0x00
            // 6: 0x66 0x0F 0x1F 0x44 0x00 0x00
            // 7: 0x0F 0x1F 0x80 0x00 0x00 0x00 0x00
            // 8: 0x0F 0x1F 0x84 0x00 0x00 0x00 0x00 0x00
            // 9: 0x66 0x0F 0x1F 0x84 0x00 0x00 0x00 0x00 0x00
            // 10: 0x66 0x66 0x0F 0x1F 0x84 0x00 0x00 0x00 0x00 0x00
            // 11: 0x66 0x66 0x66 0x0F 0x1F 0x84 0x00 0x00 0x00 0x00 0x00

            // The rest coding is AMD specific - use consecutive Address nops

            // 12: 0x66 0x0F 0x1F 0x44 0x00 0x00 0x66 0x0F 0x1F 0x44 0x00 0x00
            // 13: 0x0F 0x1F 0x80 0x00 0x00 0x00 0x00 0x66 0x0F 0x1F 0x44 0x00 0x00
            // 14: 0x0F 0x1F 0x80 0x00 0x00 0x00 0x00 0x0F 0x1F 0x80 0x00 0x00 0x00 0x00
            // 15: 0x0F 0x1F 0x84 0x00 0x00 0x00 0x00 0x00 0x0F 0x1F 0x80 0x00 0x00 0x00 0x00
            // 16: 0x0F 0x1F 0x84 0x00 0x00 0x00 0x00 0x00 0x0F 0x1F 0x84 0x00 0x00 0x00 0x00 0x00
            // Size prefixes (0x66) are added for larger sizes

            while (i >= 22) {
                i -= 11;
                emitByte(0x66); // size prefix
                emitByte(0x66); // size prefix
                emitByte(0x66); // size prefix
                addrNop8();
            }
            // Generate first nop for size between 21-12
            switch (i) {
                case 21:
                    i -= 11;
                    emitByte(0x66); // size prefix
                    emitByte(0x66); // size prefix
                    emitByte(0x66); // size prefix
                    addrNop8();
                    break;
                case 20:
                case 19:
                    i -= 10;
                    emitByte(0x66); // size prefix
                    emitByte(0x66); // size prefix
                    addrNop8();
                    break;
                case 18:
                case 17:
                    i -= 9;
                    emitByte(0x66); // size prefix
                    addrNop8();
                    break;
                case 16:
                case 15:
                    i -= 8;
                    addrNop8();
                    break;
                case 14:
                case 13:
                    i -= 7;
                    addrNop7();
                    break;
                case 12:
                    i -= 6;
                    emitByte(0x66); // size prefix
                    addrNop5();
                    break;
                default:
                    assert i < 12;
            }

            // Generate second nop for size between 11-1
            switch (i) {
                case 11:
                    emitByte(0x66); // size prefix
                    emitByte(0x66); // size prefix
                    emitByte(0x66); // size prefix
                    addrNop8();
                    break;
                case 10:
                    emitByte(0x66); // size prefix
                    emitByte(0x66); // size prefix
                    addrNop8();
                    break;
                case 9:
                    emitByte(0x66); // size prefix
                    addrNop8();
                    break;
                case 8:
                    addrNop8();
                    break;
                case 7:
                    addrNop7();
                    break;
                case 6:
                    emitByte(0x66); // size prefix
                    addrNop5();
                    break;
                case 5:
                    addrNop5();
                    break;
                case 4:
                    addrNop4();
                    break;
                case 3:
                    // Don't use "0x0F 0x1F 0x00" - need patching safe padding
                    emitByte(0x66); // size prefix
                    emitByte(0x66); // size prefix
                    emitByte(0x90); // nop
                    break;
                case 2:
                    emitByte(0x66); // size prefix
                    emitByte(0x90); // nop
                    break;
                case 1:
                    emitByte(0x90); // nop
                    break;
                default:
                    assert i == 0;
            }
            return;
        }

        // Using nops with size prefixes "0x66 0x90".
        // From AMD Optimization Guide:
        // 1: 0x90
        // 2: 0x66 0x90
        // 3: 0x66 0x66 0x90
        // 4: 0x66 0x66 0x66 0x90
        // 5: 0x66 0x66 0x90 0x66 0x90
        // 6: 0x66 0x66 0x90 0x66 0x66 0x90
        // 7: 0x66 0x66 0x66 0x90 0x66 0x66 0x90
        // 8: 0x66 0x66 0x66 0x90 0x66 0x66 0x66 0x90
        // 9: 0x66 0x66 0x90 0x66 0x66 0x90 0x66 0x66 0x90
        // 10: 0x66 0x66 0x66 0x90 0x66 0x66 0x90 0x66 0x66 0x90
        //
        while (i > 12) {
            i -= 4;
            emitByte(0x66); // size prefix
            emitByte(0x66);
            emitByte(0x66);
            emitByte(0x90); // nop
        }
        // 1 - 12 nops
        if (i > 8) {
            if (i > 9) {
                i -= 1;
                emitByte(0x66);
            }
            i -= 3;
            emitByte(0x66);
            emitByte(0x66);
            emitByte(0x90);
        }
        // 1 - 8 nops
        if (i > 4) {
            if (i > 6) {
                i -= 1;
                emitByte(0x66);
            }
            i -= 3;
            emitByte(0x66);
            emitByte(0x66);
            emitByte(0x90);
        }
        switch (i) {
            case 4:
                emitByte(0x66);
                emitByte(0x66);
                emitByte(0x66);
                emitByte(0x90);
                break;
            case 3:
                emitByte(0x66);
                emitByte(0x66);
                emitByte(0x90);
                break;
            case 2:
                emitByte(0x66);
                emitByte(0x90);
                break;
            case 1:
                emitByte(0x90);
                break;
            default:
                assert i == 0;
        }
    }

    public final void orl(Register dst, Register src) {
        OR.rmOp.emit(this, DWORD, dst, src);
    }

    public final void orl(Register dst, int imm32) {
        OR.getMIOpcode(DWORD, isByte(imm32)).emit(this, DWORD, dst, imm32);
    }

    public final void pop(Register dst) {
        int encode = prefixAndEncode(dst.encoding);
        emitByte(0x58 | encode);
    }

    public void popfq() {
        emitByte(0x9D);
    }

    public final void ptest(Register dst, Register src) {
        assert supports(CPUFeature.SSE4_1);
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F_38, attributes);
        emitByte(0x17);
        emitByte(0xC0 | encode);
    }

    public final void vptest(Register dst, Register src) {
        assert supports(CPUFeature.AVX);
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_256bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = vexPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F_38, attributes);
        emitByte(0x17);
        emitByte(0xC0 | encode);
    }

    public final void push(Register src) {
        int encode = prefixAndEncode(src.encoding);
        emitByte(0x50 | encode);
    }

    public void pushfq() {
        emitByte(0x9c);
    }

    public final void paddd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0xFE);
        emitByte(0xC0 | encode);
    }

    public final void paddq(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0xD4);
        emitByte(0xC0 | encode);
    }

    public final void pextrw(Register dst, Register src, int imm8) {
        assert dst.getRegisterCategory().equals(AMD64.CPU) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0xC5);
        emitByte(0xC0 | encode);
        emitByte(imm8);
    }

    public final void pinsrw(Register dst, Register src, int imm8) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.CPU);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0xC4);
        emitByte(0xC0 | encode);
        emitByte(imm8);
    }

    public final void por(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0xEB);
        emitByte(0xC0 | encode);
    }

    public final void pand(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0xDB);
        emitByte(0xC0 | encode);
    }

    public final void pxor(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0xEF);
        emitByte(0xC0 | encode);
    }

    public final void vpxor(Register dst, Register nds, Register src) {
        assert supports(CPUFeature.AVX);
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_256bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = vexPrefixAndEncode(dst, nds, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0xEF);
        emitByte(0xC0 | encode);
    }

    public final void pslld(Register dst, int imm8) {
        assert isUByte(imm8) : "invalid value";
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        // XMM6 is for /6 encoding: 66 0F 72 /6 ib
        int encode = simdPrefixAndEncode(AMD64.xmm6, dst, dst, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x72);
        emitByte(0xC0 | encode);
        emitByte(imm8 & 0xFF);
    }

    public final void psllq(Register dst, Register shift) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && shift.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, shift, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0xF3);
        emitByte(0xC0 | encode);
    }

    public final void psllq(Register dst, int imm8) {
        assert isUByte(imm8) : "invalid value";
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        // XMM6 is for /6 encoding: 66 0F 73 /6 ib
        int encode = simdPrefixAndEncode(AMD64.xmm6, dst, dst, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x73);
        emitByte(0xC0 | encode);
        emitByte(imm8);
    }

    public final void psrad(Register dst, int imm8) {
        assert isUByte(imm8) : "invalid value";
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        // XMM4 is for /2 encoding: 66 0F 72 /4 ib
        int encode = simdPrefixAndEncode(AMD64.xmm4, dst, dst, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x72);
        emitByte(0xC0 | encode);
        emitByte(imm8);
    }

    public final void psrld(Register dst, int imm8) {
        assert isUByte(imm8) : "invalid value";
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        // XMM2 is for /2 encoding: 66 0F 72 /2 ib
        int encode = simdPrefixAndEncode(AMD64.xmm2, dst, dst, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x72);
        emitByte(0xC0 | encode);
        emitByte(imm8);
    }

    public final void psrlq(Register dst, int imm8) {
        assert isUByte(imm8) : "invalid value";
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        // XMM2 is for /2 encoding: 66 0F 73 /2 ib
        int encode = simdPrefixAndEncode(AMD64.xmm2, dst, dst, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x73);
        emitByte(0xC0 | encode);
        emitByte(imm8);
    }

    public final void pshufd(Register dst, Register src, int imm8) {
        assert isUByte(imm8) : "invalid value";
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x70);
        emitByte(0xC0 | encode);
        emitByte(imm8);
    }

    public final void psubd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0xFA);
        emitByte(0xC0 | encode);
    }

    public final void rcpps(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ true, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_NONE, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x53);
        emitByte(0xC0 | encode);
    }

    public final void ret(int imm16) {
        if (imm16 == 0) {
            emitByte(0xC3);
        } else {
            emitByte(0xC2);
            emitShort(imm16);
        }
    }

    public final void sarl(Register dst, int imm8) {
        int encode = prefixAndEncode(dst.encoding);
        assert isShiftCount(imm8 >> 1) : "illegal shift count";
        if (imm8 == 1) {
            emitByte(0xD1);
            emitByte(0xF8 | encode);
        } else {
            emitByte(0xC1);
            emitByte(0xF8 | encode);
            emitByte(imm8);
        }
    }

    public final void shll(Register dst, int imm8) {
        assert isShiftCount(imm8 >> 1) : "illegal shift count";
        int encode = prefixAndEncode(dst.encoding);
        if (imm8 == 1) {
            emitByte(0xD1);
            emitByte(0xE0 | encode);
        } else {
            emitByte(0xC1);
            emitByte(0xE0 | encode);
            emitByte(imm8);
        }
    }

    public final void shll(Register dst) {
        int encode = prefixAndEncode(dst.encoding);
        emitByte(0xD3);
        emitByte(0xE0 | encode);
    }

    public final void shrl(Register dst, int imm8) {
        assert isShiftCount(imm8 >> 1) : "illegal shift count";
        int encode = prefixAndEncode(dst.encoding);
        emitByte(0xC1);
        emitByte(0xE8 | encode);
        emitByte(imm8);
    }

    public final void shrl(Register dst) {
        int encode = prefixAndEncode(dst.encoding);
        emitByte(0xD3);
        emitByte(0xE8 | encode);
    }

    public final void subl(AMD64Address dst, int imm32) {
        SUB.getMIOpcode(DWORD, isByte(imm32)).emit(this, DWORD, dst, imm32);
    }

    public final void subl(Register dst, int imm32) {
        SUB.getMIOpcode(DWORD, isByte(imm32)).emit(this, DWORD, dst, imm32);
    }

    public final void subl(Register dst, Register src) {
        SUB.rmOp.emit(this, DWORD, dst, src);
    }

    public final void subpd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x5C);
        emitByte(0xC0 | encode);
    }

    public final void subsd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x5C);
        emitByte(0xC0 | encode);
    }

    public final void subsd(Register dst, AMD64Address src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        simdPrefix(dst, dst, src, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x5C);
        emitOperandHelper(dst, src, 0);
    }

    public final void testl(Register dst, int imm32) {
        // not using emitArith because test
        // doesn't support sign-extension of
        // 8bit operands
        int encode = dst.encoding;
        if (encode == 0) {
            emitByte(0xA9);
        } else {
            encode = prefixAndEncode(encode);
            emitByte(0xF7);
            emitByte(0xC0 | encode);
        }
        emitInt(imm32);
    }

    public final void testl(Register dst, Register src) {
        int encode = prefixAndEncode(dst.encoding, src.encoding);
        emitByte(0x85);
        emitByte(0xC0 | encode);
    }

    public final void testl(Register dst, AMD64Address src) {
        prefix(src, dst);
        emitByte(0x85);
        emitOperandHelper(dst, src, 0);
    }

    public final void unpckhpd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x15);
        emitByte(0xC0 | encode);
    }

    public final void unpcklpd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x14);
        emitByte(0xC0 | encode);
    }

    public final void xorl(Register dst, Register src) {
        XOR.rmOp.emit(this, DWORD, dst, src);
    }

    public final void xorpd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x57);
        emitByte(0xC0 | encode);
    }

    public final void xorps(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_NONE, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x57);
        emitByte(0xC0 | encode);
    }

    protected final void decl(Register dst) {
        // Use two-byte form (one-byte form is a REX prefix in 64-bit mode)
        int encode = prefixAndEncode(dst.encoding);
        emitByte(0xFF);
        emitByte(0xC8 | encode);
    }

    protected final void incl(Register dst) {
        // Use two-byte form (one-byte from is a REX prefix in 64-bit mode)
        int encode = prefixAndEncode(dst.encoding);
        emitByte(0xFF);
        emitByte(0xC0 | encode);
    }

    private int prefixAndEncode(int regEnc) {
        return prefixAndEncode(regEnc, false);
    }

    private int prefixAndEncode(int regEnc, boolean byteinst) {
        if (regEnc >= 8) {
            emitByte(Prefix.REXB);
            return regEnc - 8;
        } else if (byteinst && regEnc >= 4) {
            emitByte(Prefix.REX);
        }
        return regEnc;
    }

    private int prefixqAndEncode(int regEnc) {
        if (regEnc < 8) {
            emitByte(Prefix.REXW);
            return regEnc;
        } else {
            emitByte(Prefix.REXWB);
            return regEnc - 8;
        }
    }

    private int prefixAndEncode(int dstEnc, int srcEnc) {
        return prefixAndEncode(dstEnc, false, srcEnc, false);
    }

    private int prefixAndEncode(int dstEncoding, boolean dstIsByte, int srcEncoding, boolean srcIsByte) {
        int srcEnc = srcEncoding;
        int dstEnc = dstEncoding;
        if (dstEnc < 8) {
            if (srcEnc >= 8) {
                emitByte(Prefix.REXB);
                srcEnc -= 8;
            } else if ((srcIsByte && srcEnc >= 4) || (dstIsByte && dstEnc >= 4)) {
                emitByte(Prefix.REX);
            }
        } else {
            if (srcEnc < 8) {
                emitByte(Prefix.REXR);
            } else {
                emitByte(Prefix.REXRB);
                srcEnc -= 8;
            }
            dstEnc -= 8;
        }
        return dstEnc << 3 | srcEnc;
    }

    
Creates prefix and the encoding of the lower 6 bits of the ModRM-Byte. It emits an operand
prefix. If the given operands exceed 3 bits, the 4th bit is encoded in the prefix.
Params:
regEncoding – the encoding of the register part of the ModRM-Byte
rmEncoding – the encoding of the r/m part of the ModRM-Byte
Returns:
the lower 6 bits of the ModRM-Byte that should be emitted/**
     * Creates prefix and the encoding of the lower 6 bits of the ModRM-Byte. It emits an operand
     * prefix. If the given operands exceed 3 bits, the 4th bit is encoded in the prefix.
     *
     * @param regEncoding the encoding of the register part of the ModRM-Byte
     * @param rmEncoding the encoding of the r/m part of the ModRM-Byte
     * @return the lower 6 bits of the ModRM-Byte that should be emitted
     */
    private int prefixqAndEncode(int regEncoding, int rmEncoding) {
        int rmEnc = rmEncoding;
        int regEnc = regEncoding;
        if (regEnc < 8) {
            if (rmEnc < 8) {
                emitByte(Prefix.REXW);
            } else {
                emitByte(Prefix.REXWB);
                rmEnc -= 8;
            }
        } else {
            if (rmEnc < 8) {
                emitByte(Prefix.REXWR);
            } else {
                emitByte(Prefix.REXWRB);
                rmEnc -= 8;
            }
            regEnc -= 8;
        }
        return regEnc << 3 | rmEnc;
    }

    private void vexPrefix(int rxb, int ndsEncoding, int pre, int opc, AMD64InstructionAttr attributes) {
        int vectorLen = attributes.getVectorLen();
        boolean vexW = attributes.isRexVexW();
        boolean isXorB = ((rxb & 0x3) > 0);
        if (isXorB || vexW || (opc == VexOpcode.VEX_OPCODE_0F_38) || (opc == VexOpcode.VEX_OPCODE_0F_3A)) {
            emitByte(Prefix.VEX_3BYTES);

            int byte1 = (rxb << 5);
            byte1 = ((~byte1) & 0xE0) | opc;
            emitByte(byte1);

            int byte2 = ((~ndsEncoding) & 0xf) << 3;
            byte2 |= (vexW ? VexPrefix.VEX_W : 0) | ((vectorLen > 0) ? 4 : 0) | pre;
            emitByte(byte2);
        } else {
            emitByte(Prefix.VEX_2BYTES);

            int byte1 = ((rxb & 0x4) > 0) ? VexPrefix.VEX_R : 0;
            byte1 = (~byte1) & 0x80;
            byte1 |= ((~ndsEncoding) & 0xf) << 3;
            byte1 |= ((vectorLen > 0) ? 4 : 0) | pre;
            emitByte(byte1);
        }
    }

    private void vexPrefix(AMD64Address adr, Register nds, Register src, int pre, int opc, AMD64InstructionAttr attributes) {
        int rxb = getRXB(src, adr);
        int ndsEncoding = nds.isValid() ? nds.encoding : 0;
        vexPrefix(rxb, ndsEncoding, pre, opc, attributes);
        setCurAttributes(attributes);
    }

    private int vexPrefixAndEncode(Register dst, Register nds, Register src, int pre, int opc, AMD64InstructionAttr attributes) {
        int rxb = getRXB(dst, src);
        int ndsEncoding = nds.isValid() ? nds.encoding : 0;
        vexPrefix(rxb, ndsEncoding, pre, opc, attributes);
        // return modrm byte components for operands
        return (((dst.encoding & 7) << 3) | (src.encoding & 7));
    }

    private void simdPrefix(Register xreg, Register nds, AMD64Address adr, int pre, int opc, AMD64InstructionAttr attributes) {
        if (supports(CPUFeature.AVX)) {
            vexPrefix(adr, nds, xreg, pre, opc, attributes);
        } else {
            switch (pre) {
                case VexSimdPrefix.VEX_SIMD_66:
                    emitByte(0x66);
                    break;
                case VexSimdPrefix.VEX_SIMD_F2:
                    emitByte(0xF2);
                    break;
                case VexSimdPrefix.VEX_SIMD_F3:
                    emitByte(0xF3);
                    break;
            }
            if (attributes.isRexVexW()) {
                prefixq(adr, xreg);
            } else {
                prefix(adr, xreg);
            }
            switch (opc) {
                case VexOpcode.VEX_OPCODE_0F:
                    emitByte(0x0F);
                    break;
                case VexOpcode.VEX_OPCODE_0F_38:
                    emitByte(0x0F);
                    emitByte(0x38);
                    break;
                case VexOpcode.VEX_OPCODE_0F_3A:
                    emitByte(0x0F);
                    emitByte(0x3A);
                    break;
            }
        }
    }

    private int simdPrefixAndEncode(Register dst, Register nds, Register src, int pre, int opc, AMD64InstructionAttr attributes) {
        if (supports(CPUFeature.AVX)) {
            return vexPrefixAndEncode(dst, nds, src, pre, opc, attributes);
        } else {
            switch (pre) {
                case VexSimdPrefix.VEX_SIMD_66:
                    emitByte(0x66);
                    break;
                case VexSimdPrefix.VEX_SIMD_F2:
                    emitByte(0xF2);
                    break;
                case VexSimdPrefix.VEX_SIMD_F3:
                    emitByte(0xF3);
                    break;
            }
            int encode;
            int dstEncoding = dst.encoding;
            int srcEncoding = src.encoding;
            if (attributes.isRexVexW()) {
                encode = prefixqAndEncode(dstEncoding, srcEncoding);
            } else {
                encode = prefixAndEncode(dstEncoding, srcEncoding);
            }
            switch (opc) {
                case VexOpcode.VEX_OPCODE_0F:
                    emitByte(0x0F);
                    break;
                case VexOpcode.VEX_OPCODE_0F_38:
                    emitByte(0x0F);
                    emitByte(0x38);
                    break;
                case VexOpcode.VEX_OPCODE_0F_3A:
                    emitByte(0x0F);
                    emitByte(0x3A);
                    break;
            }
            return encode;
        }
    }

    private static boolean needsRex(Register reg) {
        return reg.encoding >= MinEncodingNeedsRex;
    }

    private void prefix(AMD64Address adr) {
        if (needsRex(adr.getBase())) {
            if (needsRex(adr.getIndex())) {
                emitByte(Prefix.REXXB);
            } else {
                emitByte(Prefix.REXB);
            }
        } else {
            if (needsRex(adr.getIndex())) {
                emitByte(Prefix.REXX);
            }
        }
    }

    private void prefixq(AMD64Address adr) {
        if (needsRex(adr.getBase())) {
            if (needsRex(adr.getIndex())) {
                emitByte(Prefix.REXWXB);
            } else {
                emitByte(Prefix.REXWB);
            }
        } else {
            if (needsRex(adr.getIndex())) {
                emitByte(Prefix.REXWX);
            } else {
                emitByte(Prefix.REXW);
            }
        }
    }

    private void prefix(AMD64Address adr, Register reg) {
        prefix(adr, reg, false);
    }

    private void prefix(AMD64Address adr, Register reg, boolean byteinst) {
        if (reg.encoding < 8) {
            if (needsRex(adr.getBase())) {
                if (needsRex(adr.getIndex())) {
                    emitByte(Prefix.REXXB);
                } else {
                    emitByte(Prefix.REXB);
                }
            } else {
                if (needsRex(adr.getIndex())) {
                    emitByte(Prefix.REXX);
                } else if (byteinst && reg.encoding >= 4) {
                    emitByte(Prefix.REX);
                }
            }
        } else {
            if (needsRex(adr.getBase())) {
                if (needsRex(adr.getIndex())) {
                    emitByte(Prefix.REXRXB);
                } else {
                    emitByte(Prefix.REXRB);
                }
            } else {
                if (needsRex(adr.getIndex())) {
                    emitByte(Prefix.REXRX);
                } else {
                    emitByte(Prefix.REXR);
                }
            }
        }
    }

    private void prefixq(AMD64Address adr, Register src) {
        if (src.encoding < 8) {
            if (needsRex(adr.getBase())) {
                if (needsRex(adr.getIndex())) {
                    emitByte(Prefix.REXWXB);
                } else {
                    emitByte(Prefix.REXWB);
                }
            } else {
                if (needsRex(adr.getIndex())) {
                    emitByte(Prefix.REXWX);
                } else {
                    emitByte(Prefix.REXW);
                }
            }
        } else {
            if (needsRex(adr.getBase())) {
                if (needsRex(adr.getIndex())) {
                    emitByte(Prefix.REXWRXB);
                } else {
                    emitByte(Prefix.REXWRB);
                }
            } else {
                if (needsRex(adr.getIndex())) {
                    emitByte(Prefix.REXWRX);
                } else {
                    emitByte(Prefix.REXWR);
                }
            }
        }
    }

    public final void addq(Register dst, int imm32) {
        ADD.getMIOpcode(QWORD, isByte(imm32)).emit(this, QWORD, dst, imm32);
    }

    public final void addq(AMD64Address dst, int imm32) {
        ADD.getMIOpcode(QWORD, isByte(imm32)).emit(this, QWORD, dst, imm32);
    }

    public final void addq(Register dst, Register src) {
        ADD.rmOp.emit(this, QWORD, dst, src);
    }

    public final void addq(AMD64Address dst, Register src) {
        ADD.mrOp.emit(this, QWORD, dst, src);
    }

    public final void andq(Register dst, int imm32) {
        AND.getMIOpcode(QWORD, isByte(imm32)).emit(this, QWORD, dst, imm32);
    }

    public final void bsrq(Register dst, Register src) {
        int encode = prefixqAndEncode(dst.encoding(), src.encoding());
        emitByte(0x0F);
        emitByte(0xBD);
        emitByte(0xC0 | encode);
    }

    public final void bswapq(Register reg) {
        int encode = prefixqAndEncode(reg.encoding);
        emitByte(0x0F);
        emitByte(0xC8 | encode);
    }

    public final void cdqq() {
        emitByte(Prefix.REXW);
        emitByte(0x99);
    }

    public final void cmovq(ConditionFlag cc, Register dst, Register src) {
        int encode = prefixqAndEncode(dst.encoding, src.encoding);
        emitByte(0x0F);
        emitByte(0x40 | cc.getValue());
        emitByte(0xC0 | encode);
    }

    public final void cmovq(ConditionFlag cc, Register dst, AMD64Address src) {
        prefixq(src, dst);
        emitByte(0x0F);
        emitByte(0x40 | cc.getValue());
        emitOperandHelper(dst, src, 0);
    }

    public final void cmpq(Register dst, int imm32) {
        CMP.getMIOpcode(QWORD, isByte(imm32)).emit(this, QWORD, dst, imm32);
    }

    public final void cmpq(Register dst, Register src) {
        CMP.rmOp.emit(this, QWORD, dst, src);
    }

    public final void cmpq(Register dst, AMD64Address src) {
        CMP.rmOp.emit(this, QWORD, dst, src);
    }

    public final void cmpxchgq(Register reg, AMD64Address adr) {
        prefixq(adr, reg);
        emitByte(0x0F);
        emitByte(0xB1);
        emitOperandHelper(reg, adr, 0);
    }

    public final void cvtdq2pd(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_F3, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0xE6);
        emitByte(0xC0 | encode);
    }

    public final void cvtsi2sdq(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.CPU);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ true, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, dst, src, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x2A);
        emitByte(0xC0 | encode);
    }

    public final void cvttsd2siq(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.CPU) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ true, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x2C);
        emitByte(0xC0 | encode);
    }

    public final void cvttpd2dq(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0xE6);
        emitByte(0xC0 | encode);
    }

    protected final void decq(Register dst) {
        // Use two-byte form (one-byte from is a REX prefix in 64-bit mode)
        int encode = prefixqAndEncode(dst.encoding);
        emitByte(0xFF);
        emitByte(0xC8 | encode);
    }

    public final void decq(AMD64Address dst) {
        DEC.emit(this, QWORD, dst);
    }

    public final void imulq(Register dst, Register src) {
        int encode = prefixqAndEncode(dst.encoding, src.encoding);
        emitByte(0x0F);
        emitByte(0xAF);
        emitByte(0xC0 | encode);
    }

    public final void incq(Register dst) {
        // Don't use it directly. Use Macroincrementq() instead.
        // Use two-byte form (one-byte from is a REX prefix in 64-bit mode)
        int encode = prefixqAndEncode(dst.encoding);
        emitByte(0xFF);
        emitByte(0xC0 | encode);
    }

    public final void incq(AMD64Address dst) {
        INC.emit(this, QWORD, dst);
    }

    public final void movq(Register dst, long imm64) {
        int encode = prefixqAndEncode(dst.encoding);
        emitByte(0xB8 | encode);
        emitLong(imm64);
    }

    public final void movslq(Register dst, int imm32) {
        int encode = prefixqAndEncode(dst.encoding);
        emitByte(0xC7);
        emitByte(0xC0 | encode);
        emitInt(imm32);
    }

    public final void movdq(Register dst, AMD64Address src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ true, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        simdPrefix(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x6E);
        emitOperandHelper(dst, src, 0);
    }

    public final void movdq(AMD64Address dst, Register src) {
        assert src.getRegisterCategory().equals(AMD64.XMM);
        // swap src/dst to get correct prefix
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ true, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        simdPrefix(src, Register.None, dst, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x7E);
        emitOperandHelper(src, dst, 0);
    }

    public final void movdq(Register dst, Register src) {
        if (dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.CPU)) {
            AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ true, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
            int encode = simdPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
            emitByte(0x6E);
            emitByte(0xC0 | encode);
        } else if (src.getRegisterCategory().equals(AMD64.XMM) && dst.getRegisterCategory().equals(AMD64.CPU)) {
            // swap src/dst to get correct prefix
            AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ true, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
            int encode = simdPrefixAndEncode(src, Register.None, dst, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
            emitByte(0x7E);
            emitByte(0xC0 | encode);
        } else {
            throw new InternalError("should not reach here");
        }
    }

    public final void movdl(Register dst, Register src) {
        if (dst.getRegisterCategory().equals(AMD64.XMM) && src.getRegisterCategory().equals(AMD64.CPU)) {
            AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
            int encode = simdPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
            emitByte(0x6E);
            emitByte(0xC0 | encode);
        } else if (src.getRegisterCategory().equals(AMD64.XMM) && dst.getRegisterCategory().equals(AMD64.CPU)) {
            // swap src/dst to get correct prefix
            AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
            int encode = simdPrefixAndEncode(src, Register.None, dst, VexSimdPrefix.VEX_SIMD_66, VexOpcode.VEX_OPCODE_0F, attributes);
            emitByte(0x7E);
            emitByte(0xC0 | encode);
        } else {
            throw new InternalError("should not reach here");
        }
    }

    public final void movddup(Register dst, Register src) {
        assert supports(CPUFeature.SSE3);
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_F2, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x12);
        emitByte(0xC0 | encode);
    }

    public final void movdqu(Register dst, AMD64Address src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        simdPrefix(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_F3, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x6F);
        emitOperandHelper(dst, src, 0);
    }

    public final void movdqu(Register dst, Register src) {
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        int encode = simdPrefixAndEncode(dst, Register.None, src, VexSimdPrefix.VEX_SIMD_F3, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x6F);
        emitByte(0xC0 | encode);
    }

    public final void vmovdqu(Register dst, AMD64Address src) {
        assert supports(CPUFeature.AVX);
        assert dst.getRegisterCategory().equals(AMD64.XMM);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_256bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        vexPrefix(src, Register.None, dst, VexSimdPrefix.VEX_SIMD_F3, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x6F);
        emitOperandHelper(dst, src, 0);
    }

    public final void vzeroupper() {
        assert supports(CPUFeature.AVX);
        AMD64InstructionAttr attributes = new AMD64InstructionAttr(AvxVectorLen.AVX_128bit, /* rexVexW */ false, /* legacyMode */ false, /* noMaskReg */ false, /* usesVl */ false, target);
        vexPrefixAndEncode(AMD64.xmm0, AMD64.xmm0, AMD64.xmm0, VexSimdPrefix.VEX_SIMD_NONE, VexOpcode.VEX_OPCODE_0F, attributes);
        emitByte(0x77);
    }

    public final void movslq(AMD64Address dst, int imm32) {
        prefixq(dst);
        emitByte(0xC7);
        emitOperandHelper(0, dst, 4);
        emitInt(imm32);
    }

    public final void movslq(Register dst, AMD64Address src) {
        prefixq(src, dst);
        emitByte(0x63);
        emitOperandHelper(dst, src, 0);
    }

    public final void movslq(Register dst, Register src) {
        int encode = prefixqAndEncode(dst.encoding, src.encoding);
        emitByte(0x63);
        emitByte(0xC0 | encode);
    }

    public final void negq(Register dst) {
        int encode = prefixqAndEncode(dst.encoding);
        emitByte(0xF7);
        emitByte(0xD8 | encode);
    }

    public final void orq(Register dst, Register src) {
        OR.rmOp.emit(this, QWORD, dst, src);
    }

    public final void shlq(Register dst, int imm8) {
        assert isShiftCount(imm8 >> 1) : "illegal shift count";
        int encode = prefixqAndEncode(dst.encoding);
        if (imm8 == 1) {
            emitByte(0xD1);
            emitByte(0xE0 | encode);
        } else {
            emitByte(0xC1);
            emitByte(0xE0 | encode);
            emitByte(imm8);
        }
    }

    public final void shlq(Register dst) {
        int encode = prefixqAndEncode(dst.encoding);
        emitByte(0xD3);
        emitByte(0xE0 | encode);
    }

    public final void shrq(Register dst, int imm8) {
        assert isShiftCount(imm8 >> 1) : "illegal shift count";
        int encode = prefixqAndEncode(dst.encoding);
        if (imm8 == 1) {
            emitByte(0xD1);
            emitByte(0xE8 | encode);
        } else {
            emitByte(0xC1);
            emitByte(0xE8 | encode);
            emitByte(imm8);
        }
    }

    public final void shrq(Register dst) {
        int encode = prefixqAndEncode(dst.encoding);
        emitByte(0xD3);
        emitByte(0xE8 | encode);
    }

    public final void sbbq(Register dst, Register src) {
        SBB.rmOp.emit(this, QWORD, dst, src);
    }

    public final void subq(Register dst, int imm32) {
        SUB.getMIOpcode(QWORD, isByte(imm32)).emit(this, QWORD, dst, imm32);
    }

    public final void subq(AMD64Address dst, int imm32) {
        SUB.getMIOpcode(QWORD, isByte(imm32)).emit(this, QWORD, dst, imm32);
    }

    public final void subqWide(Register dst, int imm32) {
        // don't use the sign-extending version, forcing a 32-bit immediate
        SUB.getMIOpcode(QWORD, false).emit(this, QWORD, dst, imm32);
    }

    public final void subq(Register dst, Register src) {
        SUB.rmOp.emit(this, QWORD, dst, src);
    }

    public final void testq(Register dst, Register src) {
        int encode = prefixqAndEncode(dst.encoding, src.encoding);
        emitByte(0x85);
        emitByte(0xC0 | encode);
    }

    public final void xaddl(AMD64Address dst, Register src) {
        prefix(dst, src);
        emitByte(0x0F);
        emitByte(0xC1);
        emitOperandHelper(src, dst, 0);
    }

    public final void xaddq(AMD64Address dst, Register src) {
        prefixq(dst, src);
        emitByte(0x0F);
        emitByte(0xC1);
        emitOperandHelper(src, dst, 0);
    }

    public final void xchgl(Register dst, AMD64Address src) {
        prefix(src, dst);
        emitByte(0x87);
        emitOperandHelper(dst, src, 0);
    }

    public final void xchgq(Register dst, AMD64Address src) {
        prefixq(src, dst);
        emitByte(0x87);
        emitOperandHelper(dst, src, 0);
    }

    public final void membar(int barriers) {
        if (target.isMP) {
            // We only have to handle StoreLoad
            if ((barriers & STORE_LOAD) != 0) {
                // All usable chips support "locked" instructions which suffice
                // as barriers, and are much faster than the alternative of
                // using cpuid instruction. We use here a locked add [rsp],0.
                // This is conveniently otherwise a no-op except for blowing
                // flags.
                // Any change to this code may need to revisit other places in
                // the code where this idiom is used, in particular the
                // orderAccess code.
                lock();
                addl(new AMD64Address(rsp, 0), 0); // Assert the lock# signal here
            }
        }
    }

    @Override
    protected final void patchJumpTarget(int branch, int branchTarget) {
        int op = getByte(branch);
        assert op == 0xE8 // call
                        ||
                        op == 0x00 // jump table entry
                        || op == 0xE9 // jmp
                        || op == 0xEB // short jmp
                        || (op & 0xF0) == 0x70 // short jcc
                        || op == 0x0F && (getByte(branch + 1) & 0xF0) == 0x80 // jcc
        : "Invalid opcode at patch point branch=" + branch + ", branchTarget=" + branchTarget + ", op=" + op;

        if (op == 0x00) {
            int offsetToJumpTableBase = getShort(branch + 1);
            int jumpTableBase = branch - offsetToJumpTableBase;
            int imm32 = branchTarget - jumpTableBase;
            emitInt(imm32, branch);
        } else if (op == 0xEB || (op & 0xF0) == 0x70) {

            // short offset operators (jmp and jcc)
            final int imm8 = branchTarget - (branch + 2);
            /*
             * Since a wrongly patched short branch can potentially lead to working but really bad
             * behaving code we should always fail with an exception instead of having an assert.
             */
            if (!NumUtil.isByte(imm8)) {
                throw new InternalError("branch displacement out of range: " + imm8);
            }
            emitByte(imm8, branch + 1);

        } else {

            int off = 1;
            if (op == 0x0F) {
                off = 2;
            }

            int imm32 = branchTarget - (branch + 4 + off);
            emitInt(imm32, branch + off);
        }
    }

    public void nullCheck(AMD64Address address) {
        testl(AMD64.rax, address);
    }

    @Override
    public void align(int modulus) {
        if (position() % modulus != 0) {
            nop(modulus - (position() % modulus));
        }
    }

    
Emits a direct call instruction. Note that the actual call target is not specified, because
all calls need patching anyway. Therefore, 0 is emitted as the call target, and the user is
responsible to add the call address to the appropriate patching tables.
/**
     * Emits a direct call instruction. Note that the actual call target is not specified, because
     * all calls need patching anyway. Therefore, 0 is emitted as the call target, and the user is
     * responsible to add the call address to the appropriate patching tables.
     */
    public final void call() {
        if (codePatchingAnnotationConsumer != null) {
            int pos = position();
            codePatchingAnnotationConsumer.accept(new ImmediateOperandAnnotation(pos, pos + 1, 4, pos + 5));
        }
        emitByte(0xE8);
        emitInt(0);
    }

    public final void call(Register src) {
        int encode = prefixAndEncode(src.encoding);
        emitByte(0xFF);
        emitByte(0xD0 | encode);
    }

    public final void int3() {
        emitByte(0xCC);
    }

    public final void pause() {
        emitByte(0xF3);
        emitByte(0x90);
    }

    private void emitx87(int b1, int b2, int i) {
        assert 0 <= i && i < 8 : "illegal stack offset";
        emitByte(b1);
        emitByte(b2 + i);
    }

    public final void fldd(AMD64Address src) {
        emitByte(0xDD);
        emitOperandHelper(0, src, 0);
    }

    public final void flds(AMD64Address src) {
        emitByte(0xD9);
        emitOperandHelper(0, src, 0);
    }

    public final void fldln2() {
        emitByte(0xD9);
        emitByte(0xED);
    }

    public final void fldlg2() {
        emitByte(0xD9);
        emitByte(0xEC);
    }

    public final void fyl2x() {
        emitByte(0xD9);
        emitByte(0xF1);
    }

    public final void fstps(AMD64Address src) {
        emitByte(0xD9);
        emitOperandHelper(3, src, 0);
    }

    public final void fstpd(AMD64Address src) {
        emitByte(0xDD);
        emitOperandHelper(3, src, 0);
    }

    private void emitFPUArith(int b1, int b2, int i) {
        assert 0 <= i && i < 8 : "illegal FPU register: " + i;
        emitByte(b1);
        emitByte(b2 + i);
    }

    public void ffree(int i) {
        emitFPUArith(0xDD, 0xC0, i);
    }

    public void fincstp() {
        emitByte(0xD9);
        emitByte(0xF7);
    }

    public void fxch(int i) {
        emitFPUArith(0xD9, 0xC8, i);
    }

    public void fnstswAX() {
        emitByte(0xDF);
        emitByte(0xE0);
    }

    public void fwait() {
        emitByte(0x9B);
    }

    public void fprem() {
        emitByte(0xD9);
        emitByte(0xF8);
    }

    public final void fsin() {
        emitByte(0xD9);
        emitByte(0xFE);
    }

    public final void fcos() {
        emitByte(0xD9);
        emitByte(0xFF);
    }

    public final void fptan() {
        emitByte(0xD9);
        emitByte(0xF2);
    }

    public final void fstp(int i) {
        emitx87(0xDD, 0xD8, i);
    }

    @Override
    public AMD64Address makeAddress(Register base, int displacement) {
        return new AMD64Address(base, displacement);
    }

    @Override
    public AMD64Address getPlaceholder(int instructionStartPosition) {
        return new AMD64Address(rip, Register.None, Scale.Times1, 0, instructionStartPosition);
    }

    private void prefetchPrefix(AMD64Address src) {
        prefix(src);
        emitByte(0x0F);
    }

    public void prefetchnta(AMD64Address src) {
        prefetchPrefix(src);
        emitByte(0x18);
        emitOperandHelper(0, src, 0);
    }

    void prefetchr(AMD64Address src) {
        assert supports(CPUFeature.AMD_3DNOW_PREFETCH);
        prefetchPrefix(src);
        emitByte(0x0D);
        emitOperandHelper(0, src, 0);
    }

    public void prefetcht0(AMD64Address src) {
        assert supports(CPUFeature.SSE);
        prefetchPrefix(src);
        emitByte(0x18);
        emitOperandHelper(1, src, 0);
    }

    public void prefetcht1(AMD64Address src) {
        assert supports(CPUFeature.SSE);
        prefetchPrefix(src);
        emitByte(0x18);
        emitOperandHelper(2, src, 0);
    }

    public void prefetcht2(AMD64Address src) {
        assert supports(CPUFeature.SSE);
        prefix(src);
        emitByte(0x0f);
        emitByte(0x18);
        emitOperandHelper(3, src, 0);
    }

    public void prefetchw(AMD64Address src) {
        assert supports(CPUFeature.AMD_3DNOW_PREFETCH);
        prefix(src);
        emitByte(0x0f);
        emitByte(0x0D);
        emitOperandHelper(1, src, 0);
    }

    public void rdtsc() {
        emitByte(0x0F);
        emitByte(0x31);
    }

    
Emits an instruction which is considered to be illegal. This is used if we deliberately want
to crash the program (debugging etc.).
/**
     * Emits an instruction which is considered to be illegal. This is used if we deliberately want
     * to crash the program (debugging etc.).
     */
    public void illegal() {
        emitByte(0x0f);
        emitByte(0x0b);
    }
}