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// Copyright (c) 2007-2008 The Hewlett-Packard Development Company
// All rights reserved.
//
// The license below extends only to copyright in the software and shall
// not be construed as granting a license to any other intellectual
// property including but not limited to intellectual property relating
// to a hardware implementation of the functionality of the software
// licensed hereunder.  You may use the software subject to the license
// terms below provided that you ensure that this notice is replicated
// unmodified and in its entirety in all distributions of the software,
// modified or unmodified, in source code or in binary form.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met: redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer;
// redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution;
// neither the name of the copyright holders nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Authors: Gabe Black

////////////////////////////////////////////////////////////////////
//
// Decode the one byte opcodes
//

'X86ISA::OneByteOpcode': decode OPCODE_OP_TOP5 {
    format Inst {
        0x00: decode OPCODE_OP_BOTTOM3 {
            0x6: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::push_ES();
            }
            0x7: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::pop_ES();
            }
            default: MultiInst::ADD(OPCODE_OP_BOTTOM3,
                                    [Eb,Gb], [Ev,Gv],
                                    [Gb,Eb], [Gv,Ev],
                                    [rAb,Ib], [rAv,Iz]);
        }
        0x01: decode OPCODE_OP_BOTTOM3 {
            0x6: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::push_CS();
            }
            //Any time this is seen, it should generate a two byte opcode
            0x7: M5InternalError::error(
                {{"Saw a one byte opcode whose value was 0x0F!"}});
            default: MultiInst::OR(OPCODE_OP_BOTTOM3,
                                   [Eb,Gb], [Ev,Gv],
                                   [Gb,Eb], [Gv,Ev],
                                   [rAb,Ib], [rAv,Iz]);
        }
        0x02: decode OPCODE_OP_BOTTOM3 {
            0x6: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::push_SS();
            }
            0x7: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::pop_SS();
            }
            default: MultiInst::ADC(OPCODE_OP_BOTTOM3,
                                    [Eb,Gb], [Ev,Gv],
                                    [Gb,Eb], [Gv,Ev],
                                    [rAb,Ib], [rAv,Iz]);
        }
        0x03: decode OPCODE_OP_BOTTOM3 {
            0x6: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::push_DS();
            }
            0x7: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::pop_DS();
            }
            default: MultiInst::SBB(OPCODE_OP_BOTTOM3,
                                    [Eb,Gb], [Ev,Gv],
                                    [Gb,Eb], [Gv,Ev],
                                    [rAb,Ib], [rAv,Iz]);
        }
        0x04: decode OPCODE_OP_BOTTOM3 {
            0x6: M5InternalError::error(
                {{"Tried to execute the ES segment override prefix!"}});
            0x7: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::daa();
            }
            default: MultiInst::AND(OPCODE_OP_BOTTOM3,
                                    [Eb,Gb], [Ev,Gv],
                                    [Gb,Eb], [Gv,Ev],
                                    [rAb,Ib], [rAv,Iz]);
        }
        0x05: decode OPCODE_OP_BOTTOM3 {
            0x6: M5InternalError::error(
                {{"Tried to execute the CS segment override prefix!"}});
            0x7: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::das();
            }
            default: MultiInst::SUB(OPCODE_OP_BOTTOM3,
                                    [Eb,Gb], [Ev,Gv],
                                    [Gb,Eb], [Gv,Ev],
                                    [rAb,Ib], [rAv,Iz]);
        }
        0x06: decode OPCODE_OP_BOTTOM3 {
            0x6: M5InternalError::error(
                {{"Tried to execute the SS segment override prefix!"}});
            0x7: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::aaa();
            }
            default: MultiInst::XOR(OPCODE_OP_BOTTOM3,
                                    [Eb,Gb], [Ev,Gv],
                                    [Gb,Eb], [Gv,Ev],
                                    [rAb,Ib], [rAv,Iz]);
        }
        0x07: decode OPCODE_OP_BOTTOM3 {
            0x6: M5InternalError::error(
                {{"Tried to execute the DS segment override prefix!"}});
            0x7: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::aas();
            }
            default: MultiInst::CMP(OPCODE_OP_BOTTOM3,
                                    [Eb,Gb], [Ev,Gv],
                                    [Gb,Eb], [Gv,Ev],
                                    [rAb,Ib], [rAv,Iz]);
        }
        0x08: decode MODE_SUBMODE {
            0x0: M5InternalError::error (
                {{"Tried to execute an REX prefix!"}});
            default: INC(Bv);
        }
        0x09: decode MODE_SUBMODE {
            0x0: M5InternalError::error (
                {{"Tried to execute an REX prefix!"}});
            default: DEC(Bv);
        }
        0x0A: PUSH(Bv);
        0x0B: POP(Bv);
        0x0C: decode OPCODE_OP_BOTTOM3 {
            0x0: decode MODE_SUBMODE {
                0x0: UD2();
                default: PUSHA();
            }
            0x1: decode MODE_SUBMODE {
                0x0: UD2();
                default: POPA();
            }
            0x2: decode MODE_SUBMODE {
                0x0: UD2();
                default: BOUND(Gv,Mv);
            }
            0x3: decode MODE_SUBMODE {
                //The second operand should really be of size "d", but it's
                //set to "v" in order to have a consistent register size.
                //This shouldn't affect behavior.
                0x0: MOVSXD(Gv,Ev);
                default: WarnUnimpl::arpl_Ew_Gw();
            }
            0x4: M5InternalError::error(
                {{"Tried to execute the FS segment override prefix!"}});
            0x5: M5InternalError::error(
                {{"Tried to execute the GS segment override prefix!"}});
            0x6: M5InternalError::error(
                {{"Tried to execute the operand size override prefix!"}});
            0x7: M5InternalError::error(
                {{"Tried to execute the DS address size override prefix!"}});
        }
        0x0D: decode OPCODE_OP_BOTTOM3 {
            0x0: PUSH(Iz);
            0x1: IMUL(Gv,Ev,Iz);
            0x2: PUSH(Ib);
            0x3: IMUL(Gv,Ev,Ib);
            0x4: StringInst::INS(Yb,rD);
            0x5: StringInst::INS(Yz,rD);
            0x6: StringInst::OUTS(rD,Xb);
            0x7: StringInst::OUTS(rD,Xz);
        }
        0x0E: decode OPCODE_OP_BOTTOM3 {
            0x0: JO(Jb);
            0x1: JNO(Jb);
            0x2: JB(Jb);
            0x3: JNB(Jb);
            0x4: JZ(Jb);
            0x5: JNZ(Jb);
            0x6: JBE(Jb);
            0x7: JNBE(Jb);
        }
        0x0F: decode OPCODE_OP_BOTTOM3 {
            0x0: JS(Jb);
            0x1: JNS(Jb);
            0x2: JP(Jb);
            0x3: JNP(Jb);
            0x4: JL(Jb);
            0x5: JNL(Jb);
            0x6: JLE(Jb);
            0x7: JNLE(Jb);
        }
        0x10: decode OPCODE_OP_BOTTOM3 {
            //0x0: group1_Eb_Ib();
            0x0: decode MODRM_REG {
                0x0: ADD(Eb,Ib);
                0x1: OR(Eb,Ib);
                0x2: ADC(Eb,Ib);
                0x3: SBB(Eb,Ib);
                0x4: AND(Eb,Ib);
                0x5: SUB(Eb,Ib);
                0x6: XOR(Eb,Ib);
                0x7: CMP(Eb,Ib);
            }
            //0x1: group1_Ev_Iz();
            0x1: decode MODRM_REG {
                0x0: ADD(Ev,Iz);
                0x1: OR(Ev,Iz);
                0x2: ADC(Ev,Iz);
                0x3: SBB(Ev,Iz);
                0x4: AND(Ev,Iz);
                0x5: SUB(Ev,Iz);
                0x6: XOR(Ev,Iz);
                0x7: CMP(Ev,Iz);
            }
            0x2: decode MODE_SUBMODE {
                0x0: UD2();
                //default: group1_Eb_Ib();
                default: decode MODRM_REG {
                    0x0: ADD(Eb,Ib);
                    0x1: OR(Eb,Ib);
                    0x2: ADC(Eb,Ib);
                    0x3: SBB(Eb,Ib);
                    0x4: AND(Eb,Ib);
                    0x5: SUB(Eb,Ib);
                    0x6: XOR(Eb,Ib);
                    0x7: CMP(Eb,Ib);
                }
            }
            //0x3: group1_Ev_Ib();
            0x3: decode MODRM_REG {
                0x0: ADD(Ev,Ib);
                0x1: OR(Ev,Ib);
                0x2: ADC(Ev,Ib);
                0x3: SBB(Ev,Ib);
                0x4: AND(Ev,Ib);
                0x5: SUB(Ev,Ib);
                0x6: XOR(Ev,Ib);
                0x7: CMP(Ev,Ib);
            }
            0x4: TEST(Eb,Gb);
            0x5: TEST(Ev,Gv);
            0x6: XCHG(Eb,Gb);
            0x7: XCHG(Ev,Gv);
        }
        0x11: decode OPCODE_OP_BOTTOM3 {
            0x0: MOV(Eb,Gb);
            0x1: MOV(Ev,Gv);
            0x2: MOV(Gb,Eb);
            0x3: MOV(Gv,Ev);
            0x4: decode MODRM_REG {
                0x0, 0x1, 0x2,
                0x3, 0x4, 0x5: MOV(Ev,Sv);
            }
            0x5: LEA(Gv,M);
            0x6: decode MODE_SUBMODE {
                0x3, 0x4: MOV_REAL(Sv,Ev);
                default: decode MODRM_REG {
                    0x1: UD2(); // Moving to the CS selector is illegal.
                    0x2: MOVSS(Sv,Ev);
                    0x0, 0x3,
                    0x4, 0x5: MOV(Sv,Ev);
                    default: UD2();
                }
            }
            //0x7: group10_Ev();
            0x7: decode MODRM_REG {
                0x0: POP(Ev);
                default: UD2();
            }
        }
        0x12: decode OPCODE_OP_BOTTOM3 {
            0x0: NopInst::NOP(); //XXX repe makes this a "pause"
            default: XCHG(Bv,rAv);
        }
        0x13: decode OPCODE_OP_BOTTOM3 {
            0x0: CDQE(rAv);
            0x1: CQO(rAv,rDv);
            0x2: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::call_far_Ap();
            }
            0x3: WarnUnimpl::fwait(); //aka wait
            0x4: PUSHF();
            0x5: POPF();
            //The 64 bit versions of both of these should be illegal only
            //if CPUID says it isn't supported. For now, we'll just assume
            //that it's supported.
            0x6: SAHF();
            0x7: LAHF();
        }
        0x14: decode OPCODE_OP_BOTTOM3 {
            0x0: MOV(rAb, Ob);
            0x1: MOV(rAv, Ov);
            0x2: MOV(Ob, rAb);
            0x3: MOV(Ov, rAv);
            0x4: StringInst::MOVS(Yb,Xb);
            0x5: StringInst::MOVS(Yv,Xv);
            0x6: StringTestInst::CMPS(Yb,Xb);
            0x7: StringTestInst::CMPS(Yv,Xv);
        }
        0x15: decode OPCODE_OP_BOTTOM3 {
            0x0: TEST(rAb,Ib);
            0x1: TEST(rAv,Iz);
            0x2: StringInst::STOS(Yb);
            0x3: StringInst::STOS(Yv);
            0x4: StringInst::LODS(Xb);
            0x5: StringInst::LODS(Xv);
            0x6: StringTestInst::SCAS(Yb);
            0x7: StringTestInst::SCAS(Yv);
        }
        0x16: MOV(Bb,Ib);
        0x17: MOV(Bv,Iv);
        0x18: decode OPCODE_OP_BOTTOM3 {
            //0x0: group2_Eb_Ib();
            0x0: decode MODRM_REG {
                0x0: ROL(Eb,Ib);
                0x1: ROR(Eb,Ib);
                0x2: RCL(Eb,Ib);
                0x3: RCR(Eb,Ib);
                0x4: SAL(Eb,Ib);
                0x5: SHR(Eb,Ib);
                0x6: SAL(Eb,Ib);
                0x7: SAR(Eb,Ib);
            }
            //0x1: group2_Ev_Ib();
            0x1: decode MODRM_REG {
                0x0: ROL(Ev,Ib);
                0x1: ROR(Ev,Ib);
                0x2: RCL(Ev,Ib);
                0x3: RCR(Ev,Ib);
                0x4: SAL(Ev,Ib);
                0x5: SHR(Ev,Ib);
                0x6: SAL(Ev,Ib);
                0x7: SAR(Ev,Ib);
            }
            0x2: RET_NEAR(Iw);
            0x3: RET_NEAR();
            0x4: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::les_Gz_Mp();
            }
            0x5: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::lds_Gz_Mp();
            }
            //0x6: group12_Eb_Ib();
            0x6: decode MODRM_REG {
                0x0: MOV(Eb,Ib);
                default: UD2();
            }
            //0x7: group12_Ev_Iz();
            0x7: decode MODRM_REG {
                0x0: MOV(Ev,Iz);
                default: UD2();
            }
        }
        format WarnUnimpl {
            0x19: decode OPCODE_OP_BOTTOM3 {
                // The second parameter here should be of size b, but
                // immediate sizes are determined elsewhere and this would
                // confuse the instruction type specialization code.
                0x0: Inst::ENTER(Iw,Iw);
                0x1: Inst::LEAVE();
                0x2: ret_far_Iw();
                0x3: decode MODE_SUBMODE {
                    0x3, 0x4: ret_far_real();
                    default: Inst::RET_FAR();
                }
                0x4: Inst::INT3();
                0x5: decode FullSystemInt default inst_ib() {
                    0: decode IMMEDIATE {
                        // Really only the LSB matters, but the decoder
                        // will sign extend it, and there's no easy way to
                        // specify only checking the first byte.
                        0xffffffffffffff80:
                            SyscallInst::int80('xc->syscall(Rax)',
                                 IsSyscall, IsNonSpeculative, IsSerializeAfter);
                    }

                    default: Inst::INT(Ib);
                }
                0x6: decode MODE_SUBMODE {
                    0x0: Inst::UD2();
                    default: into();
                }
                0x7: decode MODE_SUBMODE {
                    0x4: Inst::IRET_REAL();
                    0x3: Inst::IRET_VIRT();
                    default: Inst::IRET_PROT();
                }
            }
        }
        0x1A: decode OPCODE_OP_BOTTOM3 {
            //0x0: group2_Eb_1();
            0x0: decode MODRM_REG {
                0x0: ROL_1(Eb);
                0x1: ROR_1(Eb);
                0x2: RCL_1(Eb);
                0x3: RCR_1(Eb);
                0x4: SAL_1(Eb);
                0x5: SHR_1(Eb);
                0x6: SAL_1(Eb);
                0x7: SAR_1(Eb);
            }
            //0x1: group2_Ev_1();
            0x1: decode MODRM_REG {
                0x0: ROL_1(Ev);
                0x1: ROR_1(Ev);
                0x2: RCL_1(Ev);
                0x3: RCR_1(Ev);
                0x4: SAL_1(Ev);
                0x5: SHR_1(Ev);
                0x6: SAL_1(Ev);
                0x7: SAR_1(Ev);
            }
            //0x2: group2_Eb_Cl();
            0x2: decode MODRM_REG {
                0x0: ROL(Eb,rCb);
                0x1: ROR(Eb,rCb);
                0x2: RCL(Eb,rCb);
                0x3: RCR(Eb,rCb);
                0x4: SAL(Eb,rCb);
                0x5: SHR(Eb,rCb);
                0x6: SAL(Eb,rCb);
                0x7: SAR(Eb,rCb);
            }
            //The second operand should have size "b", but to have
            //consistent register sizes it's "v". This shouldn't have
            //any affect on functionality.
            //0x3: group2_Ev_Cl();
            0x3: decode MODRM_REG {
                0x0: ROL(Ev,rCv);
                0x1: ROR(Ev,rCv);
                0x2: RCL(Ev,rCv);
                0x3: RCR(Ev,rCv);
                0x4: SAL(Ev,rCv);
                0x5: SHR(Ev,rCv);
                0x6: SAL(Ev,rCv);
                0x7: SAR(Ev,rCv);
            }
            0x4: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::aam_Ib();
            }
            0x5: decode MODE_SUBMODE {
                0x0: UD2();
                default: WarnUnimpl::aad_Ib();
            }
            0x6: decode MODE_SUBMODE {
                0x0: UD2();
                default: SALC(rAb);
            }
            0x7: XLAT();
        }
        ##include "x87.isa"
        0x1C: decode OPCODE_OP_BOTTOM3 {
            0x0: LOOPNE(Jb);
            0x1: LOOPE(Jb);
            0x2: LOOP(Jb);
            0x3: JRCX(Jb);
            0x4: IN(rAb,Ib);
            0x5: IN(rAv,Iv);
            0x6: OUT(Ib,rAb);
            0x7: OUT(Iv,rAv);
        }
        0x1D: decode OPCODE_OP_BOTTOM3 {
            0x0: CALL_NEAR(Jz);
            0x1: JMP(Jz);
            0x2: decode MODE_SUBMODE {
                0x0: UD2();
                0x1: JMP_FAR(Iz);
                0x2: JMP_FAR(Iz);
                0x3: JMP_FAR_REAL(Iz);
                0x4: JMP_FAR_REAL(Iz);
            }
            0x3: JMP(Jb);
            0x4: IN(rAb,rD);
            0x5: IN(rAv,rD);
            0x6: OUT(rD,rAb);
            0x7: OUT(rD,rAv);
        }
        0x1E: decode OPCODE_OP_BOTTOM3 {
            0x0: M5InternalError::error(
                {{"Tried to execute the lock prefix!"}});
            0x1: WarnUnimpl::int1();
            0x2: M5InternalError::error(
                {{"Tried to execute the repne prefix!"}});
            0x3: M5InternalError::error(
                {{"Tried to execute the rep/repe prefix!"}});
            0x4: HLT();
            0x5: CMC();
            //0x6: group3_Eb();
            0x6: decode MODRM_REG {
                0x0: TEST(Eb,Iz);
                0x1: TEST(Eb,Iz);
                0x2: NOT(Eb);
                0x3: NEG(Eb);
                0x4: MUL_B(Eb);
                0x5: IMUL_B(Eb);
                //This should be Eb, but it access the entire word value ax.
                0x6: DIV_B(Ew);
                0x7: IDIV_B(Eb);
            }
            //0x7: group3_Ev();
            0x7: decode MODRM_REG {
                0x0: TEST(Ev,Iz);
                0x1: TEST(Ev,Iz);
                0x2: NOT(Ev);
                0x3: NEG(Ev);
                0x4: MUL(Ev);
                0x5: IMUL(Ev);
                0x6: DIV(Ev);
                0x7: IDIV(Ev);
            }
        }
        0x1F: decode OPCODE_OP_BOTTOM3 {
            0x0: CLC();
            0x1: STC();
            0x2: CLI();
            0x3: STI();
            0x4: CLD();
            0x5: STD();
            //0x6: group4();
            0x6: decode MODRM_REG {
                0x0: INC(Eb);
                0x1: DEC(Eb);
                default: UD2();
            }
            //0x7: group5();
            0x7: decode MODRM_REG {
                0x0: INC(Ev);
                0x1: DEC(Ev);
                0x2: CALL_NEAR(Ev);
                0x3: WarnUnimpl::call_far_Mp();
                0x4: JMP(Ev);
                0x5: decode MODE_SUBMODE {
                    0x0: JMP_FAR(Mz);
                    0x1: JMP_FAR(Mz);
                    0x2: JMP_FAR(Mz);
                    0x3: JMP_FAR_REAL(Mz);
                    0x4: JMP_FAR_REAL(Mz);
                }
                0x6: PUSH(Ev);
                0x7: UD2();
            }
        }
    }
    default: FailUnimpl::oneByteOps();
}