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//===- X86InstrFormats.td - X86 Instruction Formats --------*- tablegen -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//===----------------------------------------------------------------------===//
// X86 Instruction Format Definitions.
//
// Format specifies the encoding used by the instruction. This is part of the
// ad-hoc solution used to emit machine instruction encodings by our machine
// code emitter.
class Format<bits<6> val> {
bits<6> Value = val;
}
def Pseudo : Format<0>; def RawFrm : Format<1>;
def AddRegFrm : Format<2>; def MRMDestReg : Format<3>;
def MRMDestMem : Format<4>; def MRMSrcReg : Format<5>;
def MRMSrcMem : Format<6>;
def MRM0r : Format<16>; def MRM1r : Format<17>; def MRM2r : Format<18>;
def MRM3r : Format<19>; def MRM4r : Format<20>; def MRM5r : Format<21>;
def MRM6r : Format<22>; def MRM7r : Format<23>;
def MRM0m : Format<24>; def MRM1m : Format<25>; def MRM2m : Format<26>;
def MRM3m : Format<27>; def MRM4m : Format<28>; def MRM5m : Format<29>;
def MRM6m : Format<30>; def MRM7m : Format<31>;
def MRMInitReg : Format<32>;
def MRM_C1 : Format<33>;
def MRM_C2 : Format<34>;
def MRM_C3 : Format<35>;
def MRM_C4 : Format<36>;
def MRM_C8 : Format<37>;
def MRM_C9 : Format<38>;
def MRM_E8 : Format<39>;
def MRM_F0 : Format<40>;
def MRM_F8 : Format<41>;
def MRM_F9 : Format<42>;
def RawFrmImm8 : Format<43>;
def RawFrmImm16 : Format<44>;
def MRM_D0 : Format<45>;
def MRM_D1 : Format<46>;
// ImmType - This specifies the immediate type used by an instruction. This is
// part of the ad-hoc solution used to emit machine instruction encodings by our
// machine code emitter.
class ImmType<bits<3> val> {
bits<3> Value = val;
}
def NoImm : ImmType<0>;
def Imm8 : ImmType<1>;
def Imm8PCRel : ImmType<2>;
def Imm16 : ImmType<3>;
def Imm16PCRel : ImmType<4>;
def Imm32 : ImmType<5>;
def Imm32PCRel : ImmType<6>;
def Imm64 : ImmType<7>;
// FPFormat - This specifies what form this FP instruction has. This is used by
// the Floating-Point stackifier pass.
class FPFormat<bits<3> val> {
bits<3> Value = val;
}
def NotFP : FPFormat<0>;
def ZeroArgFP : FPFormat<1>;
def OneArgFP : FPFormat<2>;
def OneArgFPRW : FPFormat<3>;
def TwoArgFP : FPFormat<4>;
def CompareFP : FPFormat<5>;
def CondMovFP : FPFormat<6>;
def SpecialFP : FPFormat<7>;
// Class specifying the SSE execution domain, used by the SSEDomainFix pass.
// Keep in sync with tables in X86InstrInfo.cpp.
class Domain<bits<2> val> {
bits<2> Value = val;
}
def GenericDomain : Domain<0>;
def SSEPackedSingle : Domain<1>;
def SSEPackedDouble : Domain<2>;
def SSEPackedInt : Domain<3>;
// Prefix byte classes which are used to indicate to the ad-hoc machine code
// emitter that various prefix bytes are required.
class OpSize { bit hasOpSizePrefix = 1; }
class AdSize { bit hasAdSizePrefix = 1; }
class REX_W { bit hasREX_WPrefix = 1; }
class LOCK { bit hasLockPrefix = 1; }
class SegFS { bits<2> SegOvrBits = 1; }
class SegGS { bits<2> SegOvrBits = 2; }
class TB { bits<4> Prefix = 1; }
class REP { bits<4> Prefix = 2; }
class D8 { bits<4> Prefix = 3; }
class D9 { bits<4> Prefix = 4; }
class DA { bits<4> Prefix = 5; }
class DB { bits<4> Prefix = 6; }
class DC { bits<4> Prefix = 7; }
class DD { bits<4> Prefix = 8; }
class DE { bits<4> Prefix = 9; }
class DF { bits<4> Prefix = 10; }
class XD { bits<4> Prefix = 11; }
class XS { bits<4> Prefix = 12; }
class T8 { bits<4> Prefix = 13; }
class TA { bits<4> Prefix = 14; }
class TF { bits<4> Prefix = 15; }
class VEX { bit hasVEXPrefix = 1; }
class VEX_W { bit hasVEX_WPrefix = 1; }
class VEX_4V : VEX { bit hasVEX_4VPrefix = 1; }
class VEX_I8IMM { bit hasVEX_i8ImmReg = 1; }
class VEX_L { bit hasVEX_L = 1; }
class Has3DNow0F0FOpcode { bit has3DNow0F0FOpcode = 1; }
class X86Inst<bits<8> opcod, Format f, ImmType i, dag outs, dag ins,
string AsmStr, Domain d = GenericDomain>
: Instruction {
let Namespace = "X86";
bits<8> Opcode = opcod;
Format Form = f;
bits<6> FormBits = Form.Value;
ImmType ImmT = i;
dag OutOperandList = outs;
dag InOperandList = ins;
string AsmString = AsmStr;
// If this is a pseudo instruction, mark it isCodeGenOnly.
let isCodeGenOnly = !eq(!cast<string>(f), "Pseudo");
//
// Attributes specific to X86 instructions...
//
bit hasOpSizePrefix = 0; // Does this inst have a 0x66 prefix?
bit hasAdSizePrefix = 0; // Does this inst have a 0x67 prefix?
bits<4> Prefix = 0; // Which prefix byte does this inst have?
bit hasREX_WPrefix = 0; // Does this inst require the REX.W prefix?
FPFormat FPForm = NotFP; // What flavor of FP instruction is this?
bit hasLockPrefix = 0; // Does this inst have a 0xF0 prefix?
bits<2> SegOvrBits = 0; // Segment override prefix.
Domain ExeDomain = d;
bit hasVEXPrefix = 0; // Does this inst require a VEX prefix?
bit hasVEX_WPrefix = 0; // Does this inst set the VEX_W field?
bit hasVEX_4VPrefix = 0; // Does this inst require the VEX.VVVV field?
bit hasVEX_i8ImmReg = 0; // Does this inst require the last source register
// to be encoded in a immediate field?
bit hasVEX_L = 0; // Does this inst use large (256-bit) registers?
bit has3DNow0F0FOpcode =0;// Wacky 3dNow! encoding?
// TSFlags layout should be kept in sync with X86InstrInfo.h.
let TSFlags{5-0} = FormBits;
let TSFlags{6} = hasOpSizePrefix;
let TSFlags{7} = hasAdSizePrefix;
let TSFlags{11-8} = Prefix;
let TSFlags{12} = hasREX_WPrefix;
let TSFlags{15-13} = ImmT.Value;
let TSFlags{18-16} = FPForm.Value;
let TSFlags{19} = hasLockPrefix;
let TSFlags{21-20} = SegOvrBits;
let TSFlags{23-22} = ExeDomain.Value;
let TSFlags{31-24} = Opcode;
let TSFlags{32} = hasVEXPrefix;
let TSFlags{33} = hasVEX_WPrefix;
let TSFlags{34} = hasVEX_4VPrefix;
let TSFlags{35} = hasVEX_i8ImmReg;
let TSFlags{36} = hasVEX_L;
let TSFlags{37} = has3DNow0F0FOpcode;
}
class PseudoI<dag oops, dag iops, list<dag> pattern>
: X86Inst<0, Pseudo, NoImm, oops, iops, ""> {
let Pattern = pattern;
}
class I<bits<8> o, Format f, dag outs, dag ins, string asm,
list<dag> pattern, Domain d = GenericDomain>
: X86Inst<o, f, NoImm, outs, ins, asm, d> {
let Pattern = pattern;
let CodeSize = 3;
}
class Ii8 <bits<8> o, Format f, dag outs, dag ins, string asm,
list<dag> pattern, Domain d = GenericDomain>
: X86Inst<o, f, Imm8, outs, ins, asm, d> {
let Pattern = pattern;
let CodeSize = 3;
}
class Ii8PCRel<bits<8> o, Format f, dag outs, dag ins, string asm,
list<dag> pattern>
: X86Inst<o, f, Imm8PCRel, outs, ins, asm> {
let Pattern = pattern;
let CodeSize = 3;
}
class Ii16<bits<8> o, Format f, dag outs, dag ins, string asm,
list<dag> pattern>
: X86Inst<o, f, Imm16, outs, ins, asm> {
let Pattern = pattern;
let CodeSize = 3;
}
class Ii32<bits<8> o, Format f, dag outs, dag ins, string asm,
list<dag> pattern>
: X86Inst<o, f, Imm32, outs, ins, asm> {
let Pattern = pattern;
let CodeSize = 3;
}
class Ii16PCRel<bits<8> o, Format f, dag outs, dag ins, string asm,
list<dag> pattern>
: X86Inst<o, f, Imm16PCRel, outs, ins, asm> {
let Pattern = pattern;
let CodeSize = 3;
}
class Ii32PCRel<bits<8> o, Format f, dag outs, dag ins, string asm,
list<dag> pattern>
: X86Inst<o, f, Imm32PCRel, outs, ins, asm> {
let Pattern = pattern;
let CodeSize = 3;
}
// FPStack Instruction Templates:
// FPI - Floating Point Instruction template.
class FPI<bits<8> o, Format F, dag outs, dag ins, string asm>
: I<o, F, outs, ins, asm, []> {}
// FpI_ - Floating Point Pseudo Instruction template. Not Predicated.
class FpI_<dag outs, dag ins, FPFormat fp, list<dag> pattern>
: X86Inst<0, Pseudo, NoImm, outs, ins, ""> {
let FPForm = fp;
let Pattern = pattern;
}
// Templates for instructions that use a 16- or 32-bit segmented address as
// their only operand: lcall (FAR CALL) and ljmp (FAR JMP)
//
// Iseg16 - 16-bit segment selector, 16-bit offset
// Iseg32 - 16-bit segment selector, 32-bit offset
class Iseg16 <bits<8> o, Format f, dag outs, dag ins, string asm,
list<dag> pattern> : X86Inst<o, f, Imm16, outs, ins, asm> {
let Pattern = pattern;
let CodeSize = 3;
}
class Iseg32 <bits<8> o, Format f, dag outs, dag ins, string asm,
list<dag> pattern> : X86Inst<o, f, Imm32, outs, ins, asm> {
let Pattern = pattern;
let CodeSize = 3;
}
// SI - SSE 1 & 2 scalar instructions
class SI<bits<8> o, Format F, dag outs, dag ins, string asm, list<dag> pattern>
: I<o, F, outs, ins, asm, pattern> {
let Predicates = !if(hasVEXPrefix /* VEX */, [HasAVX],
!if(!eq(Prefix, 12 /* XS */), [HasSSE1], [HasSSE2]));
// AVX instructions have a 'v' prefix in the mnemonic
let AsmString = !if(hasVEXPrefix, !strconcat("v", asm), asm);
}
// SIi8 - SSE 1 & 2 scalar instructions
class SIi8<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern> {
let Predicates = !if(hasVEXPrefix /* VEX */, [HasAVX],
!if(!eq(Prefix, 12 /* XS */), [HasSSE1], [HasSSE2]));
// AVX instructions have a 'v' prefix in the mnemonic
let AsmString = !if(hasVEXPrefix, !strconcat("v", asm), asm);
}
// PI - SSE 1 & 2 packed instructions
class PI<bits<8> o, Format F, dag outs, dag ins, string asm, list<dag> pattern,
Domain d>
: I<o, F, outs, ins, asm, pattern, d> {
let Predicates = !if(hasVEXPrefix /* VEX */, [HasAVX],
!if(hasOpSizePrefix /* OpSize */, [HasSSE2], [HasSSE1]));
// AVX instructions have a 'v' prefix in the mnemonic
let AsmString = !if(hasVEXPrefix, !strconcat("v", asm), asm);
}
// PIi8 - SSE 1 & 2 packed instructions with immediate
class PIi8<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern, Domain d>
: Ii8<o, F, outs, ins, asm, pattern, d> {
let Predicates = !if(hasVEX_4VPrefix /* VEX */, [HasAVX],
!if(hasOpSizePrefix /* OpSize */, [HasSSE2], [HasSSE1]));
// AVX instructions have a 'v' prefix in the mnemonic
let AsmString = !if(hasVEX_4VPrefix, !strconcat("v", asm), asm);
}
// SSE1 Instruction Templates:
//
// SSI - SSE1 instructions with XS prefix.
// PSI - SSE1 instructions with TB prefix.
// PSIi8 - SSE1 instructions with ImmT == Imm8 and TB prefix.
// VSSI - SSE1 instructions with XS prefix in AVX form.
// VPSI - SSE1 instructions with TB prefix in AVX form.
class SSI<bits<8> o, Format F, dag outs, dag ins, string asm, list<dag> pattern>
: I<o, F, outs, ins, asm, pattern>, XS, Requires<[HasSSE1]>;
class SSIi8<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern>, XS, Requires<[HasSSE1]>;
class PSI<bits<8> o, Format F, dag outs, dag ins, string asm, list<dag> pattern>
: I<o, F, outs, ins, asm, pattern, SSEPackedSingle>, TB,
Requires<[HasSSE1]>;
class PSIi8<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern, SSEPackedSingle>, TB,
Requires<[HasSSE1]>;
class VSSI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: I<o, F, outs, ins, !strconcat("v", asm), pattern>, XS,
Requires<[HasAVX]>;
class VPSI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: I<o, F, outs, ins, !strconcat("v", asm), pattern, SSEPackedSingle>,
Requires<[HasAVX]>;
// SSE2 Instruction Templates:
//
// SDI - SSE2 instructions with XD prefix.
// SDIi8 - SSE2 instructions with ImmT == Imm8 and XD prefix.
// SSDIi8 - SSE2 instructions with ImmT == Imm8 and XS prefix.
// PDI - SSE2 instructions with TB and OpSize prefixes.
// PDIi8 - SSE2 instructions with ImmT == Imm8 and TB and OpSize prefixes.
// VSDI - SSE2 instructions with XD prefix in AVX form.
// VPDI - SSE2 instructions with TB and OpSize prefixes in AVX form.
class SDI<bits<8> o, Format F, dag outs, dag ins, string asm, list<dag> pattern>
: I<o, F, outs, ins, asm, pattern>, XD, Requires<[HasSSE2]>;
class SDIi8<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern>, XD, Requires<[HasSSE2]>;
class SSDIi8<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern>, XS, Requires<[HasSSE2]>;
class PDI<bits<8> o, Format F, dag outs, dag ins, string asm, list<dag> pattern>
: I<o, F, outs, ins, asm, pattern, SSEPackedDouble>, TB, OpSize,
Requires<[HasSSE2]>;
class PDIi8<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern, SSEPackedDouble>, TB, OpSize,
Requires<[HasSSE2]>;
class VSDI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: I<o, F, outs, ins, !strconcat("v", asm), pattern>, XD,
Requires<[HasAVX]>;
class VPDI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: I<o, F, outs, ins, !strconcat("v", asm), pattern, SSEPackedDouble>,
OpSize, Requires<[HasAVX]>;
// SSE3 Instruction Templates:
//
// S3I - SSE3 instructions with TB and OpSize prefixes.
// S3SI - SSE3 instructions with XS prefix.
// S3DI - SSE3 instructions with XD prefix.
class S3SI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: I<o, F, outs, ins, asm, pattern, SSEPackedSingle>, XS,
Requires<[HasSSE3]>;
class S3DI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: I<o, F, outs, ins, asm, pattern, SSEPackedDouble>, XD,
Requires<[HasSSE3]>;
class S3I<bits<8> o, Format F, dag outs, dag ins, string asm, list<dag> pattern>
: I<o, F, outs, ins, asm, pattern, SSEPackedDouble>, TB, OpSize,
Requires<[HasSSE3]>;
// SSSE3 Instruction Templates:
//
// SS38I - SSSE3 instructions with T8 prefix.
// SS3AI - SSSE3 instructions with TA prefix.
//
// Note: SSSE3 instructions have 64-bit and 128-bit versions. The 64-bit version
// uses the MMX registers. We put those instructions here because they better
// fit into the SSSE3 instruction category rather than the MMX category.
class SS38I<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern, SSEPackedInt>, T8,
Requires<[HasSSSE3]>;
class SS3AI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern, SSEPackedInt>, TA,
Requires<[HasSSSE3]>;
// SSE4.1 Instruction Templates:
//
// SS48I - SSE 4.1 instructions with T8 prefix.
// SS41AIi8 - SSE 4.1 instructions with TA prefix and ImmT == Imm8.
//
class SS48I<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: I<o, F, outs, ins, asm, pattern, SSEPackedInt>, T8,
Requires<[HasSSE41]>;
class SS4AIi8<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern, SSEPackedInt>, TA,
Requires<[HasSSE41]>;
// SSE4.2 Instruction Templates:
//
// SS428I - SSE 4.2 instructions with T8 prefix.
class SS428I<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: I<o, F, outs, ins, asm, pattern, SSEPackedInt>, T8,
Requires<[HasSSE42]>;
// SS42FI - SSE 4.2 instructions with TF prefix.
class SS42FI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: I<o, F, outs, ins, asm, pattern>, TF, Requires<[HasSSE42]>;
// SS42AI = SSE 4.2 instructions with TA prefix
class SS42AI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern, SSEPackedInt>, TA,
Requires<[HasSSE42]>;
// AVX Instruction Templates:
// Instructions introduced in AVX (no SSE equivalent forms)
//
// AVX8I - AVX instructions with T8 and OpSize prefix.
// AVXAIi8 - AVX instructions with TA, OpSize prefix and ImmT = Imm8.
class AVX8I<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: I<o, F, outs, ins, asm, pattern, SSEPackedInt>, T8, OpSize,
Requires<[HasAVX]>;
class AVXAIi8<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern, SSEPackedInt>, TA, OpSize,
Requires<[HasAVX]>;
// AES Instruction Templates:
//
// AES8I
// These use the same encoding as the SSE4.2 T8 and TA encodings.
class AES8I<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag>pattern>
: I<o, F, outs, ins, asm, pattern, SSEPackedInt>, T8,
Requires<[HasAES]>;
class AESAI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern, SSEPackedInt>, TA,
Requires<[HasAES]>;
// CLMUL Instruction Templates
class CLMULIi8<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag>pattern>
: Ii8<o, F, outs, ins, asm, pattern, SSEPackedInt>, TA,
OpSize, VEX_4V, Requires<[HasAVX, HasCLMUL]>;
// FMA3 Instruction Templates
class FMA3<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag>pattern>
: I<o, F, outs, ins, asm, pattern, SSEPackedInt>, T8,
OpSize, VEX_4V, Requires<[HasFMA3]>;
// X86-64 Instruction templates...
//
class RI<bits<8> o, Format F, dag outs, dag ins, string asm, list<dag> pattern>
: I<o, F, outs, ins, asm, pattern>, REX_W;
class RIi8 <bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern>, REX_W;
class RIi32 <bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii32<o, F, outs, ins, asm, pattern>, REX_W;
class RIi64<bits<8> o, Format f, dag outs, dag ins, string asm,
list<dag> pattern>
: X86Inst<o, f, Imm64, outs, ins, asm>, REX_W {
let Pattern = pattern;
let CodeSize = 3;
}
class RSSI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: SSI<o, F, outs, ins, asm, pattern>, REX_W;
class RSDI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: SDI<o, F, outs, ins, asm, pattern>, REX_W;
class RPDI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: PDI<o, F, outs, ins, asm, pattern>, REX_W;
// MMX Instruction templates
//
// MMXI - MMX instructions with TB prefix.
// MMXI64 - MMX instructions with TB prefix valid only in 64 bit mode.
// MMX2I - MMX / SSE2 instructions with TB and OpSize prefixes.
// MMXIi8 - MMX instructions with ImmT == Imm8 and TB prefix.
// MMXIi8 - MMX instructions with ImmT == Imm8 and TB prefix.
// MMXID - MMX instructions with XD prefix.
// MMXIS - MMX instructions with XS prefix.
class MMXI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: I<o, F, outs, ins, asm, pattern>, TB, Requires<[HasMMX]>;
class MMXI64<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: I<o, F, outs, ins, asm, pattern>, TB, Requires<[HasMMX,In64BitMode]>;
class MMXRI<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: I<o, F, outs, ins, asm, pattern>, TB, REX_W, Requires<[HasMMX]>;
class MMX2I<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: I<o, F, outs, ins, asm, pattern>, TB, OpSize, Requires<[HasMMX]>;
class MMXIi8<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern>, TB, Requires<[HasMMX]>;
class MMXID<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern>, XD, Requires<[HasMMX]>;
class MMXIS<bits<8> o, Format F, dag outs, dag ins, string asm,
list<dag> pattern>
: Ii8<o, F, outs, ins, asm, pattern>, XS, Requires<[HasMMX]>;