forked from OSchip/llvm-project
725 lines
25 KiB
C++
725 lines
25 KiB
C++
//===-- Target.cpp ----------------------------------------------*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#include "../Target.h"
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#include "../Error.h"
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#include "../Latency.h"
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#include "../SnippetGenerator.h"
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#include "../Uops.h"
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#include "MCTargetDesc/X86BaseInfo.h"
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#include "MCTargetDesc/X86MCTargetDesc.h"
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#include "X86.h"
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#include "X86RegisterInfo.h"
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#include "X86Subtarget.h"
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#include "llvm/MC/MCInstBuilder.h"
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#include "llvm/Support/FormatVariadic.h"
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namespace llvm {
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namespace exegesis {
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// Returns an error if we cannot handle the memory references in this
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// instruction.
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static Error isInvalidMemoryInstr(const Instruction &Instr) {
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switch (Instr.Description->TSFlags & X86II::FormMask) {
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default:
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llvm_unreachable("Unknown FormMask value");
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// These have no memory access.
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case X86II::Pseudo:
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case X86II::RawFrm:
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case X86II::AddCCFrm:
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case X86II::MRMDestReg:
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case X86II::MRMSrcReg:
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case X86II::MRMSrcReg4VOp3:
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case X86II::MRMSrcRegOp4:
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case X86II::MRMSrcRegCC:
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case X86II::MRMXrCC:
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case X86II::MRMXr:
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case X86II::MRM0r:
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case X86II::MRM1r:
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case X86II::MRM2r:
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case X86II::MRM3r:
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case X86II::MRM4r:
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case X86II::MRM5r:
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case X86II::MRM6r:
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case X86II::MRM7r:
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case X86II::MRM_C0:
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case X86II::MRM_C1:
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case X86II::MRM_C2:
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case X86II::MRM_C3:
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case X86II::MRM_C4:
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case X86II::MRM_C5:
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case X86II::MRM_C6:
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case X86II::MRM_C7:
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case X86II::MRM_C8:
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case X86II::MRM_C9:
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case X86II::MRM_CA:
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case X86II::MRM_CB:
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case X86II::MRM_CC:
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case X86II::MRM_CD:
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case X86II::MRM_CE:
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case X86II::MRM_CF:
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case X86II::MRM_D0:
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case X86II::MRM_D1:
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case X86II::MRM_D2:
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case X86II::MRM_D3:
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case X86II::MRM_D4:
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case X86II::MRM_D5:
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case X86II::MRM_D6:
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case X86II::MRM_D7:
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case X86II::MRM_D8:
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case X86II::MRM_D9:
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case X86II::MRM_DA:
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case X86II::MRM_DB:
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case X86II::MRM_DC:
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case X86II::MRM_DD:
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case X86II::MRM_DE:
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case X86II::MRM_DF:
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case X86II::MRM_E0:
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case X86II::MRM_E1:
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case X86II::MRM_E2:
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case X86II::MRM_E3:
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case X86II::MRM_E4:
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case X86II::MRM_E5:
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case X86II::MRM_E6:
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case X86II::MRM_E7:
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case X86II::MRM_E8:
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case X86II::MRM_E9:
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case X86II::MRM_EA:
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case X86II::MRM_EB:
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case X86II::MRM_EC:
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case X86II::MRM_ED:
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case X86II::MRM_EE:
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case X86II::MRM_EF:
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case X86II::MRM_F0:
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case X86II::MRM_F1:
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case X86II::MRM_F2:
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case X86II::MRM_F3:
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case X86II::MRM_F4:
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case X86II::MRM_F5:
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case X86II::MRM_F6:
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case X86II::MRM_F7:
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case X86II::MRM_F8:
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case X86II::MRM_F9:
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case X86II::MRM_FA:
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case X86II::MRM_FB:
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case X86II::MRM_FC:
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case X86II::MRM_FD:
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case X86II::MRM_FE:
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case X86II::MRM_FF:
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case X86II::RawFrmImm8:
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return Error::success();
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case X86II::AddRegFrm:
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return (Instr.Description->Opcode == X86::POP16r ||
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Instr.Description->Opcode == X86::POP32r ||
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Instr.Description->Opcode == X86::PUSH16r ||
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Instr.Description->Opcode == X86::PUSH32r)
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? make_error<Failure>(
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"unsupported opcode: unsupported memory access")
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: Error::success();
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// These access memory and are handled.
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case X86II::MRMDestMem:
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case X86II::MRMSrcMem:
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case X86II::MRMSrcMem4VOp3:
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case X86II::MRMSrcMemOp4:
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case X86II::MRMSrcMemCC:
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case X86II::MRMXmCC:
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case X86II::MRMXm:
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case X86II::MRM0m:
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case X86II::MRM1m:
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case X86II::MRM2m:
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case X86II::MRM3m:
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case X86II::MRM4m:
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case X86II::MRM5m:
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case X86II::MRM6m:
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case X86II::MRM7m:
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return Error::success();
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// These access memory and are not handled yet.
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case X86II::RawFrmImm16:
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case X86II::RawFrmMemOffs:
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case X86II::RawFrmSrc:
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case X86II::RawFrmDst:
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case X86II::RawFrmDstSrc:
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return make_error<Failure>("unsupported opcode: non uniform memory access");
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}
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}
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static llvm::Error IsInvalidOpcode(const Instruction &Instr) {
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const auto OpcodeName = Instr.Name;
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if ((Instr.Description->TSFlags & X86II::FormMask) == X86II::Pseudo)
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return llvm::make_error<Failure>("unsupported opcode: pseudo instruction");
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if (OpcodeName.startswith("POPF") || OpcodeName.startswith("PUSHF") ||
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OpcodeName.startswith("ADJCALLSTACK"))
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return llvm::make_error<Failure>(
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"unsupported opcode: Push/Pop/AdjCallStack");
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if (llvm::Error Error = isInvalidMemoryInstr(Instr))
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return Error;
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// We do not handle instructions with OPERAND_PCREL.
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for (const Operand &Op : Instr.Operands)
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if (Op.isExplicit() &&
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Op.getExplicitOperandInfo().OperandType == llvm::MCOI::OPERAND_PCREL)
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return llvm::make_error<Failure>(
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"unsupported opcode: PC relative operand");
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// We do not handle second-form X87 instructions. We only handle first-form
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// ones (_Fp), see comment in X86InstrFPStack.td.
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for (const Operand &Op : Instr.Operands)
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if (Op.isReg() && Op.isExplicit() &&
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Op.getExplicitOperandInfo().RegClass == llvm::X86::RSTRegClassID)
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return llvm::make_error<Failure>(
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"unsupported second-form X87 instruction");
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return llvm::Error::success();
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}
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static unsigned getX86FPFlags(const Instruction &Instr) {
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return Instr.Description->TSFlags & llvm::X86II::FPTypeMask;
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}
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// Helper to fill a memory operand with a value.
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static void setMemOp(InstructionTemplate &IT, int OpIdx,
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const MCOperand &OpVal) {
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const auto Op = IT.Instr.Operands[OpIdx];
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assert(Op.isExplicit() && "invalid memory pattern");
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IT.getValueFor(Op) = OpVal;
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};
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// Common (latency, uops) code for LEA templates. `GetDestReg` takes the
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// addressing base and index registers and returns the LEA destination register.
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static llvm::Expected<std::vector<CodeTemplate>> generateLEATemplatesCommon(
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const Instruction &Instr, const BitVector &ForbiddenRegisters,
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const LLVMState &State, const SnippetGenerator::Options &Opts,
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std::function<unsigned(unsigned, unsigned)> GetDestReg) {
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assert(Instr.Operands.size() == 6 && "invalid LEA");
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assert(X86II::getMemoryOperandNo(Instr.Description->TSFlags) == 1 &&
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"invalid LEA");
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constexpr const int kDestOp = 0;
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constexpr const int kBaseOp = 1;
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constexpr const int kIndexOp = 3;
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auto PossibleDestRegs =
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Instr.Operands[kDestOp].getRegisterAliasing().sourceBits();
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remove(PossibleDestRegs, ForbiddenRegisters);
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auto PossibleBaseRegs =
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Instr.Operands[kBaseOp].getRegisterAliasing().sourceBits();
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remove(PossibleBaseRegs, ForbiddenRegisters);
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auto PossibleIndexRegs =
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Instr.Operands[kIndexOp].getRegisterAliasing().sourceBits();
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remove(PossibleIndexRegs, ForbiddenRegisters);
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const auto &RegInfo = State.getRegInfo();
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std::vector<CodeTemplate> Result;
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for (const unsigned BaseReg : PossibleBaseRegs.set_bits()) {
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for (const unsigned IndexReg : PossibleIndexRegs.set_bits()) {
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for (int LogScale = 0; LogScale <= 3; ++LogScale) {
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// FIXME: Add an option for controlling how we explore immediates.
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for (const int Disp : {0, 42}) {
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InstructionTemplate IT(Instr);
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const int64_t Scale = 1ull << LogScale;
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setMemOp(IT, 1, MCOperand::createReg(BaseReg));
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setMemOp(IT, 2, MCOperand::createImm(Scale));
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setMemOp(IT, 3, MCOperand::createReg(IndexReg));
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setMemOp(IT, 4, MCOperand::createImm(Disp));
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// SegmentReg must be 0 for LEA.
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setMemOp(IT, 5, MCOperand::createReg(0));
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// Output reg is selected by the caller.
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setMemOp(IT, 0, MCOperand::createReg(GetDestReg(BaseReg, IndexReg)));
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CodeTemplate CT;
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CT.Instructions.push_back(std::move(IT));
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CT.Config = formatv("{3}(%{0}, %{1}, {2})", RegInfo.getName(BaseReg),
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RegInfo.getName(IndexReg), Scale, Disp)
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.str();
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Result.push_back(std::move(CT));
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if (Result.size() >= Opts.MaxConfigsPerOpcode)
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return Result;
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}
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}
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}
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}
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return Result;
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}
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namespace {
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class X86LatencySnippetGenerator : public LatencySnippetGenerator {
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public:
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using LatencySnippetGenerator::LatencySnippetGenerator;
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llvm::Expected<std::vector<CodeTemplate>>
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generateCodeTemplates(const Instruction &Instr,
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const BitVector &ForbiddenRegisters) const override;
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};
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} // namespace
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llvm::Expected<std::vector<CodeTemplate>>
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X86LatencySnippetGenerator::generateCodeTemplates(
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const Instruction &Instr, const BitVector &ForbiddenRegisters) const {
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if (auto E = IsInvalidOpcode(Instr))
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return std::move(E);
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// LEA gets special attention.
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const auto Opcode = Instr.Description->getOpcode();
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if (Opcode == X86::LEA64r || Opcode == X86::LEA64_32r) {
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return generateLEATemplatesCommon(Instr, ForbiddenRegisters, State, Opts,
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[](unsigned BaseReg, unsigned IndexReg) {
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// We just select the same base and
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// output register.
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return BaseReg;
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});
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}
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switch (getX86FPFlags(Instr)) {
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case llvm::X86II::NotFP:
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return LatencySnippetGenerator::generateCodeTemplates(Instr,
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ForbiddenRegisters);
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case llvm::X86II::ZeroArgFP:
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case llvm::X86II::OneArgFP:
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case llvm::X86II::SpecialFP:
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case llvm::X86II::CompareFP:
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case llvm::X86II::CondMovFP:
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return llvm::make_error<Failure>("Unsupported x87 Instruction");
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case llvm::X86II::OneArgFPRW:
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case llvm::X86II::TwoArgFP:
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// These are instructions like
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// - `ST(0) = fsqrt(ST(0))` (OneArgFPRW)
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// - `ST(0) = ST(0) + ST(i)` (TwoArgFP)
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// They are intrinsically serial and do not modify the state of the stack.
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return generateSelfAliasingCodeTemplates(Instr);
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default:
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llvm_unreachable("Unknown FP Type!");
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}
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}
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namespace {
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class X86UopsSnippetGenerator : public UopsSnippetGenerator {
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public:
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using UopsSnippetGenerator::UopsSnippetGenerator;
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llvm::Expected<std::vector<CodeTemplate>>
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generateCodeTemplates(const Instruction &Instr,
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const BitVector &ForbiddenRegisters) const override;
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};
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} // namespace
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llvm::Expected<std::vector<CodeTemplate>>
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X86UopsSnippetGenerator::generateCodeTemplates(
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const Instruction &Instr, const BitVector &ForbiddenRegisters) const {
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if (auto E = IsInvalidOpcode(Instr))
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return std::move(E);
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// LEA gets special attention.
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const auto Opcode = Instr.Description->getOpcode();
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if (Opcode == X86::LEA64r || Opcode == X86::LEA64_32r) {
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// Any destination register that is not used for adddressing is fine.
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auto PossibleDestRegs =
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Instr.Operands[0].getRegisterAliasing().sourceBits();
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remove(PossibleDestRegs, ForbiddenRegisters);
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return generateLEATemplatesCommon(
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Instr, ForbiddenRegisters, State, Opts,
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[this, &PossibleDestRegs](unsigned BaseReg, unsigned IndexReg) {
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auto PossibleDestRegsNow = PossibleDestRegs;
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remove(PossibleDestRegsNow,
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State.getRATC().getRegister(BaseReg).aliasedBits());
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remove(PossibleDestRegsNow,
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State.getRATC().getRegister(IndexReg).aliasedBits());
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assert(PossibleDestRegsNow.set_bits().begin() !=
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PossibleDestRegsNow.set_bits().end() &&
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"no remaining registers");
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return *PossibleDestRegsNow.set_bits().begin();
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});
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}
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switch (getX86FPFlags(Instr)) {
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case llvm::X86II::NotFP:
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return UopsSnippetGenerator::generateCodeTemplates(Instr,
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ForbiddenRegisters);
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case llvm::X86II::ZeroArgFP:
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case llvm::X86II::OneArgFP:
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case llvm::X86II::SpecialFP:
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return llvm::make_error<Failure>("Unsupported x87 Instruction");
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case llvm::X86II::OneArgFPRW:
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case llvm::X86II::TwoArgFP:
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// These are instructions like
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// - `ST(0) = fsqrt(ST(0))` (OneArgFPRW)
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// - `ST(0) = ST(0) + ST(i)` (TwoArgFP)
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// They are intrinsically serial and do not modify the state of the stack.
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// We generate the same code for latency and uops.
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return generateSelfAliasingCodeTemplates(Instr);
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case llvm::X86II::CompareFP:
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case llvm::X86II::CondMovFP:
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// We can compute uops for any FP instruction that does not grow or shrink
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// the stack (either do not touch the stack or push as much as they pop).
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return generateUnconstrainedCodeTemplates(
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Instr, "instruction does not grow/shrink the FP stack");
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default:
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llvm_unreachable("Unknown FP Type!");
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}
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}
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static unsigned getLoadImmediateOpcode(unsigned RegBitWidth) {
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switch (RegBitWidth) {
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case 8:
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return llvm::X86::MOV8ri;
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case 16:
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return llvm::X86::MOV16ri;
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case 32:
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return llvm::X86::MOV32ri;
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case 64:
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return llvm::X86::MOV64ri;
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}
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llvm_unreachable("Invalid Value Width");
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}
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// Generates instruction to load an immediate value into a register.
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static llvm::MCInst loadImmediate(unsigned Reg, unsigned RegBitWidth,
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const llvm::APInt &Value) {
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if (Value.getBitWidth() > RegBitWidth)
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llvm_unreachable("Value must fit in the Register");
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return llvm::MCInstBuilder(getLoadImmediateOpcode(RegBitWidth))
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.addReg(Reg)
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.addImm(Value.getZExtValue());
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}
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// Allocates scratch memory on the stack.
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static llvm::MCInst allocateStackSpace(unsigned Bytes) {
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return llvm::MCInstBuilder(llvm::X86::SUB64ri8)
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.addReg(llvm::X86::RSP)
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.addReg(llvm::X86::RSP)
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.addImm(Bytes);
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}
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// Fills scratch memory at offset `OffsetBytes` with value `Imm`.
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static llvm::MCInst fillStackSpace(unsigned MovOpcode, unsigned OffsetBytes,
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uint64_t Imm) {
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return llvm::MCInstBuilder(MovOpcode)
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// Address = ESP
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.addReg(llvm::X86::RSP) // BaseReg
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.addImm(1) // ScaleAmt
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.addReg(0) // IndexReg
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.addImm(OffsetBytes) // Disp
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.addReg(0) // Segment
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// Immediate.
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.addImm(Imm);
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}
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// Loads scratch memory into register `Reg` using opcode `RMOpcode`.
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static llvm::MCInst loadToReg(unsigned Reg, unsigned RMOpcode) {
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return llvm::MCInstBuilder(RMOpcode)
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.addReg(Reg)
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// Address = ESP
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.addReg(llvm::X86::RSP) // BaseReg
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.addImm(1) // ScaleAmt
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.addReg(0) // IndexReg
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.addImm(0) // Disp
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.addReg(0); // Segment
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}
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// Releases scratch memory.
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static llvm::MCInst releaseStackSpace(unsigned Bytes) {
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return llvm::MCInstBuilder(llvm::X86::ADD64ri8)
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.addReg(llvm::X86::RSP)
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.addReg(llvm::X86::RSP)
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.addImm(Bytes);
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}
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// Reserves some space on the stack, fills it with the content of the provided
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// constant and provide methods to load the stack value into a register.
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namespace {
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struct ConstantInliner {
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explicit ConstantInliner(const llvm::APInt &Constant) : Constant_(Constant) {}
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std::vector<llvm::MCInst> loadAndFinalize(unsigned Reg, unsigned RegBitWidth,
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unsigned Opcode);
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std::vector<llvm::MCInst> loadX87STAndFinalize(unsigned Reg);
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std::vector<llvm::MCInst> loadX87FPAndFinalize(unsigned Reg);
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std::vector<llvm::MCInst> popFlagAndFinalize();
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private:
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ConstantInliner &add(const llvm::MCInst &Inst) {
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Instructions.push_back(Inst);
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return *this;
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}
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void initStack(unsigned Bytes);
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static constexpr const unsigned kF80Bytes = 10; // 80 bits.
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llvm::APInt Constant_;
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std::vector<llvm::MCInst> Instructions;
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};
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} // namespace
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std::vector<llvm::MCInst> ConstantInliner::loadAndFinalize(unsigned Reg,
|
|
unsigned RegBitWidth,
|
|
unsigned Opcode) {
|
|
assert((RegBitWidth & 7) == 0 && "RegBitWidth must be a multiple of 8 bits");
|
|
initStack(RegBitWidth / 8);
|
|
add(loadToReg(Reg, Opcode));
|
|
add(releaseStackSpace(RegBitWidth / 8));
|
|
return std::move(Instructions);
|
|
}
|
|
|
|
std::vector<llvm::MCInst> ConstantInliner::loadX87STAndFinalize(unsigned Reg) {
|
|
initStack(kF80Bytes);
|
|
add(llvm::MCInstBuilder(llvm::X86::LD_F80m)
|
|
// Address = ESP
|
|
.addReg(llvm::X86::RSP) // BaseReg
|
|
.addImm(1) // ScaleAmt
|
|
.addReg(0) // IndexReg
|
|
.addImm(0) // Disp
|
|
.addReg(0)); // Segment
|
|
if (Reg != llvm::X86::ST0)
|
|
add(llvm::MCInstBuilder(llvm::X86::ST_Frr).addReg(Reg));
|
|
add(releaseStackSpace(kF80Bytes));
|
|
return std::move(Instructions);
|
|
}
|
|
|
|
std::vector<llvm::MCInst> ConstantInliner::loadX87FPAndFinalize(unsigned Reg) {
|
|
initStack(kF80Bytes);
|
|
add(llvm::MCInstBuilder(llvm::X86::LD_Fp80m)
|
|
.addReg(Reg)
|
|
// Address = ESP
|
|
.addReg(llvm::X86::RSP) // BaseReg
|
|
.addImm(1) // ScaleAmt
|
|
.addReg(0) // IndexReg
|
|
.addImm(0) // Disp
|
|
.addReg(0)); // Segment
|
|
add(releaseStackSpace(kF80Bytes));
|
|
return std::move(Instructions);
|
|
}
|
|
|
|
std::vector<llvm::MCInst> ConstantInliner::popFlagAndFinalize() {
|
|
initStack(8);
|
|
add(llvm::MCInstBuilder(llvm::X86::POPF64));
|
|
return std::move(Instructions);
|
|
}
|
|
|
|
void ConstantInliner::initStack(unsigned Bytes) {
|
|
assert(Constant_.getBitWidth() <= Bytes * 8 &&
|
|
"Value does not have the correct size");
|
|
const llvm::APInt WideConstant = Constant_.getBitWidth() < Bytes * 8
|
|
? Constant_.sext(Bytes * 8)
|
|
: Constant_;
|
|
add(allocateStackSpace(Bytes));
|
|
size_t ByteOffset = 0;
|
|
for (; Bytes - ByteOffset >= 4; ByteOffset += 4)
|
|
add(fillStackSpace(
|
|
llvm::X86::MOV32mi, ByteOffset,
|
|
WideConstant.extractBits(32, ByteOffset * 8).getZExtValue()));
|
|
if (Bytes - ByteOffset >= 2) {
|
|
add(fillStackSpace(
|
|
llvm::X86::MOV16mi, ByteOffset,
|
|
WideConstant.extractBits(16, ByteOffset * 8).getZExtValue()));
|
|
ByteOffset += 2;
|
|
}
|
|
if (Bytes - ByteOffset >= 1)
|
|
add(fillStackSpace(
|
|
llvm::X86::MOV8mi, ByteOffset,
|
|
WideConstant.extractBits(8, ByteOffset * 8).getZExtValue()));
|
|
}
|
|
|
|
#include "X86GenExegesis.inc"
|
|
|
|
namespace {
|
|
class ExegesisX86Target : public ExegesisTarget {
|
|
public:
|
|
ExegesisX86Target() : ExegesisTarget(X86CpuPfmCounters) {}
|
|
|
|
private:
|
|
void addTargetSpecificPasses(llvm::PassManagerBase &PM) const override;
|
|
|
|
unsigned getScratchMemoryRegister(const llvm::Triple &TT) const override;
|
|
|
|
unsigned getLoopCounterRegister(const llvm::Triple &) const override;
|
|
|
|
unsigned getMaxMemoryAccessSize() const override { return 64; }
|
|
|
|
void randomizeMCOperand(const Instruction &Instr, const Variable &Var,
|
|
llvm::MCOperand &AssignedValue,
|
|
const llvm::BitVector &ForbiddenRegs) const override;
|
|
|
|
void fillMemoryOperands(InstructionTemplate &IT, unsigned Reg,
|
|
unsigned Offset) const override;
|
|
|
|
void decrementLoopCounterAndJump(MachineBasicBlock &MBB,
|
|
MachineBasicBlock &TargetMBB,
|
|
const llvm::MCInstrInfo &MII) const override;
|
|
|
|
std::vector<llvm::MCInst> setRegTo(const llvm::MCSubtargetInfo &STI,
|
|
unsigned Reg,
|
|
const llvm::APInt &Value) const override;
|
|
|
|
ArrayRef<unsigned> getUnavailableRegisters() const override {
|
|
return makeArrayRef(kUnavailableRegisters,
|
|
sizeof(kUnavailableRegisters) /
|
|
sizeof(kUnavailableRegisters[0]));
|
|
}
|
|
|
|
std::unique_ptr<SnippetGenerator> createLatencySnippetGenerator(
|
|
const LLVMState &State,
|
|
const SnippetGenerator::Options &Opts) const override {
|
|
return std::make_unique<X86LatencySnippetGenerator>(State, Opts);
|
|
}
|
|
|
|
std::unique_ptr<SnippetGenerator> createUopsSnippetGenerator(
|
|
const LLVMState &State,
|
|
const SnippetGenerator::Options &Opts) const override {
|
|
return std::make_unique<X86UopsSnippetGenerator>(State, Opts);
|
|
}
|
|
|
|
bool matchesArch(llvm::Triple::ArchType Arch) const override {
|
|
return Arch == llvm::Triple::x86_64 || Arch == llvm::Triple::x86;
|
|
}
|
|
|
|
static const unsigned kUnavailableRegisters[4];
|
|
};
|
|
|
|
// We disable a few registers that cannot be encoded on instructions with a REX
|
|
// prefix.
|
|
const unsigned ExegesisX86Target::kUnavailableRegisters[4] = {X86::AH, X86::BH,
|
|
X86::CH, X86::DH};
|
|
|
|
// We're using one of R8-R15 because these registers are never hardcoded in
|
|
// instructions (e.g. MOVS writes to EDI, ESI, EDX), so they have less
|
|
// conflicts.
|
|
constexpr const unsigned kLoopCounterReg = X86::R8;
|
|
|
|
} // namespace
|
|
|
|
void ExegesisX86Target::addTargetSpecificPasses(
|
|
llvm::PassManagerBase &PM) const {
|
|
// Lowers FP pseudo-instructions, e.g. ABS_Fp32 -> ABS_F.
|
|
PM.add(llvm::createX86FloatingPointStackifierPass());
|
|
}
|
|
|
|
unsigned
|
|
ExegesisX86Target::getScratchMemoryRegister(const llvm::Triple &TT) const {
|
|
if (!TT.isArch64Bit()) {
|
|
// FIXME: This would require popping from the stack, so we would have to
|
|
// add some additional setup code.
|
|
return 0;
|
|
}
|
|
return TT.isOSWindows() ? llvm::X86::RCX : llvm::X86::RDI;
|
|
}
|
|
|
|
unsigned
|
|
ExegesisX86Target::getLoopCounterRegister(const llvm::Triple &TT) const {
|
|
if (!TT.isArch64Bit()) {
|
|
return 0;
|
|
}
|
|
return kLoopCounterReg;
|
|
}
|
|
|
|
void ExegesisX86Target::randomizeMCOperand(
|
|
const Instruction &Instr, const Variable &Var,
|
|
llvm::MCOperand &AssignedValue,
|
|
const llvm::BitVector &ForbiddenRegs) const {
|
|
ExegesisTarget::randomizeMCOperand(Instr, Var, AssignedValue, ForbiddenRegs);
|
|
|
|
const Operand &Op = Instr.getPrimaryOperand(Var);
|
|
switch (Op.getExplicitOperandInfo().OperandType) {
|
|
case llvm::X86::OperandType::OPERAND_COND_CODE:
|
|
AssignedValue = llvm::MCOperand::createImm(
|
|
randomIndex(llvm::X86::CondCode::LAST_VALID_COND));
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
void ExegesisX86Target::fillMemoryOperands(InstructionTemplate &IT,
|
|
unsigned Reg,
|
|
unsigned Offset) const {
|
|
assert(!isInvalidMemoryInstr(IT.Instr) &&
|
|
"fillMemoryOperands requires a valid memory instruction");
|
|
int MemOpIdx = X86II::getMemoryOperandNo(IT.Instr.Description->TSFlags);
|
|
assert(MemOpIdx >= 0 && "invalid memory operand index");
|
|
// getMemoryOperandNo() ignores tied operands, so we have to add them back.
|
|
for (unsigned I = 0; I <= static_cast<unsigned>(MemOpIdx); ++I) {
|
|
const auto &Op = IT.Instr.Operands[I];
|
|
if (Op.isTied() && Op.getTiedToIndex() < I) {
|
|
++MemOpIdx;
|
|
}
|
|
}
|
|
setMemOp(IT, MemOpIdx + 0, MCOperand::createReg(Reg)); // BaseReg
|
|
setMemOp(IT, MemOpIdx + 1, MCOperand::createImm(1)); // ScaleAmt
|
|
setMemOp(IT, MemOpIdx + 2, MCOperand::createReg(0)); // IndexReg
|
|
setMemOp(IT, MemOpIdx + 3, MCOperand::createImm(Offset)); // Disp
|
|
setMemOp(IT, MemOpIdx + 4, MCOperand::createReg(0)); // Segment
|
|
}
|
|
|
|
void ExegesisX86Target::decrementLoopCounterAndJump(
|
|
MachineBasicBlock &MBB, MachineBasicBlock &TargetMBB,
|
|
const llvm::MCInstrInfo &MII) const {
|
|
BuildMI(&MBB, DebugLoc(), MII.get(X86::ADD64ri8))
|
|
.addDef(kLoopCounterReg)
|
|
.addUse(kLoopCounterReg)
|
|
.addImm(-1);
|
|
BuildMI(&MBB, DebugLoc(), MII.get(X86::JCC_1))
|
|
.addMBB(&TargetMBB)
|
|
.addImm(X86::COND_NE);
|
|
}
|
|
|
|
std::vector<llvm::MCInst>
|
|
ExegesisX86Target::setRegTo(const llvm::MCSubtargetInfo &STI, unsigned Reg,
|
|
const llvm::APInt &Value) const {
|
|
if (llvm::X86::GR8RegClass.contains(Reg))
|
|
return {loadImmediate(Reg, 8, Value)};
|
|
if (llvm::X86::GR16RegClass.contains(Reg))
|
|
return {loadImmediate(Reg, 16, Value)};
|
|
if (llvm::X86::GR32RegClass.contains(Reg))
|
|
return {loadImmediate(Reg, 32, Value)};
|
|
if (llvm::X86::GR64RegClass.contains(Reg))
|
|
return {loadImmediate(Reg, 64, Value)};
|
|
ConstantInliner CI(Value);
|
|
if (llvm::X86::VR64RegClass.contains(Reg))
|
|
return CI.loadAndFinalize(Reg, 64, llvm::X86::MMX_MOVQ64rm);
|
|
if (llvm::X86::VR128XRegClass.contains(Reg)) {
|
|
if (STI.getFeatureBits()[llvm::X86::FeatureAVX512])
|
|
return CI.loadAndFinalize(Reg, 128, llvm::X86::VMOVDQU32Z128rm);
|
|
if (STI.getFeatureBits()[llvm::X86::FeatureAVX])
|
|
return CI.loadAndFinalize(Reg, 128, llvm::X86::VMOVDQUrm);
|
|
return CI.loadAndFinalize(Reg, 128, llvm::X86::MOVDQUrm);
|
|
}
|
|
if (llvm::X86::VR256XRegClass.contains(Reg)) {
|
|
if (STI.getFeatureBits()[llvm::X86::FeatureAVX512])
|
|
return CI.loadAndFinalize(Reg, 256, llvm::X86::VMOVDQU32Z256rm);
|
|
if (STI.getFeatureBits()[llvm::X86::FeatureAVX])
|
|
return CI.loadAndFinalize(Reg, 256, llvm::X86::VMOVDQUYrm);
|
|
}
|
|
if (llvm::X86::VR512RegClass.contains(Reg))
|
|
if (STI.getFeatureBits()[llvm::X86::FeatureAVX512])
|
|
return CI.loadAndFinalize(Reg, 512, llvm::X86::VMOVDQU32Zrm);
|
|
if (llvm::X86::RSTRegClass.contains(Reg)) {
|
|
return CI.loadX87STAndFinalize(Reg);
|
|
}
|
|
if (llvm::X86::RFP32RegClass.contains(Reg) ||
|
|
llvm::X86::RFP64RegClass.contains(Reg) ||
|
|
llvm::X86::RFP80RegClass.contains(Reg)) {
|
|
return CI.loadX87FPAndFinalize(Reg);
|
|
}
|
|
if (Reg == llvm::X86::EFLAGS)
|
|
return CI.popFlagAndFinalize();
|
|
return {}; // Not yet implemented.
|
|
}
|
|
|
|
static ExegesisTarget *getTheExegesisX86Target() {
|
|
static ExegesisX86Target Target;
|
|
return &Target;
|
|
}
|
|
|
|
void InitializeX86ExegesisTarget() {
|
|
ExegesisTarget::registerTarget(getTheExegesisX86Target());
|
|
}
|
|
|
|
} // namespace exegesis
|
|
} // namespace llvm
|