llvm/lib/Target/X86/MCA/X86CustomBehaviour.cpp

   1 //===------------------- X86CustomBehaviour.cpp -----------------*-C++ -* -===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 /// \file
   9 ///
  10 /// This file implements methods from the X86CustomBehaviour class.
  11 ///
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "X86CustomBehaviour.h"
  15 #include "MCTargetDesc/X86BaseInfo.h"
  16 #include "TargetInfo/X86TargetInfo.h"
  17 #include "llvm/MC/TargetRegistry.h"
  18
  19 namespace llvm {
  20 namespace mca {
  21
  22 void X86InstrPostProcess::setMemBarriers(std::unique_ptr<Instruction> &Inst,
  23                                          const MCInst &MCI) {
  24   switch (MCI.getOpcode()) {
  25   case X86::MFENCE:
  26     Inst->setLoadBarrier(true);
  27     Inst->setStoreBarrier(true);
  28     break;
  29   case X86::LFENCE:
  30     Inst->setLoadBarrier(true);
  31     break;
  32   case X86::SFENCE:
  33     Inst->setStoreBarrier(true);
  34     break;
  35   }
  36 }
  37
  38 void X86InstrPostProcess::postProcessInstruction(
  39     std::unique_ptr<Instruction> &Inst, const MCInst &MCI) {
  40   // Currently, we only modify certain instructions' IsALoadBarrier and
  41   // IsAStoreBarrier flags.
  42   setMemBarriers(Inst, MCI);
  43 }
  44
  45 } // namespace mca
  46 } // namespace llvm
  47
  48 using namespace llvm;
  49 using namespace mca;
  50
  51 static InstrPostProcess *createX86InstrPostProcess(const MCSubtargetInfo &STI,
  52                                                    const MCInstrInfo &MCII) {
  53   return new X86InstrPostProcess(STI, MCII);
  54 }
  55
  56 /// Extern function to initialize the targets for the X86 backend
  57
  58 extern "C" LLVM_C_ABI void LLVMInitializeX86TargetMCA() {
  59   TargetRegistry::RegisterInstrPostProcess(getTheX86_32Target(),
  60                                            createX86InstrPostProcess);
  61   TargetRegistry::RegisterInstrPostProcess(getTheX86_64Target(),
  62                                            createX86InstrPostProcess);
  63 }