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 "TargetInfo/X86TargetInfo.h"
  16 #include "MCTargetDesc/X86BaseInfo.h"
  17 #include "llvm/MC/TargetRegistry.h"
  18 #include "llvm/Support/WithColor.h"
  19
  20 namespace llvm {
  21 namespace mca {
  22
  23 void X86InstrPostProcess::setMemBarriers(std::unique_ptr<Instruction> &Inst,
  24                                          const MCInst &MCI) {
  25   switch (MCI.getOpcode()) {
  26   case X86::MFENCE:
  27     Inst->setLoadBarrier(true);
  28     Inst->setStoreBarrier(true);
  29     break;
  30   case X86::LFENCE:
  31     Inst->setLoadBarrier(true);
  32     break;
  33   case X86::SFENCE:
  34     Inst->setStoreBarrier(true);
  35     break;
  36   }
  37 }
  38
  39 void X86InstrPostProcess::postProcessInstruction(
  40     std::unique_ptr<Instruction> &Inst, const MCInst &MCI) {
  41   // Currently, we only modify certain instructions' IsALoadBarrier and
  42   // IsAStoreBarrier flags.
  43   setMemBarriers(Inst, MCI);
  44 }
  45
  46 } // namespace mca
  47 } // namespace llvm
  48
  49 using namespace llvm;
  50 using namespace mca;
  51
  52 static InstrPostProcess *createX86InstrPostProcess(const MCSubtargetInfo &STI,
  53                                                    const MCInstrInfo &MCII) {
  54   return new X86InstrPostProcess(STI, MCII);
  55 }
  56
  57 /// Extern function to initialize the targets for the X86 backend
  58
  59 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeX86TargetMCA() {
  60   TargetRegistry::RegisterInstrPostProcess(getTheX86_32Target(),
  61                                            createX86InstrPostProcess);
  62   TargetRegistry::RegisterInstrPostProcess(getTheX86_64Target(),
  63                                            createX86InstrPostProcess);
  64 }