llvm/lib/Target/Mips/MipsTargetMachine.cpp - rust-lang/llvm-project - Git at Google

 //===-- MipsTargetMachine.cpp - Define TargetMachine for Mips -------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // Implements the info about Mips target spec.
 //
 //===----------------------------------------------------------------------===//

 #include "MipsTargetMachine.h"
 #include "MCTargetDesc/MipsABIInfo.h"
 #include "MCTargetDesc/MipsMCTargetDesc.h"
 #include "Mips.h"
 #include "Mips16ISelDAGToDAG.h"
 #include "MipsSEISelDAGToDAG.h"
 #include "MipsSubtarget.h"
 #include "MipsTargetObjectFile.h"
 #include "MipsTargetTransformInfo.h"
 #include "TargetInfo/MipsTargetInfo.h"
 #include "llvm/ADT/Optional.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
 #include "llvm/CodeGen/BasicTTIImpl.h"
 #include "llvm/CodeGen/GlobalISel/CSEInfo.h"
 #include "llvm/CodeGen/GlobalISel/IRTranslator.h"
 #include "llvm/CodeGen/GlobalISel/InstructionSelect.h"
 #include "llvm/CodeGen/GlobalISel/Legalizer.h"
 #include "llvm/CodeGen/GlobalISel/RegBankSelect.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/Passes.h"
 #include "llvm/CodeGen/TargetPassConfig.h"
 #include "llvm/IR/Attributes.h"
 #include "llvm/IR/Function.h"
 #include "llvm/InitializePasses.h"
 #include "llvm/MC/TargetRegistry.h"
 #include "llvm/Support/CodeGen.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Target/TargetOptions.h"
 #include <string>

 using namespace llvm;

 #define DEBUG_TYPE "mips"

 static cl::opt<bool>
     EnableMulMulFix("mfix4300", cl::init(false),
                     cl::desc("Enable the VR4300 mulmul bug fix."), cl::Hidden);

 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMipsTarget() {
   // Register the target.
   RegisterTargetMachine<MipsebTargetMachine> X(getTheMipsTarget());
   RegisterTargetMachine<MipselTargetMachine> Y(getTheMipselTarget());
   RegisterTargetMachine<MipsebTargetMachine> A(getTheMips64Target());
   RegisterTargetMachine<MipselTargetMachine> B(getTheMips64elTarget());

   PassRegistry *PR = PassRegistry::getPassRegistry();
   initializeGlobalISel(*PR);
   initializeMipsDelaySlotFillerPass(*PR);
   initializeMipsBranchExpansionPass(*PR);
   initializeMicroMipsSizeReducePass(*PR);
   initializeMipsPreLegalizerCombinerPass(*PR);
   initializeMipsPostLegalizerCombinerPass(*PR);
   initializeMipsMulMulBugFixPass(*PR);
 }

 static std::string computeDataLayout(const Triple &TT, StringRef CPU,
                                      const TargetOptions &Options,
                                      bool isLittle) {
   std::string Ret;
   MipsABIInfo ABI = MipsABIInfo::computeTargetABI(TT, CPU, Options.MCOptions);

   // There are both little and big endian mips.
   if (isLittle)
     Ret += "e";
   else
     Ret += "E";

   if (ABI.IsO32())
     Ret += "-m:m";
   else
     Ret += "-m:e";

   // Pointers are 32 bit on some ABIs.
   if (!ABI.IsN64())
     Ret += "-p:32:32";

   // 8 and 16 bit integers only need to have natural alignment, but try to
   // align them to 32 bits. 64 bit integers have natural alignment.
   Ret += "-i8:8:32-i16:16:32-i64:64";

   // 32 bit registers are always available and the stack is at least 64 bit
   // aligned. On N64 64 bit registers are also available and the stack is
   // 128 bit aligned.
   if (ABI.IsN64() || ABI.IsN32())
     Ret += "-n32:64-S128";
   else
     Ret += "-n32-S64";

   return Ret;
 }

 static Reloc::Model getEffectiveRelocModel(bool JIT,
                                            Optional<Reloc::Model> RM) {
   if (!RM || JIT)
     return Reloc::Static;
   return *RM;
 }

 // On function prologue, the stack is created by decrementing
 // its pointer. Once decremented, all references are done with positive
 // offset from the stack/frame pointer, using StackGrowsUp enables
 // an easier handling.
 // Using CodeModel::Large enables different CALL behavior.
 MipsTargetMachine::MipsTargetMachine(const Target &T, const Triple &TT,
                                      StringRef CPU, StringRef FS,
                                      const TargetOptions &Options,
                                      Optional<Reloc::Model> RM,
                                      Optional<CodeModel::Model> CM,
                                      CodeGenOpt::Level OL, bool JIT,
                                      bool isLittle)
     : LLVMTargetMachine(T, computeDataLayout(TT, CPU, Options, isLittle), TT,
                         CPU, FS, Options, getEffectiveRelocModel(JIT, RM),
                         getEffectiveCodeModel(CM, CodeModel::Small), OL),
       isLittle(isLittle), TLOF(std::make_unique<MipsTargetObjectFile>()),
       ABI(MipsABIInfo::computeTargetABI(TT, CPU, Options.MCOptions)),
       Subtarget(nullptr), DefaultSubtarget(TT, CPU, FS, isLittle, *this, None),
       NoMips16Subtarget(TT, CPU, FS.empty() ? "-mips16" : FS.str() + ",-mips16",
                         isLittle, *this, None),
       Mips16Subtarget(TT, CPU, FS.empty() ? "+mips16" : FS.str() + ",+mips16",
                       isLittle, *this, None) {
   Subtarget = &DefaultSubtarget;
   initAsmInfo();

   // Mips supports the debug entry values.
   setSupportsDebugEntryValues(true);
 }

 MipsTargetMachine::~MipsTargetMachine() = default;

 void MipsebTargetMachine::anchor() {}

 MipsebTargetMachine::MipsebTargetMachine(const Target &T, const Triple &TT,
                                          StringRef CPU, StringRef FS,
                                          const TargetOptions &Options,
                                          Optional<Reloc::Model> RM,
                                          Optional<CodeModel::Model> CM,
                                          CodeGenOpt::Level OL, bool JIT)
     : MipsTargetMachine(T, TT, CPU, FS, Options, RM, CM, OL, JIT, false) {}

 void MipselTargetMachine::anchor() {}

 MipselTargetMachine::MipselTargetMachine(const Target &T, const Triple &TT,
                                          StringRef CPU, StringRef FS,
                                          const TargetOptions &Options,
                                          Optional<Reloc::Model> RM,
                                          Optional<CodeModel::Model> CM,
                                          CodeGenOpt::Level OL, bool JIT)
     : MipsTargetMachine(T, TT, CPU, FS, Options, RM, CM, OL, JIT, true) {}

 const MipsSubtarget *
 MipsTargetMachine::getSubtargetImpl(const Function &F) const {
   Attribute CPUAttr = F.getFnAttribute("target-cpu");
   Attribute FSAttr = F.getFnAttribute("target-features");

   std::string CPU =
       CPUAttr.isValid() ? CPUAttr.getValueAsString().str() : TargetCPU;
   std::string FS =
       FSAttr.isValid() ? FSAttr.getValueAsString().str() : TargetFS;
   bool hasMips16Attr = F.getFnAttribute("mips16").isValid();
   bool hasNoMips16Attr = F.getFnAttribute("nomips16").isValid();

   bool HasMicroMipsAttr = F.getFnAttribute("micromips").isValid();
   bool HasNoMicroMipsAttr = F.getFnAttribute("nomicromips").isValid();

   // FIXME: This is related to the code below to reset the target options,
   // we need to know whether or not the soft float flag is set on the
   // function, so we can enable it as a subtarget feature.
   bool softFloat = F.getFnAttribute("use-soft-float").getValueAsBool();

   if (hasMips16Attr)
     FS += FS.empty() ? "+mips16" : ",+mips16";
   else if (hasNoMips16Attr)
     FS += FS.empty() ? "-mips16" : ",-mips16";
   if (HasMicroMipsAttr)
     FS += FS.empty() ? "+micromips" : ",+micromips";
   else if (HasNoMicroMipsAttr)
     FS += FS.empty() ? "-micromips" : ",-micromips";
   if (softFloat)
     FS += FS.empty() ? "+soft-float" : ",+soft-float";

   auto &I = SubtargetMap[CPU + FS];
   if (!I) {
     // This needs to be done before we create a new subtarget since any
     // creation will depend on the TM and the code generation flags on the
     // function that reside in TargetOptions.
     resetTargetOptions(F);
     I = std::make_unique<MipsSubtarget>(
         TargetTriple, CPU, FS, isLittle, *this,
         MaybeAlign(F.getParent()->getOverrideStackAlignment()));
   }
   return I.get();
 }

 void MipsTargetMachine::resetSubtarget(MachineFunction *MF) {
   LLVM_DEBUG(dbgs() << "resetSubtarget\n");

   Subtarget = &MF->getSubtarget<MipsSubtarget>();
 }

 namespace {

 /// Mips Code Generator Pass Configuration Options.
 class MipsPassConfig : public TargetPassConfig {
 public:
   MipsPassConfig(MipsTargetMachine &TM, PassManagerBase &PM)
       : TargetPassConfig(TM, PM) {
     // The current implementation of long branch pass requires a scratch
     // register ($at) to be available before branch instructions. Tail merging
     // can break this requirement, so disable it when long branch pass is
     // enabled.
     EnableTailMerge = !getMipsSubtarget().enableLongBranchPass();
   }

   MipsTargetMachine &getMipsTargetMachine() const {
     return getTM<MipsTargetMachine>();
   }

   const MipsSubtarget &getMipsSubtarget() const {
     return *getMipsTargetMachine().getSubtargetImpl();
   }

   void addIRPasses() override;
   bool addInstSelector() override;
   void addPreEmitPass() override;
   void addPreRegAlloc() override;
   bool addIRTranslator() override;
   void addPreLegalizeMachineIR() override;
   bool addLegalizeMachineIR() override;
   void addPreRegBankSelect() override;
   bool addRegBankSelect() override;
   bool addGlobalInstructionSelect() override;

   std::unique_ptr<CSEConfigBase> getCSEConfig() const override;
 };

 } // end anonymous namespace

 TargetPassConfig *MipsTargetMachine::createPassConfig(PassManagerBase &PM) {
   return new MipsPassConfig(*this, PM);
 }

 std::unique_ptr<CSEConfigBase> MipsPassConfig::getCSEConfig() const {
   return getStandardCSEConfigForOpt(TM->getOptLevel());
 }

 void MipsPassConfig::addIRPasses() {
   TargetPassConfig::addIRPasses();
   addPass(createAtomicExpandPass());
   if (getMipsSubtarget().os16())
     addPass(createMipsOs16Pass());
   if (getMipsSubtarget().inMips16HardFloat())
     addPass(createMips16HardFloatPass());
 }
 // Install an instruction selector pass using
 // the ISelDag to gen Mips code.
 bool MipsPassConfig::addInstSelector() {
   addPass(createMipsModuleISelDagPass());
   addPass(createMips16ISelDag(getMipsTargetMachine(), getOptLevel()));
   addPass(createMipsSEISelDag(getMipsTargetMachine(), getOptLevel()));
   return false;
 }

 void MipsPassConfig::addPreRegAlloc() {
   addPass(createMipsOptimizePICCallPass());
 }

 TargetTransformInfo
 MipsTargetMachine::getTargetTransformInfo(const Function &F) const {
   if (Subtarget->allowMixed16_32()) {
     LLVM_DEBUG(errs() << "No Target Transform Info Pass Added\n");
     // FIXME: This is no longer necessary as the TTI returned is per-function.
     return TargetTransformInfo(F.getParent()->getDataLayout());
   }

   LLVM_DEBUG(errs() << "Target Transform Info Pass Added\n");
   return TargetTransformInfo(MipsTTIImpl(this, F));
 }

 // Implemented by targets that want to run passes immediately before
 // machine code is emitted.
 void MipsPassConfig::addPreEmitPass() {
   // Expand pseudo instructions that are sensitive to register allocation.
   addPass(createMipsExpandPseudoPass());

   // The microMIPS size reduction pass performs instruction reselection for
   // instructions which can be remapped to a 16 bit instruction.
   addPass(createMicroMipsSizeReducePass());

   // This pass inserts a nop instruction between two back-to-back multiplication
   // instructions when the "mfix4300" flag is passed.
   if (EnableMulMulFix)
     addPass(createMipsMulMulBugPass());

   // The delay slot filler pass can potientially create forbidden slot hazards
   // for MIPSR6 and therefore it should go before MipsBranchExpansion pass.
   addPass(createMipsDelaySlotFillerPass());

   // This pass expands branches and takes care about the forbidden slot hazards.
   // Expanding branches may potentially create forbidden slot hazards for
   // MIPSR6, and fixing such hazard may potentially break a branch by extending
   // its offset out of range. That's why this pass combine these two tasks, and
   // runs them alternately until one of them finishes without any changes. Only
   // then we can be sure that all branches are expanded properly and no hazards
   // exists.
   // Any new pass should go before this pass.
   addPass(createMipsBranchExpansion());

   addPass(createMipsConstantIslandPass());
 }

 bool MipsPassConfig::addIRTranslator() {
   addPass(new IRTranslator(getOptLevel()));
   return false;
 }

 void MipsPassConfig::addPreLegalizeMachineIR() {
   addPass(createMipsPreLegalizeCombiner());
 }

 bool MipsPassConfig::addLegalizeMachineIR() {
   addPass(new Legalizer());
   return false;
 }

 void MipsPassConfig::addPreRegBankSelect() {
   bool IsOptNone = getOptLevel() == CodeGenOpt::None;
   addPass(createMipsPostLegalizeCombiner(IsOptNone));
 }

 bool MipsPassConfig::addRegBankSelect() {
   addPass(new RegBankSelect());
   return false;
 }

 bool MipsPassConfig::addGlobalInstructionSelect() {
   addPass(new InstructionSelect(getOptLevel()));
   return false;
 }
	//===-- MipsTargetMachine.cpp - Define TargetMachine for Mips -------------===//
	//
	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
	// See https://llvm.org/LICENSE.txt for license information.
	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
	//
	//===----------------------------------------------------------------------===//
	//
	// Implements the info about Mips target spec.
	//
	//===----------------------------------------------------------------------===//

	#include "MipsTargetMachine.h"
	#include "MCTargetDesc/MipsABIInfo.h"
	#include "MCTargetDesc/MipsMCTargetDesc.h"
	#include "Mips.h"
	#include "Mips16ISelDAGToDAG.h"
	#include "MipsSEISelDAGToDAG.h"
	#include "MipsSubtarget.h"
	#include "MipsTargetObjectFile.h"
	#include "MipsTargetTransformInfo.h"
	#include "TargetInfo/MipsTargetInfo.h"
	#include "llvm/ADT/Optional.h"
	#include "llvm/ADT/STLExtras.h"
	#include "llvm/ADT/StringRef.h"
	#include "llvm/Analysis/TargetTransformInfo.h"
	#include "llvm/CodeGen/BasicTTIImpl.h"
	#include "llvm/CodeGen/GlobalISel/CSEInfo.h"
	#include "llvm/CodeGen/GlobalISel/IRTranslator.h"
	#include "llvm/CodeGen/GlobalISel/InstructionSelect.h"
	#include "llvm/CodeGen/GlobalISel/Legalizer.h"
	#include "llvm/CodeGen/GlobalISel/RegBankSelect.h"
	#include "llvm/CodeGen/MachineFunction.h"
	#include "llvm/CodeGen/Passes.h"
	#include "llvm/CodeGen/TargetPassConfig.h"
	#include "llvm/IR/Attributes.h"
	#include "llvm/IR/Function.h"
	#include "llvm/InitializePasses.h"
	#include "llvm/MC/TargetRegistry.h"
	#include "llvm/Support/CodeGen.h"
	#include "llvm/Support/Debug.h"
	#include "llvm/Support/raw_ostream.h"
	#include "llvm/Target/TargetOptions.h"
	#include <string>

	using namespace llvm;

	#define DEBUG_TYPE "mips"

	static cl::opt<bool>
	EnableMulMulFix("mfix4300", cl::init(false),
	cl::desc("Enable the VR4300 mulmul bug fix."), cl::Hidden);

	extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMipsTarget() {
	// Register the target.
	RegisterTargetMachine<MipsebTargetMachine> X(getTheMipsTarget());
	RegisterTargetMachine<MipselTargetMachine> Y(getTheMipselTarget());
	RegisterTargetMachine<MipsebTargetMachine> A(getTheMips64Target());
	RegisterTargetMachine<MipselTargetMachine> B(getTheMips64elTarget());

	PassRegistry *PR = PassRegistry::getPassRegistry();
	initializeGlobalISel(*PR);
	initializeMipsDelaySlotFillerPass(*PR);
	initializeMipsBranchExpansionPass(*PR);
	initializeMicroMipsSizeReducePass(*PR);
	initializeMipsPreLegalizerCombinerPass(*PR);
	initializeMipsPostLegalizerCombinerPass(*PR);
	initializeMipsMulMulBugFixPass(*PR);
	}

	static std::string computeDataLayout(const Triple &TT, StringRef CPU,
	const TargetOptions &Options,
	bool isLittle) {
	std::string Ret;
	MipsABIInfo ABI = MipsABIInfo::computeTargetABI(TT, CPU, Options.MCOptions);

	// There are both little and big endian mips.
	if (isLittle)
	Ret += "e";
	else
	Ret += "E";

	if (ABI.IsO32())
	Ret += "-m:m";
	else
	Ret += "-m:e";

	// Pointers are 32 bit on some ABIs.
	if (!ABI.IsN64())
	Ret += "-p:32:32";

	// 8 and 16 bit integers only need to have natural alignment, but try to
	// align them to 32 bits. 64 bit integers have natural alignment.
	Ret += "-i8:8:32-i16:16:32-i64:64";

	// 32 bit registers are always available and the stack is at least 64 bit
	// aligned. On N64 64 bit registers are also available and the stack is
	// 128 bit aligned.
	if (ABI.IsN64() \|\| ABI.IsN32())
	Ret += "-n32:64-S128";
	else
	Ret += "-n32-S64";

	return Ret;
	}

	static Reloc::Model getEffectiveRelocModel(bool JIT,
	Optional<Reloc::Model> RM) {
	if (!RM \|\| JIT)
	return Reloc::Static;
	return *RM;
	}

	// On function prologue, the stack is created by decrementing
	// its pointer. Once decremented, all references are done with positive
	// offset from the stack/frame pointer, using StackGrowsUp enables
	// an easier handling.
	// Using CodeModel::Large enables different CALL behavior.
	MipsTargetMachine::MipsTargetMachine(const Target &T, const Triple &TT,
	StringRef CPU, StringRef FS,
	const TargetOptions &Options,
	Optional<Reloc::Model> RM,
	Optional<CodeModel::Model> CM,
	CodeGenOpt::Level OL, bool JIT,
	bool isLittle)
	: LLVMTargetMachine(T, computeDataLayout(TT, CPU, Options, isLittle), TT,
	CPU, FS, Options, getEffectiveRelocModel(JIT, RM),
	getEffectiveCodeModel(CM, CodeModel::Small), OL),
	isLittle(isLittle), TLOF(std::make_unique<MipsTargetObjectFile>()),
	ABI(MipsABIInfo::computeTargetABI(TT, CPU, Options.MCOptions)),
	Subtarget(nullptr), DefaultSubtarget(TT, CPU, FS, isLittle, *this, None),
	NoMips16Subtarget(TT, CPU, FS.empty() ? "-mips16" : FS.str() + ",-mips16",
	isLittle, *this, None),
	Mips16Subtarget(TT, CPU, FS.empty() ? "+mips16" : FS.str() + ",+mips16",
	isLittle, *this, None) {
	Subtarget = &DefaultSubtarget;
	initAsmInfo();

	// Mips supports the debug entry values.
	setSupportsDebugEntryValues(true);
	}

	MipsTargetMachine::~MipsTargetMachine() = default;

	void MipsebTargetMachine::anchor() {}

	MipsebTargetMachine::MipsebTargetMachine(const Target &T, const Triple &TT,
	StringRef CPU, StringRef FS,
	const TargetOptions &Options,
	Optional<Reloc::Model> RM,
	Optional<CodeModel::Model> CM,
	CodeGenOpt::Level OL, bool JIT)
	: MipsTargetMachine(T, TT, CPU, FS, Options, RM, CM, OL, JIT, false) {}

	void MipselTargetMachine::anchor() {}

	MipselTargetMachine::MipselTargetMachine(const Target &T, const Triple &TT,
	StringRef CPU, StringRef FS,
	const TargetOptions &Options,
	Optional<Reloc::Model> RM,
	Optional<CodeModel::Model> CM,
	CodeGenOpt::Level OL, bool JIT)
	: MipsTargetMachine(T, TT, CPU, FS, Options, RM, CM, OL, JIT, true) {}

	const MipsSubtarget *
	MipsTargetMachine::getSubtargetImpl(const Function &F) const {
	Attribute CPUAttr = F.getFnAttribute("target-cpu");
	Attribute FSAttr = F.getFnAttribute("target-features");

	std::string CPU =
	CPUAttr.isValid() ? CPUAttr.getValueAsString().str() : TargetCPU;
	std::string FS =
	FSAttr.isValid() ? FSAttr.getValueAsString().str() : TargetFS;
	bool hasMips16Attr = F.getFnAttribute("mips16").isValid();
	bool hasNoMips16Attr = F.getFnAttribute("nomips16").isValid();

	bool HasMicroMipsAttr = F.getFnAttribute("micromips").isValid();
	bool HasNoMicroMipsAttr = F.getFnAttribute("nomicromips").isValid();

	// FIXME: This is related to the code below to reset the target options,
	// we need to know whether or not the soft float flag is set on the
	// function, so we can enable it as a subtarget feature.
	bool softFloat = F.getFnAttribute("use-soft-float").getValueAsBool();

	if (hasMips16Attr)
	FS += FS.empty() ? "+mips16" : ",+mips16";
	else if (hasNoMips16Attr)
	FS += FS.empty() ? "-mips16" : ",-mips16";
	if (HasMicroMipsAttr)
	FS += FS.empty() ? "+micromips" : ",+micromips";
	else if (HasNoMicroMipsAttr)
	FS += FS.empty() ? "-micromips" : ",-micromips";
	if (softFloat)
	FS += FS.empty() ? "+soft-float" : ",+soft-float";

	auto &I = SubtargetMap[CPU + FS];
	if (!I) {
	// This needs to be done before we create a new subtarget since any
	// creation will depend on the TM and the code generation flags on the
	// function that reside in TargetOptions.
	resetTargetOptions(F);
	I = std::make_unique<MipsSubtarget>(
	TargetTriple, CPU, FS, isLittle, *this,
	MaybeAlign(F.getParent()->getOverrideStackAlignment()));
	}
	return I.get();
	}

	void MipsTargetMachine::resetSubtarget(MachineFunction *MF) {
	LLVM_DEBUG(dbgs() << "resetSubtarget\n");

	Subtarget = &MF->getSubtarget<MipsSubtarget>();
	}

	namespace {

	/// Mips Code Generator Pass Configuration Options.
	class MipsPassConfig : public TargetPassConfig {
	public:
	MipsPassConfig(MipsTargetMachine &TM, PassManagerBase &PM)
	: TargetPassConfig(TM, PM) {
	// The current implementation of long branch pass requires a scratch
	// register ($at) to be available before branch instructions. Tail merging
	// can break this requirement, so disable it when long branch pass is
	// enabled.
	EnableTailMerge = !getMipsSubtarget().enableLongBranchPass();
	}

	MipsTargetMachine &getMipsTargetMachine() const {
	return getTM<MipsTargetMachine>();
	}

	const MipsSubtarget &getMipsSubtarget() const {
	return *getMipsTargetMachine().getSubtargetImpl();
	}

	void addIRPasses() override;
	bool addInstSelector() override;
	void addPreEmitPass() override;
	void addPreRegAlloc() override;
	bool addIRTranslator() override;
	void addPreLegalizeMachineIR() override;
	bool addLegalizeMachineIR() override;
	void addPreRegBankSelect() override;
	bool addRegBankSelect() override;
	bool addGlobalInstructionSelect() override;

	std::unique_ptr<CSEConfigBase> getCSEConfig() const override;
	};

	} // end anonymous namespace

	TargetPassConfig *MipsTargetMachine::createPassConfig(PassManagerBase &PM) {
	return new MipsPassConfig(*this, PM);
	}

	std::unique_ptr<CSEConfigBase> MipsPassConfig::getCSEConfig() const {
	return getStandardCSEConfigForOpt(TM->getOptLevel());
	}

	void MipsPassConfig::addIRPasses() {
	TargetPassConfig::addIRPasses();
	addPass(createAtomicExpandPass());
	if (getMipsSubtarget().os16())
	addPass(createMipsOs16Pass());
	if (getMipsSubtarget().inMips16HardFloat())
	addPass(createMips16HardFloatPass());
	}
	// Install an instruction selector pass using
	// the ISelDag to gen Mips code.
	bool MipsPassConfig::addInstSelector() {
	addPass(createMipsModuleISelDagPass());
	addPass(createMips16ISelDag(getMipsTargetMachine(), getOptLevel()));
	addPass(createMipsSEISelDag(getMipsTargetMachine(), getOptLevel()));
	return false;
	}

	void MipsPassConfig::addPreRegAlloc() {
	addPass(createMipsOptimizePICCallPass());
	}

	TargetTransformInfo
	MipsTargetMachine::getTargetTransformInfo(const Function &F) const {
	if (Subtarget->allowMixed16_32()) {
	LLVM_DEBUG(errs() << "No Target Transform Info Pass Added\n");
	// FIXME: This is no longer necessary as the TTI returned is per-function.
	return TargetTransformInfo(F.getParent()->getDataLayout());
	}

	LLVM_DEBUG(errs() << "Target Transform Info Pass Added\n");
	return TargetTransformInfo(MipsTTIImpl(this, F));
	}

	// Implemented by targets that want to run passes immediately before
	// machine code is emitted.
	void MipsPassConfig::addPreEmitPass() {
	// Expand pseudo instructions that are sensitive to register allocation.
	addPass(createMipsExpandPseudoPass());

	// The microMIPS size reduction pass performs instruction reselection for
	// instructions which can be remapped to a 16 bit instruction.
	addPass(createMicroMipsSizeReducePass());

	// This pass inserts a nop instruction between two back-to-back multiplication
	// instructions when the "mfix4300" flag is passed.
	if (EnableMulMulFix)
	addPass(createMipsMulMulBugPass());

	// The delay slot filler pass can potientially create forbidden slot hazards
	// for MIPSR6 and therefore it should go before MipsBranchExpansion pass.
	addPass(createMipsDelaySlotFillerPass());

	// This pass expands branches and takes care about the forbidden slot hazards.
	// Expanding branches may potentially create forbidden slot hazards for
	// MIPSR6, and fixing such hazard may potentially break a branch by extending
	// its offset out of range. That's why this pass combine these two tasks, and
	// runs them alternately until one of them finishes without any changes. Only
	// then we can be sure that all branches are expanded properly and no hazards
	// exists.
	// Any new pass should go before this pass.
	addPass(createMipsBranchExpansion());

	addPass(createMipsConstantIslandPass());
	}

	bool MipsPassConfig::addIRTranslator() {
	addPass(new IRTranslator(getOptLevel()));
	return false;
	}

	void MipsPassConfig::addPreLegalizeMachineIR() {
	addPass(createMipsPreLegalizeCombiner());
	}

	bool MipsPassConfig::addLegalizeMachineIR() {
	addPass(new Legalizer());
	return false;
	}

	void MipsPassConfig::addPreRegBankSelect() {
	bool IsOptNone = getOptLevel() == CodeGenOpt::None;
	addPass(createMipsPostLegalizeCombiner(IsOptNone));
	}

	bool MipsPassConfig::addRegBankSelect() {
	addPass(new RegBankSelect());
	return false;
	}

	bool MipsPassConfig::addGlobalInstructionSelect() {
	addPass(new InstructionSelect(getOptLevel()));
	return false;
	}