llvm-project/llvm/lib/CodeGen/LLVMTargetMachine.cpp

327 lines
12 KiB
C++

//===-- LLVMTargetMachine.cpp - Implement the LLVMTargetMachine class -----===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the LLVMTargetMachine class.
//
//===----------------------------------------------------------------------===//
#include "llvm/Target/TargetMachine.h"
#include "llvm/Analysis/Passes.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/BasicTTIImpl.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/CodeGen/TargetPassConfig.h"
#include "llvm/IR/IRPrintingPasses.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/IR/Verifier.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCInstrInfo.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Target/TargetLoweringObjectFile.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Transforms/Scalar.h"
using namespace llvm;
// Enable or disable FastISel. Both options are needed, because
// FastISel is enabled by default with -fast, and we wish to be
// able to enable or disable fast-isel independently from -O0.
static cl::opt<cl::boolOrDefault>
EnableFastISelOption("fast-isel", cl::Hidden,
cl::desc("Enable the \"fast\" instruction selector"));
static cl::opt<cl::boolOrDefault>
EnableGlobalISel("global-isel", cl::Hidden,
cl::desc("Enable the \"global\" instruction selector"));
void LLVMTargetMachine::initAsmInfo() {
MRI = TheTarget.createMCRegInfo(getTargetTriple().str());
MII = TheTarget.createMCInstrInfo();
// FIXME: Having an MCSubtargetInfo on the target machine is a hack due
// to some backends having subtarget feature dependent module level
// code generation. This is similar to the hack in the AsmPrinter for
// module level assembly etc.
STI = TheTarget.createMCSubtargetInfo(getTargetTriple().str(), getTargetCPU(),
getTargetFeatureString());
MCAsmInfo *TmpAsmInfo =
TheTarget.createMCAsmInfo(*MRI, getTargetTriple().str());
// TargetSelect.h moved to a different directory between LLVM 2.9 and 3.0,
// and if the old one gets included then MCAsmInfo will be NULL and
// we'll crash later.
// Provide the user with a useful error message about what's wrong.
assert(TmpAsmInfo && "MCAsmInfo not initialized. "
"Make sure you include the correct TargetSelect.h"
"and that InitializeAllTargetMCs() is being invoked!");
if (Options.DisableIntegratedAS)
TmpAsmInfo->setUseIntegratedAssembler(false);
TmpAsmInfo->setPreserveAsmComments(Options.MCOptions.PreserveAsmComments);
if (Options.CompressDebugSections)
TmpAsmInfo->setCompressDebugSections(DebugCompressionType::DCT_ZlibGnu);
TmpAsmInfo->setRelaxELFRelocations(Options.RelaxELFRelocations);
if (Options.ExceptionModel != ExceptionHandling::None)
TmpAsmInfo->setExceptionsType(Options.ExceptionModel);
AsmInfo = TmpAsmInfo;
}
LLVMTargetMachine::LLVMTargetMachine(const Target &T,
StringRef DataLayoutString,
const Triple &TT, StringRef CPU,
StringRef FS, const TargetOptions &Options,
Reloc::Model RM, CodeModel::Model CM,
CodeGenOpt::Level OL)
: TargetMachine(T, DataLayoutString, TT, CPU, FS, Options) {
T.adjustCodeGenOpts(TT, RM, CM);
this->RM = RM;
this->CMModel = CM;
this->OptLevel = OL;
}
TargetIRAnalysis LLVMTargetMachine::getTargetIRAnalysis() {
return TargetIRAnalysis([this](const Function &F) {
return TargetTransformInfo(BasicTTIImpl(this, F));
});
}
/// addPassesToX helper drives creation and initialization of TargetPassConfig.
static MCContext *
addPassesToGenerateCode(LLVMTargetMachine *TM, PassManagerBase &PM,
bool DisableVerify, AnalysisID StartBefore,
AnalysisID StartAfter, AnalysisID StopBefore,
AnalysisID StopAfter,
MachineFunctionInitializer *MFInitializer = nullptr) {
// Targets may override createPassConfig to provide a target-specific
// subclass.
TargetPassConfig *PassConfig = TM->createPassConfig(PM);
PassConfig->setStartStopPasses(StartBefore, StartAfter, StopBefore,
StopAfter);
// Set PassConfig options provided by TargetMachine.
PassConfig->setDisableVerify(DisableVerify);
PM.add(PassConfig);
// When in emulated TLS mode, add the LowerEmuTLS pass.
if (TM->Options.EmulatedTLS)
PM.add(createLowerEmuTLSPass());
PM.add(createPreISelIntrinsicLoweringPass());
// Add internal analysis passes from the target machine.
PM.add(createTargetTransformInfoWrapperPass(TM->getTargetIRAnalysis()));
PassConfig->addIRPasses();
PassConfig->addCodeGenPrepare();
PassConfig->addPassesToHandleExceptions();
PassConfig->addISelPrepare();
MachineModuleInfo *MMI = new MachineModuleInfo(TM);
MMI->setMachineFunctionInitializer(MFInitializer);
PM.add(MMI);
// Enable FastISel with -fast, but allow that to be overridden.
TM->setO0WantsFastISel(EnableFastISelOption != cl::BOU_FALSE);
if (EnableFastISelOption == cl::BOU_TRUE ||
(TM->getOptLevel() == CodeGenOpt::None &&
TM->getO0WantsFastISel()))
TM->setFastISel(true);
// Ask the target for an isel.
// Enable GlobalISel if the target wants to, but allow that to be overriden.
if (EnableGlobalISel == cl::BOU_TRUE || (EnableGlobalISel == cl::BOU_UNSET &&
PassConfig->isGlobalISelEnabled())) {
if (PassConfig->addIRTranslator())
return nullptr;
PassConfig->addPreLegalizeMachineIR();
if (PassConfig->addLegalizeMachineIR())
return nullptr;
// Before running the register bank selector, ask the target if it
// wants to run some passes.
PassConfig->addPreRegBankSelect();
if (PassConfig->addRegBankSelect())
return nullptr;
PassConfig->addPreGlobalInstructionSelect();
if (PassConfig->addGlobalInstructionSelect())
return nullptr;
// Pass to reset the MachineFunction if the ISel failed.
PM.add(createResetMachineFunctionPass(
PassConfig->reportDiagnosticWhenGlobalISelFallback(),
PassConfig->isGlobalISelAbortEnabled()));
// Provide a fallback path when we do not want to abort on
// not-yet-supported input.
if (!PassConfig->isGlobalISelAbortEnabled() &&
PassConfig->addInstSelector())
return nullptr;
} else if (PassConfig->addInstSelector())
return nullptr;
PassConfig->addMachinePasses();
PassConfig->setInitialized();
return &MMI->getContext();
}
bool LLVMTargetMachine::addPassesToEmitFile(
PassManagerBase &PM, raw_pwrite_stream &Out, CodeGenFileType FileType,
bool DisableVerify, AnalysisID StartBefore, AnalysisID StartAfter,
AnalysisID StopBefore, AnalysisID StopAfter,
MachineFunctionInitializer *MFInitializer) {
// Add common CodeGen passes.
MCContext *Context =
addPassesToGenerateCode(this, PM, DisableVerify, StartBefore, StartAfter,
StopBefore, StopAfter, MFInitializer);
if (!Context)
return true;
if (StopBefore || StopAfter) {
PM.add(createPrintMIRPass(Out));
return false;
}
if (Options.MCOptions.MCSaveTempLabels)
Context->setAllowTemporaryLabels(false);
const MCSubtargetInfo &STI = *getMCSubtargetInfo();
const MCAsmInfo &MAI = *getMCAsmInfo();
const MCRegisterInfo &MRI = *getMCRegisterInfo();
const MCInstrInfo &MII = *getMCInstrInfo();
std::unique_ptr<MCStreamer> AsmStreamer;
switch (FileType) {
case CGFT_AssemblyFile: {
MCInstPrinter *InstPrinter = getTarget().createMCInstPrinter(
getTargetTriple(), MAI.getAssemblerDialect(), MAI, MII, MRI);
// Create a code emitter if asked to show the encoding.
MCCodeEmitter *MCE = nullptr;
if (Options.MCOptions.ShowMCEncoding)
MCE = getTarget().createMCCodeEmitter(MII, MRI, *Context);
MCAsmBackend *MAB =
getTarget().createMCAsmBackend(MRI, getTargetTriple().str(), TargetCPU,
Options.MCOptions);
auto FOut = llvm::make_unique<formatted_raw_ostream>(Out);
MCStreamer *S = getTarget().createAsmStreamer(
*Context, std::move(FOut), Options.MCOptions.AsmVerbose,
Options.MCOptions.MCUseDwarfDirectory, InstPrinter, MCE, MAB,
Options.MCOptions.ShowMCInst);
AsmStreamer.reset(S);
break;
}
case CGFT_ObjectFile: {
// Create the code emitter for the target if it exists. If not, .o file
// emission fails.
MCCodeEmitter *MCE = getTarget().createMCCodeEmitter(MII, MRI, *Context);
MCAsmBackend *MAB =
getTarget().createMCAsmBackend(MRI, getTargetTriple().str(), TargetCPU,
Options.MCOptions);
if (!MCE || !MAB)
return true;
// Don't waste memory on names of temp labels.
Context->setUseNamesOnTempLabels(false);
Triple T(getTargetTriple().str());
AsmStreamer.reset(getTarget().createMCObjectStreamer(
T, *Context, *MAB, Out, MCE, STI, Options.MCOptions.MCRelaxAll,
Options.MCOptions.MCIncrementalLinkerCompatible,
/*DWARFMustBeAtTheEnd*/ true));
break;
}
case CGFT_Null:
// The Null output is intended for use for performance analysis and testing,
// not real users.
AsmStreamer.reset(getTarget().createNullStreamer(*Context));
break;
}
// Create the AsmPrinter, which takes ownership of AsmStreamer if successful.
FunctionPass *Printer =
getTarget().createAsmPrinter(*this, std::move(AsmStreamer));
if (!Printer)
return true;
PM.add(Printer);
PM.add(createFreeMachineFunctionPass());
return false;
}
/// addPassesToEmitMC - Add passes to the specified pass manager to get
/// machine code emitted with the MCJIT. This method returns true if machine
/// code is not supported. It fills the MCContext Ctx pointer which can be
/// used to build custom MCStreamer.
///
bool LLVMTargetMachine::addPassesToEmitMC(PassManagerBase &PM, MCContext *&Ctx,
raw_pwrite_stream &Out,
bool DisableVerify) {
// Add common CodeGen passes.
Ctx = addPassesToGenerateCode(this, PM, DisableVerify, nullptr, nullptr,
nullptr, nullptr);
if (!Ctx)
return true;
if (Options.MCOptions.MCSaveTempLabels)
Ctx->setAllowTemporaryLabels(false);
// Create the code emitter for the target if it exists. If not, .o file
// emission fails.
const MCRegisterInfo &MRI = *getMCRegisterInfo();
MCCodeEmitter *MCE =
getTarget().createMCCodeEmitter(*getMCInstrInfo(), MRI, *Ctx);
MCAsmBackend *MAB =
getTarget().createMCAsmBackend(MRI, getTargetTriple().str(), TargetCPU,
Options.MCOptions);
if (!MCE || !MAB)
return true;
const Triple &T = getTargetTriple();
const MCSubtargetInfo &STI = *getMCSubtargetInfo();
std::unique_ptr<MCStreamer> AsmStreamer(getTarget().createMCObjectStreamer(
T, *Ctx, *MAB, Out, MCE, STI, Options.MCOptions.MCRelaxAll,
Options.MCOptions.MCIncrementalLinkerCompatible,
/*DWARFMustBeAtTheEnd*/ true));
// Create the AsmPrinter, which takes ownership of AsmStreamer if successful.
FunctionPass *Printer =
getTarget().createAsmPrinter(*this, std::move(AsmStreamer));
if (!Printer)
return true;
PM.add(Printer);
PM.add(createFreeMachineFunctionPass());
return false; // success!
}