llvm-project/llvm/tools/llc/llc.cpp

644 lines
21 KiB
C++

//===-- llc.cpp - Implement the LLVM Native Code Generator ----------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// This is the llc code generator driver. It provides a convenient
// command-line interface for generating native assembly-language code
// or C code, given LLVM bitcode.
//
//===----------------------------------------------------------------------===//
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/CodeGen/CommandFlags.inc"
#include "llvm/CodeGen/LinkAllAsmWriterComponents.h"
#include "llvm/CodeGen/LinkAllCodegenComponents.h"
#include "llvm/CodeGen/MIRParser/MIRParser.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/TargetPassConfig.h"
#include "llvm/CodeGen/TargetSubtargetInfo.h"
#include "llvm/IR/AutoUpgrade.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DiagnosticInfo.h"
#include "llvm/IR/DiagnosticPrinter.h"
#include "llvm/IR/IRPrintingPasses.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/RemarkStreamer.h"
#include "llvm/IR/Verifier.h"
#include "llvm/IRReader/IRReader.h"
#include "llvm/MC/SubtargetFeature.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Support/Host.h"
#include "llvm/Support/InitLLVM.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/PluginLoader.h"
#include "llvm/Support/SourceMgr.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/TargetSelect.h"
#include "llvm/Support/ToolOutputFile.h"
#include "llvm/Support/WithColor.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Transforms/Utils/Cloning.h"
#include <memory>
using namespace llvm;
// General options for llc. Other pass-specific options are specified
// within the corresponding llc passes, and target-specific options
// and back-end code generation options are specified with the target machine.
//
static cl::opt<std::string>
InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
static cl::opt<std::string>
InputLanguage("x", cl::desc("Input language ('ir' or 'mir')"));
static cl::opt<std::string>
OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
static cl::opt<std::string>
SplitDwarfOutputFile("split-dwarf-output",
cl::desc(".dwo output filename"),
cl::value_desc("filename"));
static cl::opt<unsigned>
TimeCompilations("time-compilations", cl::Hidden, cl::init(1u),
cl::value_desc("N"),
cl::desc("Repeat compilation N times for timing"));
static cl::opt<bool>
NoIntegratedAssembler("no-integrated-as", cl::Hidden,
cl::desc("Disable integrated assembler"));
static cl::opt<bool>
PreserveComments("preserve-as-comments", cl::Hidden,
cl::desc("Preserve Comments in outputted assembly"),
cl::init(true));
// Determine optimization level.
static cl::opt<char>
OptLevel("O",
cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
"(default = '-O2')"),
cl::Prefix,
cl::ZeroOrMore,
cl::init(' '));
static cl::opt<std::string>
TargetTriple("mtriple", cl::desc("Override target triple for module"));
static cl::opt<std::string> SplitDwarfFile(
"split-dwarf-file",
cl::desc(
"Specify the name of the .dwo file to encode in the DWARF output"));
static cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
cl::desc("Do not verify input module"));
static cl::opt<bool> DisableSimplifyLibCalls("disable-simplify-libcalls",
cl::desc("Disable simplify-libcalls"));
static cl::opt<bool> ShowMCEncoding("show-mc-encoding", cl::Hidden,
cl::desc("Show encoding in .s output"));
static cl::opt<bool> EnableDwarfDirectory(
"enable-dwarf-directory", cl::Hidden,
cl::desc("Use .file directives with an explicit directory."));
static cl::opt<bool> AsmVerbose("asm-verbose",
cl::desc("Add comments to directives."),
cl::init(true));
static cl::opt<bool>
CompileTwice("compile-twice", cl::Hidden,
cl::desc("Run everything twice, re-using the same pass "
"manager and verify the result is the same."),
cl::init(false));
static cl::opt<bool> DiscardValueNames(
"discard-value-names",
cl::desc("Discard names from Value (other than GlobalValue)."),
cl::init(false), cl::Hidden);
static cl::list<std::string> IncludeDirs("I", cl::desc("include search path"));
static cl::opt<bool> PassRemarksWithHotness(
"pass-remarks-with-hotness",
cl::desc("With PGO, include profile count in optimization remarks"),
cl::Hidden);
static cl::opt<unsigned> PassRemarksHotnessThreshold(
"pass-remarks-hotness-threshold",
cl::desc("Minimum profile count required for an optimization remark to be output"),
cl::Hidden);
static cl::opt<std::string>
RemarksFilename("pass-remarks-output",
cl::desc("YAML output filename for pass remarks"),
cl::value_desc("filename"));
static cl::opt<std::string>
RemarksPasses("pass-remarks-filter",
cl::desc("Only record optimization remarks from passes whose "
"names match the given regular expression"),
cl::value_desc("regex"));
namespace {
static ManagedStatic<std::vector<std::string>> RunPassNames;
struct RunPassOption {
void operator=(const std::string &Val) const {
if (Val.empty())
return;
SmallVector<StringRef, 8> PassNames;
StringRef(Val).split(PassNames, ',', -1, false);
for (auto PassName : PassNames)
RunPassNames->push_back(PassName);
}
};
}
static RunPassOption RunPassOpt;
static cl::opt<RunPassOption, true, cl::parser<std::string>> RunPass(
"run-pass",
cl::desc("Run compiler only for specified passes (comma separated list)"),
cl::value_desc("pass-name"), cl::ZeroOrMore, cl::location(RunPassOpt));
static int compileModule(char **, LLVMContext &);
static std::unique_ptr<ToolOutputFile> GetOutputStream(const char *TargetName,
Triple::OSType OS,
const char *ProgName) {
// If we don't yet have an output filename, make one.
if (OutputFilename.empty()) {
if (InputFilename == "-")
OutputFilename = "-";
else {
// If InputFilename ends in .bc or .ll, remove it.
StringRef IFN = InputFilename;
if (IFN.endswith(".bc") || IFN.endswith(".ll"))
OutputFilename = IFN.drop_back(3);
else if (IFN.endswith(".mir"))
OutputFilename = IFN.drop_back(4);
else
OutputFilename = IFN;
switch (FileType) {
case TargetMachine::CGFT_AssemblyFile:
if (TargetName[0] == 'c') {
if (TargetName[1] == 0)
OutputFilename += ".cbe.c";
else if (TargetName[1] == 'p' && TargetName[2] == 'p')
OutputFilename += ".cpp";
else
OutputFilename += ".s";
} else
OutputFilename += ".s";
break;
case TargetMachine::CGFT_ObjectFile:
if (OS == Triple::Win32)
OutputFilename += ".obj";
else
OutputFilename += ".o";
break;
case TargetMachine::CGFT_Null:
OutputFilename += ".null";
break;
}
}
}
// Decide if we need "binary" output.
bool Binary = false;
switch (FileType) {
case TargetMachine::CGFT_AssemblyFile:
break;
case TargetMachine::CGFT_ObjectFile:
case TargetMachine::CGFT_Null:
Binary = true;
break;
}
// Open the file.
std::error_code EC;
sys::fs::OpenFlags OpenFlags = sys::fs::F_None;
if (!Binary)
OpenFlags |= sys::fs::F_Text;
auto FDOut = llvm::make_unique<ToolOutputFile>(OutputFilename, EC, OpenFlags);
if (EC) {
WithColor::error() << EC.message() << '\n';
return nullptr;
}
return FDOut;
}
struct LLCDiagnosticHandler : public DiagnosticHandler {
bool *HasError;
LLCDiagnosticHandler(bool *HasErrorPtr) : HasError(HasErrorPtr) {}
bool handleDiagnostics(const DiagnosticInfo &DI) override {
if (DI.getSeverity() == DS_Error)
*HasError = true;
if (auto *Remark = dyn_cast<DiagnosticInfoOptimizationBase>(&DI))
if (!Remark->isEnabled())
return true;
DiagnosticPrinterRawOStream DP(errs());
errs() << LLVMContext::getDiagnosticMessagePrefix(DI.getSeverity()) << ": ";
DI.print(DP);
errs() << "\n";
return true;
}
};
static void InlineAsmDiagHandler(const SMDiagnostic &SMD, void *Context,
unsigned LocCookie) {
bool *HasError = static_cast<bool *>(Context);
if (SMD.getKind() == SourceMgr::DK_Error)
*HasError = true;
SMD.print(nullptr, errs());
// For testing purposes, we print the LocCookie here.
if (LocCookie)
WithColor::note() << "!srcloc = " << LocCookie << "\n";
}
// main - Entry point for the llc compiler.
//
int main(int argc, char **argv) {
InitLLVM X(argc, argv);
// Enable debug stream buffering.
EnableDebugBuffering = true;
LLVMContext Context;
// Initialize targets first, so that --version shows registered targets.
InitializeAllTargets();
InitializeAllTargetMCs();
InitializeAllAsmPrinters();
InitializeAllAsmParsers();
// Initialize codegen and IR passes used by llc so that the -print-after,
// -print-before, and -stop-after options work.
PassRegistry *Registry = PassRegistry::getPassRegistry();
initializeCore(*Registry);
initializeCodeGen(*Registry);
initializeLoopStrengthReducePass(*Registry);
initializeLowerIntrinsicsPass(*Registry);
initializeEntryExitInstrumenterPass(*Registry);
initializePostInlineEntryExitInstrumenterPass(*Registry);
initializeUnreachableBlockElimLegacyPassPass(*Registry);
initializeConstantHoistingLegacyPassPass(*Registry);
initializeScalarOpts(*Registry);
initializeVectorization(*Registry);
initializeScalarizeMaskedMemIntrinPass(*Registry);
initializeExpandReductionsPass(*Registry);
// Initialize debugging passes.
initializeScavengerTestPass(*Registry);
// Register the target printer for --version.
cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
Context.setDiscardValueNames(DiscardValueNames);
// Set a diagnostic handler that doesn't exit on the first error
bool HasError = false;
Context.setDiagnosticHandler(
llvm::make_unique<LLCDiagnosticHandler>(&HasError));
Context.setInlineAsmDiagnosticHandler(InlineAsmDiagHandler, &HasError);
if (PassRemarksWithHotness)
Context.setDiagnosticsHotnessRequested(true);
if (PassRemarksHotnessThreshold)
Context.setDiagnosticsHotnessThreshold(PassRemarksHotnessThreshold);
std::unique_ptr<ToolOutputFile> YamlFile;
if (RemarksFilename != "") {
std::error_code EC;
YamlFile =
llvm::make_unique<ToolOutputFile>(RemarksFilename, EC, sys::fs::F_None);
if (EC) {
WithColor::error(errs(), argv[0]) << EC.message() << '\n';
return 1;
}
Context.setRemarkStreamer(
llvm::make_unique<RemarkStreamer>(RemarksFilename, YamlFile->os()));
if (!RemarksPasses.empty())
if (Error E = Context.getRemarkStreamer()->setFilter(RemarksPasses)) {
WithColor::error(errs(), argv[0]) << E << '\n';
return 1;
}
}
if (InputLanguage != "" && InputLanguage != "ir" &&
InputLanguage != "mir") {
WithColor::error(errs(), argv[0])
<< "input language must be '', 'IR' or 'MIR'\n";
return 1;
}
// Compile the module TimeCompilations times to give better compile time
// metrics.
for (unsigned I = TimeCompilations; I; --I)
if (int RetVal = compileModule(argv, Context))
return RetVal;
if (YamlFile)
YamlFile->keep();
return 0;
}
static bool addPass(PassManagerBase &PM, const char *argv0,
StringRef PassName, TargetPassConfig &TPC) {
if (PassName == "none")
return false;
const PassRegistry *PR = PassRegistry::getPassRegistry();
const PassInfo *PI = PR->getPassInfo(PassName);
if (!PI) {
WithColor::error(errs(), argv0)
<< "run-pass " << PassName << " is not registered.\n";
return true;
}
Pass *P;
if (PI->getNormalCtor())
P = PI->getNormalCtor()();
else {
WithColor::error(errs(), argv0)
<< "cannot create pass: " << PI->getPassName() << "\n";
return true;
}
std::string Banner = std::string("After ") + std::string(P->getPassName());
PM.add(P);
TPC.printAndVerify(Banner);
return false;
}
static int compileModule(char **argv, LLVMContext &Context) {
// Load the module to be compiled...
SMDiagnostic Err;
std::unique_ptr<Module> M;
std::unique_ptr<MIRParser> MIR;
Triple TheTriple;
bool SkipModule = MCPU == "help" ||
(!MAttrs.empty() && MAttrs.front() == "help");
// If user just wants to list available options, skip module loading
if (!SkipModule) {
if (InputLanguage == "mir" ||
(InputLanguage == "" && StringRef(InputFilename).endswith(".mir"))) {
MIR = createMIRParserFromFile(InputFilename, Err, Context);
if (MIR)
M = MIR->parseIRModule();
} else
M = parseIRFile(InputFilename, Err, Context, false);
if (!M) {
Err.print(argv[0], WithColor::error(errs(), argv[0]));
return 1;
}
// If we are supposed to override the target triple, do so now.
if (!TargetTriple.empty())
M->setTargetTriple(Triple::normalize(TargetTriple));
TheTriple = Triple(M->getTargetTriple());
} else {
TheTriple = Triple(Triple::normalize(TargetTriple));
}
if (TheTriple.getTriple().empty())
TheTriple.setTriple(sys::getDefaultTargetTriple());
// Get the target specific parser.
std::string Error;
const Target *TheTarget = TargetRegistry::lookupTarget(MArch, TheTriple,
Error);
if (!TheTarget) {
WithColor::error(errs(), argv[0]) << Error;
return 1;
}
std::string CPUStr = getCPUStr(), FeaturesStr = getFeaturesStr();
CodeGenOpt::Level OLvl = CodeGenOpt::Default;
switch (OptLevel) {
default:
WithColor::error(errs(), argv[0]) << "invalid optimization level.\n";
return 1;
case ' ': break;
case '0': OLvl = CodeGenOpt::None; break;
case '1': OLvl = CodeGenOpt::Less; break;
case '2': OLvl = CodeGenOpt::Default; break;
case '3': OLvl = CodeGenOpt::Aggressive; break;
}
TargetOptions Options = InitTargetOptionsFromCodeGenFlags();
Options.DisableIntegratedAS = NoIntegratedAssembler;
Options.MCOptions.ShowMCEncoding = ShowMCEncoding;
Options.MCOptions.MCUseDwarfDirectory = EnableDwarfDirectory;
Options.MCOptions.AsmVerbose = AsmVerbose;
Options.MCOptions.PreserveAsmComments = PreserveComments;
Options.MCOptions.IASSearchPaths = IncludeDirs;
Options.MCOptions.SplitDwarfFile = SplitDwarfFile;
std::unique_ptr<TargetMachine> Target(TheTarget->createTargetMachine(
TheTriple.getTriple(), CPUStr, FeaturesStr, Options, getRelocModel(),
getCodeModel(), OLvl));
assert(Target && "Could not allocate target machine!");
// If we don't have a module then just exit now. We do this down
// here since the CPU/Feature help is underneath the target machine
// creation.
if (SkipModule)
return 0;
assert(M && "Should have exited if we didn't have a module!");
if (FloatABIForCalls != FloatABI::Default)
Options.FloatABIType = FloatABIForCalls;
// Figure out where we are going to send the output.
std::unique_ptr<ToolOutputFile> Out =
GetOutputStream(TheTarget->getName(), TheTriple.getOS(), argv[0]);
if (!Out) return 1;
std::unique_ptr<ToolOutputFile> DwoOut;
if (!SplitDwarfOutputFile.empty()) {
std::error_code EC;
DwoOut = llvm::make_unique<ToolOutputFile>(SplitDwarfOutputFile, EC,
sys::fs::F_None);
if (EC) {
WithColor::error(errs(), argv[0]) << EC.message() << '\n';
return 1;
}
}
// Build up all of the passes that we want to do to the module.
legacy::PassManager PM;
// Add an appropriate TargetLibraryInfo pass for the module's triple.
TargetLibraryInfoImpl TLII(Triple(M->getTargetTriple()));
// The -disable-simplify-libcalls flag actually disables all builtin optzns.
if (DisableSimplifyLibCalls)
TLII.disableAllFunctions();
PM.add(new TargetLibraryInfoWrapperPass(TLII));
// Add the target data from the target machine, if it exists, or the module.
M->setDataLayout(Target->createDataLayout());
// This needs to be done after setting datalayout since it calls verifier
// to check debug info whereas verifier relies on correct datalayout.
UpgradeDebugInfo(*M);
// Verify module immediately to catch problems before doInitialization() is
// called on any passes.
if (!NoVerify && verifyModule(*M, &errs())) {
std::string Prefix =
(Twine(argv[0]) + Twine(": ") + Twine(InputFilename)).str();
WithColor::error(errs(), Prefix) << "input module is broken!\n";
return 1;
}
// Override function attributes based on CPUStr, FeaturesStr, and command line
// flags.
setFunctionAttributes(CPUStr, FeaturesStr, *M);
if (RelaxAll.getNumOccurrences() > 0 &&
FileType != TargetMachine::CGFT_ObjectFile)
WithColor::warning(errs(), argv[0])
<< ": warning: ignoring -mc-relax-all because filetype != obj";
{
raw_pwrite_stream *OS = &Out->os();
// Manually do the buffering rather than using buffer_ostream,
// so we can memcmp the contents in CompileTwice mode
SmallVector<char, 0> Buffer;
std::unique_ptr<raw_svector_ostream> BOS;
if ((FileType != TargetMachine::CGFT_AssemblyFile &&
!Out->os().supportsSeeking()) ||
CompileTwice) {
BOS = make_unique<raw_svector_ostream>(Buffer);
OS = BOS.get();
}
const char *argv0 = argv[0];
LLVMTargetMachine &LLVMTM = static_cast<LLVMTargetMachine&>(*Target);
MachineModuleInfo *MMI = new MachineModuleInfo(&LLVMTM);
// Construct a custom pass pipeline that starts after instruction
// selection.
if (!RunPassNames->empty()) {
if (!MIR) {
WithColor::warning(errs(), argv[0])
<< "run-pass is for .mir file only.\n";
return 1;
}
TargetPassConfig &TPC = *LLVMTM.createPassConfig(PM);
if (TPC.hasLimitedCodeGenPipeline()) {
WithColor::warning(errs(), argv[0])
<< "run-pass cannot be used with "
<< TPC.getLimitedCodeGenPipelineReason(" and ") << ".\n";
return 1;
}
TPC.setDisableVerify(NoVerify);
PM.add(&TPC);
PM.add(MMI);
TPC.printAndVerify("");
for (const std::string &RunPassName : *RunPassNames) {
if (addPass(PM, argv0, RunPassName, TPC))
return 1;
}
TPC.setInitialized();
PM.add(createPrintMIRPass(*OS));
PM.add(createFreeMachineFunctionPass());
} else if (Target->addPassesToEmitFile(PM, *OS,
DwoOut ? &DwoOut->os() : nullptr,
FileType, NoVerify, MMI)) {
WithColor::warning(errs(), argv[0])
<< "target does not support generation of this"
<< " file type!\n";
return 1;
}
if (MIR) {
assert(MMI && "Forgot to create MMI?");
if (MIR->parseMachineFunctions(*M, *MMI))
return 1;
}
// Before executing passes, print the final values of the LLVM options.
cl::PrintOptionValues();
// If requested, run the pass manager over the same module again,
// to catch any bugs due to persistent state in the passes. Note that
// opt has the same functionality, so it may be worth abstracting this out
// in the future.
SmallVector<char, 0> CompileTwiceBuffer;
if (CompileTwice) {
std::unique_ptr<Module> M2(llvm::CloneModule(*M));
PM.run(*M2);
CompileTwiceBuffer = Buffer;
Buffer.clear();
}
PM.run(*M);
auto HasError =
((const LLCDiagnosticHandler *)(Context.getDiagHandlerPtr()))->HasError;
if (*HasError)
return 1;
// Compare the two outputs and make sure they're the same
if (CompileTwice) {
if (Buffer.size() != CompileTwiceBuffer.size() ||
(memcmp(Buffer.data(), CompileTwiceBuffer.data(), Buffer.size()) !=
0)) {
errs()
<< "Running the pass manager twice changed the output.\n"
"Writing the result of the second run to the specified output\n"
"To generate the one-run comparison binary, just run without\n"
"the compile-twice option\n";
Out->os() << Buffer;
Out->keep();
return 1;
}
}
if (BOS) {
Out->os() << Buffer;
}
}
// Declare success.
Out->keep();
if (DwoOut)
DwoOut->keep();
return 0;
}