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//===- opt.cpp - The LLVM Modular Optimizer -------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Optimizations may be specified an arbitrary number of times on the command
// line, They are run in the order specified.
//
//===----------------------------------------------------------------------===//
#include "BreakpointPrinter.h"
#include "NewPMDriver.h"
#include "PassPrinters.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Analysis/CallGraph.h"
#include "llvm/Analysis/CallGraphSCCPass.h"
#include "llvm/Analysis/LoopPass.h"
#include "llvm/Analysis/RegionPass.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/Bitcode/BitcodeWriterPass.h"
#include "llvm/CodeGen/CommandFlags.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/IRPrintingPasses.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/IR/LegacyPassNameParser.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Verifier.h"
#include "llvm/IRReader/IRReader.h"
#include "llvm/InitializePasses.h"
#include "llvm/Linker/Linker.h"
#include "llvm/LinkAllIR.h"
#include "llvm/LinkAllPasses.h"
#include "llvm/MC/SubtargetFeature.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/Host.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/PluginLoader.h"
#include "llvm/Support/PrettyStackTrace.h"
#include "llvm/Support/Signals.h"
#include "llvm/Support/SourceMgr.h"
#include "llvm/Support/SystemUtils.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/TargetSelect.h"
#include "llvm/Support/ToolOutputFile.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Transforms/IPO/PassManagerBuilder.h"
#include "llvm/Transforms/Utils/Cloning.h"
#include <algorithm>
#include <memory>
using namespace llvm;
using namespace opt_tool;
// The OptimizationList is automatically populated with registered Passes by the
// PassNameParser.
//
static cl::list<const PassInfo*, bool, PassNameParser>
PassList(cl::desc("Optimizations available:"));
// This flag specifies a textual description of the optimization pass pipeline
// to run over the module. This flag switches opt to use the new pass manager
// infrastructure, completely disabling all of the flags specific to the old
// pass management.
static cl::opt<std::string> PassPipeline(
"passes",
cl::desc("A textual description of the pass pipeline for optimizing"),
cl::Hidden);
// Other command line options...
//
static cl::list<std::string> // XXX EMSCRIPTEN: support multiple input files, link them
InputFilenames(cl::Positional, cl::ZeroOrMore,
cl::desc("<input bitcode files>"));
static cl::opt<std::string>
OutputFilename("o", cl::desc("Override output filename"),
cl::value_desc("filename"));
static cl::opt<bool>
Force("f", cl::desc("Enable binary output on terminals"));
static cl::opt<bool>
PrintEachXForm("p", cl::desc("Print module after each transformation"));
static cl::opt<bool>
NoOutput("disable-output",
cl::desc("Do not write result bitcode file"), cl::Hidden);
static cl::opt<bool>
OutputAssembly("S", cl::desc("Write output as LLVM assembly"));
static cl::opt<bool>
NoVerify("disable-verify", cl::desc("Do not verify result module"), cl::Hidden);
static cl::opt<bool>
VerifyEach("verify-each", cl::desc("Verify after each transform"));
static cl::opt<bool>
StripDebug("strip-debug",
cl::desc("Strip debugger symbol info from translation unit"));
static cl::opt<bool>
DisableInline("disable-inlining", cl::desc("Do not run the inliner pass"));
static cl::opt<bool>
DisableOptimizations("disable-opt",
cl::desc("Do not run any optimization passes"));
static cl::opt<bool>
StandardLinkOpts("std-link-opts",
cl::desc("Include the standard link time optimizations"));
static cl::opt<bool>
OptLevelO1("O1",
cl::desc("Optimization level 1. Similar to clang -O1"));
static cl::opt<bool>
OptLevelO2("O2",
cl::desc("Optimization level 2. Similar to clang -O2"));
static cl::opt<bool>
OptLevelOs("Os",
cl::desc("Like -O2 with extra optimizations for size. Similar to clang -Os"));
static cl::opt<bool>
OptLevelOz("Oz",
cl::desc("Like -Os but reduces code size further. Similar to clang -Oz"));
static cl::opt<bool>
OptLevelO3("O3",
cl::desc("Optimization level 3. Similar to clang -O3"));
static cl::opt<std::string>
TargetTriple("mtriple", cl::desc("Override target triple for module"));
static cl::opt<bool>
UnitAtATime("funit-at-a-time",
cl::desc("Enable IPO. This corresponds to gcc's -funit-at-a-time"),
cl::init(true));
static cl::opt<bool>
DisableLoopUnrolling("disable-loop-unrolling",
cl::desc("Disable loop unrolling in all relevant passes"),
cl::init(false));
static cl::opt<bool>
DisableLoopVectorization("disable-loop-vectorization",
cl::desc("Disable the loop vectorization pass"),
cl::init(false));
static cl::opt<bool>
DisableSLPVectorization("disable-slp-vectorization",
cl::desc("Disable the slp vectorization pass"),
cl::init(false));
static cl::opt<bool>
DisableSimplifyLibCalls("disable-simplify-libcalls",
cl::desc("Disable simplify-libcalls"));
static cl::opt<bool>
Quiet("q", cl::desc("Obsolete option"), cl::Hidden);
static cl::alias
QuietA("quiet", cl::desc("Alias for -q"), cl::aliasopt(Quiet));
static cl::opt<bool>
AnalyzeOnly("analyze", cl::desc("Only perform analysis, no optimization"));
static cl::opt<bool>
PrintBreakpoints("print-breakpoints-for-testing",
cl::desc("Print select breakpoints location for testing"));
static cl::opt<std::string>
DefaultDataLayout("default-data-layout",
cl::desc("data layout string to use if not specified by module"),
cl::value_desc("layout-string"), cl::init(""));
static cl::opt<bool> PreserveBitcodeUseListOrder(
"preserve-bc-uselistorder",
cl::desc("Preserve use-list order when writing LLVM bitcode."),
cl::init(true), cl::Hidden);
static cl::opt<bool> PreserveAssemblyUseListOrder(
"preserve-ll-uselistorder",
cl::desc("Preserve use-list order when writing LLVM assembly."),
cl::init(false), cl::Hidden);
static cl::opt<bool>
RunTwice("run-twice",
cl::desc("Run all passes twice, re-using the same pass manager."),
cl::init(false), cl::Hidden);
static inline void addPass(legacy::PassManagerBase &PM, Pass *P) {
// Add the pass to the pass manager...
PM.add(P);
// If we are verifying all of the intermediate steps, add the verifier...
if (VerifyEach)
PM.add(createVerifierPass());
}
/// This routine adds optimization passes based on selected optimization level,
/// OptLevel.
///
/// OptLevel - Optimization Level
static void AddOptimizationPasses(legacy::PassManagerBase &MPM,
legacy::FunctionPassManager &FPM,
unsigned OptLevel, unsigned SizeLevel) {
FPM.add(createVerifierPass()); // Verify that input is correct
PassManagerBuilder Builder;
Builder.OptLevel = OptLevel;
Builder.SizeLevel = SizeLevel;
if (DisableInline) {
// No inlining pass
} else if (OptLevel > 1) {
Builder.Inliner = createFunctionInliningPass(OptLevel, SizeLevel);
} else {
Builder.Inliner = createAlwaysInlinerPass();
}
Builder.DisableUnitAtATime = !UnitAtATime;
Builder.DisableUnrollLoops = (DisableLoopUnrolling.getNumOccurrences() > 0) ?
DisableLoopUnrolling : OptLevel == 0;
// This is final, unless there is a #pragma vectorize enable
if (DisableLoopVectorization)
Builder.LoopVectorize = false;
// If option wasn't forced via cmd line (-vectorize-loops, -loop-vectorize)
else if (!Builder.LoopVectorize)
Builder.LoopVectorize = OptLevel > 1 && SizeLevel < 2;
// When #pragma vectorize is on for SLP, do the same as above
Builder.SLPVectorize =
DisableSLPVectorization ? false : OptLevel > 1 && SizeLevel < 2;
Builder.populateFunctionPassManager(FPM);
Builder.populateModulePassManager(MPM);
}
static void AddStandardLinkPasses(legacy::PassManagerBase &PM) {
PassManagerBuilder Builder;
Builder.VerifyInput = true;
if (DisableOptimizations)
Builder.OptLevel = 0;
if (!DisableInline)
Builder.Inliner = createFunctionInliningPass();
Builder.populateLTOPassManager(PM);
}
//===----------------------------------------------------------------------===//
// CodeGen-related helper functions.
//
static CodeGenOpt::Level GetCodeGenOptLevel() {
if (OptLevelO1)
return CodeGenOpt::Less;
if (OptLevelO2)
return CodeGenOpt::Default;
if (OptLevelO3)
return CodeGenOpt::Aggressive;
return CodeGenOpt::None;
}
// Returns the TargetMachine instance or zero if no triple is provided.
static TargetMachine* GetTargetMachine(Triple TheTriple, StringRef CPUStr,
StringRef FeaturesStr,
const TargetOptions &Options) {
std::string Error;
const Target *TheTarget = TargetRegistry::lookupTarget(MArch, TheTriple,
Error);
// Some modules don't specify a triple, and this is okay.
if (!TheTarget) {
return nullptr;
}
return TheTarget->createTargetMachine(TheTriple.getTriple(),
CPUStr, FeaturesStr, Options,
RelocModel, CMModel,
GetCodeGenOptLevel());
}
#ifdef LINK_POLLY_INTO_TOOLS
namespace polly {
void initializePollyPasses(llvm::PassRegistry &Registry);
}
#endif
//===----------------------------------------------------------------------===//
// main for opt
//
int main(int argc, char **argv) {
sys::PrintStackTraceOnErrorSignal();
llvm::PrettyStackTraceProgram X(argc, argv);
// Enable debug stream buffering.
EnableDebugBuffering = true;
llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
LLVMContext &Context = getGlobalContext();
InitializeAllTargets();
InitializeAllTargetMCs();
InitializeAllAsmPrinters();
// Initialize passes
PassRegistry &Registry = *PassRegistry::getPassRegistry();
initializeCore(Registry);
initializeScalarOpts(Registry);
initializeObjCARCOpts(Registry);
initializeVectorization(Registry);
initializeIPO(Registry);
initializeAnalysis(Registry);
initializeTransformUtils(Registry);
initializeInstCombine(Registry);
initializeInstrumentation(Registry);
initializeTarget(Registry);
// For codegen passes, only passes that do IR to IR transformation are
// supported.
initializeCodeGenPreparePass(Registry);
initializeAtomicExpandPass(Registry);
initializeRewriteSymbolsPass(Registry);
initializeWinEHPreparePass(Registry);
initializeDwarfEHPreparePass(Registry);
initializeSjLjEHPreparePass(Registry);
#ifdef LINK_POLLY_INTO_TOOLS
polly::initializePollyPasses(Registry);
#endif
cl::ParseCommandLineOptions(argc, argv,
"llvm .bc -> .bc modular optimizer and analysis printer\n");
if (AnalyzeOnly && NoOutput) {
errs() << argv[0] << ": analyze mode conflicts with no-output mode.\n";
return 1;
}
SMDiagnostic Err;
// Load the input module...
std::unique_ptr<Module> M;
// XXX EMSCRIPTEN: support for multiple files
if (InputFilenames.size() == 0)
M = parseIRFile("-", Err, Context);
else if (InputFilenames.size() == 1)
M = parseIRFile(InputFilenames[0], Err, Context);
else {
// link them in
M = nullptr;
std::unique_ptr<Linker> L;
for (unsigned i = 0; i < InputFilenames.size(); ++i) {
std::unique_ptr<Module> MM = parseIRFile(InputFilenames[i], Err, Context);
if (!MM.get()) {
errs() << argv[0] << ": error loading file '" <<InputFilenames[i]<< "'\n";
return 1;
}
if (!NoVerify && verifyModule(*MM, &errs())) {
errs() << argv[0] << ": " << InputFilenames[i]
<< ": error: input module is broken!\n";
return 1;
}
if (i == 0) {
M.swap(MM);
L = make_unique<Linker>(*M);
} else {
if (L->linkInModule(std::move(MM)))
return 1;
}
}
}
if (!M) {
Err.print(argv[0], errs());
return 1;
}
// Strip debug info before running the verifier.
if (StripDebug)
StripDebugInfo(*M);
// Immediately run the verifier to catch any problems before starting up the
// pass pipelines. Otherwise we can crash on broken code during
// doInitialization().
if (!NoVerify && verifyModule(*M, &errs())) {
errs() << argv[0] << ": "
<< ": error: input module is broken!\n";
return 1;
}
// If we are supposed to override the target triple, do so now.
if (!TargetTriple.empty())
M->setTargetTriple(Triple::normalize(TargetTriple));
// Figure out what stream we are supposed to write to...
std::unique_ptr<tool_output_file> Out;
if (NoOutput) {
if (!OutputFilename.empty())
errs() << "WARNING: The -o (output filename) option is ignored when\n"
"the --disable-output option is used.\n";
} else {
// Default to standard output.
if (OutputFilename.empty())
OutputFilename = "-";
std::error_code EC;
Out.reset(new tool_output_file(OutputFilename, EC, sys::fs::F_None));
if (EC) {
errs() << EC.message() << '\n';
return 1;
}
}
Triple ModuleTriple(M->getTargetTriple());
std::string CPUStr, FeaturesStr;
TargetMachine *Machine = nullptr;
const TargetOptions Options = InitTargetOptionsFromCodeGenFlags();
if (ModuleTriple.getArch()) {
CPUStr = getCPUStr();
FeaturesStr = getFeaturesStr();
Machine = GetTargetMachine(ModuleTriple, CPUStr, FeaturesStr, Options);
}
std::unique_ptr<TargetMachine> TM(Machine);
// Override function attributes based on CPUStr, FeaturesStr, and command line
// flags.
setFunctionAttributes(CPUStr, FeaturesStr, *M);
// If the output is set to be emitted to standard out, and standard out is a
// console, print out a warning message and refuse to do it. We don't
// impress anyone by spewing tons of binary goo to a terminal.
if (!Force && !NoOutput && !AnalyzeOnly && !OutputAssembly)
if (CheckBitcodeOutputToConsole(Out->os(), !Quiet))
NoOutput = true;
if (PassPipeline.getNumOccurrences() > 0) {
OutputKind OK = OK_NoOutput;
if (!NoOutput)
OK = OutputAssembly ? OK_OutputAssembly : OK_OutputBitcode;
VerifierKind VK = VK_VerifyInAndOut;
if (NoVerify)
VK = VK_NoVerifier;
else if (VerifyEach)
VK = VK_VerifyEachPass;
// The user has asked to use the new pass manager and provided a pipeline
// string. Hand off the rest of the functionality to the new code for that
// layer.
return runPassPipeline(argv[0], Context, *M, TM.get(), Out.get(),
PassPipeline, OK, VK, PreserveAssemblyUseListOrder,
PreserveBitcodeUseListOrder)
? 0
: 1;
}
// Create a PassManager to hold and optimize the collection of passes we are
// about to build.
//
legacy::PassManager Passes;
// Add an appropriate TargetLibraryInfo pass for the module's triple.
TargetLibraryInfoImpl TLII(ModuleTriple);
// The -disable-simplify-libcalls flag actually disables all builtin optzns.
if (DisableSimplifyLibCalls)
TLII.disableAllFunctions();
Passes.add(new TargetLibraryInfoWrapperPass(TLII));
// Add an appropriate DataLayout instance for this module.
const DataLayout &DL = M->getDataLayout();
if (DL.isDefault() && !DefaultDataLayout.empty()) {
M->setDataLayout(DefaultDataLayout);
}
// Add internal analysis passes from the target machine.
Passes.add(createTargetTransformInfoWrapperPass(TM ? TM->getTargetIRAnalysis()
: TargetIRAnalysis()));
std::unique_ptr<legacy::FunctionPassManager> FPasses;
if (OptLevelO1 || OptLevelO2 || OptLevelOs || OptLevelOz || OptLevelO3) {
FPasses.reset(new legacy::FunctionPassManager(M.get()));
FPasses->add(createTargetTransformInfoWrapperPass(
TM ? TM->getTargetIRAnalysis() : TargetIRAnalysis()));
}
if (PrintBreakpoints) {
// Default to standard output.
if (!Out) {
if (OutputFilename.empty())
OutputFilename = "-";
std::error_code EC;
Out = llvm::make_unique<tool_output_file>(OutputFilename, EC,
sys::fs::F_None);
if (EC) {
errs() << EC.message() << '\n';
return 1;
}
}
Passes.add(createBreakpointPrinter(Out->os()));
NoOutput = true;
}
// Create a new optimization pass for each one specified on the command line
for (unsigned i = 0; i < PassList.size(); ++i) {
if (StandardLinkOpts &&
StandardLinkOpts.getPosition() < PassList.getPosition(i)) {
AddStandardLinkPasses(Passes);
StandardLinkOpts = false;
}
if (OptLevelO1 && OptLevelO1.getPosition() < PassList.getPosition(i)) {
AddOptimizationPasses(Passes, *FPasses, 1, 0);
OptLevelO1 = false;
}
if (OptLevelO2 && OptLevelO2.getPosition() < PassList.getPosition(i)) {
AddOptimizationPasses(Passes, *FPasses, 2, 0);
OptLevelO2 = false;
}
if (OptLevelOs && OptLevelOs.getPosition() < PassList.getPosition(i)) {
AddOptimizationPasses(Passes, *FPasses, 2, 1);
OptLevelOs = false;
}
if (OptLevelOz && OptLevelOz.getPosition() < PassList.getPosition(i)) {
AddOptimizationPasses(Passes, *FPasses, 2, 2);
OptLevelOz = false;
}
if (OptLevelO3 && OptLevelO3.getPosition() < PassList.getPosition(i)) {
AddOptimizationPasses(Passes, *FPasses, 3, 0);
OptLevelO3 = false;
}
const PassInfo *PassInf = PassList[i];
Pass *P = nullptr;
if (PassInf->getTargetMachineCtor())
P = PassInf->getTargetMachineCtor()(TM.get());
else if (PassInf->getNormalCtor())
P = PassInf->getNormalCtor()();
else
errs() << argv[0] << ": cannot create pass: "
<< PassInf->getPassName() << "\n";
if (P) {
PassKind Kind = P->getPassKind();
addPass(Passes, P);
if (AnalyzeOnly) {
switch (Kind) {
case PT_BasicBlock:
Passes.add(createBasicBlockPassPrinter(PassInf, Out->os(), Quiet));
break;
case PT_Region:
Passes.add(createRegionPassPrinter(PassInf, Out->os(), Quiet));
break;
case PT_Loop:
Passes.add(createLoopPassPrinter(PassInf, Out->os(), Quiet));
break;
case PT_Function:
Passes.add(createFunctionPassPrinter(PassInf, Out->os(), Quiet));
break;
case PT_CallGraphSCC:
Passes.add(createCallGraphPassPrinter(PassInf, Out->os(), Quiet));
break;
default:
Passes.add(createModulePassPrinter(PassInf, Out->os(), Quiet));
break;
}
}
}
if (PrintEachXForm)
Passes.add(
createPrintModulePass(errs(), "", PreserveAssemblyUseListOrder));
}
if (StandardLinkOpts) {
AddStandardLinkPasses(Passes);
StandardLinkOpts = false;
}
if (OptLevelO1)
AddOptimizationPasses(Passes, *FPasses, 1, 0);
if (OptLevelO2)
AddOptimizationPasses(Passes, *FPasses, 2, 0);
if (OptLevelOs)
AddOptimizationPasses(Passes, *FPasses, 2, 1);
if (OptLevelOz)
AddOptimizationPasses(Passes, *FPasses, 2, 2);
if (OptLevelO3)
AddOptimizationPasses(Passes, *FPasses, 3, 0);
if (OptLevelO1 || OptLevelO2 || OptLevelOs || OptLevelOz || OptLevelO3) {
FPasses->doInitialization();
for (Function &F : *M)
FPasses->run(F);
FPasses->doFinalization();
}
// Check that the module is well formed on completion of optimization
if (!NoVerify && !VerifyEach)
Passes.add(createVerifierPass());
// In run twice mode, we want to make sure the output is bit-by-bit
// equivalent if we run the pass manager again, so setup two buffers and
// a stream to write to them. Note that llc does something similar and it
// may be worth to abstract this out in the future.
SmallVector<char, 0> Buffer;
SmallVector<char, 0> CompileTwiceBuffer;
std::unique_ptr<raw_svector_ostream> BOS;
raw_ostream *OS = nullptr;
// Write bitcode or assembly to the output as the last step...
if (!NoOutput && !AnalyzeOnly) {
assert(Out);
OS = &Out->os();
if (RunTwice) {
BOS = make_unique<raw_svector_ostream>(Buffer);
OS = BOS.get();
}
if (OutputAssembly)
Passes.add(createPrintModulePass(*OS, "", PreserveAssemblyUseListOrder));
else
Passes.add(createBitcodeWriterPass(*OS, PreserveBitcodeUseListOrder));
}
// Before executing passes, print the final values of the LLVM options.
cl::PrintOptionValues();
// If requested, run all passes again with the same pass manager to catch
// bugs caused by persistent state in the passes
if (RunTwice) {
std::unique_ptr<Module> M2(CloneModule(M.get()));
Passes.run(*M2);
CompileTwiceBuffer = Buffer;
Buffer.clear();
}
// Now that we have all of the passes ready, run them.
Passes.run(*M);
// Compare the two outputs and make sure they're the same
if (RunTwice) {
assert(Out);
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() << BOS->str();
Out->keep();
return 1;
}
Out->os() << BOS->str();
}
// Declare success.
if (!NoOutput || PrintBreakpoints)
Out->keep();
return 0;
}