From e4292bf08660b2e945d68dd7c9918620ec25cf8a Mon Sep 17 00:00:00 2001 From: Michael Kruse Date: Thu, 9 Mar 2017 22:29:58 +0000 Subject: [PATCH] [Support] Add -polly-dump-module pass. This pass allows writing the LLVM-IR just before and after the Polly passes to a file. Dumping the IR before Polly helps reproducing bugs that occur in code generated by clang. It is the only reliable way to get the IR that triggers a bug. The alternative is to emit the IR with clang -c -emit-llvm -S -o dump.ll then pass it through all optimization passes opt dump.ll -basicaa -sroa ... -S -o optdump.ll to then reproduce the error with opt optdump.ll -polly-opt-isl -polly-codegen -analyze However, the IR is not the same. -O3 uses a PassBuilder than creates passes with different parameters than the default. Dumping the IR after Polly is useful to compare a miscompilation with a known-good configuration. Differential Revision: https://reviews.llvm.org/D30788 llvm-svn: 297415 --- polly/include/polly/LinkAllPasses.h | 3 + polly/include/polly/Support/DumpModulePass.h | 40 +++++++++ polly/lib/CMakeLists.txt | 1 + polly/lib/Support/DumpModulePass.cpp | 95 ++++++++++++++++++++ polly/lib/Support/RegisterPasses.cpp | 34 +++++++ 5 files changed, 173 insertions(+) create mode 100644 polly/include/polly/Support/DumpModulePass.h create mode 100644 polly/lib/Support/DumpModulePass.cpp diff --git a/polly/include/polly/LinkAllPasses.h b/polly/include/polly/LinkAllPasses.h index 6f0dd1ca0553..d43528b698a9 100644 --- a/polly/include/polly/LinkAllPasses.h +++ b/polly/include/polly/LinkAllPasses.h @@ -16,6 +16,8 @@ #define POLLY_LINKALLPASSES_H #include "polly/Config/config.h" +#include "polly/Support/DumpModulePass.h" +#include "llvm/ADT/StringRef.h" #include namespace llvm { @@ -84,6 +86,7 @@ struct PollyForcePassLinking { polly::createIslScheduleOptimizerPass(); polly::createFlattenSchedulePass(); polly::createDeLICMPass(); + polly::createDumpModulePass("", true); } } PollyForcePassLinking; // Force link by creating a global definition. } // namespace diff --git a/polly/include/polly/Support/DumpModulePass.h b/polly/include/polly/Support/DumpModulePass.h new file mode 100644 index 000000000000..1da94ba7fa13 --- /dev/null +++ b/polly/include/polly/Support/DumpModulePass.h @@ -0,0 +1,40 @@ +//===------ DumpModulePass.cpp ----------------------------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// Write a module to a file. +// +//===----------------------------------------------------------------------===// + +#ifndef POLLY_SUPPORT_DUMPMODULEPASS_H +#define POLLY_SUPPORT_DUMPMODULEPASS_H + +namespace llvm { +class StringRef; +class ModulePass; +} // namespace llvm + +namespace polly { +/// Create a pass that prints the module into a file. +/// +/// The meaning of @p Filename depends on @p IsSuffix. If IsSuffix==false, then +/// the module is written to the @p Filename. If it is true, the filename is +/// generated from the module's name, @p Filename with an '.ll' extension. +/// +/// The intent of IsSuffix is to avoid the file being overwritten when +/// processing multiple modules and/or with multiple dump passes in the +/// pipeline. +llvm::ModulePass *createDumpModulePass(llvm::StringRef Filename, bool IsSuffix); +} // namespace polly + +namespace llvm { +class PassRegistry; +void initializeDumpModulePass(llvm::PassRegistry &); +} // namespace llvm + +#endif /* POLLY_SUPPORT_DUMPMODULEPASS_H */ diff --git a/polly/lib/CMakeLists.txt b/polly/lib/CMakeLists.txt index abe6397eead8..d3088fdcf7c5 100644 --- a/polly/lib/CMakeLists.txt +++ b/polly/lib/CMakeLists.txt @@ -51,6 +51,7 @@ add_polly_library(Polly Support/ScopHelper.cpp Support/ScopLocation.cpp Support/ISLTools.cpp + Support/DumpModulePass.cpp ${POLLY_JSON_FILES} Transform/Canonicalization.cpp Transform/CodePreparation.cpp diff --git a/polly/lib/Support/DumpModulePass.cpp b/polly/lib/Support/DumpModulePass.cpp new file mode 100644 index 000000000000..558088cf898a --- /dev/null +++ b/polly/lib/Support/DumpModulePass.cpp @@ -0,0 +1,95 @@ +//===------ DumpModulePass.cpp ----------------------------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// Write a module to a file. +// +//===----------------------------------------------------------------------===// + +#include "polly/Support/DumpModulePass.h" + +#include "polly/Options.h" +#include "llvm/IR/LegacyPassManagers.h" +#include "llvm/IR/Module.h" +#include "llvm/Pass.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/FileSystem.h" +#include "llvm/Support/Path.h" +#include "llvm/Support/ToolOutputFile.h" +#include +#define DEBUG_TYPE "polly-dump-module" + +using namespace llvm; +using namespace polly; + +namespace { + +class DumpModule : public ModulePass { +private: + DumpModule(const DumpModule &) = delete; + const DumpModule &operator=(const DumpModule &) = delete; + + std::string Filename; + bool IsSuffix; + +public: + static char ID; + + /// This constructor is used e.g. if using opt -polly-dump-module. + /// + /// Provide a default suffix to not overwrite the original file. + explicit DumpModule() : ModulePass(ID), Filename("-dump"), IsSuffix(true) {} + + explicit DumpModule(llvm::StringRef Filename, bool IsSuffix) + : ModulePass(ID), Filename(Filename), IsSuffix(IsSuffix) {} + + /// @name ModulePass interface + //@{ + virtual void getAnalysisUsage(llvm::AnalysisUsage &AU) const override { + AU.setPreservesAll(); + } + + virtual bool runOnModule(llvm::Module &M) override { + std::string Dumpfile; + if (IsSuffix) { + auto ModuleName = M.getName(); + auto Stem = sys::path::stem(ModuleName); + Dumpfile = (Twine(Stem) + Filename + ".ll").str(); + } else { + Dumpfile = Filename; + } + DEBUG(dbgs() << "Dumping module to " << Dumpfile << '\n'); + + std::unique_ptr Out; + std::error_code EC; + Out.reset(new tool_output_file(Dumpfile, EC, sys::fs::F_None)); + if (EC) { + errs() << EC.message() << '\n'; + return false; + } + + M.print(Out->os(), nullptr); + Out->keep(); + + return false; + } + //@} +}; + +char DumpModule::ID; +} // namespace + +ModulePass *polly::createDumpModulePass(llvm::StringRef Filename, + bool IsSuffix) { + return new DumpModule(Filename, IsSuffix); +} + +INITIALIZE_PASS_BEGIN(DumpModule, "polly-dump-module", "Polly - Dump Module", + false, false) +INITIALIZE_PASS_END(DumpModule, "polly-dump-module", "Polly - Dump Module", + false, false) diff --git a/polly/lib/Support/RegisterPasses.cpp b/polly/lib/Support/RegisterPasses.cpp index 949328962f05..703cbe2ae1f5 100644 --- a/polly/lib/Support/RegisterPasses.cpp +++ b/polly/lib/Support/RegisterPasses.cpp @@ -31,6 +31,7 @@ #include "polly/PolyhedralInfo.h" #include "polly/ScopDetection.h" #include "polly/ScopInfo.h" +#include "polly/Support/DumpModulePass.h" #include "llvm/Analysis/CFGPrinter.h" #include "llvm/IR/LegacyPassManager.h" #include "llvm/Transforms/IPO.h" @@ -160,6 +161,28 @@ static cl::opt cl::desc("Enable polyhedral interface of Polly"), cl::Hidden, cl::init(false), cl::cat(PollyCategory)); +static cl::opt + DumpBefore("polly-dump-before", + cl::desc("Dump module before Polly transformations into a file " + "suffixed with \"-before\""), + cl::init(false), cl::cat(PollyCategory)); + +static cl::list DumpBeforeFile( + "polly-dump-before-file", + cl::desc("Dump module before Polly transformations to the given file"), + cl::cat(PollyCategory)); + +static cl::opt + DumpAfter("polly-dump-after", + cl::desc("Dump module after Polly transformations into a file " + "suffixed with \"-after\""), + cl::init(false), cl::cat(PollyCategory)); + +static cl::list DumpAfterFile( + "polly-dump-after-file", + cl::desc("Dump module after Polly transformations to the given file"), + cl::ZeroOrMore, cl::cat(PollyCategory)); + static cl::opt EnableDeLICM("polly-enable-delicm", cl::desc("Eliminate scalar loop carried dependences"), @@ -188,6 +211,7 @@ void initializePollyPasses(PassRegistry &Registry) { initializeCodegenCleanupPass(Registry); initializeFlattenSchedulePass(Registry); initializeDeLICMPass(Registry); + initializeDumpModulePass(Registry); } /// Register Polly passes such that they form a polyhedral optimizer. @@ -217,6 +241,11 @@ void initializePollyPasses(PassRegistry &Registry) { /// /// Polly supports the isl internal code generator. void registerPollyPasses(llvm::legacy::PassManagerBase &PM) { + if (DumpBefore) + PM.add(polly::createDumpModulePass("-before", true)); + for (auto &Filename : DumpBeforeFile) + PM.add(polly::createDumpModulePass(Filename, false)); + PM.add(polly::createScopDetectionPass()); if (PollyDetectOnly) @@ -282,6 +311,11 @@ void registerPollyPasses(llvm::legacy::PassManagerBase &PM) { // force all analysis results to be recomputed. PM.add(createBarrierNoopPass()); + if (DumpAfter) + PM.add(polly::createDumpModulePass("-after", true)); + for (auto &Filename : DumpAfterFile) + PM.add(polly::createDumpModulePass(Filename, false)); + if (CFGPrinter) PM.add(llvm::createCFGPrinterLegacyPassPass());