--- /dev/null
+//===-- llvm/CodeGen/ParallelCG.h - Parallel code generation ----*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This header declares functions that can be used for parallel code generation.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_PARALLELCG_H
+#define LLVM_CODEGEN_PARALLELCG_H
+
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/Support/CodeGen.h"
+
+namespace llvm {
+
+class Module;
+class TargetOptions;
+class raw_pwrite_stream;
+
+/// Split M into OSs.size() partitions, and generate code for each. Writes
+/// OSs.size() object files to the output streams in OSs. The resulting object
+/// files if linked together are intended to be equivalent to the single object
+/// file that would have been code generated from M.
+///
+/// \returns M if OSs.size() == 1, otherwise returns std::unique_ptr<Module>().
+std::unique_ptr<Module>
+splitCodeGen(std::unique_ptr<Module> M, ArrayRef<raw_pwrite_stream *> OSs,
+ StringRef CPU, StringRef Features, const TargetOptions &Options,
+ Reloc::Model RM = Reloc::Default,
+ CodeModel::Model CM = CodeModel::Default,
+ CodeGenOpt::Level OL = CodeGenOpt::Default);
+
+} // namespace llvm
+
+#endif
// if the compilation was not successful.
std::unique_ptr<MemoryBuffer> compileOptimized(std::string &errMsg);
+ // Compile the merged optimized module into out.size() object files each
+ // representing a linkable partition of the module. If out contains more than
+ // one element, code generation is done in parallel with out.size() threads.
+ // Object files will be written to members of out. Returns true on success.
+ bool compileOptimized(ArrayRef<raw_pwrite_stream *> out, std::string &errMsg);
+
void setDiagnosticHandler(lto_diagnostic_handler_t, void *);
LLVMContext &getContext() { return Context; }
private:
void initializeLTOPasses();
- bool compileOptimized(raw_pwrite_stream &out, std::string &errMsg);
bool compileOptimizedToFile(const char **name, std::string &errMsg);
void applyScopeRestrictions();
void applyRestriction(GlobalValue &GV, ArrayRef<StringRef> Libcalls,
OptimizePHIs.cpp
PHIElimination.cpp
PHIEliminationUtils.cpp
+ ParallelCG.cpp
Passes.cpp
PeepholeOptimizer.cpp
PostRASchedulerList.cpp
--- /dev/null
+//===-- ParallelCG.cpp ----------------------------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines functions that can be used for parallel code generation.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/ParallelCG.h"
+#include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/LegacyPassManager.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/ErrorOr.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/Support/thread.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Transforms/Utils/SplitModule.h"
+
+using namespace llvm;
+
+static void codegen(Module *M, llvm::raw_pwrite_stream &OS,
+ const Target *TheTarget, StringRef CPU, StringRef Features,
+ const TargetOptions &Options, Reloc::Model RM,
+ CodeModel::Model CM, CodeGenOpt::Level OL) {
+ std::unique_ptr<TargetMachine> TM(TheTarget->createTargetMachine(
+ M->getTargetTriple(), CPU, Features, Options, RM, CM, OL));
+
+ legacy::PassManager CodeGenPasses;
+ if (TM->addPassesToEmitFile(CodeGenPasses, OS,
+ TargetMachine::CGFT_ObjectFile))
+ report_fatal_error("Failed to setup codegen");
+ CodeGenPasses.run(*M);
+}
+
+std::unique_ptr<Module>
+llvm::splitCodeGen(std::unique_ptr<Module> M,
+ ArrayRef<llvm::raw_pwrite_stream *> OSs, StringRef CPU,
+ StringRef Features, const TargetOptions &Options,
+ Reloc::Model RM, CodeModel::Model CM, CodeGenOpt::Level OL) {
+ StringRef TripleStr = M->getTargetTriple();
+ std::string ErrMsg;
+ const Target *TheTarget = TargetRegistry::lookupTarget(TripleStr, ErrMsg);
+ if (!TheTarget)
+ report_fatal_error(Twine("Target not found: ") + ErrMsg);
+
+ if (OSs.size() == 1) {
+ codegen(M.get(), *OSs[0], TheTarget, CPU, Features, Options, RM, CM,
+ OL);
+ return M;
+ }
+
+ std::vector<std::thread> Threads;
+ SplitModule(std::move(M), OSs.size(), [&](std::unique_ptr<Module> MPart) {
+ // We want to clone the module in a new context to multi-thread the codegen.
+ // We do it by serializing partition modules to bitcode (while still on the
+ // main thread, in order to avoid data races) and spinning up new threads
+ // which deserialize the partitions into separate contexts.
+ // FIXME: Provide a more direct way to do this in LLVM.
+ SmallVector<char, 0> BC;
+ raw_svector_ostream BCOS(BC);
+ WriteBitcodeToFile(MPart.get(), BCOS);
+
+ llvm::raw_pwrite_stream *ThreadOS = OSs[Threads.size()];
+ Threads.emplace_back(
+ [TheTarget, CPU, Features, Options, RM, CM, OL,
+ ThreadOS](const SmallVector<char, 0> &BC) {
+ LLVMContext Ctx;
+ ErrorOr<std::unique_ptr<Module>> MOrErr =
+ parseBitcodeFile(MemoryBufferRef(StringRef(BC.data(), BC.size()),
+ "<split-module>"),
+ Ctx);
+ if (!MOrErr)
+ report_fatal_error("Failed to read bitcode");
+ std::unique_ptr<Module> MPartInCtx = std::move(MOrErr.get());
+
+ codegen(MPartInCtx.get(), *ThreadOS, TheTarget, CPU, Features,
+ Options, RM, CM, OL);
+ },
+ // Pass BC using std::move to ensure that it get moved rather than
+ // copied into the thread's context.
+ std::move(BC));
+ });
+
+ for (std::thread &T : Threads)
+ T.join();
+
+ return {};
+}
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/CodeGen/ParallelCG.h"
#include "llvm/CodeGen/RuntimeLibcalls.h"
#include "llvm/Config/config.h"
#include "llvm/IR/Constants.h"
// generate object file
tool_output_file objFile(Filename.c_str(), FD);
- bool genResult = compileOptimized(objFile.os(), errMsg);
+ bool genResult = compileOptimized(&objFile.os(), errMsg);
objFile.os().close();
if (objFile.os().has_error()) {
objFile.os().clear_error();
return true;
}
-bool LTOCodeGenerator::compileOptimized(raw_pwrite_stream &out,
+bool LTOCodeGenerator::compileOptimized(ArrayRef<raw_pwrite_stream *> out,
std::string &errMsg) {
if (!this->determineTarget(errMsg))
return false;
- legacy::PassManager codeGenPasses;
+ legacy::PassManager preCodeGenPasses;
// If the bitcode files contain ARC code and were compiled with optimization,
// the ObjCARCContractPass must be run, so do it unconditionally here.
- codeGenPasses.add(createObjCARCContractPass());
-
- if (TargetMach->addPassesToEmitFile(codeGenPasses, out,
- TargetMachine::CGFT_ObjectFile)) {
- errMsg = "target file type not supported";
- return false;
- }
-
- // Run the code generator, and write object file
- codeGenPasses.run(*MergedModule);
+ preCodeGenPasses.add(createObjCARCContractPass());
+ preCodeGenPasses.run(*MergedModule);
+
+ // Do code generation. We need to preserve the module in case the client calls
+ // writeMergedModules() after compilation, but we only need to allow this at
+ // parallelism level 1. This is achieved by having splitCodeGen return the
+ // original module at parallelism level 1 which we then assign back to
+ // MergedModule.
+ MergedModule =
+ splitCodeGen(std::move(MergedModule), out, MCpu, FeatureStr, Options,
+ RelocModel, CodeModel::Default, CGOptLevel);
return true;
}
--- /dev/null
+; RUN: llvm-as -o %t.bc %s
+; RUN: llvm-lto -exported-symbol=foo -exported-symbol=bar -j2 -o %t.o %t.bc
+; RUN: llvm-nm %t.o.0 | FileCheck --check-prefix=CHECK0 %s
+; RUN: llvm-nm %t.o.1 | FileCheck --check-prefix=CHECK1 %s
+
+target triple = "x86_64-unknown-linux-gnu"
+
+; CHECK0-NOT: bar
+; CHECK0: T foo
+; CHECK0-NOT: bar
+define void @foo() {
+ call void @bar()
+ ret void
+}
+
+; CHECK1-NOT: foo
+; CHECK1: T bar
+; CHECK1-NOT: foo
+define void @bar() {
+ call void @foo()
+ ret void
+}
#include "llvm/Support/PrettyStackTrace.h"
#include "llvm/Support/Signals.h"
#include "llvm/Support/TargetSelect.h"
+#include "llvm/Support/ToolOutputFile.h"
#include "llvm/Support/raw_ostream.h"
+#include <list>
using namespace llvm;
"set-merged-module", cl::init(false),
cl::desc("Use the first input module as the merged module"));
+static cl::opt<unsigned> Parallelism("j", cl::Prefix, cl::init(1),
+ cl::desc("Number of backend threads"));
+
namespace {
struct ModuleInfo {
std::vector<bool> CanBeHidden;
if (!OutputFilename.empty()) {
std::string ErrorInfo;
- std::unique_ptr<MemoryBuffer> Code = CodeGen.compile(
- DisableInline, DisableGVNLoadPRE, DisableLTOVectorization, ErrorInfo);
- if (!Code) {
- errs() << argv[0]
- << ": error compiling the code: " << ErrorInfo << "\n";
+ if (!CodeGen.optimize(DisableInline, DisableGVNLoadPRE,
+ DisableLTOVectorization, ErrorInfo)) {
+ errs() << argv[0] << ": error optimizing the code: " << ErrorInfo << "\n";
return 1;
}
- std::error_code EC;
- raw_fd_ostream FileStream(OutputFilename, EC, sys::fs::F_None);
- if (EC) {
- errs() << argv[0] << ": error opening the file '" << OutputFilename
- << "': " << EC.message() << "\n";
+ std::list<tool_output_file> OSs;
+ std::vector<raw_pwrite_stream *> OSPtrs;
+ for (unsigned I = 0; I != Parallelism; ++I) {
+ std::string PartFilename = OutputFilename;
+ if (Parallelism != 1)
+ PartFilename += "." + utostr(I);
+ std::error_code EC;
+ OSs.emplace_back(PartFilename, EC, sys::fs::F_None);
+ if (EC) {
+ errs() << argv[0] << ": error opening the file '" << PartFilename
+ << "': " << EC.message() << "\n";
+ return 1;
+ }
+ OSPtrs.push_back(&OSs.back().os());
+ }
+
+ if (!CodeGen.compileOptimized(OSPtrs, ErrorInfo)) {
+ errs() << argv[0] << ": error compiling the code: " << ErrorInfo << "\n";
return 1;
}
- FileStream.write(Code->getBufferStart(), Code->getBufferSize());
+ for (tool_output_file &OS : OSs)
+ OS.keep();
} else {
+ if (Parallelism != 1) {
+ errs() << argv[0] << ": -j must be specified together with -o\n";
+ return 1;
+ }
+
std::string ErrorInfo;
const char *OutputName = nullptr;
if (!CodeGen.compile_to_file(&OutputName, DisableInline,