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Diffstat (limited to 'tools/llvm-lto/llvm-lto.cpp')
-rw-r--r-- | tools/llvm-lto/llvm-lto.cpp | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/tools/llvm-lto/llvm-lto.cpp b/tools/llvm-lto/llvm-lto.cpp new file mode 100644 index 0000000..0fc68ae --- /dev/null +++ b/tools/llvm-lto/llvm-lto.cpp @@ -0,0 +1,187 @@ +//===-- llvm-lto: a simple command-line program to link modules with LTO --===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This program takes in a list of bitcode files, links them, performs link-time +// optimization, and outputs an object file. +// +//===----------------------------------------------------------------------===// + +#include "llvm/ADT/StringSet.h" +#include "llvm/CodeGen/CommandFlags.h" +#include "llvm/LTO/LTOCodeGenerator.h" +#include "llvm/LTO/LTOModule.h" +#include "llvm/Support/CommandLine.h" +#include "llvm/Support/ManagedStatic.h" +#include "llvm/Support/PrettyStackTrace.h" +#include "llvm/Support/Signals.h" +#include "llvm/Support/raw_ostream.h" +#include "llvm/Support/TargetSelect.h" + +using namespace llvm; + +static cl::opt<bool> +DisableOpt("disable-opt", cl::init(false), + cl::desc("Do not run any optimization passes")); + +static cl::opt<bool> +DisableInline("disable-inlining", cl::init(false), + cl::desc("Do not run the inliner pass")); + +static cl::opt<bool> +DisableGVNLoadPRE("disable-gvn-loadpre", cl::init(false), + cl::desc("Do not run the GVN load PRE pass")); + +static cl::list<std::string> +InputFilenames(cl::Positional, cl::OneOrMore, + cl::desc("<input bitcode files>")); + +static cl::opt<std::string> +OutputFilename("o", cl::init(""), + cl::desc("Override output filename"), + cl::value_desc("filename")); + +static cl::list<std::string> +ExportedSymbols("exported-symbol", + cl::desc("Symbol to export from the resulting object file"), + cl::ZeroOrMore); + +static cl::list<std::string> +DSOSymbols("dso-symbol", + cl::desc("Symbol to put in the symtab in the resulting dso"), + cl::ZeroOrMore); + +namespace { +struct ModuleInfo { + std::vector<bool> CanBeHidden; +}; +} + +int main(int argc, char **argv) { + // Print a stack trace if we signal out. + sys::PrintStackTraceOnErrorSignal(); + PrettyStackTraceProgram X(argc, argv); + + llvm_shutdown_obj Y; // Call llvm_shutdown() on exit. + cl::ParseCommandLineOptions(argc, argv, "llvm LTO linker\n"); + + // Initialize the configured targets. + InitializeAllTargets(); + InitializeAllTargetMCs(); + InitializeAllAsmPrinters(); + InitializeAllAsmParsers(); + + // set up the TargetOptions for the machine + TargetOptions Options; + Options.LessPreciseFPMADOption = EnableFPMAD; + Options.NoFramePointerElim = DisableFPElim; + Options.AllowFPOpFusion = FuseFPOps; + Options.UnsafeFPMath = EnableUnsafeFPMath; + Options.NoInfsFPMath = EnableNoInfsFPMath; + Options.NoNaNsFPMath = EnableNoNaNsFPMath; + Options.HonorSignDependentRoundingFPMathOption = + EnableHonorSignDependentRoundingFPMath; + Options.UseSoftFloat = GenerateSoftFloatCalls; + if (FloatABIForCalls != FloatABI::Default) + Options.FloatABIType = FloatABIForCalls; + Options.NoZerosInBSS = DontPlaceZerosInBSS; + Options.GuaranteedTailCallOpt = EnableGuaranteedTailCallOpt; + Options.DisableTailCalls = DisableTailCalls; + Options.StackAlignmentOverride = OverrideStackAlignment; + Options.TrapFuncName = TrapFuncName; + Options.PositionIndependentExecutable = EnablePIE; + Options.EnableSegmentedStacks = SegmentedStacks; + Options.UseInitArray = UseInitArray; + + unsigned BaseArg = 0; + + LTOCodeGenerator CodeGen; + + CodeGen.setCodePICModel(LTO_CODEGEN_PIC_MODEL_DYNAMIC); + CodeGen.setDebugInfo(LTO_DEBUG_MODEL_DWARF); + CodeGen.setTargetOptions(Options); + + llvm::StringSet<llvm::MallocAllocator> DSOSymbolsSet; + for (unsigned i = 0; i < DSOSymbols.size(); ++i) + DSOSymbolsSet.insert(DSOSymbols[i]); + + std::vector<std::string> KeptDSOSyms; + + for (unsigned i = BaseArg; i < InputFilenames.size(); ++i) { + std::string error; + OwningPtr<LTOModule> Module(LTOModule::makeLTOModule(InputFilenames[i].c_str(), + Options, error)); + if (!error.empty()) { + errs() << argv[0] << ": error loading file '" << InputFilenames[i] + << "': " << error << "\n"; + return 1; + } + + + if (!CodeGen.addModule(Module.get(), error)) { + errs() << argv[0] << ": error adding file '" << InputFilenames[i] + << "': " << error << "\n"; + return 1; + } + + unsigned NumSyms = Module->getSymbolCount(); + for (unsigned I = 0; I < NumSyms; ++I) { + StringRef Name = Module->getSymbolName(I); + if (!DSOSymbolsSet.count(Name)) + continue; + lto_symbol_attributes Attrs = Module->getSymbolAttributes(I); + unsigned Scope = Attrs & LTO_SYMBOL_SCOPE_MASK; + if (Scope != LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN) + KeptDSOSyms.push_back(Name); + } + } + + // Add all the exported symbols to the table of symbols to preserve. + for (unsigned i = 0; i < ExportedSymbols.size(); ++i) + CodeGen.addMustPreserveSymbol(ExportedSymbols[i].c_str()); + + // Add all the dso symbols to the table of symbols to expose. + for (unsigned i = 0; i < KeptDSOSyms.size(); ++i) + CodeGen.addMustPreserveSymbol(KeptDSOSyms[i].c_str()); + + if (!OutputFilename.empty()) { + size_t len = 0; + std::string ErrorInfo; + const void *Code = CodeGen.compile(&len, DisableOpt, DisableInline, + DisableGVNLoadPRE, ErrorInfo); + if (Code == NULL) { + errs() << argv[0] + << ": error compiling the code: " << ErrorInfo << "\n"; + return 1; + } + + raw_fd_ostream FileStream(OutputFilename.c_str(), ErrorInfo, + sys::fs::F_Binary); + if (!ErrorInfo.empty()) { + errs() << argv[0] << ": error opening the file '" << OutputFilename + << "': " << ErrorInfo << "\n"; + return 1; + } + + FileStream.write(reinterpret_cast<const char *>(Code), len); + } else { + std::string ErrorInfo; + const char *OutputName = NULL; + if (!CodeGen.compile_to_file(&OutputName, DisableOpt, DisableInline, + DisableGVNLoadPRE, ErrorInfo)) { + errs() << argv[0] + << ": error compiling the code: " << ErrorInfo + << "\n"; + return 1; + } + + outs() << "Wrote native object file '" << OutputName << "'\n"; + } + + return 0; +} |