1 //===-- llvm-modextract.cpp - LLVM module extractor utility ---------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This program is for testing features that rely on multi-module bitcode files. 10 // It takes a multi-module bitcode file, extracts one of the modules and writes 11 // it to the output file. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "llvm/Bitcode/BitcodeReader.h" 16 #include "llvm/Bitcode/BitcodeWriter.h" 17 #include "llvm/Support/CommandLine.h" 18 #include "llvm/Support/Error.h" 19 #include "llvm/Support/FileSystem.h" 20 #include "llvm/Support/ToolOutputFile.h" 21 22 using namespace llvm; 23 24 static cl::OptionCategory ModextractCategory("Modextract Options"); 25 26 static cl::opt<bool> 27 BinaryExtract("b", cl::desc("Whether to perform binary extraction"), 28 cl::cat(ModextractCategory)); 29 30 static cl::opt<std::string> OutputFilename("o", cl::Required, 31 cl::desc("Output filename"), 32 cl::value_desc("filename"), 33 cl::cat(ModextractCategory)); 34 35 static cl::opt<std::string> InputFilename(cl::Positional, 36 cl::desc("<input bitcode>"), 37 cl::init("-"), 38 cl::cat(ModextractCategory)); 39 40 static cl::opt<unsigned> ModuleIndex("n", cl::Required, 41 cl::desc("Index of module to extract"), 42 cl::value_desc("index"), 43 cl::cat(ModextractCategory)); 44 45 int main(int argc, char **argv) { 46 cl::HideUnrelatedOptions({&ModextractCategory, &getColorCategory()}); 47 cl::ParseCommandLineOptions(argc, argv, "Module extractor"); 48 49 ExitOnError ExitOnErr("llvm-modextract: error: "); 50 51 std::unique_ptr<MemoryBuffer> MB = 52 ExitOnErr(errorOrToExpected(MemoryBuffer::getFileOrSTDIN(InputFilename))); 53 std::vector<BitcodeModule> Ms = ExitOnErr(getBitcodeModuleList(*MB)); 54 55 LLVMContext Context; 56 if (ModuleIndex >= Ms.size()) { 57 errs() << "llvm-modextract: error: module index out of range; bitcode file " 58 "contains " 59 << Ms.size() << " module(s)\n"; 60 return 1; 61 } 62 63 std::error_code EC; 64 std::unique_ptr<ToolOutputFile> Out( 65 new ToolOutputFile(OutputFilename, EC, sys::fs::OF_None)); 66 ExitOnErr(errorCodeToError(EC)); 67 68 if (BinaryExtract) { 69 SmallVector<char, 0> Result; 70 BitcodeWriter Writer(Result); 71 Result.append(Ms[ModuleIndex].getBuffer().begin(), 72 Ms[ModuleIndex].getBuffer().end()); 73 Writer.copyStrtab(Ms[ModuleIndex].getStrtab()); 74 Out->os() << Result; 75 Out->keep(); 76 return 0; 77 } 78 79 std::unique_ptr<Module> M = ExitOnErr(Ms[ModuleIndex].parseModule(Context)); 80 WriteBitcodeToFile(*M, Out->os()); 81 82 Out->keep(); 83 return 0; 84 } 85