1 //===- llvm-cat.cpp - LLVM module concatenation utility -------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This program is for testing features that rely on multi-module bitcode files.
11 // It takes a list of input modules and uses them to create a multi-module
12 // bitcode file.
13 //
14 //===----------------------------------------------------------------------===//
15
16 #include "llvm/ADT/SmallVector.h"
17 #include "llvm/Bitcode/BitcodeReader.h"
18 #include "llvm/Bitcode/BitcodeWriter.h"
19 #include "llvm/IR/LLVMContext.h"
20 #include "llvm/IR/Module.h"
21 #include "llvm/IRReader/IRReader.h"
22 #include "llvm/Support/CommandLine.h"
23 #include "llvm/Support/Error.h"
24 #include "llvm/Support/FileSystem.h"
25 #include "llvm/Support/MemoryBuffer.h"
26 #include "llvm/Support/SourceMgr.h"
27 #include "llvm/Support/raw_ostream.h"
28 #include <algorithm>
29 #include <memory>
30 #include <string>
31 #include <system_error>
32 #include <vector>
33
34 using namespace llvm;
35
36 static cl::opt<bool>
37 BinaryCat("b", cl::desc("Whether to perform binary concatenation"));
38
39 static cl::opt<std::string> OutputFilename("o", cl::Required,
40 cl::desc("Output filename"),
41 cl::value_desc("filename"));
42
43 static cl::list<std::string> InputFilenames(cl::Positional, cl::ZeroOrMore,
44 cl::desc("<input files>"));
45
main(int argc,char ** argv)46 int main(int argc, char **argv) {
47 cl::ParseCommandLineOptions(argc, argv, "Module concatenation");
48
49 ExitOnError ExitOnErr("llvm-cat: ");
50 LLVMContext Context;
51
52 SmallVector<char, 0> Buffer;
53 BitcodeWriter Writer(Buffer);
54 if (BinaryCat) {
55 for (const auto &InputFilename : InputFilenames) {
56 std::unique_ptr<MemoryBuffer> MB = ExitOnErr(
57 errorOrToExpected(MemoryBuffer::getFileOrSTDIN(InputFilename)));
58 std::vector<BitcodeModule> Mods = ExitOnErr(getBitcodeModuleList(*MB));
59 for (auto &BitcodeMod : Mods) {
60 Buffer.insert(Buffer.end(), BitcodeMod.getBuffer().begin(),
61 BitcodeMod.getBuffer().end());
62 Writer.copyStrtab(BitcodeMod.getStrtab());
63 }
64 }
65 } else {
66 // The string table does not own strings added to it, some of which are
67 // owned by the modules; keep them alive until we write the string table.
68 std::vector<std::unique_ptr<Module>> OwnedMods;
69 for (const auto &InputFilename : InputFilenames) {
70 SMDiagnostic Err;
71 std::unique_ptr<Module> M = parseIRFile(InputFilename, Err, Context);
72 if (!M) {
73 Err.print(argv[0], errs());
74 return 1;
75 }
76 Writer.writeModule(*M);
77 OwnedMods.push_back(std::move(M));
78 }
79 Writer.writeStrtab();
80 }
81
82 std::error_code EC;
83 raw_fd_ostream OS(OutputFilename, EC, sys::fs::OpenFlags::F_None);
84 if (EC) {
85 errs() << argv[0] << ": cannot open " << OutputFilename << " for writing: "
86 << EC.message();
87 return 1;
88 }
89
90 OS.write(Buffer.data(), Buffer.size());
91 return 0;
92 }
93