1 //===- llvm-link.cpp - Low-level LLVM linker ------------------------------===//
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 utility may be invoked in the following manner:
11 // llvm-link a.bc b.bc c.bc -o x.bc
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "llvm/Linker.h"
16 #include "llvm/LLVMContext.h"
17 #include "llvm/Module.h"
18 #include "llvm/Analysis/Verifier.h"
19 #include "llvm/Bitcode/ReaderWriter.h"
20 #include "llvm/Support/CommandLine.h"
21 #include "llvm/Support/ManagedStatic.h"
22 #include "llvm/Support/PrettyStackTrace.h"
23 #include "llvm/Support/ToolOutputFile.h"
24 #include "llvm/Support/SystemUtils.h"
25 #include "llvm/Support/IRReader.h"
26 #include "llvm/Support/Signals.h"
27 #include "llvm/Support/Path.h"
28 #include <memory>
29 using namespace llvm;
30
31 static cl::list<std::string>
32 InputFilenames(cl::Positional, cl::OneOrMore,
33 cl::desc("<input bitcode files>"));
34
35 static cl::opt<std::string>
36 OutputFilename("o", cl::desc("Override output filename"), cl::init("-"),
37 cl::value_desc("filename"));
38
39 static cl::opt<bool>
40 Force("f", cl::desc("Enable binary output on terminals"));
41
42 static cl::opt<bool>
43 OutputAssembly("S",
44 cl::desc("Write output as LLVM assembly"), cl::Hidden);
45
46 static cl::opt<bool>
47 Verbose("v", cl::desc("Print information about actions taken"));
48
49 static cl::opt<bool>
50 DumpAsm("d", cl::desc("Print assembly as linked"), cl::Hidden);
51
52 // LoadFile - Read the specified bitcode file in and return it. This routine
53 // searches the link path for the specified file to try to find it...
54 //
LoadFile(const char * argv0,const std::string & FN,LLVMContext & Context)55 static inline std::auto_ptr<Module> LoadFile(const char *argv0,
56 const std::string &FN,
57 LLVMContext& Context) {
58 sys::Path Filename;
59 if (!Filename.set(FN)) {
60 errs() << "Invalid file name: '" << FN << "'\n";
61 return std::auto_ptr<Module>();
62 }
63
64 SMDiagnostic Err;
65 if (Verbose) errs() << "Loading '" << Filename.c_str() << "'\n";
66 Module* Result = 0;
67
68 const std::string &FNStr = Filename.str();
69 Result = ParseIRFile(FNStr, Err, Context);
70 if (Result) return std::auto_ptr<Module>(Result); // Load successful!
71
72 Err.Print(argv0, errs());
73 return std::auto_ptr<Module>();
74 }
75
main(int argc,char ** argv)76 int main(int argc, char **argv) {
77 // Print a stack trace if we signal out.
78 sys::PrintStackTraceOnErrorSignal();
79 PrettyStackTraceProgram X(argc, argv);
80
81 LLVMContext &Context = getGlobalContext();
82 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
83 cl::ParseCommandLineOptions(argc, argv, "llvm linker\n");
84
85 unsigned BaseArg = 0;
86 std::string ErrorMessage;
87
88 std::auto_ptr<Module> Composite(LoadFile(argv[0],
89 InputFilenames[BaseArg], Context));
90 if (Composite.get() == 0) {
91 errs() << argv[0] << ": error loading file '"
92 << InputFilenames[BaseArg] << "'\n";
93 return 1;
94 }
95
96 for (unsigned i = BaseArg+1; i < InputFilenames.size(); ++i) {
97 std::auto_ptr<Module> M(LoadFile(argv[0],
98 InputFilenames[i], Context));
99 if (M.get() == 0) {
100 errs() << argv[0] << ": error loading file '" <<InputFilenames[i]<< "'\n";
101 return 1;
102 }
103
104 if (Verbose) errs() << "Linking in '" << InputFilenames[i] << "'\n";
105
106 if (Linker::LinkModules(Composite.get(), M.get(), Linker::DestroySource,
107 &ErrorMessage)) {
108 errs() << argv[0] << ": link error in '" << InputFilenames[i]
109 << "': " << ErrorMessage << "\n";
110 return 1;
111 }
112 }
113
114 // TODO: Iterate over the -l list and link in any modules containing
115 // global symbols that have not been resolved so far.
116
117 if (DumpAsm) errs() << "Here's the assembly:\n" << *Composite;
118
119 std::string ErrorInfo;
120 tool_output_file Out(OutputFilename.c_str(), ErrorInfo,
121 raw_fd_ostream::F_Binary);
122 if (!ErrorInfo.empty()) {
123 errs() << ErrorInfo << '\n';
124 return 1;
125 }
126
127 if (verifyModule(*Composite)) {
128 errs() << argv[0] << ": linked module is broken!\n";
129 return 1;
130 }
131
132 if (Verbose) errs() << "Writing bitcode...\n";
133 if (OutputAssembly) {
134 Out.os() << *Composite;
135 } else if (Force || !CheckBitcodeOutputToConsole(Out.os(), true))
136 WriteBitcodeToFile(Composite.get(), Out.os());
137
138 // Declare success.
139 Out.keep();
140
141 return 0;
142 }
143