1 //===-- llvm-lto: a simple command-line program to link modules with LTO --===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This program takes in a list of bitcode files, links them, performs link-time
11 // optimization, and outputs an object file.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/ADT/StringSet.h"
16 #include "llvm/CodeGen/CommandFlags.h"
17 #include "llvm/LTO/LTOCodeGenerator.h"
18 #include "llvm/LTO/LTOModule.h"
19 #include "llvm/Support/CommandLine.h"
20 #include "llvm/Support/ManagedStatic.h"
21 #include "llvm/Support/PrettyStackTrace.h"
22 #include "llvm/Support/Signals.h"
23 #include "llvm/Support/TargetSelect.h"
24 #include "llvm/Support/raw_ostream.h"
29 DisableOpt("disable-opt", cl::init(false),
30 cl::desc("Do not run any optimization passes"));
33 DisableInline("disable-inlining", cl::init(false),
34 cl::desc("Do not run the inliner pass"));
37 DisableGVNLoadPRE("disable-gvn-loadpre", cl::init(false),
38 cl::desc("Do not run the GVN load PRE pass"));
40 static cl::list<std::string>
41 InputFilenames(cl::Positional, cl::OneOrMore,
42 cl::desc("<input bitcode files>"));
44 static cl::opt<std::string>
45 OutputFilename("o", cl::init(""),
46 cl::desc("Override output filename"),
47 cl::value_desc("filename"));
49 static cl::list<std::string>
50 ExportedSymbols("exported-symbol",
51 cl::desc("Symbol to export from the resulting object file"),
54 static cl::list<std::string>
55 DSOSymbols("dso-symbol",
56 cl::desc("Symbol to put in the symtab in the resulting dso"),
61 std::vector<bool> CanBeHidden;
65 int main(int argc, char **argv) {
66 // Print a stack trace if we signal out.
67 sys::PrintStackTraceOnErrorSignal();
68 PrettyStackTraceProgram X(argc, argv);
70 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
71 cl::ParseCommandLineOptions(argc, argv, "llvm LTO linker\n");
73 // Initialize the configured targets.
74 InitializeAllTargets();
75 InitializeAllTargetMCs();
76 InitializeAllAsmPrinters();
77 InitializeAllAsmParsers();
79 // set up the TargetOptions for the machine
80 TargetOptions Options;
81 Options.LessPreciseFPMADOption = EnableFPMAD;
82 Options.NoFramePointerElim = DisableFPElim;
83 Options.AllowFPOpFusion = FuseFPOps;
84 Options.UnsafeFPMath = EnableUnsafeFPMath;
85 Options.NoInfsFPMath = EnableNoInfsFPMath;
86 Options.NoNaNsFPMath = EnableNoNaNsFPMath;
87 Options.HonorSignDependentRoundingFPMathOption =
88 EnableHonorSignDependentRoundingFPMath;
89 Options.UseSoftFloat = GenerateSoftFloatCalls;
90 if (FloatABIForCalls != FloatABI::Default)
91 Options.FloatABIType = FloatABIForCalls;
92 Options.NoZerosInBSS = DontPlaceZerosInBSS;
93 Options.GuaranteedTailCallOpt = EnableGuaranteedTailCallOpt;
94 Options.DisableTailCalls = DisableTailCalls;
95 Options.StackAlignmentOverride = OverrideStackAlignment;
96 Options.TrapFuncName = TrapFuncName;
97 Options.PositionIndependentExecutable = EnablePIE;
98 Options.EnableSegmentedStacks = SegmentedStacks;
99 Options.UseInitArray = UseInitArray;
101 unsigned BaseArg = 0;
103 LTOCodeGenerator CodeGen;
105 CodeGen.setCodePICModel(LTO_CODEGEN_PIC_MODEL_DYNAMIC);
106 CodeGen.setDebugInfo(LTO_DEBUG_MODEL_DWARF);
107 CodeGen.setTargetOptions(Options);
109 llvm::StringSet<llvm::MallocAllocator> DSOSymbolsSet;
110 for (unsigned i = 0; i < DSOSymbols.size(); ++i)
111 DSOSymbolsSet.insert(DSOSymbols[i]);
113 std::vector<std::string> KeptDSOSyms;
115 for (unsigned i = BaseArg; i < InputFilenames.size(); ++i) {
117 OwningPtr<LTOModule> Module(LTOModule::makeLTOModule(InputFilenames[i].c_str(),
119 if (!error.empty()) {
120 errs() << argv[0] << ": error loading file '" << InputFilenames[i]
121 << "': " << error << "\n";
126 if (!CodeGen.addModule(Module.get(), error)) {
127 errs() << argv[0] << ": error adding file '" << InputFilenames[i]
128 << "': " << error << "\n";
132 unsigned NumSyms = Module->getSymbolCount();
133 for (unsigned I = 0; I < NumSyms; ++I) {
134 StringRef Name = Module->getSymbolName(I);
135 if (!DSOSymbolsSet.count(Name))
137 lto_symbol_attributes Attrs = Module->getSymbolAttributes(I);
138 unsigned Scope = Attrs & LTO_SYMBOL_SCOPE_MASK;
139 if (Scope != LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN)
140 KeptDSOSyms.push_back(Name);
144 // Add all the exported symbols to the table of symbols to preserve.
145 for (unsigned i = 0; i < ExportedSymbols.size(); ++i)
146 CodeGen.addMustPreserveSymbol(ExportedSymbols[i].c_str());
148 // Add all the dso symbols to the table of symbols to expose.
149 for (unsigned i = 0; i < KeptDSOSyms.size(); ++i)
150 CodeGen.addMustPreserveSymbol(KeptDSOSyms[i].c_str());
152 if (!OutputFilename.empty()) {
154 std::string ErrorInfo;
155 const void *Code = CodeGen.compile(&len, DisableOpt, DisableInline,
156 DisableGVNLoadPRE, ErrorInfo);
159 << ": error compiling the code: " << ErrorInfo << "\n";
163 raw_fd_ostream FileStream(OutputFilename.c_str(), ErrorInfo,
165 if (!ErrorInfo.empty()) {
166 errs() << argv[0] << ": error opening the file '" << OutputFilename
167 << "': " << ErrorInfo << "\n";
171 FileStream.write(reinterpret_cast<const char *>(Code), len);
173 std::string ErrorInfo;
174 const char *OutputName = NULL;
175 if (!CodeGen.compile_to_file(&OutputName, DisableOpt, DisableInline,
176 DisableGVNLoadPRE, ErrorInfo)) {
178 << ": error compiling the code: " << ErrorInfo
183 outs() << "Wrote native object file '" << OutputName << "'\n";