1 //===-- llvm-lto2: test harness for the resolution-based LTO interface ----===//
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 and performs
11 // link-time optimization according to the provided symbol resolutions using the
12 // resolution-based LTO interface, and outputs one or more object files.
14 // This program is intended to eventually replace llvm-lto which uses the legacy
17 //===----------------------------------------------------------------------===//
19 #include "llvm/LTO/Caching.h"
20 #include "llvm/CodeGen/CommandFlags.h"
21 #include "llvm/IR/DiagnosticPrinter.h"
22 #include "llvm/LTO/LTO.h"
23 #include "llvm/Support/CommandLine.h"
24 #include "llvm/Support/TargetSelect.h"
25 #include "llvm/Support/Threading.h"
29 using namespace object;
32 OptLevel("O", cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
34 cl::Prefix, cl::ZeroOrMore, cl::init('2'));
36 static cl::opt<char> CGOptLevel(
38 cl::desc("Codegen optimization level (0, 1, 2 or 3, default = '2')"),
41 static cl::list<std::string> InputFilenames(cl::Positional, cl::OneOrMore,
42 cl::desc("<input bitcode files>"));
44 static cl::opt<std::string> OutputFilename("o", cl::Required,
45 cl::desc("Output filename"),
46 cl::value_desc("filename"));
48 static cl::opt<std::string> CacheDir("cache-dir", cl::desc("Cache Directory"),
49 cl::value_desc("directory"));
51 static cl::opt<std::string> OptPipeline("opt-pipeline",
52 cl::desc("Optimizer Pipeline"),
53 cl::value_desc("pipeline"));
55 static cl::opt<std::string> AAPipeline("aa-pipeline",
56 cl::desc("Alias Analysis Pipeline"),
57 cl::value_desc("aapipeline"));
59 static cl::opt<bool> SaveTemps("save-temps", cl::desc("Save temporary files"));
62 ThinLTODistributedIndexes("thinlto-distributed-indexes", cl::init(false),
63 cl::desc("Write out individual index and "
64 "import files for the "
65 "distributed backend case"));
67 static cl::opt<int> Threads("thinlto-threads",
68 cl::init(llvm::heavyweight_hardware_concurrency()));
70 static cl::list<std::string> SymbolResolutions(
72 cl::desc("Specify a symbol resolution: filename,symbolname,resolution\n"
73 "where \"resolution\" is a sequence (which may be empty) of the\n"
74 "following characters:\n"
75 " p - prevailing: the linker has chosen this definition of the\n"
77 " l - local: the definition of this symbol is unpreemptable at\n"
78 " runtime and is known to be in this linkage unit\n"
79 " x - externally visible: the definition of this symbol is\n"
80 " visible outside of the LTO unit\n"
81 "A resolution for each symbol must be specified."),
84 static cl::opt<std::string> OverrideTriple(
86 cl::desc("Replace target triples in input files with this triple"));
88 static cl::opt<std::string> DefaultTriple(
91 "Replace unspecified target triples in input files with this triple"));
93 static void check(Error E, std::string Msg) {
96 handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
97 errs() << "llvm-lto: " << Msg << ": " << EIB.message().c_str() << '\n';
102 template <typename T> static T check(Expected<T> E, std::string Msg) {
104 return std::move(*E);
105 check(E.takeError(), Msg);
109 static void check(std::error_code EC, std::string Msg) {
110 check(errorCodeToError(EC), Msg);
113 template <typename T> static T check(ErrorOr<T> E, std::string Msg) {
115 return std::move(*E);
116 check(E.getError(), Msg);
120 int main(int argc, char **argv) {
121 InitializeAllTargets();
122 InitializeAllTargetMCs();
123 InitializeAllAsmPrinters();
124 InitializeAllAsmParsers();
126 cl::ParseCommandLineOptions(argc, argv, "Resolution-based LTO test harness");
128 // FIXME: Workaround PR30396 which means that a symbol can appear
129 // more than once if it is defined in module-level assembly and
130 // has a GV declaration. We allow (file, symbol) pairs to have multiple
131 // resolutions and apply them in the order observed.
132 std::map<std::pair<std::string, std::string>, std::list<SymbolResolution>>
133 CommandLineResolutions;
134 for (std::string R : SymbolResolutions) {
136 StringRef FileName, SymbolName;
137 std::tie(FileName, Rest) = Rest.split(',');
139 llvm::errs() << "invalid resolution: " << R << '\n';
142 std::tie(SymbolName, Rest) = Rest.split(',');
143 SymbolResolution Res;
144 for (char C : Rest) {
146 Res.Prevailing = true;
148 Res.FinalDefinitionInLinkageUnit = true;
150 Res.VisibleToRegularObj = true;
152 llvm::errs() << "invalid character " << C << " in resolution: " << R
155 CommandLineResolutions[{FileName, SymbolName}].push_back(Res);
158 std::vector<std::unique_ptr<MemoryBuffer>> MBs;
161 Conf.DiagHandler = [](const DiagnosticInfo &DI) {
162 DiagnosticPrinterRawOStream DP(errs());
169 Conf.Options = InitTargetOptionsFromCodeGenFlags();
170 Conf.MAttrs = MAttrs;
171 if (auto RM = getRelocModel())
172 Conf.RelocModel = *RM;
173 Conf.CodeModel = CMModel;
176 check(Conf.addSaveTemps(OutputFilename + "."),
177 "Config::addSaveTemps failed");
179 // Run a custom pipeline, if asked for.
180 Conf.OptPipeline = OptPipeline;
181 Conf.AAPipeline = AAPipeline;
183 Conf.OptLevel = OptLevel - '0';
184 switch (CGOptLevel) {
186 Conf.CGOptLevel = CodeGenOpt::None;
189 Conf.CGOptLevel = CodeGenOpt::Less;
192 Conf.CGOptLevel = CodeGenOpt::Default;
195 Conf.CGOptLevel = CodeGenOpt::Aggressive;
198 llvm::errs() << "invalid cg optimization level: " << CGOptLevel << '\n';
202 Conf.OverrideTriple = OverrideTriple;
203 Conf.DefaultTriple = DefaultTriple;
206 if (ThinLTODistributedIndexes)
207 Backend = createWriteIndexesThinBackend("", "", true, "");
209 Backend = createInProcessThinBackend(Threads);
210 LTO Lto(std::move(Conf), std::move(Backend));
212 bool HasErrors = false;
213 for (std::string F : InputFilenames) {
214 std::unique_ptr<MemoryBuffer> MB = check(MemoryBuffer::getFile(F), F);
215 std::unique_ptr<InputFile> Input =
216 check(InputFile::create(MB->getMemBufferRef()), F);
218 std::vector<SymbolResolution> Res;
219 for (const InputFile::Symbol &Sym : Input->symbols()) {
220 auto I = CommandLineResolutions.find({F, Sym.getName()});
221 if (I == CommandLineResolutions.end()) {
222 llvm::errs() << argv[0] << ": missing symbol resolution for " << F
223 << ',' << Sym.getName() << '\n';
226 Res.push_back(I->second.front());
227 I->second.pop_front();
228 if (I->second.empty())
229 CommandLineResolutions.erase(I);
236 MBs.push_back(std::move(MB));
237 check(Lto.add(std::move(Input), Res), F);
240 if (!CommandLineResolutions.empty()) {
242 for (auto UnusedRes : CommandLineResolutions)
243 llvm::errs() << argv[0] << ": unused symbol resolution for "
244 << UnusedRes.first.first << ',' << UnusedRes.first.second
251 [&](size_t Task) -> std::unique_ptr<lto::NativeObjectStream> {
252 std::string Path = OutputFilename + "." + utostr(Task);
255 auto S = llvm::make_unique<raw_fd_ostream>(Path, EC, sys::fs::F_None);
257 return llvm::make_unique<lto::NativeObjectStream>(std::move(S));
260 auto AddFile = [&](size_t Task, StringRef Path) {
261 auto ReloadedBufferOrErr = MemoryBuffer::getFile(Path);
262 if (auto EC = ReloadedBufferOrErr.getError())
263 report_fatal_error(Twine("Can't reload cached file '") + Path + "': " +
264 EC.message() + "\n");
266 *AddStream(Task)->OS << (*ReloadedBufferOrErr)->getBuffer();
269 NativeObjectCache Cache;
270 if (!CacheDir.empty())
271 Cache = localCache(CacheDir, AddFile);
273 check(Lto.run(AddStream, Cache), "LTO::run failed");