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 cl::opt<std::string>
94 OptRemarksOutput("pass-remarks-output",
95 cl::desc("YAML output file for optimization remarks"));
97 static cl::opt<bool> OptRemarksWithHotness(
98 "pass-remarks-with-hotness",
99 cl::desc("Whether to include hotness informations in the remarks.\n"
100 "Has effect only if -pass-remarks-output is specified."));
102 static void check(Error E, std::string Msg) {
105 handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
106 errs() << "llvm-lto2: " << Msg << ": " << EIB.message().c_str() << '\n';
111 template <typename T> static T check(Expected<T> E, std::string Msg) {
113 return std::move(*E);
114 check(E.takeError(), Msg);
118 static void check(std::error_code EC, std::string Msg) {
119 check(errorCodeToError(EC), Msg);
122 template <typename T> static T check(ErrorOr<T> E, std::string Msg) {
124 return std::move(*E);
125 check(E.getError(), Msg);
129 int main(int argc, char **argv) {
130 InitializeAllTargets();
131 InitializeAllTargetMCs();
132 InitializeAllAsmPrinters();
133 InitializeAllAsmParsers();
135 cl::ParseCommandLineOptions(argc, argv, "Resolution-based LTO test harness");
137 // FIXME: Workaround PR30396 which means that a symbol can appear
138 // more than once if it is defined in module-level assembly and
139 // has a GV declaration. We allow (file, symbol) pairs to have multiple
140 // resolutions and apply them in the order observed.
141 std::map<std::pair<std::string, std::string>, std::list<SymbolResolution>>
142 CommandLineResolutions;
143 for (std::string R : SymbolResolutions) {
145 StringRef FileName, SymbolName;
146 std::tie(FileName, Rest) = Rest.split(',');
148 llvm::errs() << "invalid resolution: " << R << '\n';
151 std::tie(SymbolName, Rest) = Rest.split(',');
152 SymbolResolution Res;
153 for (char C : Rest) {
155 Res.Prevailing = true;
157 Res.FinalDefinitionInLinkageUnit = true;
159 Res.VisibleToRegularObj = true;
161 llvm::errs() << "invalid character " << C << " in resolution: " << R
164 CommandLineResolutions[{FileName, SymbolName}].push_back(Res);
167 std::vector<std::unique_ptr<MemoryBuffer>> MBs;
170 Conf.DiagHandler = [](const DiagnosticInfo &DI) {
171 DiagnosticPrinterRawOStream DP(errs());
178 Conf.Options = InitTargetOptionsFromCodeGenFlags();
179 Conf.MAttrs = MAttrs;
180 if (auto RM = getRelocModel())
181 Conf.RelocModel = *RM;
182 Conf.CodeModel = CMModel;
185 check(Conf.addSaveTemps(OutputFilename + "."),
186 "Config::addSaveTemps failed");
188 // Optimization remarks.
189 Conf.RemarksFilename = OptRemarksOutput;
190 Conf.RemarksWithHotness = OptRemarksWithHotness;
192 // Run a custom pipeline, if asked for.
193 Conf.OptPipeline = OptPipeline;
194 Conf.AAPipeline = AAPipeline;
196 Conf.OptLevel = OptLevel - '0';
197 switch (CGOptLevel) {
199 Conf.CGOptLevel = CodeGenOpt::None;
202 Conf.CGOptLevel = CodeGenOpt::Less;
205 Conf.CGOptLevel = CodeGenOpt::Default;
208 Conf.CGOptLevel = CodeGenOpt::Aggressive;
211 llvm::errs() << "invalid cg optimization level: " << CGOptLevel << '\n';
215 if (FileType.getNumOccurrences())
216 Conf.CGFileType = FileType;
218 Conf.OverrideTriple = OverrideTriple;
219 Conf.DefaultTriple = DefaultTriple;
222 if (ThinLTODistributedIndexes)
223 Backend = createWriteIndexesThinBackend("", "", true, "");
225 Backend = createInProcessThinBackend(Threads);
226 LTO Lto(std::move(Conf), std::move(Backend));
228 bool HasErrors = false;
229 for (std::string F : InputFilenames) {
230 std::unique_ptr<MemoryBuffer> MB = check(MemoryBuffer::getFile(F), F);
231 std::unique_ptr<InputFile> Input =
232 check(InputFile::create(MB->getMemBufferRef()), F);
234 std::vector<SymbolResolution> Res;
235 for (const InputFile::Symbol &Sym : Input->symbols()) {
236 auto I = CommandLineResolutions.find({F, Sym.getName()});
237 if (I == CommandLineResolutions.end()) {
238 llvm::errs() << argv[0] << ": missing symbol resolution for " << F
239 << ',' << Sym.getName() << '\n';
242 Res.push_back(I->second.front());
243 I->second.pop_front();
244 if (I->second.empty())
245 CommandLineResolutions.erase(I);
252 MBs.push_back(std::move(MB));
253 check(Lto.add(std::move(Input), Res), F);
256 if (!CommandLineResolutions.empty()) {
258 for (auto UnusedRes : CommandLineResolutions)
259 llvm::errs() << argv[0] << ": unused symbol resolution for "
260 << UnusedRes.first.first << ',' << UnusedRes.first.second
267 [&](size_t Task) -> std::unique_ptr<lto::NativeObjectStream> {
268 std::string Path = OutputFilename + "." + utostr(Task);
271 auto S = llvm::make_unique<raw_fd_ostream>(Path, EC, sys::fs::F_None);
273 return llvm::make_unique<lto::NativeObjectStream>(std::move(S));
276 auto AddFile = [&](size_t Task, StringRef Path) {
277 auto ReloadedBufferOrErr = MemoryBuffer::getFile(Path);
278 if (auto EC = ReloadedBufferOrErr.getError())
279 report_fatal_error(Twine("Can't reload cached file '") + Path + "': " +
280 EC.message() + "\n");
282 *AddStream(Task)->OS << (*ReloadedBufferOrErr)->getBuffer();
285 NativeObjectCache Cache;
286 if (!CacheDir.empty())
287 Cache = localCache(CacheDir, AddFile);
289 check(Lto.run(AddStream, Cache), "LTO::run failed");