/// claim_file_hook - called by gold to see whether this file is one that
/// our plugin can handle. We'll try to open it and register all the symbols
/// with add_symbol if possible.
static ld_plugin_status claim_file_hook(const ld_plugin_input_file *file,
int *claimed) {
LTOModule *M;
const void *view;
std::unique_ptr<MemoryBuffer> buffer;
if (get_view) {
if (get_view(file->handle, &view) != LDPS_OK) {
(*message)(LDPL_ERROR, "Failed to get a view of %s", file->name);
return LDPS_ERR;
}
} else {
int64_t offset = 0;
// Gold has found what might be IR part-way inside of a file, such as
// an .a archive.
if (file->offset) {
offset = file->offset;
}
if (std::error_code ec = MemoryBuffer::getOpenFileSlice(
file->fd, file->name, buffer, file->filesize, offset)) {
(*message)(LDPL_ERROR, ec.message().c_str());
return LDPS_ERR;
}
view = buffer->getBufferStart();
}
if (!LTOModule::isBitcodeFile(view, file->filesize))
return LDPS_OK;
std::string Error;
M = LTOModule::makeLTOModule(view, file->filesize, TargetOpts, Error);
if (!M) {
(*message)(LDPL_ERROR,
"LLVM gold plugin has failed to create LTO module: %s",
Error.c_str());
return LDPS_OK;
}
*claimed = 1;
Modules.resize(Modules.size() + 1);
claimed_file &cf = Modules.back();
if (!options::triple.empty())
M->setTargetTriple(options::triple.c_str());
cf.handle = file->handle;
unsigned sym_count = M->getSymbolCount();
cf.syms.reserve(sym_count);
for (unsigned i = 0; i != sym_count; ++i) {
lto_symbol_attributes attrs = M->getSymbolAttributes(i);
if ((attrs & LTO_SYMBOL_SCOPE_MASK) == LTO_SYMBOL_SCOPE_INTERNAL)
continue;
cf.syms.push_back(ld_plugin_symbol());
ld_plugin_symbol &sym = cf.syms.back();
sym.name = strdup(M->getSymbolName(i));
sym.version = NULL;
int scope = attrs & LTO_SYMBOL_SCOPE_MASK;
bool CanBeHidden = scope == LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN;
if (!CanBeHidden)
CannotBeHidden.insert(sym.name);
switch (scope) {
case LTO_SYMBOL_SCOPE_HIDDEN:
sym.visibility = LDPV_HIDDEN;
break;
case LTO_SYMBOL_SCOPE_PROTECTED:
sym.visibility = LDPV_PROTECTED;
break;
case 0: // extern
case LTO_SYMBOL_SCOPE_DEFAULT:
case LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN:
sym.visibility = LDPV_DEFAULT;
break;
default:
(*message)(LDPL_ERROR, "Unknown scope attribute: %d", scope);
return LDPS_ERR;
}
int definition = attrs & LTO_SYMBOL_DEFINITION_MASK;
sym.comdat_key = NULL;
switch (definition) {
case LTO_SYMBOL_DEFINITION_REGULAR:
sym.def = LDPK_DEF;
break;
case LTO_SYMBOL_DEFINITION_UNDEFINED:
sym.def = LDPK_UNDEF;
break;
case LTO_SYMBOL_DEFINITION_TENTATIVE:
sym.def = LDPK_COMMON;
break;
case LTO_SYMBOL_DEFINITION_WEAK:
sym.comdat_key = sym.name;
sym.def = LDPK_WEAKDEF;
break;
case LTO_SYMBOL_DEFINITION_WEAKUNDEF:
sym.def = LDPK_WEAKUNDEF;
break;
default:
(*message)(LDPL_ERROR, "Unknown definition attribute: %d", definition);
return LDPS_ERR;
}
sym.size = 0;
sym.resolution = LDPR_UNKNOWN;
}
cf.syms.reserve(cf.syms.size());
if (!cf.syms.empty()) {
if ((*add_symbols)(cf.handle, cf.syms.size(), &cf.syms[0]) != LDPS_OK) {
(*message)(LDPL_ERROR, "Unable to add symbols!");
return LDPS_ERR;
}
}
if (CodeGen) {
std::string Error;
if (!CodeGen->addModule(M, Error)) {
(*message)(LDPL_ERROR, "Error linking module: %s", Error.c_str());
return LDPS_ERR;
}
}
delete M;
return LDPS_OK;
}
int main(int argc, char **argv) {
// Print a stack trace if we signal out.
sys::PrintStackTraceOnErrorSignal();
PrettyStackTraceProgram X(argc, argv);
llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
cl::ParseCommandLineOptions(argc, argv, "llvm LTO linker\n");
if (OptLevel < '0' || OptLevel > '3') {
errs() << argv[0] << ": optimization level must be between 0 and 3\n";
return 1;
}
// Initialize the configured targets.
InitializeAllTargets();
InitializeAllTargetMCs();
InitializeAllAsmPrinters();
InitializeAllAsmParsers();
// set up the TargetOptions for the machine
TargetOptions Options = InitTargetOptionsFromCodeGenFlags();
if (ListSymbolsOnly)
return listSymbols(argv[0], Options);
unsigned BaseArg = 0;
LTOCodeGenerator CodeGen;
if (UseDiagnosticHandler)
CodeGen.setDiagnosticHandler(handleDiagnostics, nullptr);
switch (RelocModel) {
case Reloc::Static:
CodeGen.setCodePICModel(LTO_CODEGEN_PIC_MODEL_STATIC);
break;
case Reloc::PIC_:
CodeGen.setCodePICModel(LTO_CODEGEN_PIC_MODEL_DYNAMIC);
break;
case Reloc::DynamicNoPIC:
CodeGen.setCodePICModel(LTO_CODEGEN_PIC_MODEL_DYNAMIC_NO_PIC);
break;
default:
CodeGen.setCodePICModel(LTO_CODEGEN_PIC_MODEL_DEFAULT);
}
CodeGen.setDebugInfo(LTO_DEBUG_MODEL_DWARF);
CodeGen.setTargetOptions(Options);
llvm::StringSet<llvm::MallocAllocator> DSOSymbolsSet;
for (unsigned i = 0; i < DSOSymbols.size(); ++i)
DSOSymbolsSet.insert(DSOSymbols[i]);
std::vector<std::string> KeptDSOSyms;
for (unsigned i = BaseArg; i < InputFilenames.size(); ++i) {
std::string error;
std::unique_ptr<LTOModule> Module(
LTOModule::createFromFile(InputFilenames[i].c_str(), Options, error));
if (!error.empty()) {
errs() << argv[0] << ": error loading file '" << InputFilenames[i]
<< "': " << error << "\n";
return 1;
}
LTOModule *LTOMod = Module.get();
// We use the first input module as the destination module when
// SetMergedModule is true.
if (SetMergedModule && i == BaseArg) {
// Transfer ownership to the code generator.
CodeGen.setModule(Module.release());
} else if (!CodeGen.addModule(Module.get())) {
// Print a message here so that we know addModule() did not abort.
errs() << argv[0] << ": error adding file '" << InputFilenames[i] << "'\n";
return 1;
}
unsigned NumSyms = LTOMod->getSymbolCount();
for (unsigned I = 0; I < NumSyms; ++I) {
StringRef Name = LTOMod->getSymbolName(I);
if (!DSOSymbolsSet.count(Name))
continue;
lto_symbol_attributes Attrs = LTOMod->getSymbolAttributes(I);
unsigned Scope = Attrs & LTO_SYMBOL_SCOPE_MASK;
if (Scope != LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN)
KeptDSOSyms.push_back(Name);
}
}
// Add all the exported symbols to the table of symbols to preserve.
for (unsigned i = 0; i < ExportedSymbols.size(); ++i)
CodeGen.addMustPreserveSymbol(ExportedSymbols[i].c_str());
// Add all the dso symbols to the table of symbols to expose.
for (unsigned i = 0; i < KeptDSOSyms.size(); ++i)
CodeGen.addMustPreserveSymbol(KeptDSOSyms[i].c_str());
// Set cpu and attrs strings for the default target/subtarget.
CodeGen.setCpu(MCPU.c_str());
CodeGen.setOptLevel(OptLevel - '0');
std::string attrs;
for (unsigned i = 0; i < MAttrs.size(); ++i) {
if (i > 0)
attrs.append(",");
attrs.append(MAttrs[i]);
}
if (!attrs.empty())
CodeGen.setAttr(attrs.c_str());
if (!OutputFilename.empty()) {
std::string ErrorInfo;
std::unique_ptr<MemoryBuffer> Code = CodeGen.compile(
DisableInline, DisableGVNLoadPRE, DisableLTOVectorization, ErrorInfo);
if (!Code) {
errs() << argv[0]
<< ": error compiling the code: " << ErrorInfo << "\n";
return 1;
}
std::error_code EC;
raw_fd_ostream FileStream(OutputFilename, EC, sys::fs::F_None);
if (EC) {
errs() << argv[0] << ": error opening the file '" << OutputFilename
<< "': " << EC.message() << "\n";
return 1;
}
FileStream.write(Code->getBufferStart(), Code->getBufferSize());
} else {
std::string ErrorInfo;
const char *OutputName = nullptr;
if (!CodeGen.compile_to_file(&OutputName, DisableInline,
DisableGVNLoadPRE, DisableLTOVectorization,
ErrorInfo)) {
errs() << argv[0]
<< ": error compiling the code: " << ErrorInfo
<< "\n";
return 1;
}
outs() << "Wrote native object file '" << OutputName << "'\n";
}
return 0;
}