//===----------------------------------------------------------------------===//
#include "llvm/Config/config.h" // plugin-api.h requires HAVE_STDINT_H
-#include "llvm-c/lto.h"
+#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/StringSet.h"
+#include "llvm/Analysis/TargetLibraryInfo.h"
+#include "llvm/Analysis/TargetTransformInfo.h"
+#include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/CodeGen/Analysis.h"
#include "llvm/CodeGen/CommandFlags.h"
-#include "llvm/LTO/LTOCodeGenerator.h"
-#include "llvm/LTO/LTOModule.h"
-#include "llvm/Support/Errno.h"
-#include "llvm/Support/FileSystem.h"
+#include "llvm/CodeGen/ParallelCG.h"
+#include "llvm/IR/AutoUpgrade.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DiagnosticInfo.h"
+#include "llvm/IR/DiagnosticPrinter.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/LegacyPassManager.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/Verifier.h"
+#include "llvm/Linker/Linker.h"
+#include "llvm/MC/SubtargetFeature.h"
+#include "llvm/Object/IRObjectFile.h"
+#include "llvm/Object/FunctionIndexObjectFile.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/Host.h"
+#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/MemoryBuffer.h"
-#include "llvm/Support/Path.h"
-#include "llvm/Support/Program.h"
+#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/TargetSelect.h"
-#include "llvm/Support/ToolOutputFile.h"
-#include <cerrno>
-#include <cstdlib>
-#include <cstring>
-#include <fstream>
+#include "llvm/Transforms/IPO.h"
+#include "llvm/Transforms/IPO/PassManagerBuilder.h"
+#include "llvm/Transforms/Utils/GlobalStatus.h"
+#include "llvm/Transforms/Utils/ModuleUtils.h"
+#include "llvm/Transforms/Utils/ValueMapper.h"
#include <list>
#include <plugin-api.h>
#include <system_error>
#include <vector>
-// Support Windows/MinGW crazyness.
-#ifdef _WIN32
-# include <io.h>
-# define lseek _lseek
-# define read _read
-#endif
-
#ifndef LDPO_PIE
// FIXME: remove this declaration when we stop maintaining Ubuntu Quantal and
// Precise and Debian Wheezy (binutils 2.23 is required)
abort();
}
-static ld_plugin_add_symbols add_symbols = NULL;
-static ld_plugin_get_symbols get_symbols = NULL;
-static ld_plugin_add_input_file add_input_file = NULL;
-static ld_plugin_set_extra_library_path set_extra_library_path = NULL;
-static ld_plugin_get_view get_view = NULL;
+static ld_plugin_get_input_file get_input_file = nullptr;
+static ld_plugin_release_input_file release_input_file = nullptr;
+static ld_plugin_add_symbols add_symbols = nullptr;
+static ld_plugin_get_symbols get_symbols = nullptr;
+static ld_plugin_add_input_file add_input_file = nullptr;
+static ld_plugin_set_extra_library_path set_extra_library_path = nullptr;
+static ld_plugin_get_view get_view = nullptr;
static ld_plugin_message message = discard_message;
-static lto_codegen_model output_type = LTO_CODEGEN_PIC_MODEL_STATIC;
+static Reloc::Model RelocationModel = Reloc::Default;
static std::string output_name = "";
static std::list<claimed_file> Modules;
static std::vector<std::string> Cleanup;
-static LTOCodeGenerator *CodeGen = nullptr;
-static StringSet<> CannotBeHidden;
static llvm::TargetOptions TargetOpts;
namespace options {
- enum generate_bc { BC_NO, BC_ALSO, BC_ONLY };
+ enum OutputType {
+ OT_NORMAL,
+ OT_DISABLE,
+ OT_BC_ONLY,
+ OT_SAVE_TEMPS
+ };
static bool generate_api_file = false;
- static generate_bc generate_bc_file = BC_NO;
- static std::string bc_path;
+ static OutputType TheOutputType = OT_NORMAL;
+ static unsigned OptLevel = 2;
+ static unsigned Parallelism = 1;
+#ifdef NDEBUG
+ static bool DisableVerify = true;
+#else
+ static bool DisableVerify = false;
+#endif
static std::string obj_path;
static std::string extra_library_path;
static std::string triple;
static std::string mcpu;
+ // When the thinlto plugin option is specified, only read the function
+ // the information from intermediate files and write a combined
+ // global index for the ThinLTO backends.
+ static bool thinlto = false;
// Additional options to pass into the code generator.
// Note: This array will contain all plugin options which are not claimed
// as plugin exclusive to pass to the code generator.
// For example, "generate-api-file" and "as"options are for the plugin
// use only and will not be passed.
- static std::vector<std::string> extra;
+ static std::vector<const char *> extra;
- static void process_plugin_option(const char* opt_)
+ static void process_plugin_option(const char *opt_)
{
- if (opt_ == NULL)
+ if (opt_ == nullptr)
return;
llvm::StringRef opt = opt_;
} else if (opt.startswith("obj-path=")) {
obj_path = opt.substr(strlen("obj-path="));
} else if (opt == "emit-llvm") {
- generate_bc_file = BC_ONLY;
- } else if (opt == "also-emit-llvm") {
- generate_bc_file = BC_ALSO;
- } else if (opt.startswith("also-emit-llvm=")) {
- llvm::StringRef path = opt.substr(strlen("also-emit-llvm="));
- generate_bc_file = BC_ALSO;
- if (!bc_path.empty()) {
- (*message)(LDPL_WARNING, "Path to the output IL file specified twice. "
- "Discarding %s", opt_);
- } else {
- bc_path = path;
- }
+ TheOutputType = OT_BC_ONLY;
+ } else if (opt == "save-temps") {
+ TheOutputType = OT_SAVE_TEMPS;
+ } else if (opt == "disable-output") {
+ TheOutputType = OT_DISABLE;
+ } else if (opt == "thinlto") {
+ thinlto = true;
+ } else if (opt.size() == 2 && opt[0] == 'O') {
+ if (opt[1] < '0' || opt[1] > '3')
+ message(LDPL_FATAL, "Optimization level must be between 0 and 3");
+ OptLevel = opt[1] - '0';
+ } else if (opt.startswith("jobs=")) {
+ if (StringRef(opt_ + 5).getAsInteger(10, Parallelism))
+ message(LDPL_FATAL, "Invalid parallelism level: %s", opt_ + 5);
+ } else if (opt == "disable-verify") {
+ DisableVerify = true;
} else {
// Save this option to pass to the code generator.
- extra.push_back(opt);
+ // ParseCommandLineOptions() expects argv[0] to be program name. Lazily
+ // add that.
+ if (extra.empty())
+ extra.push_back("LLVMgold");
+
+ extra.push_back(opt_);
}
}
}
case LDPO_REL: // .o
case LDPO_DYN: // .so
case LDPO_PIE: // position independent executable
- output_type = LTO_CODEGEN_PIC_MODEL_DYNAMIC;
+ RelocationModel = Reloc::PIC_;
break;
case LDPO_EXEC: // .exe
- output_type = LTO_CODEGEN_PIC_MODEL_STATIC;
+ RelocationModel = Reloc::Static;
break;
default:
- (*message)(LDPL_ERROR, "Unknown output file type %d",
- tv->tv_u.tv_val);
+ message(LDPL_ERROR, "Unknown output file type %d", tv->tv_u.tv_val);
return LDPS_ERR;
}
break;
ld_plugin_register_claim_file callback;
callback = tv->tv_u.tv_register_claim_file;
- if ((*callback)(claim_file_hook) != LDPS_OK)
+ if (callback(claim_file_hook) != LDPS_OK)
return LDPS_ERR;
registeredClaimFile = true;
ld_plugin_register_all_symbols_read callback;
callback = tv->tv_u.tv_register_all_symbols_read;
- if ((*callback)(all_symbols_read_hook) != LDPS_OK)
+ if (callback(all_symbols_read_hook) != LDPS_OK)
return LDPS_ERR;
RegisteredAllSymbolsRead = true;
ld_plugin_register_cleanup callback;
callback = tv->tv_u.tv_register_cleanup;
- if ((*callback)(cleanup_hook) != LDPS_OK)
+ if (callback(cleanup_hook) != LDPS_OK)
return LDPS_ERR;
} break;
+ case LDPT_GET_INPUT_FILE:
+ get_input_file = tv->tv_u.tv_get_input_file;
+ break;
+ case LDPT_RELEASE_INPUT_FILE:
+ release_input_file = tv->tv_u.tv_release_input_file;
+ break;
case LDPT_ADD_SYMBOLS:
add_symbols = tv->tv_u.tv_add_symbols;
break;
}
if (!registeredClaimFile) {
- (*message)(LDPL_ERROR, "register_claim_file not passed to LLVMgold.");
+ message(LDPL_ERROR, "register_claim_file not passed to LLVMgold.");
return LDPS_ERR;
}
if (!add_symbols) {
- (*message)(LDPL_ERROR, "add_symbols not passed to LLVMgold.");
+ message(LDPL_ERROR, "add_symbols not passed to LLVMgold.");
return LDPS_ERR;
}
if (!RegisteredAllSymbolsRead)
return LDPS_OK;
- CodeGen = new LTOCodeGenerator();
-
- // Pass through extra options to the code generator.
- if (!options::extra.empty()) {
- for (std::vector<std::string>::iterator it = options::extra.begin();
- it != options::extra.end(); ++it) {
- CodeGen->setCodeGenDebugOptions((*it).c_str());
- }
+ if (!get_input_file) {
+ message(LDPL_ERROR, "get_input_file not passed to LLVMgold.");
+ return LDPS_ERR;
+ }
+ if (!release_input_file) {
+ message(LDPL_ERROR, "relesase_input_file not passed to LLVMgold.");
+ return LDPS_ERR;
}
- CodeGen->parseCodeGenDebugOptions();
- if (MAttrs.size()) {
- std::string Attrs;
- for (unsigned I = 0; I < MAttrs.size(); ++I) {
- if (I > 0)
- Attrs.append(",");
- Attrs.append(MAttrs[I]);
- }
- CodeGen->setAttr(Attrs.c_str());
+ return LDPS_OK;
+}
+
+static const GlobalObject *getBaseObject(const GlobalValue &GV) {
+ if (auto *GA = dyn_cast<GlobalAlias>(&GV))
+ return GA->getBaseObject();
+ return cast<GlobalObject>(&GV);
+}
+
+static bool shouldSkip(uint32_t Symflags) {
+ if (!(Symflags & object::BasicSymbolRef::SF_Global))
+ return true;
+ if (Symflags & object::BasicSymbolRef::SF_FormatSpecific)
+ return true;
+ return false;
+}
+
+static void diagnosticHandler(const DiagnosticInfo &DI) {
+ if (const auto *BDI = dyn_cast<BitcodeDiagnosticInfo>(&DI)) {
+ std::error_code EC = BDI->getError();
+ if (EC == BitcodeError::InvalidBitcodeSignature)
+ return;
}
- TargetOpts = InitTargetOptionsFromCodeGenFlags();
- CodeGen->setTargetOptions(TargetOpts);
+ std::string ErrStorage;
+ {
+ raw_string_ostream OS(ErrStorage);
+ DiagnosticPrinterRawOStream DP(OS);
+ DI.print(DP);
+ }
+ ld_plugin_level Level;
+ switch (DI.getSeverity()) {
+ case DS_Error:
+ message(LDPL_FATAL, "LLVM gold plugin has failed to create LTO module: %s",
+ ErrStorage.c_str());
+ llvm_unreachable("Fatal doesn't return.");
+ case DS_Warning:
+ Level = LDPL_WARNING;
+ break;
+ case DS_Note:
+ case DS_Remark:
+ Level = LDPL_INFO;
+ break;
+ }
+ message(Level, "LLVM gold plugin: %s", ErrStorage.c_str());
+}
- return LDPS_OK;
+static void diagnosticHandlerForContext(const DiagnosticInfo &DI,
+ void *Context) {
+ diagnosticHandler(DI);
}
/// Called by gold to see whether this file is one that our plugin can handle.
/// possible.
static ld_plugin_status claim_file_hook(const ld_plugin_input_file *file,
int *claimed) {
- const void *view;
- std::unique_ptr<MemoryBuffer> buffer;
+ LLVMContext Context;
+ MemoryBufferRef BufferRef;
+ std::unique_ptr<MemoryBuffer> Buffer;
if (get_view) {
+ const void *view;
if (get_view(file->handle, &view) != LDPS_OK) {
- (*message)(LDPL_ERROR, "Failed to get a view of %s", file->name);
+ message(LDPL_ERROR, "Failed to get a view of %s", file->name);
return LDPS_ERR;
}
+ BufferRef =
+ MemoryBufferRef(StringRef((const char *)view, file->filesize), "");
} else {
int64_t offset = 0;
// Gold has found what might be IR part-way inside of a file, such as
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());
+ ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
+ MemoryBuffer::getOpenFileSlice(file->fd, file->name, file->filesize,
+ offset);
+ if (std::error_code EC = BufferOrErr.getError()) {
+ message(LDPL_ERROR, EC.message().c_str());
return LDPS_ERR;
}
- view = buffer->getBufferStart();
+ Buffer = std::move(BufferOrErr.get());
+ BufferRef = Buffer->getMemBufferRef();
}
- if (!LTOModule::isBitcodeFile(view, file->filesize))
+ Context.setDiagnosticHandler(diagnosticHandlerForContext);
+ ErrorOr<std::unique_ptr<object::IRObjectFile>> ObjOrErr =
+ object::IRObjectFile::create(BufferRef, Context);
+ std::error_code EC = ObjOrErr.getError();
+ if (EC == object::object_error::invalid_file_type ||
+ EC == object::object_error::bitcode_section_not_found)
return LDPS_OK;
- std::string Error;
- LTOModule *M =
- LTOModule::createFromBuffer(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;
+
+ if (EC) {
+ message(LDPL_ERROR, "LLVM gold plugin has failed to create LTO module: %s",
+ EC.message().c_str());
+ return LDPS_ERR;
}
+ std::unique_ptr<object::IRObjectFile> Obj = std::move(*ObjOrErr);
- *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)
+ // If we are doing ThinLTO compilation, don't need to process the symbols.
+ // Later we simply build a combined index file after all files are claimed.
+ if (options::thinlto)
+ return LDPS_OK;
+
+ for (auto &Sym : Obj->symbols()) {
+ uint32_t Symflags = Sym.getFlags();
+ if (shouldSkip(Symflags))
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.version = nullptr;
+
+ SmallString<64> Name;
+ {
+ raw_svector_ostream OS(Name);
+ Sym.printName(OS);
+ }
+ sym.name = strdup(Name.c_str());
+
+ const GlobalValue *GV = Obj->getSymbolGV(Sym.getRawDataRefImpl());
+
+ sym.visibility = LDPV_DEFAULT;
+ if (GV) {
+ switch (GV->getVisibility()) {
+ case GlobalValue::DefaultVisibility:
+ sym.visibility = LDPV_DEFAULT;
+ break;
+ case GlobalValue::HiddenVisibility:
sym.visibility = LDPV_HIDDEN;
break;
- case LTO_SYMBOL_SCOPE_PROTECTED:
+ case GlobalValue::ProtectedVisibility:
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:
+ if (Symflags & object::BasicSymbolRef::SF_Undefined) {
+ sym.def = LDPK_UNDEF;
+ if (GV && GV->hasExternalWeakLinkage())
sym.def = LDPK_WEAKUNDEF;
- break;
- default:
- (*message)(LDPL_ERROR, "Unknown definition attribute: %d", definition);
- return LDPS_ERR;
+ } else {
+ sym.def = LDPK_DEF;
+ if (GV) {
+ assert(!GV->hasExternalWeakLinkage() &&
+ !GV->hasAvailableExternallyLinkage() && "Not a declaration!");
+ if (GV->hasCommonLinkage())
+ sym.def = LDPK_COMMON;
+ else if (GV->isWeakForLinker())
+ sym.def = LDPK_WEAKDEF;
+ }
}
sym.size = 0;
+ sym.comdat_key = nullptr;
+ if (GV) {
+ const GlobalObject *Base = getBaseObject(*GV);
+ if (!Base)
+ message(LDPL_FATAL, "Unable to determine comdat of alias!");
+ const Comdat *C = Base->getComdat();
+ if (C)
+ sym.comdat_key = strdup(C->getName().str().c_str());
+ else if (Base->hasWeakLinkage() || Base->hasLinkOnceLinkage())
+ sym.comdat_key = strdup(sym.name);
+ }
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!");
+ if (add_symbols(cf.handle, cf.syms.size(), cf.syms.data()) != 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;
- }
+ return LDPS_OK;
+}
+
+static void keepGlobalValue(GlobalValue &GV,
+ std::vector<GlobalAlias *> &KeptAliases) {
+ assert(!GV.hasLocalLinkage());
+
+ if (auto *GA = dyn_cast<GlobalAlias>(&GV))
+ KeptAliases.push_back(GA);
+
+ switch (GV.getLinkage()) {
+ default:
+ break;
+ case GlobalValue::LinkOnceAnyLinkage:
+ GV.setLinkage(GlobalValue::WeakAnyLinkage);
+ break;
+ case GlobalValue::LinkOnceODRLinkage:
+ GV.setLinkage(GlobalValue::WeakODRLinkage);
+ break;
}
- delete M;
+ assert(!GV.isDiscardableIfUnused());
+}
- return LDPS_OK;
+static void internalize(GlobalValue &GV) {
+ if (GV.isDeclarationForLinker())
+ return; // We get here if there is a matching asm definition.
+ if (!GV.hasLocalLinkage())
+ GV.setLinkage(GlobalValue::InternalLinkage);
}
-static bool mustPreserve(const claimed_file &F, int i) {
- if (F.syms[i].resolution == LDPR_PREVAILING_DEF)
- return true;
- if (F.syms[i].resolution == LDPR_PREVAILING_DEF_IRONLY_EXP)
- return CannotBeHidden.count(F.syms[i].name);
- return false;
+static void drop(GlobalValue &GV) {
+ if (auto *F = dyn_cast<Function>(&GV)) {
+ F->deleteBody();
+ F->setComdat(nullptr); // Should deleteBody do this?
+ return;
+ }
+
+ if (auto *Var = dyn_cast<GlobalVariable>(&GV)) {
+ Var->setInitializer(nullptr);
+ Var->setLinkage(
+ GlobalValue::ExternalLinkage); // Should setInitializer do this?
+ Var->setComdat(nullptr); // and this?
+ return;
+ }
+
+ auto &Alias = cast<GlobalAlias>(GV);
+ Module &M = *Alias.getParent();
+ PointerType &Ty = *cast<PointerType>(Alias.getType());
+ GlobalValue::LinkageTypes L = Alias.getLinkage();
+ auto *Var =
+ new GlobalVariable(M, Ty.getElementType(), /*isConstant*/ false, L,
+ /*Initializer*/ nullptr);
+ Var->takeName(&Alias);
+ Alias.replaceAllUsesWith(Var);
+ Alias.eraseFromParent();
}
-/// all_symbols_read_hook - gold informs us that all symbols have been read.
-/// At this point, we use get_symbols to see if any of our definitions have
-/// been overridden by a native object file. Then, perform optimization and
-/// codegen.
-static ld_plugin_status all_symbols_read_hook(void) {
- std::ofstream api_file;
- assert(CodeGen);
-
- if (options::generate_api_file) {
- api_file.open("apifile.txt", std::ofstream::out | std::ofstream::trunc);
- if (!api_file.is_open()) {
- (*message)(LDPL_FATAL, "Unable to open apifile.txt for writing.");
- abort();
- }
+static const char *getResolutionName(ld_plugin_symbol_resolution R) {
+ switch (R) {
+ case LDPR_UNKNOWN:
+ return "UNKNOWN";
+ case LDPR_UNDEF:
+ return "UNDEF";
+ case LDPR_PREVAILING_DEF:
+ return "PREVAILING_DEF";
+ case LDPR_PREVAILING_DEF_IRONLY:
+ return "PREVAILING_DEF_IRONLY";
+ case LDPR_PREEMPTED_REG:
+ return "PREEMPTED_REG";
+ case LDPR_PREEMPTED_IR:
+ return "PREEMPTED_IR";
+ case LDPR_RESOLVED_IR:
+ return "RESOLVED_IR";
+ case LDPR_RESOLVED_EXEC:
+ return "RESOLVED_EXEC";
+ case LDPR_RESOLVED_DYN:
+ return "RESOLVED_DYN";
+ case LDPR_PREVAILING_DEF_IRONLY_EXP:
+ return "PREVAILING_DEF_IRONLY_EXP";
+ }
+ llvm_unreachable("Unknown resolution");
+}
+
+namespace {
+class LocalValueMaterializer final : public ValueMaterializer {
+ DenseSet<GlobalValue *> &Dropped;
+ DenseMap<GlobalObject *, GlobalObject *> LocalVersions;
+
+public:
+ LocalValueMaterializer(DenseSet<GlobalValue *> &Dropped) : Dropped(Dropped) {}
+ Value *materializeValueFor(Value *V) override;
+};
+}
+
+Value *LocalValueMaterializer::materializeValueFor(Value *V) {
+ auto *GO = dyn_cast<GlobalObject>(V);
+ if (!GO)
+ return nullptr;
+
+ auto I = LocalVersions.find(GO);
+ if (I != LocalVersions.end())
+ return I->second;
+
+ if (!Dropped.count(GO))
+ return nullptr;
+
+ Module &M = *GO->getParent();
+ GlobalValue::LinkageTypes L = GO->getLinkage();
+ GlobalObject *Declaration;
+ if (auto *F = dyn_cast<Function>(GO)) {
+ Declaration = Function::Create(F->getFunctionType(), L, "", &M);
+ } else {
+ auto *Var = cast<GlobalVariable>(GO);
+ Declaration = new GlobalVariable(M, Var->getType()->getElementType(),
+ Var->isConstant(), L,
+ /*Initializer*/ nullptr);
}
+ Declaration->takeName(GO);
+ Declaration->copyAttributesFrom(GO);
+
+ GO->setLinkage(GlobalValue::InternalLinkage);
+ GO->setName(Declaration->getName());
+ Dropped.erase(GO);
+ GO->replaceAllUsesWith(Declaration);
+
+ LocalVersions[Declaration] = GO;
+
+ return GO;
+}
+
+static Constant *mapConstantToLocalCopy(Constant *C, ValueToValueMapTy &VM,
+ LocalValueMaterializer *Materializer) {
+ return MapValue(C, VM, RF_IgnoreMissingEntries, nullptr, Materializer);
+}
+
+static void freeSymName(ld_plugin_symbol &Sym) {
+ free(Sym.name);
+ free(Sym.comdat_key);
+ Sym.name = nullptr;
+ Sym.comdat_key = nullptr;
+}
+
+static std::unique_ptr<FunctionInfoIndex>
+getFunctionIndexForFile(claimed_file &F, ld_plugin_input_file &Info) {
+
+ if (get_symbols(F.handle, F.syms.size(), &F.syms[0]) != LDPS_OK)
+ message(LDPL_FATAL, "Failed to get symbol information");
+
+ const void *View;
+ if (get_view(F.handle, &View) != LDPS_OK)
+ message(LDPL_FATAL, "Failed to get a view of file");
- for (std::list<claimed_file>::iterator I = Modules.begin(),
- E = Modules.end(); I != E; ++I) {
- if (I->syms.empty())
+ MemoryBufferRef BufferRef(StringRef((const char *)View, Info.filesize),
+ Info.name);
+ ErrorOr<std::unique_ptr<object::FunctionIndexObjectFile>> ObjOrErr =
+ object::FunctionIndexObjectFile::create(BufferRef, diagnosticHandler);
+
+ if (std::error_code EC = ObjOrErr.getError())
+ message(LDPL_FATAL, "Could not read function index bitcode from file : %s",
+ EC.message().c_str());
+
+ object::FunctionIndexObjectFile &Obj = **ObjOrErr;
+
+ return Obj.takeIndex();
+}
+
+static std::unique_ptr<Module>
+getModuleForFile(LLVMContext &Context, claimed_file &F,
+ ld_plugin_input_file &Info, raw_fd_ostream *ApiFile,
+ StringSet<> &Internalize, StringSet<> &Maybe) {
+
+ if (get_symbols(F.handle, F.syms.size(), F.syms.data()) != LDPS_OK)
+ message(LDPL_FATAL, "Failed to get symbol information");
+
+ const void *View;
+ if (get_view(F.handle, &View) != LDPS_OK)
+ message(LDPL_FATAL, "Failed to get a view of file");
+
+ MemoryBufferRef BufferRef(StringRef((const char *)View, Info.filesize),
+ Info.name);
+ ErrorOr<std::unique_ptr<object::IRObjectFile>> ObjOrErr =
+ object::IRObjectFile::create(BufferRef, Context);
+
+ if (std::error_code EC = ObjOrErr.getError())
+ message(LDPL_FATAL, "Could not read bitcode from file : %s",
+ EC.message().c_str());
+
+ object::IRObjectFile &Obj = **ObjOrErr;
+
+ Module &M = Obj.getModule();
+
+ M.materializeMetadata();
+ UpgradeDebugInfo(M);
+
+ SmallPtrSet<GlobalValue *, 8> Used;
+ collectUsedGlobalVariables(M, Used, /*CompilerUsed*/ false);
+
+ DenseSet<GlobalValue *> Drop;
+ std::vector<GlobalAlias *> KeptAliases;
+
+ unsigned SymNum = 0;
+ for (auto &ObjSym : Obj.symbols()) {
+ if (shouldSkip(ObjSym.getFlags()))
+ continue;
+ ld_plugin_symbol &Sym = F.syms[SymNum];
+ ++SymNum;
+
+ ld_plugin_symbol_resolution Resolution =
+ (ld_plugin_symbol_resolution)Sym.resolution;
+
+ if (options::generate_api_file)
+ *ApiFile << Sym.name << ' ' << getResolutionName(Resolution) << '\n';
+
+ GlobalValue *GV = Obj.getSymbolGV(ObjSym.getRawDataRefImpl());
+ if (!GV) {
+ freeSymName(Sym);
+ continue; // Asm symbol.
+ }
+
+ if (Resolution != LDPR_PREVAILING_DEF_IRONLY && GV->hasCommonLinkage()) {
+ // Common linkage is special. There is no single symbol that wins the
+ // resolution. Instead we have to collect the maximum alignment and size.
+ // The IR linker does that for us if we just pass it every common GV.
+ // We still have to keep track of LDPR_PREVAILING_DEF_IRONLY so we
+ // internalize once the IR linker has done its job.
+ freeSymName(Sym);
continue;
- (*get_symbols)(I->handle, I->syms.size(), &I->syms[0]);
- for (unsigned i = 0, e = I->syms.size(); i != e; i++) {
- if (mustPreserve(*I, i)) {
- CodeGen->addMustPreserveSymbol(I->syms[i].name);
+ }
- if (options::generate_api_file)
- api_file << I->syms[i].name << "\n";
+ switch (Resolution) {
+ case LDPR_UNKNOWN:
+ llvm_unreachable("Unexpected resolution");
+
+ case LDPR_RESOLVED_IR:
+ case LDPR_RESOLVED_EXEC:
+ case LDPR_RESOLVED_DYN:
+ assert(GV->isDeclarationForLinker());
+ break;
+
+ case LDPR_UNDEF:
+ if (!GV->isDeclarationForLinker()) {
+ assert(GV->hasComdat());
+ Drop.insert(GV);
}
+ break;
+
+ case LDPR_PREVAILING_DEF_IRONLY: {
+ keepGlobalValue(*GV, KeptAliases);
+ if (!Used.count(GV)) {
+ // Since we use the regular lib/Linker, we cannot just internalize GV
+ // now or it will not be copied to the merged module. Instead we force
+ // it to be copied and then internalize it.
+ Internalize.insert(GV->getName());
+ }
+ break;
}
- }
- if (options::generate_api_file)
- api_file.close();
+ case LDPR_PREVAILING_DEF:
+ keepGlobalValue(*GV, KeptAliases);
+ break;
- CodeGen->setCodePICModel(output_type);
- CodeGen->setDebugInfo(LTO_DEBUG_MODEL_DWARF);
- if (!options::mcpu.empty())
- CodeGen->setCpu(options::mcpu.c_str());
+ case LDPR_PREEMPTED_IR:
+ // Gold might have selected a linkonce_odr and preempted a weak_odr.
+ // In that case we have to make sure we don't end up internalizing it.
+ if (!GV->isDiscardableIfUnused())
+ Maybe.erase(GV->getName());
- if (options::generate_bc_file != options::BC_NO) {
- std::string path;
- if (options::generate_bc_file == options::BC_ONLY)
- path = output_name;
- else if (!options::bc_path.empty())
- path = options::bc_path;
- else
- path = output_name + ".bc";
- std::string Error;
- if (!CodeGen->writeMergedModules(path.c_str(), Error))
- (*message)(LDPL_FATAL, "Failed to write the output file.");
- if (options::generate_bc_file == options::BC_ONLY) {
- delete CodeGen;
- exit(0);
+ // fall-through
+ case LDPR_PREEMPTED_REG:
+ Drop.insert(GV);
+ break;
+
+ case LDPR_PREVAILING_DEF_IRONLY_EXP: {
+ // We can only check for address uses after we merge the modules. The
+ // reason is that this GV might have a copy in another module
+ // and in that module the address might be significant, but that
+ // copy will be LDPR_PREEMPTED_IR.
+ if (GV->hasLinkOnceODRLinkage())
+ Maybe.insert(GV->getName());
+ keepGlobalValue(*GV, KeptAliases);
+ break;
+ }
}
+
+ freeSymName(Sym);
+ }
+
+ ValueToValueMapTy VM;
+ LocalValueMaterializer Materializer(Drop);
+ for (GlobalAlias *GA : KeptAliases) {
+ // Gold told us to keep GA. It is possible that a GV usied in the aliasee
+ // expression is being dropped. If that is the case, that GV must be copied.
+ Constant *Aliasee = GA->getAliasee();
+ Constant *Replacement = mapConstantToLocalCopy(Aliasee, VM, &Materializer);
+ GA->setAliasee(Replacement);
+ }
+
+ for (auto *GV : Drop)
+ drop(*GV);
+
+ return Obj.takeModule();
+}
+
+static void runLTOPasses(Module &M, TargetMachine &TM) {
+ M.setDataLayout(TM.createDataLayout());
+
+ legacy::PassManager passes;
+ passes.add(createTargetTransformInfoWrapperPass(TM.getTargetIRAnalysis()));
+
+ PassManagerBuilder PMB;
+ PMB.LibraryInfo = new TargetLibraryInfoImpl(Triple(TM.getTargetTriple()));
+ PMB.Inliner = createFunctionInliningPass();
+ // Unconditionally verify input since it is not verified before this
+ // point and has unknown origin.
+ PMB.VerifyInput = true;
+ PMB.VerifyOutput = !options::DisableVerify;
+ PMB.LoopVectorize = true;
+ PMB.SLPVectorize = true;
+ PMB.OptLevel = options::OptLevel;
+ PMB.populateLTOPassManager(passes);
+ passes.run(M);
+}
+
+static void saveBCFile(StringRef Path, Module &M) {
+ std::error_code EC;
+ raw_fd_ostream OS(Path, EC, sys::fs::OpenFlags::F_None);
+ if (EC)
+ message(LDPL_FATAL, "Failed to write the output file.");
+ WriteBitcodeToFile(&M, OS, /* ShouldPreserveUseListOrder */ true);
+}
+
+static void codegen(std::unique_ptr<Module> M) {
+ const std::string &TripleStr = M->getTargetTriple();
+ Triple TheTriple(TripleStr);
+
+ std::string ErrMsg;
+ const Target *TheTarget = TargetRegistry::lookupTarget(TripleStr, ErrMsg);
+ if (!TheTarget)
+ message(LDPL_FATAL, "Target not found: %s", ErrMsg.c_str());
+
+ if (unsigned NumOpts = options::extra.size())
+ cl::ParseCommandLineOptions(NumOpts, &options::extra[0]);
+
+ SubtargetFeatures Features;
+ Features.getDefaultSubtargetFeatures(TheTriple);
+ for (const std::string &A : MAttrs)
+ Features.AddFeature(A);
+
+ TargetOptions Options = InitTargetOptionsFromCodeGenFlags();
+ CodeGenOpt::Level CGOptLevel;
+ switch (options::OptLevel) {
+ case 0:
+ CGOptLevel = CodeGenOpt::None;
+ break;
+ case 1:
+ CGOptLevel = CodeGenOpt::Less;
+ break;
+ case 2:
+ CGOptLevel = CodeGenOpt::Default;
+ break;
+ case 3:
+ CGOptLevel = CodeGenOpt::Aggressive;
+ break;
}
+ std::unique_ptr<TargetMachine> TM(TheTarget->createTargetMachine(
+ TripleStr, options::mcpu, Features.getString(), Options, RelocationModel,
+ CodeModel::Default, CGOptLevel));
+
+ runLTOPasses(*M, *TM);
+
+ if (options::TheOutputType == options::OT_SAVE_TEMPS)
+ saveBCFile(output_name + ".opt.bc", *M);
- std::string ObjPath;
+ SmallString<128> Filename;
+ if (!options::obj_path.empty())
+ Filename = options::obj_path;
+ else if (options::TheOutputType == options::OT_SAVE_TEMPS)
+ Filename = output_name + ".o";
+
+ std::vector<SmallString<128>> Filenames(options::Parallelism);
+ bool TempOutFile = Filename.empty();
{
- const char *Temp;
- std::string Error;
- if (!CodeGen->compile_to_file(&Temp, /*DisableOpt*/ false, /*DisableInline*/
- false, /*DisableGVNLoadPRE*/ false, Error))
- (*message)(LDPL_ERROR, "Could not produce a combined object file\n");
- ObjPath = Temp;
+ // Open a file descriptor for each backend thread. This is done in a block
+ // so that the output file descriptors are closed before gold opens them.
+ std::list<llvm::raw_fd_ostream> OSs;
+ std::vector<llvm::raw_pwrite_stream *> OSPtrs(options::Parallelism);
+ for (unsigned I = 0; I != options::Parallelism; ++I) {
+ int FD;
+ if (TempOutFile) {
+ std::error_code EC =
+ sys::fs::createTemporaryFile("lto-llvm", "o", FD, Filenames[I]);
+ if (EC)
+ message(LDPL_FATAL, "Could not create temporary file: %s",
+ EC.message().c_str());
+ } else {
+ Filenames[I] = Filename;
+ if (options::Parallelism != 1)
+ Filenames[I] += utostr(I);
+ std::error_code EC =
+ sys::fs::openFileForWrite(Filenames[I], FD, sys::fs::F_None);
+ if (EC)
+ message(LDPL_FATAL, "Could not open file: %s", EC.message().c_str());
+ }
+ OSs.emplace_back(FD, true);
+ OSPtrs[I] = &OSs.back();
+ }
+
+ // Run backend threads.
+ splitCodeGen(std::move(M), OSPtrs, options::mcpu, Features.getString(),
+ Options, RelocationModel, CodeModel::Default, CGOptLevel);
+ }
+
+ for (auto &Filename : Filenames) {
+ if (add_input_file(Filename.c_str()) != LDPS_OK)
+ message(LDPL_FATAL,
+ "Unable to add .o file to the link. File left behind in: %s",
+ Filename.c_str());
+ if (TempOutFile)
+ Cleanup.push_back(Filename.c_str());
}
+}
- delete CodeGen;
- for (std::list<claimed_file>::iterator I = Modules.begin(),
- E = Modules.end(); I != E; ++I) {
- for (unsigned i = 0; i != I->syms.size(); ++i) {
- ld_plugin_symbol &sym = I->syms[i];
- free(sym.name);
+/// gold informs us that all symbols have been read. At this point, we use
+/// get_symbols to see if any of our definitions have been overridden by a
+/// native object file. Then, perform optimization and codegen.
+static ld_plugin_status allSymbolsReadHook(raw_fd_ostream *ApiFile) {
+ if (Modules.empty())
+ return LDPS_OK;
+
+ LLVMContext Context;
+ Context.setDiagnosticHandler(diagnosticHandlerForContext, nullptr, true);
+
+ // If we are doing ThinLTO compilation, simply build the combined
+ // function index/summary and emit it. We don't need to parse the modules
+ // and link them in this case.
+ if (options::thinlto) {
+ FunctionInfoIndex CombinedIndex;
+ uint64_t NextModuleId = 0;
+ for (claimed_file &F : Modules) {
+ ld_plugin_input_file File;
+ if (get_input_file(F.handle, &File) != LDPS_OK)
+ message(LDPL_FATAL, "Failed to get file information");
+
+ std::unique_ptr<FunctionInfoIndex> Index =
+ getFunctionIndexForFile(F, File);
+ CombinedIndex.mergeFrom(std::move(Index), ++NextModuleId);
}
+
+ std::error_code EC;
+ raw_fd_ostream OS(output_name + ".thinlto.bc", EC,
+ sys::fs::OpenFlags::F_None);
+ if (EC)
+ message(LDPL_FATAL, "Unable to open %s.thinlto.bc for writing: %s",
+ output_name.data(), EC.message().c_str());
+ WriteFunctionSummaryToFile(CombinedIndex, OS);
+ OS.close();
+
+ cleanup_hook();
+ exit(0);
}
- if ((*add_input_file)(ObjPath.c_str()) != LDPS_OK) {
- (*message)(LDPL_ERROR, "Unable to add .o file to the link.");
- (*message)(LDPL_ERROR, "File left behind in: %s", ObjPath.c_str());
- return LDPS_ERR;
+ std::unique_ptr<Module> Combined(new Module("ld-temp.o", Context));
+ Linker L(Combined.get());
+
+ std::string DefaultTriple = sys::getDefaultTargetTriple();
+
+ StringSet<> Internalize;
+ StringSet<> Maybe;
+ for (claimed_file &F : Modules) {
+ ld_plugin_input_file File;
+ if (get_input_file(F.handle, &File) != LDPS_OK)
+ message(LDPL_FATAL, "Failed to get file information");
+ std::unique_ptr<Module> M =
+ getModuleForFile(Context, F, File, ApiFile, Internalize, Maybe);
+ if (!options::triple.empty())
+ M->setTargetTriple(options::triple.c_str());
+ else if (M->getTargetTriple().empty()) {
+ M->setTargetTriple(DefaultTriple);
+ }
+
+ if (L.linkInModule(M.get()))
+ message(LDPL_FATAL, "Failed to link module");
+ if (release_input_file(F.handle) != LDPS_OK)
+ message(LDPL_FATAL, "Failed to release file information");
}
- if (!options::extra_library_path.empty() &&
- set_extra_library_path(options::extra_library_path.c_str()) != LDPS_OK) {
- (*message)(LDPL_ERROR, "Unable to set the extra library path.");
- return LDPS_ERR;
+ for (const auto &Name : Internalize) {
+ GlobalValue *GV = Combined->getNamedValue(Name.first());
+ if (GV)
+ internalize(*GV);
+ }
+
+ for (const auto &Name : Maybe) {
+ GlobalValue *GV = Combined->getNamedValue(Name.first());
+ if (!GV)
+ continue;
+ GV->setLinkage(GlobalValue::LinkOnceODRLinkage);
+ if (canBeOmittedFromSymbolTable(GV))
+ internalize(*GV);
+ }
+
+ if (options::TheOutputType == options::OT_DISABLE)
+ return LDPS_OK;
+
+ if (options::TheOutputType != options::OT_NORMAL) {
+ std::string path;
+ if (options::TheOutputType == options::OT_BC_ONLY)
+ path = output_name;
+ else
+ path = output_name + ".bc";
+ saveBCFile(path, *L.getModule());
+ if (options::TheOutputType == options::OT_BC_ONLY)
+ return LDPS_OK;
}
- if (options::obj_path.empty())
- Cleanup.push_back(ObjPath);
+ codegen(std::move(Combined));
+
+ if (!options::extra_library_path.empty() &&
+ set_extra_library_path(options::extra_library_path.c_str()) != LDPS_OK)
+ message(LDPL_FATAL, "Unable to set the extra library path.");
return LDPS_OK;
}
+static ld_plugin_status all_symbols_read_hook(void) {
+ ld_plugin_status Ret;
+ if (!options::generate_api_file) {
+ Ret = allSymbolsReadHook(nullptr);
+ } else {
+ std::error_code EC;
+ raw_fd_ostream ApiFile("apifile.txt", EC, sys::fs::F_None);
+ if (EC)
+ message(LDPL_FATAL, "Unable to open apifile.txt for writing: %s",
+ EC.message().c_str());
+ Ret = allSymbolsReadHook(&ApiFile);
+ }
+
+ llvm_shutdown();
+
+ if (options::TheOutputType == options::OT_BC_ONLY ||
+ options::TheOutputType == options::OT_DISABLE) {
+ if (options::TheOutputType == options::OT_DISABLE)
+ // Remove the output file here since ld.bfd creates the output file
+ // early.
+ sys::fs::remove(output_name);
+ exit(0);
+ }
+
+ return Ret;
+}
+
static ld_plugin_status cleanup_hook(void) {
- for (int i = 0, e = Cleanup.size(); i != e; ++i) {
- std::error_code EC = sys::fs::remove(Cleanup[i]);
+ for (std::string &Name : Cleanup) {
+ std::error_code EC = sys::fs::remove(Name);
if (EC)
- (*message)(LDPL_ERROR, "Failed to delete '%s': %s", Cleanup[i].c_str(),
- EC.message().c_str());
+ message(LDPL_ERROR, "Failed to delete '%s': %s", Name.c_str(),
+ EC.message().c_str());
}
return LDPS_OK;
projects / oota-llvm.git / blobdiff