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Diffstat (limited to 'contrib/llvm/lib/Object/IRSymtab.cpp')
| -rw-r--r-- | contrib/llvm/lib/Object/IRSymtab.cpp | 409 |
1 files changed, 0 insertions, 409 deletions
diff --git a/contrib/llvm/lib/Object/IRSymtab.cpp b/contrib/llvm/lib/Object/IRSymtab.cpp deleted file mode 100644 index e4282b9d6bd3..000000000000 --- a/contrib/llvm/lib/Object/IRSymtab.cpp +++ /dev/null @@ -1,409 +0,0 @@ -//===- IRSymtab.cpp - implementation of IR symbol tables ------------------===// -// -// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. -// See https://llvm.org/LICENSE.txt for license information. -// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception -// -//===----------------------------------------------------------------------===// - -#include "llvm/Object/IRSymtab.h" -#include "llvm/ADT/ArrayRef.h" -#include "llvm/ADT/DenseMap.h" -#include "llvm/ADT/SmallPtrSet.h" -#include "llvm/ADT/SmallString.h" -#include "llvm/ADT/SmallVector.h" -#include "llvm/ADT/StringRef.h" -#include "llvm/ADT/Triple.h" -#include "llvm/Config/llvm-config.h" -#include "llvm/IR/Comdat.h" -#include "llvm/IR/DataLayout.h" -#include "llvm/IR/GlobalAlias.h" -#include "llvm/IR/GlobalObject.h" -#include "llvm/IR/Mangler.h" -#include "llvm/IR/Metadata.h" -#include "llvm/IR/Module.h" -#include "llvm/Bitcode/BitcodeReader.h" -#include "llvm/MC/StringTableBuilder.h" -#include "llvm/Object/IRObjectFile.h" -#include "llvm/Object/ModuleSymbolTable.h" -#include "llvm/Object/SymbolicFile.h" -#include "llvm/Support/Allocator.h" -#include "llvm/Support/Casting.h" -#include "llvm/Support/Error.h" -#include "llvm/Support/StringSaver.h" -#include "llvm/Support/VCSRevision.h" -#include "llvm/Support/raw_ostream.h" -#include <cassert> -#include <string> -#include <utility> -#include <vector> - -using namespace llvm; -using namespace irsymtab; - -static const char *LibcallRoutineNames[] = { -#define HANDLE_LIBCALL(code, name) name, -#include "llvm/IR/RuntimeLibcalls.def" -#undef HANDLE_LIBCALL -}; - -namespace { - -const char *getExpectedProducerName() { - static char DefaultName[] = LLVM_VERSION_STRING -#ifdef LLVM_REVISION - " " LLVM_REVISION -#endif - ; - // Allows for testing of the irsymtab writer and upgrade mechanism. This - // environment variable should not be set by users. - if (char *OverrideName = getenv("LLVM_OVERRIDE_PRODUCER")) - return OverrideName; - return DefaultName; -} - -const char *kExpectedProducerName = getExpectedProducerName(); - -/// Stores the temporary state that is required to build an IR symbol table. -struct Builder { - SmallVector<char, 0> &Symtab; - StringTableBuilder &StrtabBuilder; - StringSaver Saver; - - // This ctor initializes a StringSaver using the passed in BumpPtrAllocator. - // The StringTableBuilder does not create a copy of any strings added to it, - // so this provides somewhere to store any strings that we create. - Builder(SmallVector<char, 0> &Symtab, StringTableBuilder &StrtabBuilder, - BumpPtrAllocator &Alloc) - : Symtab(Symtab), StrtabBuilder(StrtabBuilder), Saver(Alloc) {} - - DenseMap<const Comdat *, int> ComdatMap; - Mangler Mang; - Triple TT; - - std::vector<storage::Comdat> Comdats; - std::vector<storage::Module> Mods; - std::vector<storage::Symbol> Syms; - std::vector<storage::Uncommon> Uncommons; - - std::string COFFLinkerOpts; - raw_string_ostream COFFLinkerOptsOS{COFFLinkerOpts}; - - std::vector<storage::Str> DependentLibraries; - - void setStr(storage::Str &S, StringRef Value) { - S.Offset = StrtabBuilder.add(Value); - S.Size = Value.size(); - } - - template <typename T> - void writeRange(storage::Range<T> &R, const std::vector<T> &Objs) { - R.Offset = Symtab.size(); - R.Size = Objs.size(); - Symtab.insert(Symtab.end(), reinterpret_cast<const char *>(Objs.data()), - reinterpret_cast<const char *>(Objs.data() + Objs.size())); - } - - Expected<int> getComdatIndex(const Comdat *C, const Module *M); - - Error addModule(Module *M); - Error addSymbol(const ModuleSymbolTable &Msymtab, - const SmallPtrSet<GlobalValue *, 8> &Used, - ModuleSymbolTable::Symbol Sym); - - Error build(ArrayRef<Module *> Mods); -}; - -Error Builder::addModule(Module *M) { - if (M->getDataLayoutStr().empty()) - return make_error<StringError>("input module has no datalayout", - inconvertibleErrorCode()); - - SmallPtrSet<GlobalValue *, 8> Used; - collectUsedGlobalVariables(*M, Used, /*CompilerUsed*/ false); - - ModuleSymbolTable Msymtab; - Msymtab.addModule(M); - - storage::Module Mod; - Mod.Begin = Syms.size(); - Mod.End = Syms.size() + Msymtab.symbols().size(); - Mod.UncBegin = Uncommons.size(); - Mods.push_back(Mod); - - if (TT.isOSBinFormatCOFF()) { - if (auto E = M->materializeMetadata()) - return E; - if (NamedMDNode *LinkerOptions = - M->getNamedMetadata("llvm.linker.options")) { - for (MDNode *MDOptions : LinkerOptions->operands()) - for (const MDOperand &MDOption : cast<MDNode>(MDOptions)->operands()) - COFFLinkerOptsOS << " " << cast<MDString>(MDOption)->getString(); - } - } - - if (TT.isOSBinFormatELF()) { - if (auto E = M->materializeMetadata()) - return E; - if (NamedMDNode *N = M->getNamedMetadata("llvm.dependent-libraries")) { - for (MDNode *MDOptions : N->operands()) { - const auto OperandStr = - cast<MDString>(cast<MDNode>(MDOptions)->getOperand(0))->getString(); - storage::Str Specifier; - setStr(Specifier, OperandStr); - DependentLibraries.emplace_back(Specifier); - } - } - } - - for (ModuleSymbolTable::Symbol Msym : Msymtab.symbols()) - if (Error Err = addSymbol(Msymtab, Used, Msym)) - return Err; - - return Error::success(); -} - -Expected<int> Builder::getComdatIndex(const Comdat *C, const Module *M) { - auto P = ComdatMap.insert(std::make_pair(C, Comdats.size())); - if (P.second) { - std::string Name; - if (TT.isOSBinFormatCOFF()) { - const GlobalValue *GV = M->getNamedValue(C->getName()); - if (!GV) - return make_error<StringError>("Could not find leader", - inconvertibleErrorCode()); - // Internal leaders do not affect symbol resolution, therefore they do not - // appear in the symbol table. - if (GV->hasLocalLinkage()) { - P.first->second = -1; - return -1; - } - llvm::raw_string_ostream OS(Name); - Mang.getNameWithPrefix(OS, GV, false); - } else { - Name = C->getName(); - } - - storage::Comdat Comdat; - setStr(Comdat.Name, Saver.save(Name)); - Comdats.push_back(Comdat); - } - - return P.first->second; -} - -Error Builder::addSymbol(const ModuleSymbolTable &Msymtab, - const SmallPtrSet<GlobalValue *, 8> &Used, - ModuleSymbolTable::Symbol Msym) { - Syms.emplace_back(); - storage::Symbol &Sym = Syms.back(); - Sym = {}; - - storage::Uncommon *Unc = nullptr; - auto Uncommon = [&]() -> storage::Uncommon & { - if (Unc) - return *Unc; - Sym.Flags |= 1 << storage::Symbol::FB_has_uncommon; - Uncommons.emplace_back(); - Unc = &Uncommons.back(); - *Unc = {}; - setStr(Unc->COFFWeakExternFallbackName, ""); - setStr(Unc->SectionName, ""); - return *Unc; - }; - - SmallString<64> Name; - { - raw_svector_ostream OS(Name); - Msymtab.printSymbolName(OS, Msym); - } - setStr(Sym.Name, Saver.save(StringRef(Name))); - - auto Flags = Msymtab.getSymbolFlags(Msym); - if (Flags & object::BasicSymbolRef::SF_Undefined) - Sym.Flags |= 1 << storage::Symbol::FB_undefined; - if (Flags & object::BasicSymbolRef::SF_Weak) - Sym.Flags |= 1 << storage::Symbol::FB_weak; - if (Flags & object::BasicSymbolRef::SF_Common) - Sym.Flags |= 1 << storage::Symbol::FB_common; - if (Flags & object::BasicSymbolRef::SF_Indirect) - Sym.Flags |= 1 << storage::Symbol::FB_indirect; - if (Flags & object::BasicSymbolRef::SF_Global) - Sym.Flags |= 1 << storage::Symbol::FB_global; - if (Flags & object::BasicSymbolRef::SF_FormatSpecific) - Sym.Flags |= 1 << storage::Symbol::FB_format_specific; - if (Flags & object::BasicSymbolRef::SF_Executable) - Sym.Flags |= 1 << storage::Symbol::FB_executable; - - Sym.ComdatIndex = -1; - auto *GV = Msym.dyn_cast<GlobalValue *>(); - if (!GV) { - // Undefined module asm symbols act as GC roots and are implicitly used. - if (Flags & object::BasicSymbolRef::SF_Undefined) - Sym.Flags |= 1 << storage::Symbol::FB_used; - setStr(Sym.IRName, ""); - return Error::success(); - } - - setStr(Sym.IRName, GV->getName()); - - bool IsBuiltinFunc = false; - - for (const char *LibcallName : LibcallRoutineNames) - if (GV->getName() == LibcallName) - IsBuiltinFunc = true; - - if (Used.count(GV) || IsBuiltinFunc) - Sym.Flags |= 1 << storage::Symbol::FB_used; - if (GV->isThreadLocal()) - Sym.Flags |= 1 << storage::Symbol::FB_tls; - if (GV->hasGlobalUnnamedAddr()) - Sym.Flags |= 1 << storage::Symbol::FB_unnamed_addr; - if (GV->canBeOmittedFromSymbolTable()) - Sym.Flags |= 1 << storage::Symbol::FB_may_omit; - Sym.Flags |= unsigned(GV->getVisibility()) << storage::Symbol::FB_visibility; - - if (Flags & object::BasicSymbolRef::SF_Common) { - Uncommon().CommonSize = GV->getParent()->getDataLayout().getTypeAllocSize( - GV->getType()->getElementType()); - Uncommon().CommonAlign = GV->getAlignment(); - } - - const GlobalObject *Base = GV->getBaseObject(); - if (!Base) - return make_error<StringError>("Unable to determine comdat of alias!", - inconvertibleErrorCode()); - if (const Comdat *C = Base->getComdat()) { - Expected<int> ComdatIndexOrErr = getComdatIndex(C, GV->getParent()); - if (!ComdatIndexOrErr) - return ComdatIndexOrErr.takeError(); - Sym.ComdatIndex = *ComdatIndexOrErr; - } - - if (TT.isOSBinFormatCOFF()) { - emitLinkerFlagsForGlobalCOFF(COFFLinkerOptsOS, GV, TT, Mang); - - if ((Flags & object::BasicSymbolRef::SF_Weak) && - (Flags & object::BasicSymbolRef::SF_Indirect)) { - auto *Fallback = dyn_cast<GlobalValue>( - cast<GlobalAlias>(GV)->getAliasee()->stripPointerCasts()); - if (!Fallback) - return make_error<StringError>("Invalid weak external", - inconvertibleErrorCode()); - std::string FallbackName; - raw_string_ostream OS(FallbackName); - Msymtab.printSymbolName(OS, Fallback); - OS.flush(); - setStr(Uncommon().COFFWeakExternFallbackName, Saver.save(FallbackName)); - } - } - - if (!Base->getSection().empty()) - setStr(Uncommon().SectionName, Saver.save(Base->getSection())); - - return Error::success(); -} - -Error Builder::build(ArrayRef<Module *> IRMods) { - storage::Header Hdr; - - assert(!IRMods.empty()); - Hdr.Version = storage::Header::kCurrentVersion; - setStr(Hdr.Producer, kExpectedProducerName); - setStr(Hdr.TargetTriple, IRMods[0]->getTargetTriple()); - setStr(Hdr.SourceFileName, IRMods[0]->getSourceFileName()); - TT = Triple(IRMods[0]->getTargetTriple()); - - for (auto *M : IRMods) - if (Error Err = addModule(M)) - return Err; - - COFFLinkerOptsOS.flush(); - setStr(Hdr.COFFLinkerOpts, Saver.save(COFFLinkerOpts)); - - // We are about to fill in the header's range fields, so reserve space for it - // and copy it in afterwards. - Symtab.resize(sizeof(storage::Header)); - writeRange(Hdr.Modules, Mods); - writeRange(Hdr.Comdats, Comdats); - writeRange(Hdr.Symbols, Syms); - writeRange(Hdr.Uncommons, Uncommons); - writeRange(Hdr.DependentLibraries, DependentLibraries); - *reinterpret_cast<storage::Header *>(Symtab.data()) = Hdr; - return Error::success(); -} - -} // end anonymous namespace - -Error irsymtab::build(ArrayRef<Module *> Mods, SmallVector<char, 0> &Symtab, - StringTableBuilder &StrtabBuilder, - BumpPtrAllocator &Alloc) { - return Builder(Symtab, StrtabBuilder, Alloc).build(Mods); -} - -// Upgrade a vector of bitcode modules created by an old version of LLVM by -// creating an irsymtab for them in the current format. -static Expected<FileContents> upgrade(ArrayRef<BitcodeModule> BMs) { - FileContents FC; - - LLVMContext Ctx; - std::vector<Module *> Mods; - std::vector<std::unique_ptr<Module>> OwnedMods; - for (auto BM : BMs) { - Expected<std::unique_ptr<Module>> MOrErr = - BM.getLazyModule(Ctx, /*ShouldLazyLoadMetadata*/ true, - /*IsImporting*/ false); - if (!MOrErr) - return MOrErr.takeError(); - - Mods.push_back(MOrErr->get()); - OwnedMods.push_back(std::move(*MOrErr)); - } - - StringTableBuilder StrtabBuilder(StringTableBuilder::RAW); - BumpPtrAllocator Alloc; - if (Error E = build(Mods, FC.Symtab, StrtabBuilder, Alloc)) - return std::move(E); - - StrtabBuilder.finalizeInOrder(); - FC.Strtab.resize(StrtabBuilder.getSize()); - StrtabBuilder.write((uint8_t *)FC.Strtab.data()); - - FC.TheReader = {{FC.Symtab.data(), FC.Symtab.size()}, - {FC.Strtab.data(), FC.Strtab.size()}}; - return std::move(FC); -} - -Expected<FileContents> irsymtab::readBitcode(const BitcodeFileContents &BFC) { - if (BFC.Mods.empty()) - return make_error<StringError>("Bitcode file does not contain any modules", - inconvertibleErrorCode()); - - if (BFC.StrtabForSymtab.empty() || - BFC.Symtab.size() < sizeof(storage::Header)) - return upgrade(BFC.Mods); - - // We cannot use the regular reader to read the version and producer, because - // it will expect the header to be in the current format. The only thing we - // can rely on is that the version and producer will be present as the first - // struct elements. - auto *Hdr = reinterpret_cast<const storage::Header *>(BFC.Symtab.data()); - unsigned Version = Hdr->Version; - StringRef Producer = Hdr->Producer.get(BFC.StrtabForSymtab); - if (Version != storage::Header::kCurrentVersion || - Producer != kExpectedProducerName) - return upgrade(BFC.Mods); - - FileContents FC; - FC.TheReader = {{BFC.Symtab.data(), BFC.Symtab.size()}, - {BFC.StrtabForSymtab.data(), BFC.StrtabForSymtab.size()}}; - - // Finally, make sure that the number of modules in the symbol table matches - // the number of modules in the bitcode file. If they differ, it may mean that - // the bitcode file was created by binary concatenation, so we need to create - // a new symbol table from scratch. - if (FC.TheReader.getNumModules() != BFC.Mods.size()) - return upgrade(std::move(BFC.Mods)); - - return std::move(FC); -} |