| //===- ModuleSymbolTable.cpp - symbol table for in-memory IR --------------===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This class represents a symbol table built from in-memory IR. It provides |
| // access to GlobalValues and should only be used if such access is required |
| // (e.g. in the LTO implementation). |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Object/ModuleSymbolTable.h" |
| #include "RecordStreamer.h" |
| #include "llvm/ADT/STLExtras.h" |
| #include "llvm/ADT/SmallString.h" |
| #include "llvm/ADT/StringMap.h" |
| #include "llvm/ADT/StringRef.h" |
| #include "llvm/ADT/Triple.h" |
| #include "llvm/IR/Function.h" |
| #include "llvm/IR/GlobalAlias.h" |
| #include "llvm/IR/GlobalValue.h" |
| #include "llvm/IR/GlobalVariable.h" |
| #include "llvm/IR/InlineAsm.h" |
| #include "llvm/IR/Module.h" |
| #include "llvm/MC/MCAsmInfo.h" |
| #include "llvm/MC/MCContext.h" |
| #include "llvm/MC/MCDirectives.h" |
| #include "llvm/MC/MCInstrInfo.h" |
| #include "llvm/MC/MCObjectFileInfo.h" |
| #include "llvm/MC/MCParser/MCAsmParser.h" |
| #include "llvm/MC/MCParser/MCTargetAsmParser.h" |
| #include "llvm/MC/MCRegisterInfo.h" |
| #include "llvm/MC/MCSubtargetInfo.h" |
| #include "llvm/MC/MCSymbol.h" |
| #include "llvm/MC/MCTargetOptions.h" |
| #include "llvm/MC/TargetRegistry.h" |
| #include "llvm/Object/SymbolicFile.h" |
| #include "llvm/Support/Casting.h" |
| #include "llvm/Support/CodeGen.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/MemoryBuffer.h" |
| #include "llvm/Support/SMLoc.h" |
| #include "llvm/Support/SourceMgr.h" |
| #include "llvm/Support/raw_ostream.h" |
| #include <algorithm> |
| #include <cassert> |
| #include <cstdint> |
| #include <memory> |
| #include <string> |
| |
| using namespace llvm; |
| using namespace object; |
| |
| void ModuleSymbolTable::addModule(Module *M) { |
| if (FirstMod) |
| assert(FirstMod->getTargetTriple() == M->getTargetTriple()); |
| else |
| FirstMod = M; |
| |
| for (GlobalValue &GV : M->global_values()) |
| SymTab.push_back(&GV); |
| |
| CollectAsmSymbols(*M, [this](StringRef Name, BasicSymbolRef::Flags Flags) { |
| SymTab.push_back(new (AsmSymbols.Allocate()) |
| AsmSymbol(std::string(Name), Flags)); |
| }); |
| } |
| |
| static void |
| initializeRecordStreamer(const Module &M, |
| function_ref<void(RecordStreamer &)> Init) { |
| StringRef InlineAsm = M.getModuleInlineAsm(); |
| if (InlineAsm.empty()) |
| return; |
| |
| std::string Err; |
| const Triple TT(M.getTargetTriple()); |
| const Target *T = TargetRegistry::lookupTarget(TT.str(), Err); |
| assert(T && T->hasMCAsmParser()); |
| |
| std::unique_ptr<MCRegisterInfo> MRI(T->createMCRegInfo(TT.str())); |
| if (!MRI) |
| return; |
| |
| MCTargetOptions MCOptions; |
| std::unique_ptr<MCAsmInfo> MAI(T->createMCAsmInfo(*MRI, TT.str(), MCOptions)); |
| if (!MAI) |
| return; |
| |
| std::unique_ptr<MCSubtargetInfo> STI( |
| T->createMCSubtargetInfo(TT.str(), "", "")); |
| if (!STI) |
| return; |
| |
| std::unique_ptr<MCInstrInfo> MCII(T->createMCInstrInfo()); |
| if (!MCII) |
| return; |
| |
| std::unique_ptr<MemoryBuffer> Buffer(MemoryBuffer::getMemBuffer(InlineAsm)); |
| SourceMgr SrcMgr; |
| SrcMgr.AddNewSourceBuffer(std::move(Buffer), SMLoc()); |
| |
| MCContext MCCtx(TT, MAI.get(), MRI.get(), STI.get(), &SrcMgr); |
| std::unique_ptr<MCObjectFileInfo> MOFI( |
| T->createMCObjectFileInfo(MCCtx, /*PIC=*/false)); |
| MOFI->setSDKVersion(M.getSDKVersion()); |
| MCCtx.setObjectFileInfo(MOFI.get()); |
| RecordStreamer Streamer(MCCtx, M); |
| T->createNullTargetStreamer(Streamer); |
| |
| std::unique_ptr<MCAsmParser> Parser( |
| createMCAsmParser(SrcMgr, MCCtx, Streamer, *MAI)); |
| |
| std::unique_ptr<MCTargetAsmParser> TAP( |
| T->createMCAsmParser(*STI, *Parser, *MCII, MCOptions)); |
| if (!TAP) |
| return; |
| |
| // Module-level inline asm is assumed to use At&t syntax (see |
| // AsmPrinter::doInitialization()). |
| Parser->setAssemblerDialect(InlineAsm::AD_ATT); |
| |
| Parser->setTargetParser(*TAP); |
| if (Parser->Run(false)) |
| return; |
| |
| Init(Streamer); |
| } |
| |
| void ModuleSymbolTable::CollectAsmSymbols( |
| const Module &M, |
| function_ref<void(StringRef, BasicSymbolRef::Flags)> AsmSymbol) { |
| initializeRecordStreamer(M, [&](RecordStreamer &Streamer) { |
| Streamer.flushSymverDirectives(); |
| |
| for (auto &KV : Streamer) { |
| StringRef Key = KV.first(); |
| RecordStreamer::State Value = KV.second; |
| // FIXME: For now we just assume that all asm symbols are executable. |
| uint32_t Res = BasicSymbolRef::SF_Executable; |
| switch (Value) { |
| case RecordStreamer::NeverSeen: |
| llvm_unreachable("NeverSeen should have been replaced earlier"); |
| case RecordStreamer::DefinedGlobal: |
| Res |= BasicSymbolRef::SF_Global; |
| break; |
| case RecordStreamer::Defined: |
| break; |
| case RecordStreamer::Global: |
| case RecordStreamer::Used: |
| Res |= BasicSymbolRef::SF_Undefined; |
| Res |= BasicSymbolRef::SF_Global; |
| break; |
| case RecordStreamer::DefinedWeak: |
| Res |= BasicSymbolRef::SF_Weak; |
| Res |= BasicSymbolRef::SF_Global; |
| break; |
| case RecordStreamer::UndefinedWeak: |
| Res |= BasicSymbolRef::SF_Weak; |
| Res |= BasicSymbolRef::SF_Undefined; |
| } |
| AsmSymbol(Key, BasicSymbolRef::Flags(Res)); |
| } |
| }); |
| } |
| |
| void ModuleSymbolTable::CollectAsmSymvers( |
| const Module &M, function_ref<void(StringRef, StringRef)> AsmSymver) { |
| initializeRecordStreamer(M, [&](RecordStreamer &Streamer) { |
| for (auto &KV : Streamer.symverAliases()) |
| for (auto &Alias : KV.second) |
| AsmSymver(KV.first->getName(), Alias); |
| }); |
| } |
| |
| void ModuleSymbolTable::printSymbolName(raw_ostream &OS, Symbol S) const { |
| if (S.is<AsmSymbol *>()) { |
| OS << S.get<AsmSymbol *>()->first; |
| return; |
| } |
| |
| auto *GV = S.get<GlobalValue *>(); |
| if (GV->hasDLLImportStorageClass()) |
| OS << "__imp_"; |
| |
| Mang.getNameWithPrefix(OS, GV, false); |
| } |
| |
| uint32_t ModuleSymbolTable::getSymbolFlags(Symbol S) const { |
| if (S.is<AsmSymbol *>()) |
| return S.get<AsmSymbol *>()->second; |
| |
| auto *GV = S.get<GlobalValue *>(); |
| |
| uint32_t Res = BasicSymbolRef::SF_None; |
| if (GV->isDeclarationForLinker()) |
| Res |= BasicSymbolRef::SF_Undefined; |
| else if (GV->hasHiddenVisibility() && !GV->hasLocalLinkage()) |
| Res |= BasicSymbolRef::SF_Hidden; |
| if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV)) { |
| if (GVar->isConstant()) |
| Res |= BasicSymbolRef::SF_Const; |
| } |
| if (const GlobalObject *GO = GV->getAliaseeObject()) |
| if (isa<Function>(GO) || isa<GlobalIFunc>(GO)) |
| Res |= BasicSymbolRef::SF_Executable; |
| if (isa<GlobalAlias>(GV)) |
| Res |= BasicSymbolRef::SF_Indirect; |
| if (GV->hasPrivateLinkage()) |
| Res |= BasicSymbolRef::SF_FormatSpecific; |
| if (!GV->hasLocalLinkage()) |
| Res |= BasicSymbolRef::SF_Global; |
| if (GV->hasCommonLinkage()) |
| Res |= BasicSymbolRef::SF_Common; |
| if (GV->hasLinkOnceLinkage() || GV->hasWeakLinkage() || |
| GV->hasExternalWeakLinkage()) |
| Res |= BasicSymbolRef::SF_Weak; |
| |
| if (GV->getName().startswith("llvm.")) |
| Res |= BasicSymbolRef::SF_FormatSpecific; |
| else if (auto *Var = dyn_cast<GlobalVariable>(GV)) { |
| if (Var->getSection() == "llvm.metadata") |
| Res |= BasicSymbolRef::SF_FormatSpecific; |
| } |
| |
| return Res; |
| } |