diff options
author | Dimitry Andric <dim@FreeBSD.org> | 2019-12-20 19:53:05 +0000 |
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committer | Dimitry Andric <dim@FreeBSD.org> | 2019-12-20 19:53:05 +0000 |
commit | 0b57cec536236d46e3dba9bd041533462f33dbb7 (patch) | |
tree | 56229dbdbbf76d18580f72f789003db17246c8d9 /contrib/llvm-project/llvm/lib/IR/Module.cpp | |
parent | 718ef55ec7785aae63f98f8ca05dc07ed399c16d (diff) |
Notes
Diffstat (limited to 'contrib/llvm-project/llvm/lib/IR/Module.cpp')
-rw-r--r-- | contrib/llvm-project/llvm/lib/IR/Module.cpp | 611 |
1 files changed, 611 insertions, 0 deletions
diff --git a/contrib/llvm-project/llvm/lib/IR/Module.cpp b/contrib/llvm-project/llvm/lib/IR/Module.cpp new file mode 100644 index 000000000000..dbf4035ac7c1 --- /dev/null +++ b/contrib/llvm-project/llvm/lib/IR/Module.cpp @@ -0,0 +1,611 @@ +//===- Module.cpp - Implement the Module class ----------------------------===// +// +// 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 file implements the Module class for the IR library. +// +//===----------------------------------------------------------------------===// + +#include "llvm/IR/Module.h" +#include "SymbolTableListTraitsImpl.h" +#include "llvm/ADT/Optional.h" +#include "llvm/ADT/SmallPtrSet.h" +#include "llvm/ADT/SmallString.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/ADT/StringMap.h" +#include "llvm/ADT/StringRef.h" +#include "llvm/ADT/Twine.h" +#include "llvm/IR/Attributes.h" +#include "llvm/IR/Comdat.h" +#include "llvm/IR/Constants.h" +#include "llvm/IR/DataLayout.h" +#include "llvm/IR/DebugInfoMetadata.h" +#include "llvm/IR/DerivedTypes.h" +#include "llvm/IR/Function.h" +#include "llvm/IR/GVMaterializer.h" +#include "llvm/IR/GlobalAlias.h" +#include "llvm/IR/GlobalIFunc.h" +#include "llvm/IR/GlobalValue.h" +#include "llvm/IR/GlobalVariable.h" +#include "llvm/IR/LLVMContext.h" +#include "llvm/IR/Metadata.h" +#include "llvm/IR/SymbolTableListTraits.h" +#include "llvm/IR/Type.h" +#include "llvm/IR/TypeFinder.h" +#include "llvm/IR/Value.h" +#include "llvm/IR/ValueSymbolTable.h" +#include "llvm/Pass.h" +#include "llvm/Support/Casting.h" +#include "llvm/Support/CodeGen.h" +#include "llvm/Support/Error.h" +#include "llvm/Support/MemoryBuffer.h" +#include "llvm/Support/Path.h" +#include "llvm/Support/RandomNumberGenerator.h" +#include "llvm/Support/VersionTuple.h" +#include <algorithm> +#include <cassert> +#include <cstdint> +#include <memory> +#include <utility> +#include <vector> + +using namespace llvm; + +//===----------------------------------------------------------------------===// +// Methods to implement the globals and functions lists. +// + +// Explicit instantiations of SymbolTableListTraits since some of the methods +// are not in the public header file. +template class llvm::SymbolTableListTraits<Function>; +template class llvm::SymbolTableListTraits<GlobalVariable>; +template class llvm::SymbolTableListTraits<GlobalAlias>; +template class llvm::SymbolTableListTraits<GlobalIFunc>; + +//===----------------------------------------------------------------------===// +// Primitive Module methods. +// + +Module::Module(StringRef MID, LLVMContext &C) + : Context(C), Materializer(), ModuleID(MID), SourceFileName(MID), DL("") { + ValSymTab = new ValueSymbolTable(); + NamedMDSymTab = new StringMap<NamedMDNode *>(); + Context.addModule(this); +} + +Module::~Module() { + Context.removeModule(this); + dropAllReferences(); + GlobalList.clear(); + FunctionList.clear(); + AliasList.clear(); + IFuncList.clear(); + NamedMDList.clear(); + delete ValSymTab; + delete static_cast<StringMap<NamedMDNode *> *>(NamedMDSymTab); +} + +std::unique_ptr<RandomNumberGenerator> Module::createRNG(const Pass* P) const { + SmallString<32> Salt(P->getPassName()); + + // This RNG is guaranteed to produce the same random stream only + // when the Module ID and thus the input filename is the same. This + // might be problematic if the input filename extension changes + // (e.g. from .c to .bc or .ll). + // + // We could store this salt in NamedMetadata, but this would make + // the parameter non-const. This would unfortunately make this + // interface unusable by any Machine passes, since they only have a + // const reference to their IR Module. Alternatively we can always + // store salt metadata from the Module constructor. + Salt += sys::path::filename(getModuleIdentifier()); + + return std::unique_ptr<RandomNumberGenerator>(new RandomNumberGenerator(Salt)); +} + +/// getNamedValue - Return the first global value in the module with +/// the specified name, of arbitrary type. This method returns null +/// if a global with the specified name is not found. +GlobalValue *Module::getNamedValue(StringRef Name) const { + return cast_or_null<GlobalValue>(getValueSymbolTable().lookup(Name)); +} + +/// getMDKindID - Return a unique non-zero ID for the specified metadata kind. +/// This ID is uniqued across modules in the current LLVMContext. +unsigned Module::getMDKindID(StringRef Name) const { + return Context.getMDKindID(Name); +} + +/// getMDKindNames - Populate client supplied SmallVector with the name for +/// custom metadata IDs registered in this LLVMContext. ID #0 is not used, +/// so it is filled in as an empty string. +void Module::getMDKindNames(SmallVectorImpl<StringRef> &Result) const { + return Context.getMDKindNames(Result); +} + +void Module::getOperandBundleTags(SmallVectorImpl<StringRef> &Result) const { + return Context.getOperandBundleTags(Result); +} + +//===----------------------------------------------------------------------===// +// Methods for easy access to the functions in the module. +// + +// getOrInsertFunction - Look up the specified function in the module symbol +// table. If it does not exist, add a prototype for the function and return +// it. This is nice because it allows most passes to get away with not handling +// the symbol table directly for this common task. +// +FunctionCallee Module::getOrInsertFunction(StringRef Name, FunctionType *Ty, + AttributeList AttributeList) { + // See if we have a definition for the specified function already. + GlobalValue *F = getNamedValue(Name); + if (!F) { + // Nope, add it + Function *New = Function::Create(Ty, GlobalVariable::ExternalLinkage, + DL.getProgramAddressSpace(), Name); + if (!New->isIntrinsic()) // Intrinsics get attrs set on construction + New->setAttributes(AttributeList); + FunctionList.push_back(New); + return {Ty, New}; // Return the new prototype. + } + + // If the function exists but has the wrong type, return a bitcast to the + // right type. + auto *PTy = PointerType::get(Ty, F->getAddressSpace()); + if (F->getType() != PTy) + return {Ty, ConstantExpr::getBitCast(F, PTy)}; + + // Otherwise, we just found the existing function or a prototype. + return {Ty, F}; +} + +FunctionCallee Module::getOrInsertFunction(StringRef Name, FunctionType *Ty) { + return getOrInsertFunction(Name, Ty, AttributeList()); +} + +// getFunction - Look up the specified function in the module symbol table. +// If it does not exist, return null. +// +Function *Module::getFunction(StringRef Name) const { + return dyn_cast_or_null<Function>(getNamedValue(Name)); +} + +//===----------------------------------------------------------------------===// +// Methods for easy access to the global variables in the module. +// + +/// getGlobalVariable - Look up the specified global variable in the module +/// symbol table. If it does not exist, return null. The type argument +/// should be the underlying type of the global, i.e., it should not have +/// the top-level PointerType, which represents the address of the global. +/// If AllowLocal is set to true, this function will return types that +/// have an local. By default, these types are not returned. +/// +GlobalVariable *Module::getGlobalVariable(StringRef Name, + bool AllowLocal) const { + if (GlobalVariable *Result = + dyn_cast_or_null<GlobalVariable>(getNamedValue(Name))) + if (AllowLocal || !Result->hasLocalLinkage()) + return Result; + return nullptr; +} + +/// getOrInsertGlobal - Look up the specified global in the module symbol table. +/// 1. If it does not exist, add a declaration of the global and return it. +/// 2. Else, the global exists but has the wrong type: return the function +/// with a constantexpr cast to the right type. +/// 3. Finally, if the existing global is the correct declaration, return the +/// existing global. +Constant *Module::getOrInsertGlobal( + StringRef Name, Type *Ty, + function_ref<GlobalVariable *()> CreateGlobalCallback) { + // See if we have a definition for the specified global already. + GlobalVariable *GV = dyn_cast_or_null<GlobalVariable>(getNamedValue(Name)); + if (!GV) + GV = CreateGlobalCallback(); + assert(GV && "The CreateGlobalCallback is expected to create a global"); + + // If the variable exists but has the wrong type, return a bitcast to the + // right type. + Type *GVTy = GV->getType(); + PointerType *PTy = PointerType::get(Ty, GVTy->getPointerAddressSpace()); + if (GVTy != PTy) + return ConstantExpr::getBitCast(GV, PTy); + + // Otherwise, we just found the existing function or a prototype. + return GV; +} + +// Overload to construct a global variable using its constructor's defaults. +Constant *Module::getOrInsertGlobal(StringRef Name, Type *Ty) { + return getOrInsertGlobal(Name, Ty, [&] { + return new GlobalVariable(*this, Ty, false, GlobalVariable::ExternalLinkage, + nullptr, Name); + }); +} + +//===----------------------------------------------------------------------===// +// Methods for easy access to the global variables in the module. +// + +// getNamedAlias - Look up the specified global in the module symbol table. +// If it does not exist, return null. +// +GlobalAlias *Module::getNamedAlias(StringRef Name) const { + return dyn_cast_or_null<GlobalAlias>(getNamedValue(Name)); +} + +GlobalIFunc *Module::getNamedIFunc(StringRef Name) const { + return dyn_cast_or_null<GlobalIFunc>(getNamedValue(Name)); +} + +/// getNamedMetadata - Return the first NamedMDNode in the module with the +/// specified name. This method returns null if a NamedMDNode with the +/// specified name is not found. +NamedMDNode *Module::getNamedMetadata(const Twine &Name) const { + SmallString<256> NameData; + StringRef NameRef = Name.toStringRef(NameData); + return static_cast<StringMap<NamedMDNode*> *>(NamedMDSymTab)->lookup(NameRef); +} + +/// getOrInsertNamedMetadata - Return the first named MDNode in the module +/// with the specified name. This method returns a new NamedMDNode if a +/// NamedMDNode with the specified name is not found. +NamedMDNode *Module::getOrInsertNamedMetadata(StringRef Name) { + NamedMDNode *&NMD = + (*static_cast<StringMap<NamedMDNode *> *>(NamedMDSymTab))[Name]; + if (!NMD) { + NMD = new NamedMDNode(Name); + NMD->setParent(this); + NamedMDList.push_back(NMD); + } + return NMD; +} + +/// eraseNamedMetadata - Remove the given NamedMDNode from this module and +/// delete it. +void Module::eraseNamedMetadata(NamedMDNode *NMD) { + static_cast<StringMap<NamedMDNode *> *>(NamedMDSymTab)->erase(NMD->getName()); + NamedMDList.erase(NMD->getIterator()); +} + +bool Module::isValidModFlagBehavior(Metadata *MD, ModFlagBehavior &MFB) { + if (ConstantInt *Behavior = mdconst::dyn_extract_or_null<ConstantInt>(MD)) { + uint64_t Val = Behavior->getLimitedValue(); + if (Val >= ModFlagBehaviorFirstVal && Val <= ModFlagBehaviorLastVal) { + MFB = static_cast<ModFlagBehavior>(Val); + return true; + } + } + return false; +} + +/// getModuleFlagsMetadata - Returns the module flags in the provided vector. +void Module:: +getModuleFlagsMetadata(SmallVectorImpl<ModuleFlagEntry> &Flags) const { + const NamedMDNode *ModFlags = getModuleFlagsMetadata(); + if (!ModFlags) return; + + for (const MDNode *Flag : ModFlags->operands()) { + ModFlagBehavior MFB; + if (Flag->getNumOperands() >= 3 && + isValidModFlagBehavior(Flag->getOperand(0), MFB) && + dyn_cast_or_null<MDString>(Flag->getOperand(1))) { + // Check the operands of the MDNode before accessing the operands. + // The verifier will actually catch these failures. + MDString *Key = cast<MDString>(Flag->getOperand(1)); + Metadata *Val = Flag->getOperand(2); + Flags.push_back(ModuleFlagEntry(MFB, Key, Val)); + } + } +} + +/// Return the corresponding value if Key appears in module flags, otherwise +/// return null. +Metadata *Module::getModuleFlag(StringRef Key) const { + SmallVector<Module::ModuleFlagEntry, 8> ModuleFlags; + getModuleFlagsMetadata(ModuleFlags); + for (const ModuleFlagEntry &MFE : ModuleFlags) { + if (Key == MFE.Key->getString()) + return MFE.Val; + } + return nullptr; +} + +/// getModuleFlagsMetadata - Returns the NamedMDNode in the module that +/// represents module-level flags. This method returns null if there are no +/// module-level flags. +NamedMDNode *Module::getModuleFlagsMetadata() const { + return getNamedMetadata("llvm.module.flags"); +} + +/// getOrInsertModuleFlagsMetadata - Returns the NamedMDNode in the module that +/// represents module-level flags. If module-level flags aren't found, it +/// creates the named metadata that contains them. +NamedMDNode *Module::getOrInsertModuleFlagsMetadata() { + return getOrInsertNamedMetadata("llvm.module.flags"); +} + +/// addModuleFlag - Add a module-level flag to the module-level flags +/// metadata. It will create the module-level flags named metadata if it doesn't +/// already exist. +void Module::addModuleFlag(ModFlagBehavior Behavior, StringRef Key, + Metadata *Val) { + Type *Int32Ty = Type::getInt32Ty(Context); + Metadata *Ops[3] = { + ConstantAsMetadata::get(ConstantInt::get(Int32Ty, Behavior)), + MDString::get(Context, Key), Val}; + getOrInsertModuleFlagsMetadata()->addOperand(MDNode::get(Context, Ops)); +} +void Module::addModuleFlag(ModFlagBehavior Behavior, StringRef Key, + Constant *Val) { + addModuleFlag(Behavior, Key, ConstantAsMetadata::get(Val)); +} +void Module::addModuleFlag(ModFlagBehavior Behavior, StringRef Key, + uint32_t Val) { + Type *Int32Ty = Type::getInt32Ty(Context); + addModuleFlag(Behavior, Key, ConstantInt::get(Int32Ty, Val)); +} +void Module::addModuleFlag(MDNode *Node) { + assert(Node->getNumOperands() == 3 && + "Invalid number of operands for module flag!"); + assert(mdconst::hasa<ConstantInt>(Node->getOperand(0)) && + isa<MDString>(Node->getOperand(1)) && + "Invalid operand types for module flag!"); + getOrInsertModuleFlagsMetadata()->addOperand(Node); +} + +void Module::setDataLayout(StringRef Desc) { + DL.reset(Desc); +} + +void Module::setDataLayout(const DataLayout &Other) { DL = Other; } + +const DataLayout &Module::getDataLayout() const { return DL; } + +DICompileUnit *Module::debug_compile_units_iterator::operator*() const { + return cast<DICompileUnit>(CUs->getOperand(Idx)); +} +DICompileUnit *Module::debug_compile_units_iterator::operator->() const { + return cast<DICompileUnit>(CUs->getOperand(Idx)); +} + +void Module::debug_compile_units_iterator::SkipNoDebugCUs() { + while (CUs && (Idx < CUs->getNumOperands()) && + ((*this)->getEmissionKind() == DICompileUnit::NoDebug)) + ++Idx; +} + +//===----------------------------------------------------------------------===// +// Methods to control the materialization of GlobalValues in the Module. +// +void Module::setMaterializer(GVMaterializer *GVM) { + assert(!Materializer && + "Module already has a GVMaterializer. Call materializeAll" + " to clear it out before setting another one."); + Materializer.reset(GVM); +} + +Error Module::materialize(GlobalValue *GV) { + if (!Materializer) + return Error::success(); + + return Materializer->materialize(GV); +} + +Error Module::materializeAll() { + if (!Materializer) + return Error::success(); + std::unique_ptr<GVMaterializer> M = std::move(Materializer); + return M->materializeModule(); +} + +Error Module::materializeMetadata() { + if (!Materializer) + return Error::success(); + return Materializer->materializeMetadata(); +} + +//===----------------------------------------------------------------------===// +// Other module related stuff. +// + +std::vector<StructType *> Module::getIdentifiedStructTypes() const { + // If we have a materializer, it is possible that some unread function + // uses a type that is currently not visible to a TypeFinder, so ask + // the materializer which types it created. + if (Materializer) + return Materializer->getIdentifiedStructTypes(); + + std::vector<StructType *> Ret; + TypeFinder SrcStructTypes; + SrcStructTypes.run(*this, true); + Ret.assign(SrcStructTypes.begin(), SrcStructTypes.end()); + return Ret; +} + +// dropAllReferences() - This function causes all the subelements to "let go" +// of all references that they are maintaining. This allows one to 'delete' a +// whole module at a time, even though there may be circular references... first +// all references are dropped, and all use counts go to zero. Then everything +// is deleted for real. Note that no operations are valid on an object that +// has "dropped all references", except operator delete. +// +void Module::dropAllReferences() { + for (Function &F : *this) + F.dropAllReferences(); + + for (GlobalVariable &GV : globals()) + GV.dropAllReferences(); + + for (GlobalAlias &GA : aliases()) + GA.dropAllReferences(); + + for (GlobalIFunc &GIF : ifuncs()) + GIF.dropAllReferences(); +} + +unsigned Module::getNumberRegisterParameters() const { + auto *Val = + cast_or_null<ConstantAsMetadata>(getModuleFlag("NumRegisterParameters")); + if (!Val) + return 0; + return cast<ConstantInt>(Val->getValue())->getZExtValue(); +} + +unsigned Module::getDwarfVersion() const { + auto *Val = cast_or_null<ConstantAsMetadata>(getModuleFlag("Dwarf Version")); + if (!Val) + return 0; + return cast<ConstantInt>(Val->getValue())->getZExtValue(); +} + +unsigned Module::getCodeViewFlag() const { + auto *Val = cast_or_null<ConstantAsMetadata>(getModuleFlag("CodeView")); + if (!Val) + return 0; + return cast<ConstantInt>(Val->getValue())->getZExtValue(); +} + +unsigned Module::getInstructionCount() { + unsigned NumInstrs = 0; + for (Function &F : FunctionList) + NumInstrs += F.getInstructionCount(); + return NumInstrs; +} + +Comdat *Module::getOrInsertComdat(StringRef Name) { + auto &Entry = *ComdatSymTab.insert(std::make_pair(Name, Comdat())).first; + Entry.second.Name = &Entry; + return &Entry.second; +} + +PICLevel::Level Module::getPICLevel() const { + auto *Val = cast_or_null<ConstantAsMetadata>(getModuleFlag("PIC Level")); + + if (!Val) + return PICLevel::NotPIC; + + return static_cast<PICLevel::Level>( + cast<ConstantInt>(Val->getValue())->getZExtValue()); +} + +void Module::setPICLevel(PICLevel::Level PL) { + addModuleFlag(ModFlagBehavior::Max, "PIC Level", PL); +} + +PIELevel::Level Module::getPIELevel() const { + auto *Val = cast_or_null<ConstantAsMetadata>(getModuleFlag("PIE Level")); + + if (!Val) + return PIELevel::Default; + + return static_cast<PIELevel::Level>( + cast<ConstantInt>(Val->getValue())->getZExtValue()); +} + +void Module::setPIELevel(PIELevel::Level PL) { + addModuleFlag(ModFlagBehavior::Max, "PIE Level", PL); +} + +Optional<CodeModel::Model> Module::getCodeModel() const { + auto *Val = cast_or_null<ConstantAsMetadata>(getModuleFlag("Code Model")); + + if (!Val) + return None; + + return static_cast<CodeModel::Model>( + cast<ConstantInt>(Val->getValue())->getZExtValue()); +} + +void Module::setCodeModel(CodeModel::Model CL) { + // Linking object files with different code models is undefined behavior + // because the compiler would have to generate additional code (to span + // longer jumps) if a larger code model is used with a smaller one. + // Therefore we will treat attempts to mix code models as an error. + addModuleFlag(ModFlagBehavior::Error, "Code Model", CL); +} + +void Module::setProfileSummary(Metadata *M, ProfileSummary::Kind Kind) { + if (Kind == ProfileSummary::PSK_CSInstr) + addModuleFlag(ModFlagBehavior::Error, "CSProfileSummary", M); + else + addModuleFlag(ModFlagBehavior::Error, "ProfileSummary", M); +} + +Metadata *Module::getProfileSummary(bool IsCS) { + return (IsCS ? getModuleFlag("CSProfileSummary") + : getModuleFlag("ProfileSummary")); +} + +void Module::setOwnedMemoryBuffer(std::unique_ptr<MemoryBuffer> MB) { + OwnedMemoryBuffer = std::move(MB); +} + +bool Module::getRtLibUseGOT() const { + auto *Val = cast_or_null<ConstantAsMetadata>(getModuleFlag("RtLibUseGOT")); + return Val && (cast<ConstantInt>(Val->getValue())->getZExtValue() > 0); +} + +void Module::setRtLibUseGOT() { + addModuleFlag(ModFlagBehavior::Max, "RtLibUseGOT", 1); +} + +void Module::setSDKVersion(const VersionTuple &V) { + SmallVector<unsigned, 3> Entries; + Entries.push_back(V.getMajor()); + if (auto Minor = V.getMinor()) { + Entries.push_back(*Minor); + if (auto Subminor = V.getSubminor()) + Entries.push_back(*Subminor); + // Ignore the 'build' component as it can't be represented in the object + // file. + } + addModuleFlag(ModFlagBehavior::Warning, "SDK Version", + ConstantDataArray::get(Context, Entries)); +} + +VersionTuple Module::getSDKVersion() const { + auto *CM = dyn_cast_or_null<ConstantAsMetadata>(getModuleFlag("SDK Version")); + if (!CM) + return {}; + auto *Arr = dyn_cast_or_null<ConstantDataArray>(CM->getValue()); + if (!Arr) + return {}; + auto getVersionComponent = [&](unsigned Index) -> Optional<unsigned> { + if (Index >= Arr->getNumElements()) + return None; + return (unsigned)Arr->getElementAsInteger(Index); + }; + auto Major = getVersionComponent(0); + if (!Major) + return {}; + VersionTuple Result = VersionTuple(*Major); + if (auto Minor = getVersionComponent(1)) { + Result = VersionTuple(*Major, *Minor); + if (auto Subminor = getVersionComponent(2)) { + Result = VersionTuple(*Major, *Minor, *Subminor); + } + } + return Result; +} + +GlobalVariable *llvm::collectUsedGlobalVariables( + const Module &M, SmallPtrSetImpl<GlobalValue *> &Set, bool CompilerUsed) { + const char *Name = CompilerUsed ? "llvm.compiler.used" : "llvm.used"; + GlobalVariable *GV = M.getGlobalVariable(Name); + if (!GV || !GV->hasInitializer()) + return GV; + + const ConstantArray *Init = cast<ConstantArray>(GV->getInitializer()); + for (Value *Op : Init->operands()) { + GlobalValue *G = cast<GlobalValue>(Op->stripPointerCastsNoFollowAliases()); + Set.insert(G); + } + return GV; +} |