forked from OSchip/llvm-project
947 lines
31 KiB
C++
947 lines
31 KiB
C++
//===-- Value.cpp - Implement the Value class -----------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements the Value, ValueHandle, and User classes.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/IR/Value.h"
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#include "LLVMContextImpl.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/SmallString.h"
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#include "llvm/ADT/SetVector.h"
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#include "llvm/IR/Constant.h"
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#include "llvm/IR/Constants.h"
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#include "llvm/IR/DataLayout.h"
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#include "llvm/IR/DerivedTypes.h"
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#include "llvm/IR/DerivedUser.h"
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#include "llvm/IR/GetElementPtrTypeIterator.h"
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#include "llvm/IR/InstrTypes.h"
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#include "llvm/IR/Instructions.h"
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#include "llvm/IR/IntrinsicInst.h"
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#include "llvm/IR/Module.h"
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#include "llvm/IR/Operator.h"
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#include "llvm/IR/Statepoint.h"
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#include "llvm/IR/ValueHandle.h"
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#include "llvm/IR/ValueSymbolTable.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/ErrorHandling.h"
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#include "llvm/Support/ManagedStatic.h"
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#include "llvm/Support/raw_ostream.h"
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#include <algorithm>
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using namespace llvm;
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static cl::opt<unsigned> NonGlobalValueMaxNameSize(
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"non-global-value-max-name-size", cl::Hidden, cl::init(1024),
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cl::desc("Maximum size for the name of non-global values."));
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//===----------------------------------------------------------------------===//
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// Value Class
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//===----------------------------------------------------------------------===//
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static inline Type *checkType(Type *Ty) {
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assert(Ty && "Value defined with a null type: Error!");
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return Ty;
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}
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Value::Value(Type *ty, unsigned scid)
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: VTy(checkType(ty)), UseList(nullptr), SubclassID(scid),
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HasValueHandle(0), SubclassOptionalData(0), SubclassData(0),
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NumUserOperands(0), IsUsedByMD(false), HasName(false) {
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static_assert(ConstantFirstVal == 0, "!(SubclassID < ConstantFirstVal)");
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// FIXME: Why isn't this in the subclass gunk??
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// Note, we cannot call isa<CallInst> before the CallInst has been
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// constructed.
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if (SubclassID == Instruction::Call || SubclassID == Instruction::Invoke ||
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SubclassID == Instruction::CallBr)
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assert((VTy->isFirstClassType() || VTy->isVoidTy() || VTy->isStructTy()) &&
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"invalid CallInst type!");
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else if (SubclassID != BasicBlockVal &&
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(/*SubclassID < ConstantFirstVal ||*/ SubclassID > ConstantLastVal))
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assert((VTy->isFirstClassType() || VTy->isVoidTy()) &&
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"Cannot create non-first-class values except for constants!");
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static_assert(sizeof(Value) == 2 * sizeof(void *) + 2 * sizeof(unsigned),
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"Value too big");
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}
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Value::~Value() {
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// Notify all ValueHandles (if present) that this value is going away.
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if (HasValueHandle)
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ValueHandleBase::ValueIsDeleted(this);
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if (isUsedByMetadata())
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ValueAsMetadata::handleDeletion(this);
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#ifndef NDEBUG // Only in -g mode...
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// Check to make sure that there are no uses of this value that are still
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// around when the value is destroyed. If there are, then we have a dangling
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// reference and something is wrong. This code is here to print out where
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// the value is still being referenced.
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//
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if (!use_empty()) {
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dbgs() << "While deleting: " << *VTy << " %" << getName() << "\n";
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for (auto *U : users())
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dbgs() << "Use still stuck around after Def is destroyed:" << *U << "\n";
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}
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#endif
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assert(use_empty() && "Uses remain when a value is destroyed!");
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// If this value is named, destroy the name. This should not be in a symtab
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// at this point.
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destroyValueName();
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}
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void Value::deleteValue() {
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switch (getValueID()) {
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#define HANDLE_VALUE(Name) \
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case Value::Name##Val: \
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delete static_cast<Name *>(this); \
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break;
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#define HANDLE_MEMORY_VALUE(Name) \
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case Value::Name##Val: \
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static_cast<DerivedUser *>(this)->DeleteValue( \
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static_cast<DerivedUser *>(this)); \
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break;
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#define HANDLE_INSTRUCTION(Name) /* nothing */
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#include "llvm/IR/Value.def"
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#define HANDLE_INST(N, OPC, CLASS) \
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case Value::InstructionVal + Instruction::OPC: \
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delete static_cast<CLASS *>(this); \
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break;
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#define HANDLE_USER_INST(N, OPC, CLASS)
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#include "llvm/IR/Instruction.def"
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default:
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llvm_unreachable("attempting to delete unknown value kind");
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}
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}
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void Value::destroyValueName() {
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ValueName *Name = getValueName();
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if (Name)
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Name->Destroy();
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setValueName(nullptr);
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}
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bool Value::hasNUses(unsigned N) const {
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return hasNItems(use_begin(), use_end(), N);
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}
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bool Value::hasNUsesOrMore(unsigned N) const {
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return hasNItemsOrMore(use_begin(), use_end(), N);
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}
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bool Value::isUsedInBasicBlock(const BasicBlock *BB) const {
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// This can be computed either by scanning the instructions in BB, or by
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// scanning the use list of this Value. Both lists can be very long, but
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// usually one is quite short.
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//
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// Scan both lists simultaneously until one is exhausted. This limits the
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// search to the shorter list.
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BasicBlock::const_iterator BI = BB->begin(), BE = BB->end();
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const_user_iterator UI = user_begin(), UE = user_end();
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for (; BI != BE && UI != UE; ++BI, ++UI) {
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// Scan basic block: Check if this Value is used by the instruction at BI.
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if (is_contained(BI->operands(), this))
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return true;
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// Scan use list: Check if the use at UI is in BB.
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const auto *User = dyn_cast<Instruction>(*UI);
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if (User && User->getParent() == BB)
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return true;
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}
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return false;
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}
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unsigned Value::getNumUses() const {
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return (unsigned)std::distance(use_begin(), use_end());
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}
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static bool getSymTab(Value *V, ValueSymbolTable *&ST) {
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ST = nullptr;
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if (Instruction *I = dyn_cast<Instruction>(V)) {
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if (BasicBlock *P = I->getParent())
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if (Function *PP = P->getParent())
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ST = PP->getValueSymbolTable();
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} else if (BasicBlock *BB = dyn_cast<BasicBlock>(V)) {
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if (Function *P = BB->getParent())
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ST = P->getValueSymbolTable();
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} else if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
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if (Module *P = GV->getParent())
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ST = &P->getValueSymbolTable();
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} else if (Argument *A = dyn_cast<Argument>(V)) {
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if (Function *P = A->getParent())
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ST = P->getValueSymbolTable();
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} else {
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assert(isa<Constant>(V) && "Unknown value type!");
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return true; // no name is setable for this.
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}
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return false;
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}
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ValueName *Value::getValueName() const {
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if (!HasName) return nullptr;
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LLVMContext &Ctx = getContext();
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auto I = Ctx.pImpl->ValueNames.find(this);
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assert(I != Ctx.pImpl->ValueNames.end() &&
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"No name entry found!");
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return I->second;
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}
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void Value::setValueName(ValueName *VN) {
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LLVMContext &Ctx = getContext();
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assert(HasName == Ctx.pImpl->ValueNames.count(this) &&
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"HasName bit out of sync!");
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if (!VN) {
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if (HasName)
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Ctx.pImpl->ValueNames.erase(this);
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HasName = false;
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return;
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}
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HasName = true;
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Ctx.pImpl->ValueNames[this] = VN;
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}
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StringRef Value::getName() const {
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// Make sure the empty string is still a C string. For historical reasons,
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// some clients want to call .data() on the result and expect it to be null
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// terminated.
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if (!hasName())
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return StringRef("", 0);
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return getValueName()->getKey();
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}
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void Value::setNameImpl(const Twine &NewName) {
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// Fast-path: LLVMContext can be set to strip out non-GlobalValue names
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if (getContext().shouldDiscardValueNames() && !isa<GlobalValue>(this))
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return;
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// Fast path for common IRBuilder case of setName("") when there is no name.
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if (NewName.isTriviallyEmpty() && !hasName())
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return;
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SmallString<256> NameData;
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StringRef NameRef = NewName.toStringRef(NameData);
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assert(NameRef.find_first_of(0) == StringRef::npos &&
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"Null bytes are not allowed in names");
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// Name isn't changing?
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if (getName() == NameRef)
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return;
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// Cap the size of non-GlobalValue names.
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if (NameRef.size() > NonGlobalValueMaxNameSize && !isa<GlobalValue>(this))
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NameRef =
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NameRef.substr(0, std::max(1u, (unsigned)NonGlobalValueMaxNameSize));
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assert(!getType()->isVoidTy() && "Cannot assign a name to void values!");
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// Get the symbol table to update for this object.
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ValueSymbolTable *ST;
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if (getSymTab(this, ST))
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return; // Cannot set a name on this value (e.g. constant).
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if (!ST) { // No symbol table to update? Just do the change.
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if (NameRef.empty()) {
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// Free the name for this value.
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destroyValueName();
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return;
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}
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// NOTE: Could optimize for the case the name is shrinking to not deallocate
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// then reallocated.
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destroyValueName();
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// Create the new name.
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setValueName(ValueName::Create(NameRef));
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getValueName()->setValue(this);
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return;
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}
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// NOTE: Could optimize for the case the name is shrinking to not deallocate
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// then reallocated.
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if (hasName()) {
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// Remove old name.
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ST->removeValueName(getValueName());
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destroyValueName();
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if (NameRef.empty())
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return;
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}
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// Name is changing to something new.
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setValueName(ST->createValueName(NameRef, this));
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}
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void Value::setName(const Twine &NewName) {
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setNameImpl(NewName);
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if (Function *F = dyn_cast<Function>(this))
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F->recalculateIntrinsicID();
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}
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void Value::takeName(Value *V) {
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ValueSymbolTable *ST = nullptr;
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// If this value has a name, drop it.
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if (hasName()) {
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// Get the symtab this is in.
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if (getSymTab(this, ST)) {
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// We can't set a name on this value, but we need to clear V's name if
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// it has one.
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if (V->hasName()) V->setName("");
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return; // Cannot set a name on this value (e.g. constant).
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}
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// Remove old name.
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if (ST)
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ST->removeValueName(getValueName());
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destroyValueName();
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}
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// Now we know that this has no name.
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// If V has no name either, we're done.
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if (!V->hasName()) return;
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// Get this's symtab if we didn't before.
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if (!ST) {
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if (getSymTab(this, ST)) {
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// Clear V's name.
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V->setName("");
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return; // Cannot set a name on this value (e.g. constant).
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}
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}
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// Get V's ST, this should always succed, because V has a name.
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ValueSymbolTable *VST;
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bool Failure = getSymTab(V, VST);
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assert(!Failure && "V has a name, so it should have a ST!"); (void)Failure;
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// If these values are both in the same symtab, we can do this very fast.
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// This works even if both values have no symtab yet.
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if (ST == VST) {
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// Take the name!
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setValueName(V->getValueName());
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V->setValueName(nullptr);
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getValueName()->setValue(this);
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return;
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}
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// Otherwise, things are slightly more complex. Remove V's name from VST and
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// then reinsert it into ST.
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if (VST)
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VST->removeValueName(V->getValueName());
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setValueName(V->getValueName());
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V->setValueName(nullptr);
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getValueName()->setValue(this);
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if (ST)
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ST->reinsertValue(this);
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}
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void Value::assertModuleIsMaterializedImpl() const {
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#ifndef NDEBUG
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const GlobalValue *GV = dyn_cast<GlobalValue>(this);
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if (!GV)
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return;
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const Module *M = GV->getParent();
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if (!M)
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return;
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assert(M->isMaterialized());
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#endif
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}
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#ifndef NDEBUG
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static bool contains(SmallPtrSetImpl<ConstantExpr *> &Cache, ConstantExpr *Expr,
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Constant *C) {
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if (!Cache.insert(Expr).second)
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return false;
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for (auto &O : Expr->operands()) {
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if (O == C)
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return true;
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auto *CE = dyn_cast<ConstantExpr>(O);
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if (!CE)
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continue;
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if (contains(Cache, CE, C))
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return true;
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}
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return false;
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}
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static bool contains(Value *Expr, Value *V) {
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if (Expr == V)
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return true;
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auto *C = dyn_cast<Constant>(V);
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if (!C)
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return false;
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auto *CE = dyn_cast<ConstantExpr>(Expr);
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if (!CE)
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return false;
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SmallPtrSet<ConstantExpr *, 4> Cache;
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return contains(Cache, CE, C);
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}
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#endif // NDEBUG
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void Value::doRAUW(Value *New, ReplaceMetadataUses ReplaceMetaUses) {
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assert(New && "Value::replaceAllUsesWith(<null>) is invalid!");
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assert(!contains(New, this) &&
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"this->replaceAllUsesWith(expr(this)) is NOT valid!");
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assert(New->getType() == getType() &&
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"replaceAllUses of value with new value of different type!");
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// Notify all ValueHandles (if present) that this value is going away.
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if (HasValueHandle)
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ValueHandleBase::ValueIsRAUWd(this, New);
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if (ReplaceMetaUses == ReplaceMetadataUses::Yes && isUsedByMetadata())
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ValueAsMetadata::handleRAUW(this, New);
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while (!materialized_use_empty()) {
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Use &U = *UseList;
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// Must handle Constants specially, we cannot call replaceUsesOfWith on a
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// constant because they are uniqued.
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if (auto *C = dyn_cast<Constant>(U.getUser())) {
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if (!isa<GlobalValue>(C)) {
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C->handleOperandChange(this, New);
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continue;
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}
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}
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U.set(New);
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}
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if (BasicBlock *BB = dyn_cast<BasicBlock>(this))
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BB->replaceSuccessorsPhiUsesWith(cast<BasicBlock>(New));
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}
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void Value::replaceAllUsesWith(Value *New) {
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doRAUW(New, ReplaceMetadataUses::Yes);
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}
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void Value::replaceNonMetadataUsesWith(Value *New) {
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doRAUW(New, ReplaceMetadataUses::No);
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}
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// Like replaceAllUsesWith except it does not handle constants or basic blocks.
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// This routine leaves uses within BB.
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void Value::replaceUsesOutsideBlock(Value *New, BasicBlock *BB) {
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assert(New && "Value::replaceUsesOutsideBlock(<null>, BB) is invalid!");
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assert(!contains(New, this) &&
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"this->replaceUsesOutsideBlock(expr(this), BB) is NOT valid!");
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assert(New->getType() == getType() &&
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"replaceUses of value with new value of different type!");
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assert(BB && "Basic block that may contain a use of 'New' must be defined\n");
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use_iterator UI = use_begin(), E = use_end();
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for (; UI != E;) {
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Use &U = *UI;
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++UI;
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auto *Usr = dyn_cast<Instruction>(U.getUser());
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if (Usr && Usr->getParent() == BB)
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continue;
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U.set(New);
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}
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}
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namespace {
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// Various metrics for how much to strip off of pointers.
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enum PointerStripKind {
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PSK_ZeroIndices,
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PSK_ZeroIndicesAndAliases,
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PSK_ZeroIndicesAndAliasesAndInvariantGroups,
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PSK_InBoundsConstantIndices,
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PSK_InBounds
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};
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template <PointerStripKind StripKind>
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static const Value *stripPointerCastsAndOffsets(const Value *V) {
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if (!V->getType()->isPointerTy())
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return V;
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// Even though we don't look through PHI nodes, we could be called on an
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// instruction in an unreachable block, which may be on a cycle.
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SmallPtrSet<const Value *, 4> Visited;
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Visited.insert(V);
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do {
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if (auto *GEP = dyn_cast<GEPOperator>(V)) {
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switch (StripKind) {
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case PSK_ZeroIndicesAndAliases:
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case PSK_ZeroIndicesAndAliasesAndInvariantGroups:
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case PSK_ZeroIndices:
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if (!GEP->hasAllZeroIndices())
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return V;
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break;
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case PSK_InBoundsConstantIndices:
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if (!GEP->hasAllConstantIndices())
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return V;
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LLVM_FALLTHROUGH;
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case PSK_InBounds:
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if (!GEP->isInBounds())
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return V;
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break;
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}
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V = GEP->getPointerOperand();
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} else if (Operator::getOpcode(V) == Instruction::BitCast ||
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Operator::getOpcode(V) == Instruction::AddrSpaceCast) {
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V = cast<Operator>(V)->getOperand(0);
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} else if (auto *GA = dyn_cast<GlobalAlias>(V)) {
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if (StripKind == PSK_ZeroIndices || GA->isInterposable())
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return V;
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V = GA->getAliasee();
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} else {
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if (const auto *Call = dyn_cast<CallBase>(V)) {
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if (const Value *RV = Call->getReturnedArgOperand()) {
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V = RV;
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continue;
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}
|
|
// The result of launder.invariant.group must alias it's argument,
|
|
// but it can't be marked with returned attribute, that's why it needs
|
|
// special case.
|
|
if (StripKind == PSK_ZeroIndicesAndAliasesAndInvariantGroups &&
|
|
(Call->getIntrinsicID() == Intrinsic::launder_invariant_group ||
|
|
Call->getIntrinsicID() == Intrinsic::strip_invariant_group)) {
|
|
V = Call->getArgOperand(0);
|
|
continue;
|
|
}
|
|
}
|
|
return V;
|
|
}
|
|
assert(V->getType()->isPointerTy() && "Unexpected operand type!");
|
|
} while (Visited.insert(V).second);
|
|
|
|
return V;
|
|
}
|
|
} // end anonymous namespace
|
|
|
|
const Value *Value::stripPointerCasts() const {
|
|
return stripPointerCastsAndOffsets<PSK_ZeroIndicesAndAliases>(this);
|
|
}
|
|
|
|
const Value *Value::stripPointerCastsNoFollowAliases() const {
|
|
return stripPointerCastsAndOffsets<PSK_ZeroIndices>(this);
|
|
}
|
|
|
|
const Value *Value::stripInBoundsConstantOffsets() const {
|
|
return stripPointerCastsAndOffsets<PSK_InBoundsConstantIndices>(this);
|
|
}
|
|
|
|
const Value *Value::stripPointerCastsAndInvariantGroups() const {
|
|
return stripPointerCastsAndOffsets<PSK_ZeroIndicesAndAliasesAndInvariantGroups>(
|
|
this);
|
|
}
|
|
|
|
const Value *
|
|
Value::stripAndAccumulateInBoundsConstantOffsets(const DataLayout &DL,
|
|
APInt &Offset) const {
|
|
if (!getType()->isPointerTy())
|
|
return this;
|
|
|
|
assert(Offset.getBitWidth() == DL.getIndexSizeInBits(cast<PointerType>(
|
|
getType())->getAddressSpace()) &&
|
|
"The offset bit width does not match the DL specification.");
|
|
|
|
// Even though we don't look through PHI nodes, we could be called on an
|
|
// instruction in an unreachable block, which may be on a cycle.
|
|
SmallPtrSet<const Value *, 4> Visited;
|
|
Visited.insert(this);
|
|
const Value *V = this;
|
|
do {
|
|
if (auto *GEP = dyn_cast<GEPOperator>(V)) {
|
|
if (!GEP->isInBounds())
|
|
return V;
|
|
APInt GEPOffset(Offset);
|
|
if (!GEP->accumulateConstantOffset(DL, GEPOffset))
|
|
return V;
|
|
Offset = GEPOffset;
|
|
V = GEP->getPointerOperand();
|
|
} else if (Operator::getOpcode(V) == Instruction::BitCast) {
|
|
V = cast<Operator>(V)->getOperand(0);
|
|
} else if (auto *GA = dyn_cast<GlobalAlias>(V)) {
|
|
V = GA->getAliasee();
|
|
} else {
|
|
if (const auto *Call = dyn_cast<CallBase>(V))
|
|
if (const Value *RV = Call->getReturnedArgOperand()) {
|
|
V = RV;
|
|
continue;
|
|
}
|
|
|
|
return V;
|
|
}
|
|
assert(V->getType()->isPointerTy() && "Unexpected operand type!");
|
|
} while (Visited.insert(V).second);
|
|
|
|
return V;
|
|
}
|
|
|
|
const Value *Value::stripInBoundsOffsets() const {
|
|
return stripPointerCastsAndOffsets<PSK_InBounds>(this);
|
|
}
|
|
|
|
uint64_t Value::getPointerDereferenceableBytes(const DataLayout &DL,
|
|
bool &CanBeNull) const {
|
|
assert(getType()->isPointerTy() && "must be pointer");
|
|
|
|
uint64_t DerefBytes = 0;
|
|
CanBeNull = false;
|
|
if (const Argument *A = dyn_cast<Argument>(this)) {
|
|
DerefBytes = A->getDereferenceableBytes();
|
|
if (DerefBytes == 0 && (A->hasByValAttr() || A->hasStructRetAttr())) {
|
|
Type *PT = cast<PointerType>(A->getType())->getElementType();
|
|
if (PT->isSized())
|
|
DerefBytes = DL.getTypeStoreSize(PT);
|
|
}
|
|
if (DerefBytes == 0) {
|
|
DerefBytes = A->getDereferenceableOrNullBytes();
|
|
CanBeNull = true;
|
|
}
|
|
} else if (const auto *Call = dyn_cast<CallBase>(this)) {
|
|
DerefBytes = Call->getDereferenceableBytes(AttributeList::ReturnIndex);
|
|
if (DerefBytes == 0) {
|
|
DerefBytes =
|
|
Call->getDereferenceableOrNullBytes(AttributeList::ReturnIndex);
|
|
CanBeNull = true;
|
|
}
|
|
} else if (const LoadInst *LI = dyn_cast<LoadInst>(this)) {
|
|
if (MDNode *MD = LI->getMetadata(LLVMContext::MD_dereferenceable)) {
|
|
ConstantInt *CI = mdconst::extract<ConstantInt>(MD->getOperand(0));
|
|
DerefBytes = CI->getLimitedValue();
|
|
}
|
|
if (DerefBytes == 0) {
|
|
if (MDNode *MD =
|
|
LI->getMetadata(LLVMContext::MD_dereferenceable_or_null)) {
|
|
ConstantInt *CI = mdconst::extract<ConstantInt>(MD->getOperand(0));
|
|
DerefBytes = CI->getLimitedValue();
|
|
}
|
|
CanBeNull = true;
|
|
}
|
|
} else if (auto *AI = dyn_cast<AllocaInst>(this)) {
|
|
if (!AI->isArrayAllocation()) {
|
|
DerefBytes = DL.getTypeStoreSize(AI->getAllocatedType());
|
|
CanBeNull = false;
|
|
}
|
|
} else if (auto *GV = dyn_cast<GlobalVariable>(this)) {
|
|
if (GV->getValueType()->isSized() && !GV->hasExternalWeakLinkage()) {
|
|
// TODO: Don't outright reject hasExternalWeakLinkage but set the
|
|
// CanBeNull flag.
|
|
DerefBytes = DL.getTypeStoreSize(GV->getValueType());
|
|
CanBeNull = false;
|
|
}
|
|
}
|
|
return DerefBytes;
|
|
}
|
|
|
|
unsigned Value::getPointerAlignment(const DataLayout &DL) const {
|
|
assert(getType()->isPointerTy() && "must be pointer");
|
|
|
|
unsigned Align = 0;
|
|
if (auto *GO = dyn_cast<GlobalObject>(this)) {
|
|
if (isa<Function>(GO)) {
|
|
switch (DL.getFunctionPtrAlignType()) {
|
|
case DataLayout::FunctionPtrAlignType::Independent:
|
|
return DL.getFunctionPtrAlign();
|
|
case DataLayout::FunctionPtrAlignType::MultipleOfFunctionAlign:
|
|
return std::max(DL.getFunctionPtrAlign(), GO->getAlignment());
|
|
}
|
|
}
|
|
Align = GO->getAlignment();
|
|
if (Align == 0) {
|
|
if (auto *GVar = dyn_cast<GlobalVariable>(GO)) {
|
|
Type *ObjectType = GVar->getValueType();
|
|
if (ObjectType->isSized()) {
|
|
// If the object is defined in the current Module, we'll be giving
|
|
// it the preferred alignment. Otherwise, we have to assume that it
|
|
// may only have the minimum ABI alignment.
|
|
if (GVar->isStrongDefinitionForLinker())
|
|
Align = DL.getPreferredAlignment(GVar);
|
|
else
|
|
Align = DL.getABITypeAlignment(ObjectType);
|
|
}
|
|
}
|
|
}
|
|
} else if (const Argument *A = dyn_cast<Argument>(this)) {
|
|
Align = A->getParamAlignment();
|
|
|
|
if (!Align && A->hasStructRetAttr()) {
|
|
// An sret parameter has at least the ABI alignment of the return type.
|
|
Type *EltTy = cast<PointerType>(A->getType())->getElementType();
|
|
if (EltTy->isSized())
|
|
Align = DL.getABITypeAlignment(EltTy);
|
|
}
|
|
} else if (const AllocaInst *AI = dyn_cast<AllocaInst>(this)) {
|
|
Align = AI->getAlignment();
|
|
if (Align == 0) {
|
|
Type *AllocatedType = AI->getAllocatedType();
|
|
if (AllocatedType->isSized())
|
|
Align = DL.getPrefTypeAlignment(AllocatedType);
|
|
}
|
|
} else if (const auto *Call = dyn_cast<CallBase>(this))
|
|
Align = Call->getAttributes().getRetAlignment();
|
|
else if (const LoadInst *LI = dyn_cast<LoadInst>(this))
|
|
if (MDNode *MD = LI->getMetadata(LLVMContext::MD_align)) {
|
|
ConstantInt *CI = mdconst::extract<ConstantInt>(MD->getOperand(0));
|
|
Align = CI->getLimitedValue();
|
|
}
|
|
|
|
return Align;
|
|
}
|
|
|
|
const Value *Value::DoPHITranslation(const BasicBlock *CurBB,
|
|
const BasicBlock *PredBB) const {
|
|
auto *PN = dyn_cast<PHINode>(this);
|
|
if (PN && PN->getParent() == CurBB)
|
|
return PN->getIncomingValueForBlock(PredBB);
|
|
return this;
|
|
}
|
|
|
|
LLVMContext &Value::getContext() const { return VTy->getContext(); }
|
|
|
|
void Value::reverseUseList() {
|
|
if (!UseList || !UseList->Next)
|
|
// No need to reverse 0 or 1 uses.
|
|
return;
|
|
|
|
Use *Head = UseList;
|
|
Use *Current = UseList->Next;
|
|
Head->Next = nullptr;
|
|
while (Current) {
|
|
Use *Next = Current->Next;
|
|
Current->Next = Head;
|
|
Head->setPrev(&Current->Next);
|
|
Head = Current;
|
|
Current = Next;
|
|
}
|
|
UseList = Head;
|
|
Head->setPrev(&UseList);
|
|
}
|
|
|
|
bool Value::isSwiftError() const {
|
|
auto *Arg = dyn_cast<Argument>(this);
|
|
if (Arg)
|
|
return Arg->hasSwiftErrorAttr();
|
|
auto *Alloca = dyn_cast<AllocaInst>(this);
|
|
if (!Alloca)
|
|
return false;
|
|
return Alloca->isSwiftError();
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// ValueHandleBase Class
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void ValueHandleBase::AddToExistingUseList(ValueHandleBase **List) {
|
|
assert(List && "Handle list is null?");
|
|
|
|
// Splice ourselves into the list.
|
|
Next = *List;
|
|
*List = this;
|
|
setPrevPtr(List);
|
|
if (Next) {
|
|
Next->setPrevPtr(&Next);
|
|
assert(getValPtr() == Next->getValPtr() && "Added to wrong list?");
|
|
}
|
|
}
|
|
|
|
void ValueHandleBase::AddToExistingUseListAfter(ValueHandleBase *List) {
|
|
assert(List && "Must insert after existing node");
|
|
|
|
Next = List->Next;
|
|
setPrevPtr(&List->Next);
|
|
List->Next = this;
|
|
if (Next)
|
|
Next->setPrevPtr(&Next);
|
|
}
|
|
|
|
void ValueHandleBase::AddToUseList() {
|
|
assert(getValPtr() && "Null pointer doesn't have a use list!");
|
|
|
|
LLVMContextImpl *pImpl = getValPtr()->getContext().pImpl;
|
|
|
|
if (getValPtr()->HasValueHandle) {
|
|
// If this value already has a ValueHandle, then it must be in the
|
|
// ValueHandles map already.
|
|
ValueHandleBase *&Entry = pImpl->ValueHandles[getValPtr()];
|
|
assert(Entry && "Value doesn't have any handles?");
|
|
AddToExistingUseList(&Entry);
|
|
return;
|
|
}
|
|
|
|
// Ok, it doesn't have any handles yet, so we must insert it into the
|
|
// DenseMap. However, doing this insertion could cause the DenseMap to
|
|
// reallocate itself, which would invalidate all of the PrevP pointers that
|
|
// point into the old table. Handle this by checking for reallocation and
|
|
// updating the stale pointers only if needed.
|
|
DenseMap<Value*, ValueHandleBase*> &Handles = pImpl->ValueHandles;
|
|
const void *OldBucketPtr = Handles.getPointerIntoBucketsArray();
|
|
|
|
ValueHandleBase *&Entry = Handles[getValPtr()];
|
|
assert(!Entry && "Value really did already have handles?");
|
|
AddToExistingUseList(&Entry);
|
|
getValPtr()->HasValueHandle = true;
|
|
|
|
// If reallocation didn't happen or if this was the first insertion, don't
|
|
// walk the table.
|
|
if (Handles.isPointerIntoBucketsArray(OldBucketPtr) ||
|
|
Handles.size() == 1) {
|
|
return;
|
|
}
|
|
|
|
// Okay, reallocation did happen. Fix the Prev Pointers.
|
|
for (DenseMap<Value*, ValueHandleBase*>::iterator I = Handles.begin(),
|
|
E = Handles.end(); I != E; ++I) {
|
|
assert(I->second && I->first == I->second->getValPtr() &&
|
|
"List invariant broken!");
|
|
I->second->setPrevPtr(&I->second);
|
|
}
|
|
}
|
|
|
|
void ValueHandleBase::RemoveFromUseList() {
|
|
assert(getValPtr() && getValPtr()->HasValueHandle &&
|
|
"Pointer doesn't have a use list!");
|
|
|
|
// Unlink this from its use list.
|
|
ValueHandleBase **PrevPtr = getPrevPtr();
|
|
assert(*PrevPtr == this && "List invariant broken");
|
|
|
|
*PrevPtr = Next;
|
|
if (Next) {
|
|
assert(Next->getPrevPtr() == &Next && "List invariant broken");
|
|
Next->setPrevPtr(PrevPtr);
|
|
return;
|
|
}
|
|
|
|
// If the Next pointer was null, then it is possible that this was the last
|
|
// ValueHandle watching VP. If so, delete its entry from the ValueHandles
|
|
// map.
|
|
LLVMContextImpl *pImpl = getValPtr()->getContext().pImpl;
|
|
DenseMap<Value*, ValueHandleBase*> &Handles = pImpl->ValueHandles;
|
|
if (Handles.isPointerIntoBucketsArray(PrevPtr)) {
|
|
Handles.erase(getValPtr());
|
|
getValPtr()->HasValueHandle = false;
|
|
}
|
|
}
|
|
|
|
void ValueHandleBase::ValueIsDeleted(Value *V) {
|
|
assert(V->HasValueHandle && "Should only be called if ValueHandles present");
|
|
|
|
// Get the linked list base, which is guaranteed to exist since the
|
|
// HasValueHandle flag is set.
|
|
LLVMContextImpl *pImpl = V->getContext().pImpl;
|
|
ValueHandleBase *Entry = pImpl->ValueHandles[V];
|
|
assert(Entry && "Value bit set but no entries exist");
|
|
|
|
// We use a local ValueHandleBase as an iterator so that ValueHandles can add
|
|
// and remove themselves from the list without breaking our iteration. This
|
|
// is not really an AssertingVH; we just have to give ValueHandleBase a kind.
|
|
// Note that we deliberately do not the support the case when dropping a value
|
|
// handle results in a new value handle being permanently added to the list
|
|
// (as might occur in theory for CallbackVH's): the new value handle will not
|
|
// be processed and the checking code will mete out righteous punishment if
|
|
// the handle is still present once we have finished processing all the other
|
|
// value handles (it is fine to momentarily add then remove a value handle).
|
|
for (ValueHandleBase Iterator(Assert, *Entry); Entry; Entry = Iterator.Next) {
|
|
Iterator.RemoveFromUseList();
|
|
Iterator.AddToExistingUseListAfter(Entry);
|
|
assert(Entry->Next == &Iterator && "Loop invariant broken.");
|
|
|
|
switch (Entry->getKind()) {
|
|
case Assert:
|
|
break;
|
|
case Weak:
|
|
case WeakTracking:
|
|
// WeakTracking and Weak just go to null, which unlinks them
|
|
// from the list.
|
|
Entry->operator=(nullptr);
|
|
break;
|
|
case Callback:
|
|
// Forward to the subclass's implementation.
|
|
static_cast<CallbackVH*>(Entry)->deleted();
|
|
break;
|
|
}
|
|
}
|
|
|
|
// All callbacks, weak references, and assertingVHs should be dropped by now.
|
|
if (V->HasValueHandle) {
|
|
#ifndef NDEBUG // Only in +Asserts mode...
|
|
dbgs() << "While deleting: " << *V->getType() << " %" << V->getName()
|
|
<< "\n";
|
|
if (pImpl->ValueHandles[V]->getKind() == Assert)
|
|
llvm_unreachable("An asserting value handle still pointed to this"
|
|
" value!");
|
|
|
|
#endif
|
|
llvm_unreachable("All references to V were not removed?");
|
|
}
|
|
}
|
|
|
|
void ValueHandleBase::ValueIsRAUWd(Value *Old, Value *New) {
|
|
assert(Old->HasValueHandle &&"Should only be called if ValueHandles present");
|
|
assert(Old != New && "Changing value into itself!");
|
|
assert(Old->getType() == New->getType() &&
|
|
"replaceAllUses of value with new value of different type!");
|
|
|
|
// Get the linked list base, which is guaranteed to exist since the
|
|
// HasValueHandle flag is set.
|
|
LLVMContextImpl *pImpl = Old->getContext().pImpl;
|
|
ValueHandleBase *Entry = pImpl->ValueHandles[Old];
|
|
|
|
assert(Entry && "Value bit set but no entries exist");
|
|
|
|
// We use a local ValueHandleBase as an iterator so that
|
|
// ValueHandles can add and remove themselves from the list without
|
|
// breaking our iteration. This is not really an AssertingVH; we
|
|
// just have to give ValueHandleBase some kind.
|
|
for (ValueHandleBase Iterator(Assert, *Entry); Entry; Entry = Iterator.Next) {
|
|
Iterator.RemoveFromUseList();
|
|
Iterator.AddToExistingUseListAfter(Entry);
|
|
assert(Entry->Next == &Iterator && "Loop invariant broken.");
|
|
|
|
switch (Entry->getKind()) {
|
|
case Assert:
|
|
case Weak:
|
|
// Asserting and Weak handles do not follow RAUW implicitly.
|
|
break;
|
|
case WeakTracking:
|
|
// Weak goes to the new value, which will unlink it from Old's list.
|
|
Entry->operator=(New);
|
|
break;
|
|
case Callback:
|
|
// Forward to the subclass's implementation.
|
|
static_cast<CallbackVH*>(Entry)->allUsesReplacedWith(New);
|
|
break;
|
|
}
|
|
}
|
|
|
|
#ifndef NDEBUG
|
|
// If any new weak value handles were added while processing the
|
|
// list, then complain about it now.
|
|
if (Old->HasValueHandle)
|
|
for (Entry = pImpl->ValueHandles[Old]; Entry; Entry = Entry->Next)
|
|
switch (Entry->getKind()) {
|
|
case WeakTracking:
|
|
dbgs() << "After RAUW from " << *Old->getType() << " %"
|
|
<< Old->getName() << " to " << *New->getType() << " %"
|
|
<< New->getName() << "\n";
|
|
llvm_unreachable(
|
|
"A weak tracking value handle still pointed to the old value!\n");
|
|
default:
|
|
break;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
// Pin the vtable to this file.
|
|
void CallbackVH::anchor() {}
|