================ @@ -0,0 +1,352 @@ +//===----------------------------------------------------------------------===// +// +// 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 "StaticInitializationCycleCheck.h" +#include "clang/AST/ASTContext.h" +#include "clang/AST/DynamicRecursiveASTVisitor.h" +#include "clang/ASTMatchers/ASTMatchFinder.h" +#include "clang/Analysis/CallGraph.h" +#include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/SCCIterator.h" + +using namespace clang; +using namespace clang::ast_matchers; + +namespace { + +// Compute (for the purpose of this check) if the value of a DeclRefExpr is used +// (at runtime). +// The value is not used if it appears at LHS of an assignment or it appears +// inside a compile-time constant expression (like 'sizeof'). +bool isUnusedValue(const DeclRefExpr *DRE, ASTContext &ACtx) { + ParentMapContext &PMC = ACtx.getParentMapContext(); + DynTypedNodeList Parents = PMC.getParents(*DRE); + const BinaryOperator *ParentBO = nullptr; + while (!Parents.empty()) { + if (const Expr *E = Parents[0].get<Expr>()) { + if (E->isIntegerConstantExpr(ACtx)) + return true; + if ((ParentBO = dyn_cast<BinaryOperator>(E))) + break; + } + Parents = PMC.getParents(Parents[0]); + } + if (!ParentBO) + return false; + return ParentBO->isAssignmentOp() && + ParentBO->getLHS()->IgnoreParenCasts() == DRE; +} + +class VarUseNode; + +// Store the reference to a variable or the call location of a function. +// 'Ref' is a DeclRefExpr or a CallExpr. +// 'Node' contains information about corresponding VarDecl or FunctionDecl. +struct VarUseRecord { + const Expr *Ref; + VarUseNode *Node; + + VarUseRecord() = default; + VarUseRecord(const Expr *Ref, VarUseNode *N) : Ref(Ref), Node(N) {} + operator VarUseNode *() const { return Node; } +}; + +// One node in the variable usage graph. +// If 'D' is a VarDecl: +// 'Uses' contains all static variables and global function calls in the +// initializer expression. +// If 'D' is a FunctionDecl: +// 'Uses' contains all static variable references and global function calls in +// the function body. +class VarUseNode { + const NamedDecl *D; + llvm::SmallVector<VarUseRecord, 2> Uses; + +public: + VarUseNode(const NamedDecl *D) : D(D) {} + + const NamedDecl *getDecl() const { return D; } + bool isVar() const { return isa<VarDecl>(D); } + bool isFunction() const { return isa<FunctionDecl>(D); } + const VarDecl *getVar() const { return cast<VarDecl>(D); } + const FunctionDecl *getFunction() const { return cast<FunctionDecl>(D); } + + using const_iterator = llvm::SmallVectorImpl<VarUseRecord>::const_iterator; + + const_iterator begin() const { return Uses.begin(); } + const_iterator end() const { return Uses.end(); } + + llvm::iterator_range<const_iterator> uses() const { + return llvm::make_range(begin(), end()); + } + + bool empty() const { return Uses.empty(); } + unsigned size() const { return Uses.size(); } + + friend class VarUseCollector; + friend class VarUseGraphBuilder; + friend class VarUseGraph; +}; + +inline bool operator==(const VarUseRecord &LHS, const VarUseNode *RHS) { + return LHS.Node == RHS; +} ---------------- balazske wrote:
This operator was not used, it is removed now. https://github.com/llvm/llvm-project/pull/175342 _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
