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//===--- CFGStmtVisitor.h - Visitor for Stmts in a CFG ----------*- C++ -*-===//
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// The LLVM Compiler Infrastructure
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//===----------------------------------------------------------------------===//
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// This file defines the CFGStmtVisitor interface, which extends
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// StmtVisitor. This interface is useful for visiting statements in a CFG
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// where some statements have implicit control-flow and thus should
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// be treated specially.
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_CLANG_ANALYSIS_CFGSTMTVISITOR_H
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#define LLVM_CLANG_ANALYSIS_CFGSTMTVISITOR_H
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#include "clang/AST/StmtVisitor.h"
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#include "clang/Analysis/CFG.h"
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#define DISPATCH_CASE(CLASS) \
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case Stmt::CLASS ## Class: return \
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static_cast<ImplClass*>(this)->BlockStmt_Visit ## CLASS(static_cast<CLASS*>(S));
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#define DEFAULT_BLOCKSTMT_VISIT(CLASS) RetTy BlockStmt_Visit ## CLASS(CLASS *S)\
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static_cast<ImplClass*>(this)->BlockStmt_VisitImplicitControlFlowExpr(\
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template <typename ImplClass, typename RetTy=void>
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class CFGStmtVisitor : public StmtVisitor<ImplClass,RetTy> {
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NullifyStmt(Stmt*& s) : S(s) {}
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~NullifyStmt() { S = NULL; }
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CFGStmtVisitor() : CurrentBlkStmt(NULL) {}
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Stmt *getCurrentBlkStmt() const { return CurrentBlkStmt; }
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RetTy Visit(Stmt *S) {
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if (S == CurrentBlkStmt ||
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!static_cast<ImplClass*>(this)->getCFG().isBlkExpr(S))
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return StmtVisitor<ImplClass,RetTy>::Visit(S);
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/// VisitConditionVariableInit - Handle the initialization of condition
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/// variables at branches. Valid statements include IfStmt, ForStmt,
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/// WhileStmt, and SwitchStmt.
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RetTy VisitConditionVariableInit(Stmt *S) {
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/// BlockVisit_XXX - Visitor methods for visiting the "root" statements in
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/// CFGBlocks. Root statements are the statements that appear explicitly in
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/// the list of statements in a CFGBlock. For substatements, or when there
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/// is no implementation provided for a BlockStmt_XXX method, we default
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/// to using StmtVisitor's Visit method.
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RetTy BlockStmt_Visit(Stmt *S) {
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NullifyStmt cleanup(CurrentBlkStmt);
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switch (S->getStmtClass()) {
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case Stmt::IfStmtClass:
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case Stmt::ForStmtClass:
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case Stmt::WhileStmtClass:
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case Stmt::SwitchStmtClass:
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return static_cast<ImplClass*>(this)->VisitConditionVariableInit(S);
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DISPATCH_CASE(StmtExpr)
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DISPATCH_CASE(ConditionalOperator)
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DISPATCH_CASE(BinaryConditionalOperator)
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DISPATCH_CASE(ObjCForCollectionStmt)
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DISPATCH_CASE(CXXForRangeStmt)
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case Stmt::BinaryOperatorClass: {
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BinaryOperator* B = cast<BinaryOperator>(S);
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return static_cast<ImplClass*>(this)->BlockStmt_VisitLogicalOp(B);
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else if (B->getOpcode() == BO_Comma)
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return static_cast<ImplClass*>(this)->BlockStmt_VisitComma(B);
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static_cast<ImplClass*>(this)->BlockStmt_VisitExpr(cast<Expr>(S));
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return static_cast<ImplClass*>(this)->BlockStmt_VisitStmt(S);
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DEFAULT_BLOCKSTMT_VISIT(StmtExpr)
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DEFAULT_BLOCKSTMT_VISIT(ConditionalOperator)
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DEFAULT_BLOCKSTMT_VISIT(BinaryConditionalOperator)
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RetTy BlockStmt_VisitObjCForCollectionStmt(ObjCForCollectionStmt *S) {
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return static_cast<ImplClass*>(this)->BlockStmt_VisitStmt(S);
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RetTy BlockStmt_VisitCXXForRangeStmt(CXXForRangeStmt *S) {
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return static_cast<ImplClass*>(this)->BlockStmt_VisitStmt(S);
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RetTy BlockStmt_VisitImplicitControlFlowExpr(Expr *E) {
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return static_cast<ImplClass*>(this)->BlockStmt_VisitExpr(E);
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RetTy BlockStmt_VisitExpr(Expr *E) {
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return static_cast<ImplClass*>(this)->BlockStmt_VisitStmt(E);
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RetTy BlockStmt_VisitStmt(Stmt *S) {
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return static_cast<ImplClass*>(this)->Visit(S);
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RetTy BlockStmt_VisitLogicalOp(BinaryOperator* B) {
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static_cast<ImplClass*>(this)->BlockStmt_VisitImplicitControlFlowExpr(B);
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RetTy BlockStmt_VisitComma(BinaryOperator* B) {
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static_cast<ImplClass*>(this)->BlockStmt_VisitImplicitControlFlowExpr(B);
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//===--------------------------------------------------------------------===//
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// Utility methods. Not called by default (but subclasses may use them).
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//===--------------------------------------------------------------------===//
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/// VisitChildren: Call "Visit" on each child of S.
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void VisitChildren(Stmt *S) {
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switch (S->getStmtClass()) {
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case Stmt::StmtExprClass: {
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CompoundStmt *CS = cast<StmtExpr>(S)->getSubStmt();
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if (CS->body_empty()) return;
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static_cast<ImplClass*>(this)->Visit(CS->body_back());
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case Stmt::BinaryOperatorClass: {
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BinaryOperator* B = cast<BinaryOperator>(S);
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if (B->getOpcode() != BO_Comma) break;
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static_cast<ImplClass*>(this)->Visit(B->getRHS());
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for (Stmt::child_range I = S->children(); I; ++I)
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if (*I) static_cast<ImplClass*>(this)->Visit(*I);
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#undef DEFAULT_BLOCKSTMT_VISIT
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} // end namespace clang