| //===--- ParentMap.cpp - Mappings from Stmts to their Parents ---*- C++ -*-===// |
| // |
| // 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 defines the ParentMap class. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/AST/ParentMap.h" |
| #include "clang/AST/Decl.h" |
| #include "clang/AST/Expr.h" |
| #include "clang/AST/ExprCXX.h" |
| #include "clang/AST/StmtObjC.h" |
| #include "llvm/ADT/DenseMap.h" |
| |
| using namespace clang; |
| |
| typedef llvm::DenseMap<Stmt*, Stmt*> MapTy; |
| |
| enum OpaqueValueMode { |
| OV_Transparent, |
| OV_Opaque |
| }; |
| |
| static void BuildParentMap(MapTy& M, Stmt* S, |
| OpaqueValueMode OVMode = OV_Transparent) { |
| if (!S) |
| return; |
| |
| switch (S->getStmtClass()) { |
| case Stmt::PseudoObjectExprClass: { |
| assert(OVMode == OV_Transparent && "Should not appear alongside OVEs"); |
| PseudoObjectExpr *POE = cast<PseudoObjectExpr>(S); |
| |
| // If we are rebuilding the map, clear out any existing state. |
| if (M[POE->getSyntacticForm()]) |
| for (Stmt *SubStmt : S->children()) |
| M[SubStmt] = nullptr; |
| |
| M[POE->getSyntacticForm()] = S; |
| BuildParentMap(M, POE->getSyntacticForm(), OV_Transparent); |
| |
| for (PseudoObjectExpr::semantics_iterator I = POE->semantics_begin(), |
| E = POE->semantics_end(); |
| I != E; ++I) { |
| M[*I] = S; |
| BuildParentMap(M, *I, OV_Opaque); |
| } |
| break; |
| } |
| case Stmt::BinaryConditionalOperatorClass: { |
| assert(OVMode == OV_Transparent && "Should not appear alongside OVEs"); |
| BinaryConditionalOperator *BCO = cast<BinaryConditionalOperator>(S); |
| |
| M[BCO->getCommon()] = S; |
| BuildParentMap(M, BCO->getCommon(), OV_Transparent); |
| |
| M[BCO->getCond()] = S; |
| BuildParentMap(M, BCO->getCond(), OV_Opaque); |
| |
| M[BCO->getTrueExpr()] = S; |
| BuildParentMap(M, BCO->getTrueExpr(), OV_Opaque); |
| |
| M[BCO->getFalseExpr()] = S; |
| BuildParentMap(M, BCO->getFalseExpr(), OV_Transparent); |
| |
| break; |
| } |
| case Stmt::OpaqueValueExprClass: { |
| // FIXME: This isn't correct; it assumes that multiple OpaqueValueExprs |
| // share a single source expression, but in the AST a single |
| // OpaqueValueExpr is shared among multiple parent expressions. |
| // The right thing to do is to give the OpaqueValueExpr its syntactic |
| // parent, then not reassign that when traversing the semantic expressions. |
| OpaqueValueExpr *OVE = cast<OpaqueValueExpr>(S); |
| if (OVMode == OV_Transparent || !M[OVE->getSourceExpr()]) { |
| M[OVE->getSourceExpr()] = S; |
| BuildParentMap(M, OVE->getSourceExpr(), OV_Transparent); |
| } |
| break; |
| } |
| case Stmt::CapturedStmtClass: |
| for (Stmt *SubStmt : S->children()) { |
| if (SubStmt) { |
| M[SubStmt] = S; |
| BuildParentMap(M, SubStmt, OVMode); |
| } |
| } |
| if (Stmt *SubStmt = cast<CapturedStmt>(S)->getCapturedStmt()) { |
| M[SubStmt] = S; |
| BuildParentMap(M, SubStmt, OVMode); |
| } |
| break; |
| default: |
| for (Stmt *SubStmt : S->children()) { |
| if (SubStmt) { |
| M[SubStmt] = S; |
| BuildParentMap(M, SubStmt, OVMode); |
| } |
| } |
| break; |
| } |
| } |
| |
| ParentMap::ParentMap(Stmt *S) : Impl(nullptr) { |
| if (S) { |
| MapTy *M = new MapTy(); |
| BuildParentMap(*M, S); |
| Impl = M; |
| } |
| } |
| |
| ParentMap::~ParentMap() { |
| delete (MapTy*) Impl; |
| } |
| |
| void ParentMap::addStmt(Stmt* S) { |
| if (S) { |
| BuildParentMap(*(MapTy*) Impl, S); |
| } |
| } |
| |
| void ParentMap::setParent(const Stmt *S, const Stmt *Parent) { |
| assert(S); |
| assert(Parent); |
| MapTy *M = reinterpret_cast<MapTy *>(Impl); |
| M->insert(std::make_pair(const_cast<Stmt *>(S), const_cast<Stmt *>(Parent))); |
| } |
| |
| Stmt* ParentMap::getParent(Stmt* S) const { |
| MapTy* M = (MapTy*) Impl; |
| MapTy::iterator I = M->find(S); |
| return I == M->end() ? nullptr : I->second; |
| } |
| |
| Stmt *ParentMap::getParentIgnoreParens(Stmt *S) const { |
| do { S = getParent(S); } while (S && isa<ParenExpr>(S)); |
| return S; |
| } |
| |
| Stmt *ParentMap::getParentIgnoreParenCasts(Stmt *S) const { |
| do { |
| S = getParent(S); |
| } |
| while (S && (isa<ParenExpr>(S) || isa<CastExpr>(S))); |
| |
| return S; |
| } |
| |
| Stmt *ParentMap::getParentIgnoreParenImpCasts(Stmt *S) const { |
| do { |
| S = getParent(S); |
| } while (S && isa<Expr>(S) && cast<Expr>(S)->IgnoreParenImpCasts() != S); |
| |
| return S; |
| } |
| |
| Stmt *ParentMap::getOuterParenParent(Stmt *S) const { |
| Stmt *Paren = nullptr; |
| while (isa<ParenExpr>(S)) { |
| Paren = S; |
| S = getParent(S); |
| }; |
| return Paren; |
| } |
| |
| bool ParentMap::isConsumedExpr(Expr* E) const { |
| Stmt *P = getParent(E); |
| Stmt *DirectChild = E; |
| |
| // Ignore parents that don't guarantee consumption. |
| while (P && (isa<ParenExpr>(P) || isa<CastExpr>(P) || |
| isa<FullExpr>(P))) { |
| DirectChild = P; |
| P = getParent(P); |
| } |
| |
| if (!P) |
| return false; |
| |
| switch (P->getStmtClass()) { |
| default: |
| return isa<Expr>(P); |
| case Stmt::DeclStmtClass: |
| return true; |
| case Stmt::BinaryOperatorClass: { |
| BinaryOperator *BE = cast<BinaryOperator>(P); |
| // If it is a comma, only the right side is consumed. |
| // If it isn't a comma, both sides are consumed. |
| return BE->getOpcode()!=BO_Comma ||DirectChild==BE->getRHS(); |
| } |
| case Stmt::ForStmtClass: |
| return DirectChild == cast<ForStmt>(P)->getCond(); |
| case Stmt::WhileStmtClass: |
| return DirectChild == cast<WhileStmt>(P)->getCond(); |
| case Stmt::DoStmtClass: |
| return DirectChild == cast<DoStmt>(P)->getCond(); |
| case Stmt::IfStmtClass: |
| return DirectChild == cast<IfStmt>(P)->getCond(); |
| case Stmt::IndirectGotoStmtClass: |
| return DirectChild == cast<IndirectGotoStmt>(P)->getTarget(); |
| case Stmt::SwitchStmtClass: |
| return DirectChild == cast<SwitchStmt>(P)->getCond(); |
| case Stmt::ObjCForCollectionStmtClass: |
| return DirectChild == cast<ObjCForCollectionStmt>(P)->getCollection(); |
| case Stmt::ReturnStmtClass: |
| return true; |
| } |
| } |
| |