1 //===--- TransARCAssign.cpp - Transformations to ARC mode -----------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // makeAssignARCSafe: 10 // 11 // Add '__strong' where appropriate. 12 // 13 // for (id x in collection) { 14 // x = 0; 15 // } 16 // ----> 17 // for (__strong id x in collection) { 18 // x = 0; 19 // } 20 // 21 //===----------------------------------------------------------------------===// 22 23 #include "Transforms.h" 24 #include "Internals.h" 25 #include "clang/AST/ASTContext.h" 26 #include "clang/Sema/SemaDiagnostic.h" 27 28 using namespace clang; 29 using namespace arcmt; 30 using namespace trans; 31 32 namespace { 33 34 class ARCAssignChecker : public RecursiveASTVisitor<ARCAssignChecker> { 35 MigrationPass &Pass; 36 llvm::DenseSet<VarDecl *> ModifiedVars; 37 38 public: ARCAssignChecker(MigrationPass & pass)39 ARCAssignChecker(MigrationPass &pass) : Pass(pass) { } 40 VisitBinaryOperator(BinaryOperator * Exp)41 bool VisitBinaryOperator(BinaryOperator *Exp) { 42 if (Exp->getType()->isDependentType()) 43 return true; 44 45 Expr *E = Exp->getLHS(); 46 SourceLocation OrigLoc = E->getExprLoc(); 47 SourceLocation Loc = OrigLoc; 48 DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts()); 49 if (declRef && isa<VarDecl>(declRef->getDecl())) { 50 ASTContext &Ctx = Pass.Ctx; 51 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(Ctx, &Loc); 52 if (IsLV != Expr::MLV_ConstQualified) 53 return true; 54 VarDecl *var = cast<VarDecl>(declRef->getDecl()); 55 if (var->isARCPseudoStrong()) { 56 Transaction Trans(Pass.TA); 57 if (Pass.TA.clearDiagnostic(diag::err_typecheck_arr_assign_enumeration, 58 Exp->getOperatorLoc())) { 59 if (!ModifiedVars.count(var)) { 60 TypeLoc TLoc = var->getTypeSourceInfo()->getTypeLoc(); 61 Pass.TA.insert(TLoc.getBeginLoc(), "__strong "); 62 ModifiedVars.insert(var); 63 } 64 } 65 } 66 } 67 68 return true; 69 } 70 }; 71 72 } // anonymous namespace 73 makeAssignARCSafe(MigrationPass & pass)74void trans::makeAssignARCSafe(MigrationPass &pass) { 75 ARCAssignChecker assignCheck(pass); 76 assignCheck.TraverseDecl(pass.Ctx.getTranslationUnitDecl()); 77 } 78