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Diffstat (limited to 'clang/lib/ARCMigrate/Transforms.cpp')
-rw-r--r-- | clang/lib/ARCMigrate/Transforms.cpp | 2094 |
1 files changed, 2094 insertions, 0 deletions
diff --git a/clang/lib/ARCMigrate/Transforms.cpp b/clang/lib/ARCMigrate/Transforms.cpp new file mode 100644 index 00000000000..ab3bc1dbe7a --- /dev/null +++ b/clang/lib/ARCMigrate/Transforms.cpp @@ -0,0 +1,2094 @@ +//===--- Tranforms.cpp - Tranformations to ARC mode -----------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// Transformations: +//===----------------------------------------------------------------------===// +// +// castNonObjCToObjC: +// +// A cast of non-objc pointer to an objc one is checked. If the non-objc pointer +// is from a file-level variable, objc_unretainedObject function is used to +// convert it. +// +// NSString *str = (NSString *)kUTTypePlainText; +// str = b ? kUTTypeRTF : kUTTypePlainText; +// ----> +// NSString *str = objc_unretainedObject(kUTTypePlainText); +// str = objc_unretainedObject(b ? kUTTypeRTF : kUTTypePlainText); +// +// For a C pointer to ObjC, objc_unretainedPointer is used. +// +// void *vp = str; // NSString* +// ----> +// void *vp = (void*)objc_unretainedPointer(str); +// +//===----------------------------------------------------------------------===// +// +// rewriteAllocCopyWithZone: +// +// Calls to +allocWithZone/-copyWithZone/-mutableCopyWithZone are changed to +// +alloc/-copy/-mutableCopy if we can safely remove the given parameter. +// +// Foo *foo1 = [[Foo allocWithZone:[self zone]] init]; +// ----> +// Foo *foo1 = [[Foo alloc] init]; +// +//===----------------------------------------------------------------------===// +// +// rewriteAutoreleasePool: +// +// Calls to NSAutoreleasePools will be rewritten as an @autorelease scope. +// +// NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; +// ... +// [pool release]; +// ----> +// @autorelease { +// ... +// } +// +// An NSAutoreleasePool will not be touched if: +// - There is not a corresponding -release/-drain in the same scope +// - Not all references of the NSAutoreleasePool variable can be removed +// - There is a variable that is declared inside the intended @autorelease scope +// which is also used outside it. +// +//===----------------------------------------------------------------------===// +// +// makeAssignARCSafe: +// +// Add '__strong' where appropriate. +// +// for (id x in collection) { +// x = 0; +// } +// ----> +// for (__strong id x in collection) { +// x = 0; +// } +// +//===----------------------------------------------------------------------===// +// +// removeRetainReleaseDealloc: +// +// Removes retain/release/autorelease/dealloc messages. +// +// return [[foo retain] autorelease]; +// ----> +// return foo; +// +//===----------------------------------------------------------------------===// +// +// removeEmptyStatements: +// +// Removes empty statements that are leftovers from previous transformations. +// e.g for +// +// [x retain]; +// +// removeRetainReleaseDealloc will leave an empty ";" that removeEmptyStatements +// will remove. +// +//===----------------------------------------------------------------------===// +// +// changeIvarsOfAssignProperties: +// +// If a property is synthesized with 'assign' attribute and the user didn't +// set a lifetime attribute, change the property to 'weak' or add +// __unsafe_unretained if the ARC runtime is not available. +// +// @interface Foo : NSObject { +// NSObject *x; +// } +// @property (assign) id x; +// @end +// ----> +// @interface Foo : NSObject { +// NSObject *__weak x; +// } +// @property (weak) id x; +// @end +// +//===----------------------------------------------------------------------===// +// +// rewriteUnusedDelegateInit: +// +// Rewrites an unused result of calling a delegate initialization, to assigning +// the result to self. +// e.g +// [self init]; +// ----> +// self = [self init]; +// +//===----------------------------------------------------------------------===// +// +// rewriteBlockObjCVariable: +// +// Adding __block to an obj-c variable could be either because the the variable +// is used for output storage or the user wanted to break a retain cycle. +// This transformation checks whether a reference of the variable for the block +// is actually needed (it is assigned to or its address is taken) or not. +// If the reference is not needed it will assume __block was added to break a +// cycle so it will remove '__block' and add __weak/__unsafe_unretained. +// e.g +// +// __block Foo *x; +// bar(^ { [x cake]; }); +// ----> +// __weak Foo *x; +// bar(^ { [x cake]; }); +// +//===----------------------------------------------------------------------===// +// +// removeZeroOutIvarsInDealloc: +// +// Removes zero'ing out "strong" @synthesized properties in a -dealloc method. +// +//===----------------------------------------------------------------------===// + +#include "Internals.h" +#include "clang/Sema/SemaDiagnostic.h" +#include "clang/AST/RecursiveASTVisitor.h" +#include "clang/AST/StmtVisitor.h" +#include "clang/AST/ParentMap.h" +#include "clang/Analysis/DomainSpecific/CocoaConventions.h" +#include "clang/Lex/Lexer.h" +#include "clang/Basic/SourceManager.h" +#include "llvm/ADT/StringSwitch.h" +#include "llvm/ADT/DenseSet.h" +#include <map> + +using namespace clang; +using namespace arcmt; +using llvm::StringRef; + +//===----------------------------------------------------------------------===// +// Transformations. +//===----------------------------------------------------------------------===// + +namespace { + +class RemovablesCollector : public RecursiveASTVisitor<RemovablesCollector> { + llvm::DenseSet<Expr *> &Removables; + +public: + RemovablesCollector(llvm::DenseSet<Expr *> &removables) + : Removables(removables) { } + + bool shouldWalkTypesOfTypeLocs() const { return false; } + + bool TraverseStmtExpr(StmtExpr *E) { + CompoundStmt *S = E->getSubStmt(); + for (CompoundStmt::body_iterator + I = S->body_begin(), E = S->body_end(); I != E; ++I) { + if (I != E - 1) + mark(*I); + TraverseStmt(*I); + } + return true; + } + + bool VisitCompoundStmt(CompoundStmt *S) { + for (CompoundStmt::body_iterator + I = S->body_begin(), E = S->body_end(); I != E; ++I) + mark(*I); + return true; + } + + bool VisitIfStmt(IfStmt *S) { + mark(S->getThen()); + mark(S->getElse()); + return true; + } + + bool VisitWhileStmt(WhileStmt *S) { + mark(S->getBody()); + return true; + } + + bool VisitDoStmt(DoStmt *S) { + mark(S->getBody()); + return true; + } + + bool VisitForStmt(ForStmt *S) { + mark(S->getInit()); + mark(S->getInc()); + mark(S->getBody()); + return true; + } + +private: + void mark(Stmt *S) { + if (!S) return; + + if (LabelStmt *Label = dyn_cast<LabelStmt>(S)) + return mark(Label->getSubStmt()); + if (ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(S)) + return mark(CE->getSubExpr()); + if (ExprWithCleanups *EWC = dyn_cast<ExprWithCleanups>(S)) + return mark(EWC->getSubExpr()); + if (Expr *E = dyn_cast<Expr>(S)) + Removables.insert(E); + } +}; + +} // end anonymous namespace. + +static bool HasSideEffects(Expr *E, ASTContext &Ctx) { + if (!E || !E->HasSideEffects(Ctx)) + return false; + + E = E->IgnoreParenCasts(); + ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E); + if (!ME) + return true; + switch (ME->getMethodFamily()) { + case OMF_autorelease: + case OMF_dealloc: + case OMF_release: + case OMF_retain: + switch (ME->getReceiverKind()) { + case ObjCMessageExpr::SuperInstance: + return false; + case ObjCMessageExpr::Instance: + return HasSideEffects(ME->getInstanceReceiver(), Ctx); + default: + break; + } + break; + default: + break; + } + + return true; +} + +static void removeDeallocMethod(MigrationPass &pass) { + ASTContext &Ctx = pass.Ctx; + TransformActions &TA = pass.TA; + DeclContext *DC = Ctx.getTranslationUnitDecl(); + ObjCMethodDecl *DeallocMethodDecl = 0; + IdentifierInfo *II = &Ctx.Idents.get("dealloc"); + + for (DeclContext::decl_iterator I = DC->decls_begin(), E = DC->decls_end(); + I != E; ++I) { + Decl *D = *I; + if (ObjCImplementationDecl *IMD = + dyn_cast<ObjCImplementationDecl>(D)) { + DeallocMethodDecl = 0; + for (ObjCImplementationDecl::instmeth_iterator I = + IMD->instmeth_begin(), E = IMD->instmeth_end(); + I != E; ++I) { + ObjCMethodDecl *OMD = *I; + if (OMD->isInstanceMethod() && + OMD->getSelector() == Ctx.Selectors.getSelector(0, &II)) { + DeallocMethodDecl = OMD; + break; + } + } + if (DeallocMethodDecl && + DeallocMethodDecl->getCompoundBody()->body_empty()) { + Transaction Trans(TA); + TA.remove(DeallocMethodDecl->getSourceRange()); + } + } + } +} + +namespace { + +class ReferenceClear : public RecursiveASTVisitor<ReferenceClear> { + llvm::DenseSet<Expr *> &Refs; +public: + ReferenceClear(llvm::DenseSet<Expr *> &refs) : Refs(refs) { } + bool VisitDeclRefExpr(DeclRefExpr *E) { Refs.erase(E); return true; } + bool VisitBlockDeclRefExpr(BlockDeclRefExpr *E) { Refs.erase(E); return true; } + void clearRefsIn(Stmt *S) { TraverseStmt(S); } + template <typename iterator> + void clearRefsIn(iterator begin, iterator end) { + for (; begin != end; ++begin) + TraverseStmt(*begin); + } +}; + +class ReferenceCollector : public RecursiveASTVisitor<ReferenceCollector> { + ValueDecl *Dcl; + llvm::DenseSet<Expr *> &Refs; + +public: + ReferenceCollector(llvm::DenseSet<Expr *> &refs) + : Dcl(0), Refs(refs) { } + + void lookFor(ValueDecl *D, Stmt *S) { + Dcl = D; + TraverseStmt(S); + } + + bool VisitDeclRefExpr(DeclRefExpr *E) { + if (E->getDecl() == Dcl) + Refs.insert(E); + return true; + } + + bool VisitBlockDeclRefExpr(BlockDeclRefExpr *E) { + if (E->getDecl() == Dcl) + Refs.insert(E); + return true; + } +}; + +class ReleaseCollector : public RecursiveASTVisitor<ReleaseCollector> { + Decl *Dcl; + llvm::SmallVectorImpl<ObjCMessageExpr *> &Releases; + +public: + ReleaseCollector(Decl *D, llvm::SmallVectorImpl<ObjCMessageExpr *> &releases) + : Dcl(D), Releases(releases) { } + + bool VisitObjCMessageExpr(ObjCMessageExpr *E) { + if (!E->isInstanceMessage()) + return true; + if (E->getMethodFamily() != OMF_release) + return true; + Expr *instance = E->getInstanceReceiver()->IgnoreParenCasts(); + if (DeclRefExpr *DE = dyn_cast<DeclRefExpr>(instance)) { + if (DE->getDecl() == Dcl) + Releases.push_back(E); + } + return true; + } +}; + +template <typename BODY_TRANS> +class BodyTransform : public RecursiveASTVisitor<BodyTransform<BODY_TRANS> > { + MigrationPass &Pass; + +public: + BodyTransform(MigrationPass &pass) : Pass(pass) { } + + void handleBody(Decl *D) { + Stmt *body = D->getBody(); + if (body) { + BODY_TRANS(D, Pass).transformBody(body); + } + } + + bool TraverseBlockDecl(BlockDecl *D) { + handleBody(D); + return true; + } + bool TraverseObjCMethodDecl(ObjCMethodDecl *D) { + if (D->isThisDeclarationADefinition()) + handleBody(D); + return true; + } + bool TraverseFunctionDecl(FunctionDecl *D) { + if (D->isThisDeclarationADefinition()) + handleBody(D); + return true; + } +}; + +} // anonymous namespace + +//===----------------------------------------------------------------------===// +// makeAssignARCSafe +//===----------------------------------------------------------------------===// + +namespace { + +class ARCAssignChecker : public RecursiveASTVisitor<ARCAssignChecker> { + MigrationPass &Pass; + llvm::DenseSet<VarDecl *> ModifiedVars; + +public: + ARCAssignChecker(MigrationPass &pass) : Pass(pass) { } + + bool VisitBinaryOperator(BinaryOperator *Exp) { + Expr *E = Exp->getLHS(); + SourceLocation OrigLoc = E->getExprLoc(); + SourceLocation Loc = OrigLoc; + DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts()); + if (declRef && isa<VarDecl>(declRef->getDecl())) { + ASTContext &Ctx = Pass.Ctx; + Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(Ctx, &Loc); + if (IsLV != Expr::MLV_ConstQualified) + return true; + VarDecl *var = cast<VarDecl>(declRef->getDecl()); + if (var->getType().getLocalQualifiers().getObjCLifetime() + == Qualifiers::OCL_ExplicitNone && + (var->getTypeSourceInfo() && + !var->getTypeSourceInfo()->getType().isConstQualified())) { + Transaction Trans(Pass.TA); + if (Pass.TA.clearDiagnostic(diag::err_typecheck_arr_assign_enumeration, + Exp->getOperatorLoc())) { + if (!ModifiedVars.count(var)) { + TypeLoc TLoc = var->getTypeSourceInfo()->getTypeLoc(); + Pass.TA.insert(TLoc.getBeginLoc(), "__strong "); + ModifiedVars.insert(var); + } + } + } + } + + return true; + } +}; + +} // anonymous namespace + +static void makeAssignARCSafe(MigrationPass &pass) { + ARCAssignChecker assignCheck(pass); + assignCheck.TraverseDecl(pass.Ctx.getTranslationUnitDecl()); +} + +//===----------------------------------------------------------------------===// +// castNonObjCToObjC +//===----------------------------------------------------------------------===// + +namespace { + +class NonObjCToObjCCaster : public RecursiveASTVisitor<NonObjCToObjCCaster> { + MigrationPass &Pass; +public: + NonObjCToObjCCaster(MigrationPass &pass) : Pass(pass) { } + + bool VisitCastExpr(CastExpr *E) { + if (E->getCastKind() != CK_AnyPointerToObjCPointerCast + && E->getCastKind() != CK_BitCast) + return true; + + QualType castType = E->getType(); + Expr *castExpr = E->getSubExpr(); + QualType castExprType = castExpr->getType(); + + if (castType->isObjCObjectPointerType() && + castExprType->isObjCObjectPointerType()) + return true; + if (!castType->isObjCObjectPointerType() && + !castExprType->isObjCObjectPointerType()) + return true; + + bool exprRetainable = castExprType->isObjCIndirectLifetimeType(); + bool castRetainable = castType->isObjCIndirectLifetimeType(); + if (exprRetainable == castRetainable) return true; + + if (castExpr->isNullPointerConstant(Pass.Ctx, + Expr::NPC_ValueDependentIsNull)) + return true; + + SourceLocation loc = castExpr->getExprLoc(); + if (loc.isValid() && Pass.Ctx.getSourceManager().isInSystemHeader(loc)) + return true; + + if (castType->isObjCObjectPointerType()) + transformNonObjCToObjCCast(E); + else + transformObjCToNonObjCCast(E); + + return true; + } + +private: + void transformNonObjCToObjCCast(CastExpr *E) { + if (!E) return; + + // Global vars are assumed that are cast as unretained. + if (isGlobalVar(E)) + if (E->getSubExpr()->getType()->isPointerType()) { + castToObjCObject(E, /*retained=*/false); + return; + } + + // If the cast is directly over the result of a Core Foundation function + // try to figure out whether it should be cast as retained or unretained. + Expr *inner = E->IgnoreParenCasts(); + if (CallExpr *callE = dyn_cast<CallExpr>(inner)) { + if (FunctionDecl *FD = callE->getDirectCallee()) { + if (FD->getAttr<CFReturnsRetainedAttr>()) { + castToObjCObject(E, /*retained=*/true); + return; + } + if (FD->getAttr<CFReturnsNotRetainedAttr>()) { + castToObjCObject(E, /*retained=*/false); + return; + } + if (FD->isGlobal() && + FD->getIdentifier() && + ento::cocoa::isRefType(E->getSubExpr()->getType(), "CF", + FD->getIdentifier()->getName())) { + StringRef fname = FD->getIdentifier()->getName(); + if (fname.endswith("Retain") || + fname.find("Create") != StringRef::npos || + fname.find("Copy") != StringRef::npos) { + castToObjCObject(E, /*retained=*/true); + return; + } + + if (fname.find("Get") != StringRef::npos) { + castToObjCObject(E, /*retained=*/false); + return; + } + } + } + } + } + + void castToObjCObject(CastExpr *E, bool retained) { + TransformActions &TA = Pass.TA; + + // We will remove the compiler diagnostic. + if (!TA.hasDiagnostic(diag::err_arc_mismatched_cast, + diag::err_arc_cast_requires_bridge, + E->getLocStart())) + return; + + Transaction Trans(TA); + TA.clearDiagnostic(diag::err_arc_mismatched_cast, + diag::err_arc_cast_requires_bridge, + E->getLocStart()); + if (CStyleCastExpr *CCE = dyn_cast<CStyleCastExpr>(E)) { + TA.insertAfterToken(CCE->getLParenLoc(), retained ? "__bridge_transfer " + : "__bridge "); + } else { + SourceLocation insertLoc = E->getSubExpr()->getLocStart(); + llvm::SmallString<128> newCast; + newCast += '('; + newCast += retained ? "__bridge_transfer " : "__bridge "; + newCast += E->getType().getAsString(Pass.Ctx.PrintingPolicy); + newCast += ')'; + + if (isa<ParenExpr>(E->getSubExpr())) { + TA.insert(insertLoc, newCast.str()); + } else { + newCast += '('; + TA.insert(insertLoc, newCast.str()); + TA.insertAfterToken(E->getLocEnd(), ")"); + } + } + } + + void transformObjCToNonObjCCast(CastExpr *E) { + // FIXME: Handle these casts. + return; +#if 0 + TransformActions &TA = Pass.TA; + + // We will remove the compiler diagnostic. + if (!TA.hasDiagnostic(diag::err_arc_mismatched_cast, + diag::err_arc_cast_requires_bridge, + E->getLocStart())) + return; + + Transaction Trans(TA); + TA.clearDiagnostic(diag::err_arc_mismatched_cast, + diag::err_arc_cast_requires_bridge, + E->getLocStart()); + + assert(!E->getType()->isObjCObjectPointerType()); + + bool shouldCast = !isa<CStyleCastExpr>(E) && + !E->getType()->getPointeeType().isConstQualified(); + SourceLocation loc = E->getSubExpr()->getLocStart(); + if (isa<ParenExpr>(E->getSubExpr())) { + TA.insert(loc, shouldCast ? "(void*)objc_unretainedPointer" + : "objc_unretainedPointer"); + } else { + TA.insert(loc, shouldCast ? "(void*)objc_unretainedPointer(" + : "objc_unretainedPointer("); + TA.insertAfterToken(E->getLocEnd(), ")"); + } +#endif + } + + static bool isGlobalVar(Expr *E) { + E = E->IgnoreParenCasts(); + if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) + return DRE->getDecl()->getDeclContext()->isFileContext(); + if (ConditionalOperator *condOp = dyn_cast<ConditionalOperator>(E)) + return isGlobalVar(condOp->getTrueExpr()) && + isGlobalVar(condOp->getFalseExpr()); + + return false; + } +}; + +} // end anonymous namespace + +static void castNonObjCToObjC(MigrationPass &pass) { + NonObjCToObjCCaster trans(pass); + trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl()); +} + +//===----------------------------------------------------------------------===// +// rewriteAllocCopyWithZone +//===----------------------------------------------------------------------===// + +namespace { + +class AllocCopyWithZoneRewriter : + public RecursiveASTVisitor<AllocCopyWithZoneRewriter> { + Decl *Dcl; + Stmt *Body; + MigrationPass &Pass; + + Selector allocWithZoneSel; + Selector copyWithZoneSel; + Selector mutableCopyWithZoneSel; + Selector zoneSel; + IdentifierInfo *NSZoneII; + + std::vector<DeclStmt *> NSZoneVars; + std::vector<Expr *> Removals; + +public: + AllocCopyWithZoneRewriter(Decl *D, MigrationPass &pass) + : Dcl(D), Body(0), Pass(pass) { + SelectorTable &sels = pass.Ctx.Selectors; + IdentifierTable &ids = pass.Ctx.Idents; + allocWithZoneSel = sels.getUnarySelector(&ids.get("allocWithZone")); + copyWithZoneSel = sels.getUnarySelector(&ids.get("copyWithZone")); + mutableCopyWithZoneSel = sels.getUnarySelector( + &ids.get("mutableCopyWithZone")); + zoneSel = sels.getNullarySelector(&ids.get("zone")); + NSZoneII = &ids.get("_NSZone"); + } + + void transformBody(Stmt *body) { + Body = body; + // Don't change allocWithZone/copyWithZone messages inside + // custom implementations of such methods, it can lead to infinite loops. + if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(Dcl)) { + Selector sel = MD->getSelector(); + if (sel == allocWithZoneSel || + sel == copyWithZoneSel || + sel == mutableCopyWithZoneSel || + sel == zoneSel) + return; + } + + TraverseStmt(body); + } + + ~AllocCopyWithZoneRewriter() { + for (std::vector<DeclStmt *>::reverse_iterator + I = NSZoneVars.rbegin(), E = NSZoneVars.rend(); I != E; ++I) { + DeclStmt *DS = *I; + DeclGroupRef group = DS->getDeclGroup(); + std::vector<Expr *> varRemovals = Removals; + + bool areAllVarsUnused = true; + for (std::reverse_iterator<DeclGroupRef::iterator> + DI(group.end()), DE(group.begin()); DI != DE; ++DI) { + VarDecl *VD = cast<VarDecl>(*DI); + if (isNSZoneVarUsed(VD, varRemovals)) { + areAllVarsUnused = false; + break; + } + varRemovals.push_back(VD->getInit()); + } + + if (areAllVarsUnused) { + Transaction Trans(Pass.TA); + clearUnavailableDiags(DS); + Pass.TA.removeStmt(DS); + Removals.swap(varRemovals); + } + } + } + + bool VisitObjCMessageExpr(ObjCMessageExpr *E) { + if (!isAllocCopyWithZoneCall(E)) + return true; + Expr *arg = E->getArg(0); + if (paramToAllocWithZoneHasSideEffects(arg)) + return true; + + Pass.TA.startTransaction(); + + clearUnavailableDiags(arg); + Pass.TA.clearDiagnostic(diag::err_unavailable_message, + E->getReceiverRange().getBegin()); + + Pass.TA.remove(SourceRange(E->getSelectorLoc(), arg->getLocEnd())); + StringRef rewrite; + if (E->getSelector() == allocWithZoneSel) + rewrite = "alloc"; + else if (E->getSelector() == copyWithZoneSel) + rewrite = "copy"; + else { + assert(E->getSelector() == mutableCopyWithZoneSel); + rewrite = "mutableCopy"; + } + Pass.TA.insert(E->getSelectorLoc(), rewrite); + + bool failed = Pass.TA.commitTransaction(); + if (!failed) + Removals.push_back(arg); + + return true; + } + + bool VisitDeclStmt(DeclStmt *DS) { + DeclGroupRef group = DS->getDeclGroup(); + if (group.begin() == group.end()) + return true; + for (DeclGroupRef::iterator + DI = group.begin(), DE = group.end(); DI != DE; ++DI) + if (!isRemovableNSZoneVar(*DI)) + return true; + + NSZoneVars.push_back(DS); + return true; + } + +private: + bool isRemovableNSZoneVar(Decl *D) { + if (VarDecl *VD = dyn_cast<VarDecl>(D)) { + if (isNSZone(VD->getType())) + return !paramToAllocWithZoneHasSideEffects(VD->getInit()); + } + return false; + } + + bool isNSZone(RecordDecl *RD) { + return RD && RD->getIdentifier() == NSZoneII; + } + + bool isNSZone(QualType Ty) { + QualType pointee = Ty->getPointeeType(); + if (pointee.isNull()) + return false; + if (const RecordType *recT = pointee->getAsStructureType()) + return isNSZone(recT->getDecl()); + return false; + } + + bool isNSZoneVarUsed(VarDecl *D, std::vector<Expr *> &removals) { + llvm::DenseSet<Expr *> refs; + + ReferenceCollector refColl(refs); + refColl.lookFor(D, Body); + + ReferenceClear refClear(refs); + refClear.clearRefsIn(removals.begin(), removals.end()); + + return !refs.empty(); + } + + bool isAllocCopyWithZoneCall(ObjCMessageExpr *E) { + if (E->getNumArgs() == 1 && + E->getSelector() == allocWithZoneSel && + (E->isClassMessage() || + Pass.TA.hasDiagnostic(diag::err_unavailable_message, + E->getReceiverRange().getBegin()))) + return true; + + return E->isInstanceMessage() && + E->getNumArgs() == 1 && + (E->getSelector() == copyWithZoneSel || + E->getSelector() == mutableCopyWithZoneSel); + } + + bool isZoneCall(ObjCMessageExpr *E) { + return E->isInstanceMessage() && + E->getNumArgs() == 0 && + E->getSelector() == zoneSel; + } + + bool paramToAllocWithZoneHasSideEffects(Expr *E) { + if (!HasSideEffects(E, Pass.Ctx)) + return false; + E = E->IgnoreParenCasts(); + ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E); + if (!ME) + return true; + if (!isZoneCall(ME)) + return true; + return HasSideEffects(ME->getInstanceReceiver(), Pass.Ctx); + } + + void clearUnavailableDiags(Stmt *S) { + if (S) + Pass.TA.clearDiagnostic(diag::err_unavailable, + diag::err_unavailable_message, + S->getSourceRange()); + } +}; + +} // end anonymous namespace + +static void rewriteAllocCopyWithZone(MigrationPass &pass) { + BodyTransform<AllocCopyWithZoneRewriter> trans(pass); + trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl()); +} + +//===----------------------------------------------------------------------===// +// rewriteAutoreleasePool +//===----------------------------------------------------------------------===// + +/// \brief 'Loc' is the end of a statement range. This returns the location +/// immediately after the semicolon following the statement. +/// If no semicolon is found or the location is inside a macro, the returned +/// source location will be invalid. +static SourceLocation findLocationAfterSemi(ASTContext &Ctx, + SourceLocation loc) { + SourceManager &SM = Ctx.getSourceManager(); + if (loc.isMacroID()) { + if (!SM.isAtEndOfMacroInstantiation(loc)) + return SourceLocation(); + loc = SM.getInstantiationRange(loc).second; + } + loc = Lexer::getLocForEndOfToken(loc, /*Offset=*/0, SM, Ctx.getLangOptions()); + + // Break down the source location. + std::pair<FileID, unsigned> locInfo = SM.getDecomposedLoc(loc); + + // Try to load the file buffer. + bool invalidTemp = false; + llvm::StringRef file = SM.getBufferData(locInfo.first, &invalidTemp); + if (invalidTemp) + return SourceLocation(); + + const char *tokenBegin = file.data() + locInfo.second; + + // Lex from the start of the given location. + Lexer lexer(SM.getLocForStartOfFile(locInfo.first), + Ctx.getLangOptions(), + file.begin(), tokenBegin, file.end()); + Token tok; + lexer.LexFromRawLexer(tok); + if (tok.isNot(tok::semi)) + return SourceLocation(); + + return tok.getLocation().getFileLocWithOffset(1); +} + +namespace { + +class AutoreleasePoolRewriter + : public RecursiveASTVisitor<AutoreleasePoolRewriter> { +public: + AutoreleasePoolRewriter(Decl *D, MigrationPass &pass) + : Dcl(D), Body(0), Pass(pass) { + PoolII = &pass.Ctx.Idents.get("NSAutoreleasePool"); + DrainSel = pass.Ctx.Selectors.getNullarySelector( + &pass.Ctx.Idents.get("drain")); + } + + void transformBody(Stmt *body) { + Body = body; + TraverseStmt(body); + } + + ~AutoreleasePoolRewriter() { + llvm::SmallVector<VarDecl *, 8> VarsToHandle; + + for (std::map<VarDecl *, PoolVarInfo>::iterator + I = PoolVars.begin(), E = PoolVars.end(); I != E; ++I) { + VarDecl *var = I->first; + PoolVarInfo &info = I->second; + + // Check that we can handle/rewrite all references of the pool. + + ReferenceClear refClear(info.Refs); + refClear.clearRefsIn(info.Dcl); + for (llvm::SmallVectorImpl<PoolScope>::iterator + scpI = info.Scopes.begin(), + scpE = info.Scopes.end(); scpI != scpE; ++scpI) { + PoolScope &scope = *scpI; + refClear.clearRefsIn(*scope.Begin); + refClear.clearRefsIn(*scope.End); + refClear.clearRefsIn(scope.Releases.begin(), scope.Releases.end()); + } + + // Even if one reference is not handled we will not do anything about that + // pool variable. + if (info.Refs.empty()) + VarsToHandle.push_back(var); + } + + for (unsigned i = 0, e = VarsToHandle.size(); i != e; ++i) { + PoolVarInfo &info = PoolVars[VarsToHandle[i]]; + + Transaction Trans(Pass.TA); + + clearUnavailableDiags(info.Dcl); + Pass.TA.removeStmt(info.Dcl); + + // Add "@autoreleasepool { }" + for (llvm::SmallVectorImpl<PoolScope>::iterator + scpI = info.Scopes.begin(), + scpE = info.Scopes.end(); scpI != scpE; ++scpI) { + PoolScope &scope = *scpI; + clearUnavailableDiags(*scope.Begin); + clearUnavailableDiags(*scope.End); + if (scope.IsFollowedBySimpleReturnStmt) { + // Include the return in the scope. + Pass.TA.replaceStmt(*scope.Begin, "@autoreleasepool {"); + Pass.TA.removeStmt(*scope.End); + Stmt::child_iterator retI = scope.End; + ++retI; + SourceLocation afterSemi = findLocationAfterSemi(Pass.Ctx, + (*retI)->getLocEnd()); + assert(afterSemi.isValid() && + "Didn't we check before setting IsFollowedBySimpleReturnStmt " + "to true?"); + Pass.TA.insertAfterToken(afterSemi, "\n}"); + Pass.TA.increaseIndentation( + SourceRange(scope.getIndentedRange().getBegin(), + (*retI)->getLocEnd()), + scope.CompoundParent->getLocStart()); + } else { + Pass.TA.replaceStmt(*scope.Begin, "@autoreleasepool {"); + Pass.TA.replaceStmt(*scope.End, "}"); + Pass.TA.increaseIndentation(scope.getIndentedRange(), + scope.CompoundParent->getLocStart()); + } + } + + // Remove rest of pool var references. + for (llvm::SmallVectorImpl<PoolScope>::iterator + scpI = info.Scopes.begin(), + scpE = info.Scopes.end(); scpI != scpE; ++scpI) { + PoolScope &scope = *scpI; + for (llvm::SmallVectorImpl<ObjCMessageExpr *>::iterator + relI = scope.Releases.begin(), + relE = scope.Releases.end(); relI != relE; ++relI) { + clearUnavailableDiags(*relI); + Pass.TA.removeStmt(*relI); + } + } + } + } + + bool VisitCompoundStmt(CompoundStmt *S) { + llvm::SmallVector<PoolScope, 4> Scopes; + + for (Stmt::child_iterator + I = S->body_begin(), E = S->body_end(); I != E; ++I) { + Stmt *child = getEssential(*I); + if (DeclStmt *DclS = dyn_cast<DeclStmt>(child)) { + if (DclS->isSingleDecl()) { + if (VarDecl *VD = dyn_cast<VarDecl>(DclS->getSingleDecl())) { + if (isNSAutoreleasePool(VD->getType())) { + PoolVarInfo &info = PoolVars[VD]; + info.Dcl = DclS; + ReferenceCollector refColl(info.Refs); + refColl.lookFor(VD, S); + // Does this statement follow the pattern: + // NSAutoreleasePool * pool = [NSAutoreleasePool new]; + if (isPoolCreation(VD->getInit())) { + Scopes.push_back(PoolScope()); + Scopes.back().PoolVar = VD; + Scopes.back().CompoundParent = S; + Scopes.back().Begin = I; + } + } + } + } + } else if (BinaryOperator *bop = dyn_cast<BinaryOperator>(child)) { + if (DeclRefExpr *dref = dyn_cast<DeclRefExpr>(bop->getLHS())) { + if (VarDecl *VD = dyn_cast<VarDecl>(dref->getDecl())) { + // Does this statement follow the pattern: + // pool = [NSAutoreleasePool new]; + if (isNSAutoreleasePool(VD->getType()) && + isPoolCreation(bop->getRHS())) { + Scopes.push_back(PoolScope()); + Scopes.back().PoolVar = VD; + Scopes.back().CompoundParent = S; + Scopes.back().Begin = I; + } + } + } + } + + if (Scopes.empty()) + continue; + + if (isPoolDrain(Scopes.back().PoolVar, child)) { + PoolScope &scope = Scopes.back(); + scope.End = I; + handlePoolScope(scope, S); + Scopes.pop_back(); + } + } + return true; + } + +private: + void clearUnavailableDiags(Stmt *S) { + if (S) + Pass.TA.clearDiagnostic(diag::err_unavailable, + diag::err_unavailable_message, + S->getSourceRange()); + } + + struct PoolScope { + VarDecl *PoolVar; + CompoundStmt *CompoundParent; + Stmt::child_iterator Begin; + Stmt::child_iterator End; + bool IsFollowedBySimpleReturnStmt; + llvm::SmallVector<ObjCMessageExpr *, 4> Releases; + + PoolScope() : PoolVar(0), CompoundParent(0), Begin(), End(), + IsFollowedBySimpleReturnStmt(false) { } + + SourceRange getIndentedRange() const { + Stmt::child_iterator rangeS = Begin; + ++rangeS; + if (rangeS == End) + return SourceRange(); + Stmt::child_iterator rangeE = Begin; + for (Stmt::child_iterator I = rangeS; I != End; ++I) + ++rangeE; + return SourceRange((*rangeS)->getLocStart(), (*rangeE)->getLocEnd()); + } + }; + + class NameReferenceChecker : public RecursiveASTVisitor<NameReferenceChecker>{ + ASTContext &Ctx; + SourceRange ScopeRange; + SourceLocation &referenceLoc, &declarationLoc; + + public: + NameReferenceChecker(ASTContext &ctx, PoolScope &scope, + SourceLocation &referenceLoc, + SourceLocation &declarationLoc) + : Ctx(ctx), referenceLoc(referenceLoc), + declarationLoc(declarationLoc) { + ScopeRange = SourceRange((*scope.Begin)->getLocStart(), + (*scope.End)->getLocStart()); + } + + bool VisitDeclRefExpr(DeclRefExpr *E) { + return checkRef(E->getLocation(), E->getDecl()->getLocation()); + } + + bool VisitBlockDeclRefExpr(BlockDeclRefExpr *E) { + return checkRef(E->getLocation(), E->getDecl()->getLocation()); + } + + bool VisitTypedefTypeLoc(TypedefTypeLoc TL) { + return checkRef(TL.getBeginLoc(), TL.getTypedefNameDecl()->getLocation()); + } + + bool VisitTagTypeLoc(TagTypeLoc TL) { + return checkRef(TL.getBeginLoc(), TL.getDecl()->getLocation()); + } + + private: + bool checkRef(SourceLocation refLoc, SourceLocation declLoc) { + if (isInScope(declLoc)) { + referenceLoc = refLoc; + declarationLoc = declLoc; + return false; + } + return true; + } + + bool isInScope(SourceLocation loc) { + SourceManager &SM = Ctx.getSourceManager(); + if (SM.isBeforeInTranslationUnit(loc, ScopeRange.getBegin())) + return false; + return SM.isBeforeInTranslationUnit(loc, ScopeRange.getEnd()); + } + }; + + void handlePoolScope(PoolScope &scope, CompoundStmt *compoundS) { + // Check that all names declared inside the scope are not used + // outside the scope. + { + bool nameUsedOutsideScope = false; + SourceLocation referenceLoc, declarationLoc; + Stmt::child_iterator SI = scope.End, SE = compoundS->body_end(); + ++SI; + // Check if the autoreleasepool scope is followed by a simple return + // statement, in which case we will include the return in the scope. + if (SI != SE) + if (ReturnStmt *retS = dyn_cast<ReturnStmt>(*SI)) + if ((retS->getRetValue() == 0 || + isa<DeclRefExpr>(retS->getRetValue()->IgnoreParenCasts())) && + findLocationAfterSemi(Pass.Ctx, retS->getLocEnd()).isValid()) { + scope.IsFollowedBySimpleReturnStmt = true; + ++SI; // the return will be included in scope, don't check it. + } + + for (; SI != SE; ++SI) { + nameUsedOutsideScope = !NameReferenceChecker(Pass.Ctx, scope, + referenceLoc, + declarationLoc).TraverseStmt(*SI); + if (nameUsedOutsideScope) + break; + } + + // If not all references were cleared it means some variables/typenames/etc + // declared inside the pool scope are used outside of it. + // We won't try to rewrite the pool. + if (nameUsedOutsideScope) { + Pass.TA.reportError("a name is referenced outside the " + "NSAutoreleasePool scope that it was declared in", referenceLoc); + Pass.TA.reportNote("name declared here", declarationLoc); + Pass.TA.reportNote("intended @autoreleasepool scope begins here", + (*scope.Begin)->getLocStart()); + Pass.TA.reportNote("intended @autoreleasepool scope ends here", + (*scope.End)->getLocStart()); + return; + } + } + + // Collect all releases of the pool; they will be removed. + { + ReleaseCollector releaseColl(scope.PoolVar, scope.Releases); + Stmt::child_iterator I = scope.Begin; + ++I; + for (; I != scope.End; ++I) + releaseColl.TraverseStmt(*I); + } + + PoolVars[scope.PoolVar].Scopes.push_back(scope); + } + + bool isPoolCreation(Expr *E) { + if (!E) return false; + E = getEssential(E); + ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E); + if (!ME) return false; + if (ME->getMethodFamily() == OMF_new && + ME->getReceiverKind() == ObjCMessageExpr::Class && + isNSAutoreleasePool(ME->getReceiverInterface())) + return true; + if (ME->getReceiverKind() == ObjCMessageExpr::Instance && + ME->getMethodFamily() == OMF_init) { + Expr *rec = getEssential(ME->getInstanceReceiver()); + if (ObjCMessageExpr *recME = dyn_cast_or_null<ObjCMessageExpr>(rec)) { + if (recME->getMethodFamily() == OMF_alloc && + recME->getReceiverKind() == ObjCMessageExpr::Class && + isNSAutoreleasePool(recME->getReceiverInterface())) + return true; + } + } + + return false; + } + + bool isPoolDrain(VarDecl *poolVar, Stmt *S) { + if (!S) return false; + S = getEssential(S); + ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(S); + if (!ME) return false; + if (ME->getReceiverKind() == ObjCMessageExpr::Instance) { + Expr *rec = getEssential(ME->getInstanceReceiver()); + if (DeclRefExpr *dref = dyn_cast<DeclRefExpr>(rec)) + if (dref->getDecl() == poolVar) + return ME->getMethodFamily() == OMF_release || + ME->getSelector() == DrainSel; + } + + return false; + } + + bool isNSAutoreleasePool(ObjCInterfaceDecl *IDecl) { + return IDecl && IDecl->getIdentifier() == PoolII; + } + + bool isNSAutoreleasePool(QualType Ty) { + QualType pointee = Ty->getPointeeType(); + if (pointee.isNull()) + return false; + if (const ObjCInterfaceType *interT = pointee->getAs<ObjCInterfaceType>()) + return isNSAutoreleasePool(interT->getDecl()); + return false; + } + + static Expr *getEssential(Expr *E) { + return cast<Expr>(getEssential((Stmt*)E)); + } + static Stmt *getEssential(Stmt *S) { + if (ExprWithCleanups *EWC = dyn_cast<ExprWithCleanups>(S)) + S = EWC->getSubExpr(); + if (Expr *E = dyn_cast<Expr>(S)) + S = E->IgnoreParenCasts(); + return S; + } + + Decl *Dcl; + Stmt *Body; + MigrationPass &Pass; + + IdentifierInfo *PoolII; + Selector DrainSel; + + struct PoolVarInfo { + DeclStmt *Dcl; + llvm::DenseSet<Expr *> Refs; + llvm::SmallVector<PoolScope, 2> Scopes; + + PoolVarInfo() : Dcl(0) { } + }; + + std::map<VarDecl *, PoolVarInfo> PoolVars; +}; + +} // anonymous namespace + +static void rewriteAutoreleasePool(MigrationPass &pass) { + BodyTransform<AutoreleasePoolRewriter> trans(pass); + trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl()); +} + +//===----------------------------------------------------------------------===// +// removeRetainReleaseDealloc +//===----------------------------------------------------------------------===// + +namespace { + +class RetainReleaseDeallocRemover : + public RecursiveASTVisitor<RetainReleaseDeallocRemover> { + Decl *Dcl; + Stmt *Body; + MigrationPass &Pass; + + llvm::DenseSet<Expr *> Removables; + llvm::OwningPtr<ParentMap> StmtMap; + +public: + RetainReleaseDeallocRemover(Decl *D, MigrationPass &pass) + : Dcl(D), Body(0), Pass(pass) { } + + void transformBody(Stmt *body) { + Body = body; + RemovablesCollector(Removables).TraverseStmt(body); + StmtMap.reset(new ParentMap(body)); + TraverseStmt(body); + } + + bool VisitObjCMessageExpr(ObjCMessageExpr *E) { + switch (E->getMethodFamily()) { + default: + return true; + case OMF_retain: + case OMF_release: + case OMF_autorelease: + if (E->getReceiverKind() == ObjCMessageExpr::Instance) + if (Expr *rec = E->getInstanceReceiver()) { + rec = rec->IgnoreParenImpCasts(); + if (rec->getType().getObjCLifetime() == Qualifiers::OCL_ExplicitNone){ + std::string err = "It is not safe to remove '"; + err += E->getSelector().getAsString() + "' message on " + "an __unsafe_unretained type"; + Pass.TA.reportError(err, rec->getLocStart()); + return true; + } + } + case OMF_dealloc: + break; + } + + switch (E->getReceiverKind()) { + default: + return true; + case ObjCMessageExpr::SuperInstance: { + Transaction Trans(Pass.TA); + Pass.TA.clearDiagnostic(diag::err_arc_illegal_explicit_message, + diag::err_unavailable, + diag::err_unavailable_message, + E->getSuperLoc()); + if (tryRemoving(E)) + return true; + Pass.TA.replace(E->getSourceRange(), "self"); + return true; + } + case ObjCMessageExpr::Instance: + break; + } + + Expr *rec = E->getInstanceReceiver(); + if (!rec) return true; + + Transaction Trans(Pass.TA); + Pass.TA.clearDiagnostic(diag::err_arc_illegal_explicit_message, + diag::err_unavailable, + diag::err_unavailable_message, + rec->getExprLoc()); + if (!HasSideEffects(E, Pass.Ctx)) { + if (tryRemoving(E)) + return true; + } + Pass.TA.replace(E->getSourceRange(), rec->getSourceRange()); + + return true; + } + +private: + bool isRemovable(Expr *E) const { + return Removables.count(E); + } + + bool tryRemoving(Expr *E) const { + if (isRemovable(E)) { + Pass.TA.removeStmt(E); + return true; + } + + if (ParenExpr *parenE = dyn_cast_or_null<ParenExpr>(StmtMap->getParent(E))) + return tryRemoving(parenE); + + if (BinaryOperator * + bopE = dyn_cast_or_null<BinaryOperator>(StmtMap->getParent(E))) { + if (bopE->getOpcode() == BO_Comma && bopE->getLHS() == E && + isRemovable(bopE)) { + Pass.TA.replace(bopE->getSourceRange(), bopE->getRHS()->getSourceRange()); + return true; + } + } + + return false; + } + +}; + +} // anonymous namespace + +static void removeRetainReleaseDealloc(MigrationPass &pass) { + BodyTransform<RetainReleaseDeallocRemover> trans(pass); + trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl()); +} + +//===----------------------------------------------------------------------===// +// removeEmptyStatements +//===----------------------------------------------------------------------===// + +namespace { + +class EmptyStatementsRemover : + public RecursiveASTVisitor<EmptyStatementsRemover> { + MigrationPass &Pass; + llvm::DenseSet<unsigned> MacroLocs; + +public: + EmptyStatementsRemover(MigrationPass &pass) : Pass(pass) { + for (unsigned i = 0, e = Pass.ARCMTMacroLocs.size(); i != e; ++i) + MacroLocs.insert(Pass.ARCMTMacroLocs[i].getRawEncoding()); + } + + bool TraverseStmtExpr(StmtExpr *E) { + CompoundStmt *S = E->getSubStmt(); + for (CompoundStmt::body_iterator + I = S->body_begin(), E = S->body_end(); I != E; ++I) { + if (I != E - 1) + check(*I); + TraverseStmt(*I); + } + return true; + } + + bool VisitCompoundStmt(CompoundStmt *S) { + for (CompoundStmt::body_iterator + I = S->body_begin(), E = S->body_end(); I != E; ++I) + check(*I); + return true; + } + + bool isMacroLoc(SourceLocation loc) { + if (loc.isInvalid()) return false; + return MacroLocs.count(loc.getRawEncoding()); + } + + ASTContext &getContext() { return Pass.Ctx; } + +private: + /// \brief Returns true if the statement became empty due to previous + /// transformations. + class EmptyChecker : public StmtVisitor<EmptyChecker, bool> { + EmptyStatementsRemover &Trans; + + public: + EmptyChecker(EmptyStatementsRemover &trans) : Trans(trans) { } + + bool VisitNullStmt(NullStmt *S) { + return Trans.isMacroLoc(S->getLeadingEmptyMacroLoc()); + } + bool VisitCompoundStmt(CompoundStmt *S) { + if (S->body_empty()) + return false; // was already empty, not because of transformations. + for (CompoundStmt::body_iterator + I = S->body_begin(), E = S->body_end(); I != E; ++I) + if (!Visit(*I)) + return false; + return true; + } + bool VisitIfStmt(IfStmt *S) { + if (S->getConditionVariable()) + return false; + Expr *condE = S->getCond(); + if (!condE) + return false; + if (HasSideEffects(condE, Trans.getContext())) + return false; + if (!S->getThen() || !Visit(S->getThen())) + return false; + if (S->getElse() && !Visit(S->getElse())) + return false; + return true; + } + bool VisitWhileStmt(WhileStmt *S) { + if (S->getConditionVariable()) + return false; + Expr *condE = S->getCond(); + if (!condE) + return false; + if (HasSideEffects(condE, Trans.getContext())) + return false; + if (!S->getBody()) + return false; + return Visit(S->getBody()); + } + bool VisitDoStmt(DoStmt *S) { + Expr *condE = S->getCond(); + if (!condE) + return false; + if (HasSideEffects(condE, Trans.getContext())) + return false; + if (!S->getBody()) + return false; + return Visit(S->getBody()); + } + bool VisitObjCForCollectionStmt(ObjCForCollectionStmt *S) { + Expr *Exp = S->getCollection(); + if (!Exp) + return false; + if (HasSideEffects(Exp, Trans.getContext())) + return false; + if (!S->getBody()) + return false; + return Visit(S->getBody()); + } + bool VisitObjCAutoreleasePoolStmt(ObjCAutoreleasePoolStmt *S) { + if (!S->getSubStmt()) + return false; + return Visit(S->getSubStmt()); + } + }; + + void check(Stmt *S) { + if (!S) return; + if (EmptyChecker(*this).Visit(S)) { + Transaction Trans(Pass.TA); + Pass.TA.removeStmt(S); + } + } +}; + +} // anonymous namespace + +static void removeEmptyStatements(MigrationPass &pass) { + EmptyStatementsRemover(pass).TraverseDecl(pass.Ctx.getTranslationUnitDecl()); + + for (unsigned i = 0, e = pass.ARCMTMacroLocs.size(); i != e; ++i) { + Transaction Trans(pass.TA); + pass.TA.remove(pass.ARCMTMacroLocs[i]); + } +} + +//===----------------------------------------------------------------------===// +// changeIvarsOfAssignProperties. +//===----------------------------------------------------------------------===// + +namespace { + +class AssignPropertiesTrans { + MigrationPass &Pass; + struct PropData { + ObjCPropertyDecl *PropD; + ObjCIvarDecl *IvarD; + bool ShouldChangeToWeak; + SourceLocation ArcPropAssignErrorLoc; + }; + + typedef llvm::SmallVector<PropData, 2> PropsTy; + typedef llvm::DenseMap<unsigned, PropsTy> PropsMapTy; + PropsMapTy PropsMap; + +public: + AssignPropertiesTrans(MigrationPass &pass) : Pass(pass) { } + + void doTransform(ObjCImplementationDecl *D) { + SourceManager &SM = Pass.Ctx.getSourceManager(); + + ObjCInterfaceDecl *IFace = D->getClassInterface(); + for (ObjCInterfaceDecl::prop_iterator + I = IFace->prop_begin(), E = IFace->prop_end(); I != E; ++I) { + ObjCPropertyDecl *propD = *I; + unsigned loc = SM.getInstantiationLoc(propD->getAtLoc()).getRawEncoding(); + PropsTy &props = PropsMap[loc]; + props.push_back(PropData()); + props.back().PropD = propD; + props.back().IvarD = 0; + props.back().ShouldChangeToWeak = false; + } + + typedef DeclContext::specific_decl_iterator<ObjCPropertyImplDecl> + prop_impl_iterator; + for (prop_impl_iterator + I = prop_impl_iterator(D->decls_begin()), + E = prop_impl_iterator(D->decls_end()); I != E; ++I) { + VisitObjCPropertyImplDecl(*I); + } + + for (PropsMapTy::iterator + I = PropsMap.begin(), E = PropsMap.end(); I != E; ++I) { + SourceLocation atLoc = SourceLocation::getFromRawEncoding(I->first); + PropsTy &props = I->second; + if (shouldApplyWeakToAllProp(props)) { + if (changeAssignToWeak(atLoc)) { + // Couldn't add the 'weak' property attribute, + // try adding __unsafe_unretained. + applyUnsafeUnretained(props); + } else { + for (PropsTy::iterator + PI = props.begin(), PE = props.end(); PI != PE; ++PI) { + applyWeak(*PI); + } + } + } else { + // We should not add 'weak' attribute since not all properties need it. + // So just add __unsafe_unretained to the ivars. + applyUnsafeUnretained(props); + } + } + } + + bool shouldApplyWeakToAllProp(PropsTy &props) { + for (PropsTy::iterator + PI = props.begin(), PE = props.end(); PI != PE; ++PI) { + if (!PI->ShouldChangeToWeak) + return false; + } + return true; + } + + void applyWeak(PropData &prop) { + assert(!Pass.Ctx.getLangOptions().ObjCNoAutoRefCountRuntime); + + Transaction Trans(Pass.TA); + Pass.TA.insert(prop.IvarD->getLocation(), "__weak "); + Pass.TA.clearDiagnostic(diag::err_arc_assign_property_lifetime, + prop.ArcPropAssignErrorLoc); + } + + void applyUnsafeUnretained(PropsTy &props) { + for (PropsTy::iterator + PI = props.begin(), PE = props.end(); PI != PE; ++PI) { + if (PI->ShouldChangeToWeak) { + Transaction Trans(Pass.TA); + Pass.TA.insert(PI->IvarD->getLocation(), "__unsafe_unretained "); + Pass.TA.clearDiagnostic(diag::err_arc_assign_property_lifetime, + PI->ArcPropAssignErrorLoc); + } + } + } + + bool VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) { + SourceManager &SM = Pass.Ctx.getSourceManager(); + + if (D->getPropertyImplementation() != ObjCPropertyImplDecl::Synthesize) + return true; + ObjCPropertyDecl *propD = D->getPropertyDecl(); + if (!propD || propD->isInvalidDecl()) + return true; + ObjCIvarDecl *ivarD = D->getPropertyIvarDecl(); + if (!ivarD || ivarD->isInvalidDecl()) + return true; + if (!(propD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_assign)) + return true; + if (isa<AttributedType>(ivarD->getType().getTypePtr())) + return true; + if (ivarD->getType().getLocalQualifiers().getObjCLifetime() + != Qualifiers::OCL_Strong) + return true; + if (!Pass.TA.hasDiagnostic( + diag::err_arc_assign_property_lifetime, D->getLocation())) + return true; + + // There is a "error: existing ivar for assign property must be + // __unsafe_unretained"; fix it. + + if (Pass.Ctx.getLangOptions().ObjCNoAutoRefCountRuntime) { + // We will just add __unsafe_unretained to the ivar. + Transaction Trans(Pass.TA); + Pass.TA.insert(ivarD->getLocation(), "__unsafe_unretained "); + Pass.TA.clearDiagnostic( + diag::err_arc_assign_property_lifetime, D->getLocation()); + } else { + // Mark that we want the ivar to become weak. + unsigned loc = SM.getInstantiationLoc(propD->getAtLoc()).getRawEncoding(); + PropsTy &props = PropsMap[loc]; + for (PropsTy::iterator I = props.begin(), E = props.end(); I != E; ++I) { + if (I->PropD == propD) { + I->IvarD = ivarD; + I->ShouldChangeToWeak = true; + I->ArcPropAssignErrorLoc = D->getLocation(); + } + } + } + + return true; + } + +private: + bool changeAssignToWeak(SourceLocation atLoc) { + SourceManager &SM = Pass.Ctx.getSourceManager(); + + // Break down the source location. + std::pair<FileID, unsigned> locInfo = SM.getDecomposedLoc(atLoc); + + // Try to load the file buffer. + bool invalidTemp = false; + llvm::StringRef file = SM.getBufferData(locInfo.first, &invalidTemp); + if (invalidTemp) + return true; + + const char *tokenBegin = file.data() + locInfo.second; + + // Lex from the start of the given location. + Lexer lexer(SM.getLocForStartOfFile(locInfo.first), + Pass.Ctx.getLangOptions(), + file.begin(), tokenBegin, file.end()); + Token tok; + lexer.LexFromRawLexer(tok); + if (tok.isNot(tok::at)) return true; + lexer.LexFromRawLexer(tok); + if (tok.isNot(tok::raw_identifier)) return true; + if (llvm::StringRef(tok.getRawIdentifierData(), tok.getLength()) + != "property") + return true; + lexer.LexFromRawLexer(tok); + if (tok.isNot(tok::l_paren)) return true; + + SourceLocation LParen = tok.getLocation(); + SourceLocation assignLoc; + bool isEmpty = false; + + lexer.LexFromRawLexer(tok); + if (tok.is(tok::r_paren)) { + isEmpty = true; + } else { + while (1) { + if (tok.isNot(tok::raw_identifier)) return true; + llvm::StringRef ident(tok.getRawIdentifierData(), tok.getLength()); + if (ident == "assign") + assignLoc = tok.getLocation(); + + do { + lexer.LexFromRawLexer(tok); + } while (tok.isNot(tok::comma) && tok.isNot(tok::r_paren)); + if (tok.is(tok::r_paren)) + break; + lexer.LexFromRawLexer(tok); + } + } + + Transaction Trans(Pass.TA); + if (assignLoc.isValid()) + Pass.TA.replaceText(assignLoc, "assign", "weak"); + else + Pass.TA.insertAfterToken(LParen, isEmpty ? "weak" : "weak, "); + return false; + } +}; + +class PropertiesChecker : public RecursiveASTVisitor<PropertiesChecker> { + MigrationPass &Pass; + +public: + PropertiesChecker(MigrationPass &pass) : Pass(pass) { } + + bool TraverseObjCImplementationDecl(ObjCImplementationDecl *D) { + AssignPropertiesTrans(Pass).doTransform(D); + return true; + } +}; + +} // anonymous namespace + +static void changeIvarsOfAssignProperties(MigrationPass &pass) { + PropertiesChecker(pass).TraverseDecl(pass.Ctx.getTranslationUnitDecl()); +} + +//===----------------------------------------------------------------------===// +// rewriteUnusedDelegateInit +//===----------------------------------------------------------------------===// + +namespace { + +class UnusedInitRewriter : public RecursiveASTVisitor<UnusedInitRewriter> { + Decl *Dcl; + Stmt *Body; + MigrationPass &Pass; + + llvm::DenseSet<Expr *> Removables; + +public: + UnusedInitRewriter(Decl *D, MigrationPass &pass) + : Dcl(D), Body(0), Pass(pass) { } + + void transformBody(Stmt *body) { + Body = body; + RemovablesCollector(Removables).TraverseStmt(body); + TraverseStmt(body); + } + + bool VisitObjCMessageExpr(ObjCMessageExpr *ME) { + if (ME->isDelegateInitCall() && + isRemovable(ME) && + Pass.TA.hasDiagnostic(diag::err_arc_unused_init_message, + ME->getExprLoc())) { + Transaction Trans(Pass.TA); + Pass.TA.clearDiagnostic(diag::err_arc_unused_init_message, + ME->getExprLoc()); + Pass.TA.insert(ME->getExprLoc(), "self = "); + } + return true; + } + +private: + bool isRemovable(Expr *E) const { + return Removables.count(E); + } +}; + +} // anonymous namespace + +static void rewriteUnusedDelegateInit(MigrationPass &pass) { + BodyTransform<UnusedInitRewriter> trans(pass); + trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl()); +} + +//===----------------------------------------------------------------------===// +// rewriteBlockObjCVariable +//===----------------------------------------------------------------------===// + +namespace { + +class RootBlockObjCVarRewriter : + public RecursiveASTVisitor<RootBlockObjCVarRewriter> { + MigrationPass &Pass; + llvm::DenseSet<VarDecl *> CheckedVars; + + class BlockVarChecker : public RecursiveASTVisitor<BlockVarChecker> { + VarDecl *Var; + + typedef RecursiveASTVisitor<BlockVarChecker> base; + public: + BlockVarChecker(VarDecl *var) : Var(var) { } + + bool TraverseImplicitCastExpr(ImplicitCastExpr *castE) { + if (BlockDeclRefExpr * + ref = dyn_cast<BlockDeclRefExpr>(castE->getSubExpr())) { + if (ref->getDecl() == Var) { + if (castE->getCastKind() == CK_LValueToRValue) + return true; // Using the value of the variable. + if (castE->getCastKind() == CK_NoOp && castE->isLValue() && + Var->getASTContext().getLangOptions().CPlusPlus) + return true; // Binding to const C++ reference. + } + } + + return base::TraverseImplicitCastExpr(castE); + } + + bool VisitBlockDeclRefExpr(BlockDeclRefExpr *E) { + if (E->getDecl() == Var) + return false; // The reference of the variable, and not just its value, + // is needed. + return true; + } + }; + +public: + RootBlockObjCVarRewriter(MigrationPass &pass) : Pass(pass) { } + + bool VisitBlockDecl(BlockDecl *block) { + llvm::SmallVector<VarDecl *, 4> BlockVars; + + for (BlockDecl::capture_iterator + I = block->capture_begin(), E = block->capture_end(); I != E; ++I) { + VarDecl *var = I->getVariable(); + if (I->isByRef() && + !isAlreadyChecked(var) && + var->getType()->isObjCObjectPointerType() && + isImplicitStrong(var->getType())) { + BlockVars.push_back(var); + } + } + + for (unsigned i = 0, e = BlockVars.size(); i != e; ++i) { + VarDecl *var = BlockVars[i]; + CheckedVars.insert(var); + + BlockVarChecker checker(var); + bool onlyValueOfVarIsNeeded = checker.TraverseStmt(block->getBody()); + if (onlyValueOfVarIsNeeded) { + BlocksAttr *attr = var->getAttr<BlocksAttr>(); + if(!attr) + continue; + bool hasARCRuntime = !Pass.Ctx.getLangOptions().ObjCNoAutoRefCountRuntime; + SourceManager &SM = Pass.Ctx.getSourceManager(); + Transaction Trans(Pass.TA); + Pass.TA.replaceText(SM.getInstantiationLoc(attr->getLocation()), + "__block", + hasARCRuntime ? "__weak" : "__unsafe_unretained"); + } + + } + + return true; + } + +private: + bool isAlreadyChecked(VarDecl *VD) { + return CheckedVars.count(VD); + } + + bool isImplicitStrong(QualType ty) { + if (isa<AttributedType>(ty.getTypePtr())) + return false; + return ty.getLocalQualifiers().getObjCLifetime() == Qualifiers::OCL_Strong; + } +}; + +class BlockObjCVarRewriter : public RecursiveASTVisitor<BlockObjCVarRewriter> { + MigrationPass &Pass; + +public: + BlockObjCVarRewriter(MigrationPass &pass) : Pass(pass) { } + + bool TraverseBlockDecl(BlockDecl *block) { + RootBlockObjCVarRewriter(Pass).TraverseDecl(block); + return true; + } +}; + +} // anonymous namespace + +static void rewriteBlockObjCVariable(MigrationPass &pass) { + BlockObjCVarRewriter trans(pass); + trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl()); +} + +//===----------------------------------------------------------------------===// +// removeZeroOutIvarsInDealloc +//===----------------------------------------------------------------------===// + +namespace { + +class ZeroOutInDeallocRemover : + public RecursiveASTVisitor<ZeroOutInDeallocRemover> { + typedef RecursiveASTVisitor<ZeroOutInDeallocRemover> base; + + MigrationPass &Pass; + + llvm::DenseMap<ObjCPropertyDecl*, ObjCPropertyImplDecl*> SynthesizedProperties; + ImplicitParamDecl *SelfD; + llvm::DenseSet<Expr *> Removables; + +public: + ZeroOutInDeallocRemover(MigrationPass &pass) : Pass(pass), SelfD(0) { } + + bool VisitObjCMessageExpr(ObjCMessageExpr *ME) { + ASTContext &Ctx = Pass.Ctx; + TransformActions &TA = Pass.TA; + + if (ME->getReceiverKind() != ObjCMessageExpr::Instance) + return true; + Expr *receiver = ME->getInstanceReceiver(); + if (!receiver) + return true; + + DeclRefExpr *refE = dyn_cast<DeclRefExpr>(receiver->IgnoreParenCasts()); + if (!refE || refE->getDecl() != SelfD) + return true; + + bool BackedBySynthesizeSetter = false; + for (llvm::DenseMap<ObjCPropertyDecl*, ObjCPropertyImplDecl*>::iterator + P = SynthesizedProperties.begin(), + E = SynthesizedProperties.end(); P != E; ++P) { + ObjCPropertyDecl *PropDecl = P->first; + if (PropDecl->getSetterName() == ME->getSelector()) { + BackedBySynthesizeSetter = true; + break; + } + } + if (!BackedBySynthesizeSetter) + return true; + + // Remove the setter message if RHS is null + Transaction Trans(TA); + Expr *RHS = ME->getArg(0); + bool RHSIsNull = + RHS->isNullPointerConstant(Ctx, + Expr::NPC_ValueDependentIsNull); + if (RHSIsNull && isRemovable(ME)) + TA.removeStmt(ME); + + return true; + } + + bool VisitBinaryOperator(BinaryOperator *BOE) { + if (isZeroingPropIvar(BOE) && isRemovable(BOE)) { + Transaction Trans(Pass.TA); + Pass.TA.removeStmt(BOE); + } + + return true; + } + + bool TraverseObjCMethodDecl(ObjCMethodDecl *D) { + if (D->getMethodFamily() != OMF_dealloc) + return true; + if (!D->hasBody()) + return true; + + ObjCImplDecl *IMD = dyn_cast<ObjCImplDecl>(D->getDeclContext()); + if (!IMD) + return true; + + SelfD = D->getSelfDecl(); + RemovablesCollector(Removables).TraverseStmt(D->getBody()); + + // For a 'dealloc' method use, find all property implementations in + // this class implementation. + for (ObjCImplDecl::propimpl_iterator + I = IMD->propimpl_begin(), EI = IMD->propimpl_end(); I != EI; ++I) { + ObjCPropertyImplDecl *PID = *I; + if (PID->getPropertyImplementation() == + ObjCPropertyImplDecl::Synthesize) { + ObjCPropertyDecl *PD = PID->getPropertyDecl(); + ObjCMethodDecl *setterM = PD->getSetterMethodDecl(); + if (!(setterM && setterM->isDefined())) { + ObjCPropertyDecl::PropertyAttributeKind AttrKind = + PD->getPropertyAttributes(); + if (AttrKind & + (ObjCPropertyDecl::OBJC_PR_retain | + ObjCPropertyDecl::OBJC_PR_copy | + ObjCPropertyDecl::OBJC_PR_strong)) + SynthesizedProperties[PD] = PID; + } + } + } + + // Now, remove all zeroing of ivars etc. + base::TraverseObjCMethodDecl(D); + + // clear out for next method. + SynthesizedProperties.clear(); + SelfD = 0; + Removables.clear(); + return true; + } + + bool TraverseFunctionDecl(FunctionDecl *D) { return true; } + bool TraverseBlockDecl(BlockDecl *block) { return true; } + bool TraverseBlockExpr(BlockExpr *block) { return true; } + +private: + bool isRemovable(Expr *E) const { + return Removables.count(E); + } + + bool isZeroingPropIvar(Expr *E) { + BinaryOperator *BOE = dyn_cast_or_null<BinaryOperator>(E); + if (!BOE) return false; + + if (BOE->getOpcode() == BO_Comma) + return isZeroingPropIvar(BOE->getLHS()) && + isZeroingPropIvar(BOE->getRHS()); + + if (BOE->getOpcode() != BO_Assign) + return false; + + ASTContext &Ctx = Pass.Ctx; + + Expr *LHS = BOE->getLHS(); + if (ObjCIvarRefExpr *IV = dyn_cast<ObjCIvarRefExpr>(LHS)) { + ObjCIvarDecl *IVDecl = IV->getDecl(); + if (!IVDecl->getType()->isObjCObjectPointerType()) + return false; + bool IvarBacksPropertySynthesis = false; + for (llvm::DenseMap<ObjCPropertyDecl*, ObjCPropertyImplDecl*>::iterator + P = SynthesizedProperties.begin(), + E = SynthesizedProperties.end(); P != E; ++P) { + ObjCPropertyImplDecl *PropImpDecl = P->second; + if (PropImpDecl && PropImpDecl->getPropertyIvarDecl() == IVDecl) { + IvarBacksPropertySynthesis = true; + break; + } + } + if (!IvarBacksPropertySynthesis) + return false; + } + else if (ObjCPropertyRefExpr *PropRefExp = dyn_cast<ObjCPropertyRefExpr>(LHS)) { + // TODO: Using implicit property decl. + if (PropRefExp->isImplicitProperty()) + return false; + if (ObjCPropertyDecl *PDecl = PropRefExp->getExplicitProperty()) { + if (!SynthesizedProperties.count(PDecl)) + return false; + } + } + else + return false; + + Expr *RHS = BOE->getRHS(); + bool RHSIsNull = RHS->isNullPointerConstant(Ctx, + Expr::NPC_ValueDependentIsNull); + if (RHSIsNull) + return true; + + return isZeroingPropIvar(RHS); + } +}; + +} // anonymous namespace + +static void removeZeroOutIvarsInDealloc(MigrationPass &pass) { + ZeroOutInDeallocRemover trans(pass); + trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl()); +} + +//===----------------------------------------------------------------------===// +// getAllTransformations. +//===----------------------------------------------------------------------===// + +static void independentTransforms(MigrationPass &pass) { + rewriteAutoreleasePool(pass); + changeIvarsOfAssignProperties(pass); + removeRetainReleaseDealloc(pass); + rewriteUnusedDelegateInit(pass); + removeZeroOutIvarsInDealloc(pass); + makeAssignARCSafe(pass); + castNonObjCToObjC(pass); + rewriteBlockObjCVariable(pass); + rewriteAllocCopyWithZone(pass); +} + +std::vector<TransformFn> arcmt::getAllTransformations() { + std::vector<TransformFn> transforms; + + // This must come first since rewriteAutoreleasePool depends on -release + // calls being present to determine the @autorelease ending scope. + transforms.push_back(independentTransforms); + + transforms.push_back(removeEmptyStatements); + transforms.push_back(removeDeallocMethod); + + return transforms; +} |