The ARC Migration Tool. All the credit goes to Argyrios and Fariborz
for this.
llvm-svn: 133104
diff --git a/clang/lib/ARCMigrate/Transforms.cpp b/clang/lib/ARCMigrate/Transforms.cpp
new file mode 100644
index 0000000..ab3bc1d
--- /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;
+}