Author: ahatanak Date: Sat Apr 15 01:42:00 2017 New Revision: 300396 URL: http://llvm.org/viewvc/llvm-project?rev=300396&view=rev Log: [ObjC] Use empty Objective-C collection literal constants when available.
Original patch by Douglas Gregor with minor modifications. This recommits r300389, which broke bots because there have been API changes since the original patch was written. rdar://problem/20689633 Added: cfe/trunk/test/CodeGenObjC/empty-collection-literals.m Modified: cfe/trunk/include/clang/Basic/ObjCRuntime.h cfe/trunk/lib/CodeGen/CGObjC.cpp cfe/trunk/lib/Sema/SemaExprCXX.cpp Modified: cfe/trunk/include/clang/Basic/ObjCRuntime.h URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/ObjCRuntime.h?rev=300396&r1=300395&r2=300396&view=diff ============================================================================== --- cfe/trunk/include/clang/Basic/ObjCRuntime.h (original) +++ cfe/trunk/include/clang/Basic/ObjCRuntime.h Sat Apr 15 01:42:00 2017 @@ -326,6 +326,20 @@ public: } } + /// Are the empty collection symbols available? + bool hasEmptyCollections() const { + switch (getKind()) { + default: + return false; + case MacOSX: + return getVersion() >= VersionTuple(10, 11); + case iOS: + return getVersion() >= VersionTuple(9); + case WatchOS: + return getVersion() >= VersionTuple(2); + } + } + /// \brief Try to parse an Objective-C runtime specification from the given /// string. /// Modified: cfe/trunk/lib/CodeGen/CGObjC.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGObjC.cpp?rev=300396&r1=300395&r2=300396&view=diff ============================================================================== --- cfe/trunk/lib/CodeGen/CGObjC.cpp (original) +++ cfe/trunk/lib/CodeGen/CGObjC.cpp Sat Apr 15 01:42:00 2017 @@ -117,10 +117,22 @@ llvm::Value *CodeGenFunction::EmitObjCCo const ObjCArrayLiteral *ALE = dyn_cast<ObjCArrayLiteral>(E); if (!ALE) DLE = cast<ObjCDictionaryLiteral>(E); - - // Compute the type of the array we're initializing. + + // Optimize empty collections by referencing constants, when available. uint64_t NumElements = ALE ? ALE->getNumElements() : DLE->getNumElements(); + if (NumElements == 0 && CGM.getLangOpts().ObjCRuntime.hasEmptyCollections()) { + StringRef ConstantName = ALE ? "__NSArray0__" : "__NSDictionary0__"; + QualType IdTy(CGM.getContext().getObjCIdType()); + llvm::Constant *Constant = + CGM.CreateRuntimeVariable(ConvertType(IdTy), ConstantName); + Address Addr(Constant, Context.getTypeAlignInChars(IdTy)); + LValue LV = MakeAddrLValue(Addr, IdTy); + return Builder.CreateBitCast(EmitLoadOfScalar(LV, E->getLocStart()), + ConvertType(E->getType())); + } + + // Compute the type of the array we're initializing. llvm::APInt APNumElements(Context.getTypeSize(Context.getSizeType()), NumElements); QualType ElementType = Context.getObjCIdType().withConst(); Modified: cfe/trunk/lib/Sema/SemaExprCXX.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaExprCXX.cpp?rev=300396&r1=300395&r2=300396&view=diff ============================================================================== --- cfe/trunk/lib/Sema/SemaExprCXX.cpp (original) +++ cfe/trunk/lib/Sema/SemaExprCXX.cpp Sat Apr 15 01:42:00 2017 @@ -5980,9 +5980,21 @@ ExprResult Sema::MaybeBindToTemporary(Ex } else if (ObjCBoxedExpr *BoxedExpr = dyn_cast<ObjCBoxedExpr>(E)) { D = BoxedExpr->getBoxingMethod(); } else if (ObjCArrayLiteral *ArrayLit = dyn_cast<ObjCArrayLiteral>(E)) { + // Don't do reclaims if we're using the zero-element array + // constant. + if (ArrayLit->getNumElements() == 0 && + Context.getLangOpts().ObjCRuntime.hasEmptyCollections()) + return E; + D = ArrayLit->getArrayWithObjectsMethod(); } else if (ObjCDictionaryLiteral *DictLit = dyn_cast<ObjCDictionaryLiteral>(E)) { + // Don't do reclaims if we're using the zero-element dictionary + // constant. + if (DictLit->getNumElements() == 0 && + Context.getLangOpts().ObjCRuntime.hasEmptyCollections()) + return E; + D = DictLit->getDictWithObjectsMethod(); } Added: cfe/trunk/test/CodeGenObjC/empty-collection-literals.m URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenObjC/empty-collection-literals.m?rev=300396&view=auto ============================================================================== --- cfe/trunk/test/CodeGenObjC/empty-collection-literals.m (added) +++ cfe/trunk/test/CodeGenObjC/empty-collection-literals.m Sat Apr 15 01:42:00 2017 @@ -0,0 +1,51 @@ +// RUN: %clang_cc1 -I %S/Inputs -triple x86_64-apple-macosx10.10.0 -fobjc-runtime=macosx-10.10.0 -emit-llvm -fblocks -fobjc-arc -fobjc-runtime-has-weak -o - %s | FileCheck -check-prefix=CHECK-WITHOUT-EMPTY-COLLECTIONS %s +// RUN: %clang_cc1 -I %S/Inputs -triple x86_64-apple-macosx10.11.0 -fobjc-runtime=macosx-10.11.0 -emit-llvm -fblocks -fobjc-arc -fobjc-runtime-has-weak -o - %s | FileCheck -check-prefix=CHECK-WITH-EMPTY-COLLECTIONS %s + +// RUN: %clang_cc1 -I %S/Inputs -triple arm64-apple-ios8.0 -fobjc-runtime=ios-8.0 -emit-llvm -fblocks -fobjc-arc -fobjc-runtime-has-weak -o - %s | FileCheck -check-prefix=CHECK-WITHOUT-EMPTY-COLLECTIONS %s +// RUN: %clang_cc1 -I %S/Inputs -triple arm64-apple-ios9.0 -fobjc-runtime=ios-9.0 -emit-llvm -fblocks -fobjc-arc -fobjc-runtime-has-weak -o - %s | FileCheck -check-prefix=CHECK-WITH-EMPTY-COLLECTIONS %s + +// RUN: %clang_cc1 -I %S/Inputs -triple armv7k-apple-watchos2.0 -fobjc-runtime=watchos-1.0 -emit-llvm -fblocks -fobjc-arc -fobjc-runtime-has-weak -o - %s | FileCheck -check-prefix=CHECK-WITHOUT-EMPTY-COLLECTIONS %s +// RUN: %clang_cc1 -I %S/Inputs -triple armv7k-apple-watchos2.0 -fobjc-runtime=watchos-2.0 -emit-llvm -fblocks -fobjc-arc -fobjc-runtime-has-weak -o - %s | FileCheck -check-prefix=CHECK-WITH-EMPTY-COLLECTIONS %s + +// RUN: %clang_cc1 -I %S/Inputs -triple arm64-apple-tvos8.0 -fobjc-runtime=ios-8.0 -emit-llvm -fblocks -fobjc-arc -fobjc-runtime-has-weak -o - %s | FileCheck -check-prefix=CHECK-WITHOUT-EMPTY-COLLECTIONS %s +// RUN: %clang_cc1 -I %S/Inputs -triple arm64-apple-tvos9.0 -fobjc-runtime=ios-9.0 -emit-llvm -fblocks -fobjc-arc -fobjc-runtime-has-weak -o - %s | FileCheck -check-prefix=CHECK-WITH-EMPTY-COLLECTIONS %s + +#include "literal-support.h" + +void test_empty_array() { + // CHECK-WITHOUT-EMPTY-COLLECTIONS-LABEL: define void @test_empty_array + // CHECK-WITHOUT-EMPTY-COLLECTIONS-NOT: ret void + // CHECK-WITHOUT-EMPTY-COLLECTIONS: {{call.*objc_msgSend}} + // CHECK-WITHOUT-EMPTY-COLLECTIONS-NOT: ret void + // CHECK-WITHOUT-EMPTY-COLLECTIONS: {{call.*objc_retainAutoreleasedReturnValue}} + // CHECK-WITHOUT-EMPTY-COLLECTIONS: ret void + + // CHECK-WITH-EMPTY-COLLECTIONS-LABEL: define void @test_empty_array + // CHECK-WITH-EMPTY-COLLECTIONS-NOT: ret void + // CHECK-WITH-EMPTY-COLLECTIONS: load {{.*}} @__NSArray0__ + // CHECK-WITH-EMPTY-COLLECTIONS-NOT: ret void + // CHECK-WITH-EMPTY-COLLECTIONS: {{call.*objc_retain\(}} + // CHECK-WITH-EMPTY-COLLECTIONS-NOT: ret void + // CHECK-WITH-EMPTY-COLLECTIONS: call void @objc_storeStrong + // CHECK-WITH-EMPTY-COLLECTIONS-NEXT: ret void + NSArray *arr = @[]; +} + +void test_empty_dictionary() { + // CHECK-WITHOUT-EMPTY-COLLECTIONS-LABEL: define void @test_empty_dictionary + // CHECK-WITHOUT-EMPTY-COLLECTIONS-NOT: ret void + // CHECK-WITHOUT-EMPTY-COLLECTIONS: {{call.*objc_msgSend}} + // CHECK-WITHOUT-EMPTY-COLLECTIONS-NOT: ret void + // CHECK-WITHOUT-EMPTY-COLLECTIONS: {{call.*objc_retainAutoreleasedReturnValue}} + // CHECK-WITHOUT-EMPTY-COLLECTIONS: ret void + + // CHECK-WITH-EMPTY-COLLECTIONS-LABEL: define void @test_empty_dictionary + // CHECK-WITH-EMPTY-COLLECTIONS-NOT: ret void + // CHECK-WITH-EMPTY-COLLECTIONS: load {{.*}} @__NSDictionary0__ + // CHECK-WITH-EMPTY-COLLECTIONS-NOT: ret void + // CHECK-WITH-EMPTY-COLLECTIONS: {{call.*objc_retain\(}} + // CHECK-WITH-EMPTY-COLLECTIONS-NOT: ret void + // CHECK-WITH-EMPTY-COLLECTIONS: call void @objc_storeStrong + // CHECK-WITH-EMPTY-COLLECTIONS-NEXT: ret void + NSDictionary *dict = @{}; +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits