From 428edb7f7599b4ee44eaad00bb3c330495fc1ad6 Mon Sep 17 00:00:00 2001 From: Fariborz Jahanian Date: Tue, 16 Apr 2013 15:25:39 +0000 Subject: [PATCH] Objective-C IRGen. Use llvm::WeakVH for caching couple of global symbols used for generation of CF/NS string meta-data so they are not released prematuely in certain corner cases. // rdar:// 13598026. Reviewed by John M. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179599 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/CodeGenModule.cpp | 25 ++++++----- lib/CodeGen/CodeGenModule.h | 4 +- test/CodeGenObjC/tentative-cfconstantstring.m | 44 +++++++++++++++++++ 3 files changed, 61 insertions(+), 12 deletions(-) create mode 100644 test/CodeGenObjC/tentative-cfconstantstring.m diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp index f8627b2b70..5893814d7a 100644 --- a/lib/CodeGen/CodeGenModule.cpp +++ b/lib/CodeGen/CodeGenModule.cpp @@ -2279,7 +2279,8 @@ CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) { llvm::Constant *Zero = llvm::Constant::getNullValue(Int32Ty); llvm::Constant *Zeros[] = { Zero, Zero }; - + llvm::Value *V; + // If we don't already have it, get __CFConstantStringClassReference. if (!CFConstantStringClassRef) { llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy); @@ -2287,9 +2288,11 @@ CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) { llvm::Constant *GV = CreateRuntimeVariable(Ty, "__CFConstantStringClassReference"); // Decay array -> ptr - CFConstantStringClassRef = - llvm::ConstantExpr::getGetElementPtr(GV, Zeros); + V = llvm::ConstantExpr::getGetElementPtr(GV, Zeros); + CFConstantStringClassRef = V; } + else + V = CFConstantStringClassRef; QualType CFTy = getContext().getCFConstantStringType(); @@ -2299,7 +2302,7 @@ CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) { llvm::Constant *Fields[4]; // Class pointer. - Fields[0] = CFConstantStringClassRef; + Fields[0] = cast(V); // Flags. llvm::Type *Ty = getTypes().ConvertType(getContext().UnsignedIntTy); @@ -2386,7 +2389,7 @@ CodeGenModule::GetAddrOfConstantString(const StringLiteral *Literal) { llvm::Constant *Zero = llvm::Constant::getNullValue(Int32Ty); llvm::Constant *Zeros[] = { Zero, Zero }; - + llvm::Value *V; // If we don't already have it, get _NSConstantStringClassReference. if (!ConstantStringClassRef) { std::string StringClass(getLangOpts().ObjCConstantStringClass); @@ -2399,8 +2402,8 @@ CodeGenModule::GetAddrOfConstantString(const StringLiteral *Literal) { GV = getObjCRuntime().GetClassGlobal(str); // Make sure the result is of the correct type. llvm::Type *PTy = llvm::PointerType::getUnqual(Ty); - ConstantStringClassRef = - llvm::ConstantExpr::getBitCast(GV, PTy); + V = llvm::ConstantExpr::getBitCast(GV, PTy); + ConstantStringClassRef = V; } else { std::string str = StringClass.empty() ? "_NSConstantStringClassReference" @@ -2408,10 +2411,12 @@ CodeGenModule::GetAddrOfConstantString(const StringLiteral *Literal) { llvm::Type *PTy = llvm::ArrayType::get(Ty, 0); GV = CreateRuntimeVariable(PTy, str); // Decay array -> ptr - ConstantStringClassRef = - llvm::ConstantExpr::getGetElementPtr(GV, Zeros); + V = llvm::ConstantExpr::getGetElementPtr(GV, Zeros); + ConstantStringClassRef = V; } } + else + V = ConstantStringClassRef; if (!NSConstantStringType) { // Construct the type for a constant NSString. @@ -2450,7 +2455,7 @@ CodeGenModule::GetAddrOfConstantString(const StringLiteral *Literal) { llvm::Constant *Fields[3]; // Class pointer. - Fields[0] = ConstantStringClassRef; + Fields[0] = cast(V); // String pointer. llvm::Constant *C = diff --git a/lib/CodeGen/CodeGenModule.h b/lib/CodeGen/CodeGenModule.h index 1eb0ebb624..ab499ae9b4 100644 --- a/lib/CodeGen/CodeGenModule.h +++ b/lib/CodeGen/CodeGenModule.h @@ -346,11 +346,11 @@ class CodeGenModule : public CodeGenTypeCache { /// CFConstantStringClassRef - Cached reference to the class for constant /// strings. This value has type int * but is actually an Obj-C class pointer. - llvm::Constant *CFConstantStringClassRef; + llvm::WeakVH CFConstantStringClassRef; /// ConstantStringClassRef - Cached reference to the class for constant /// strings. This value has type int * but is actually an Obj-C class pointer. - llvm::Constant *ConstantStringClassRef; + llvm::WeakVH ConstantStringClassRef; /// \brief The LLVM type corresponding to NSConstantString. llvm::StructType *NSConstantStringType; diff --git a/test/CodeGenObjC/tentative-cfconstantstring.m b/test/CodeGenObjC/tentative-cfconstantstring.m new file mode 100644 index 0000000000..c0bea0f2eb --- /dev/null +++ b/test/CodeGenObjC/tentative-cfconstantstring.m @@ -0,0 +1,44 @@ +// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -emit-llvm -o - %s | FileCheck %s +// rdar://13598026 + +@interface NSObject @end + +@class NSString; + +int __CFConstantStringClassReference[24]; + +@interface Bar : NSObject ++(void)format:(NSString *)format,...; +@end + +@interface Foo : NSObject +@end + + +static inline void _inlineFunction() { + [Bar format:@" "]; +} + +@implementation Foo + + ++(NSString *)someMethod { + return @""; +} + +-(void)someMethod { + _inlineFunction(); +} +@end + +// CHECK: @__CFConstantStringClassReference = common global [24 x i32] zeroinitializer, align 16 +// CHECK: @_unnamed_cfstring_{{.*}} = private constant %struct.NSConstantString { i32* getelementptr inbounds ([24 x i32]* @__CFConstantStringClassReference, i32 0, i32 0) + +// CHECK: define internal void @_inlineFunction() +// CHECK-NEXT: entry: +// CHECK-NEXT: [[ZERO:%.*]] = load %struct._class_t** @"\01L_OBJC_CLASSLIST_REFERENCES_ +// CHECK-NEXT: [[ONE:%.*]] = load i8** @"\01L_OBJC_SELECTOR_REFERENCES_" +// CHECK-NEXT: [[TWO:%.*]] = bitcast %struct._class_t* [[ZERO]] to i8* +// CHECK-NEXT: call{{.*}}@objc_msgSend{{.*}}(i8* [[TWO]], i8* [[ONE]], [[ZERO]]* bitcast (%struct.NSConstantString* @_unnamed_cfstring_{{.*}} +// CHECK-NEXT: ret void + -- 2.40.0