[CodeGen][ObjC] Build the global block structure before emitting the
body of global block invoke functions.
This commit fixes an infinite loop in IRGen that occurs when compiling
the following code:
void FUNC2() {
static void (^const block1)(int) = ^(int a){
if (a--)
block1(a);
};
}
This is how IRGen gets stuck in the infinite loop:
1. GenerateBlockFunction is called to emit the body of "block1".
2. GetAddrOfGlobalBlock is called to get the address of "block1". The
function calls getAddrOfGlobalBlockIfEmitted to check whether the
global block has been emitted. If it hasn't been emitted, it then
tries to emit the body of the block function by calling
GenerateBlockFunction, which goes back to step 1.
This commit prevents the inifinite loop by building the global block in
GenerateBlockFunction before emitting the body of the block function.
rdar://problem/34541684
Differential Revision: https://reviews.llvm.org/D38118
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@314029 91177308-0d34-0410-b5e6-96231b3b80d8
(cherry picked from commit a3394c6dfe197d84e74eae9cc8b77dc4356cff54)
diff --git a/lib/CodeGen/CGBlocks.cpp b/lib/CodeGen/CGBlocks.cpp
index 372d23c..ffc2b08 100644
--- a/lib/CodeGen/CGBlocks.cpp
+++ b/lib/CodeGen/CGBlocks.cpp
@@ -714,12 +714,13 @@
llvm::Constant *blockFn
= CodeGenFunction(CGM, true).GenerateBlockFunction(CurGD, blockInfo,
LocalDeclMap,
- isLambdaConv);
+ isLambdaConv,
+ blockInfo.CanBeGlobal);
blockFn = llvm::ConstantExpr::getBitCast(blockFn, VoidPtrTy);
// If there is nothing to capture, we can emit this as a global block.
if (blockInfo.CanBeGlobal)
- return buildGlobalBlock(CGM, blockInfo, blockFn);
+ return CGM.getAddrOfGlobalBlockIfEmitted(blockInfo.BlockExpression);
// Otherwise, we have to emit this as a local block.
@@ -1074,17 +1075,14 @@
computeBlockInfo(*this, nullptr, blockInfo);
// Using that metadata, generate the actual block function.
- llvm::Constant *blockFn;
{
CodeGenFunction::DeclMapTy LocalDeclMap;
- blockFn = CodeGenFunction(*this).GenerateBlockFunction(GlobalDecl(),
- blockInfo,
- LocalDeclMap,
- false);
+ CodeGenFunction(*this).GenerateBlockFunction(
+ GlobalDecl(), blockInfo, LocalDeclMap,
+ /*IsLambdaConversionToBlock*/ false, /*BuildGlobalBlock*/ true);
}
- blockFn = llvm::ConstantExpr::getBitCast(blockFn, VoidPtrTy);
- return buildGlobalBlock(*this, blockInfo, blockFn);
+ return getAddrOfGlobalBlockIfEmitted(BE);
}
static llvm::Constant *buildGlobalBlock(CodeGenModule &CGM,
@@ -1175,7 +1173,8 @@
CodeGenFunction::GenerateBlockFunction(GlobalDecl GD,
const CGBlockInfo &blockInfo,
const DeclMapTy &ldm,
- bool IsLambdaConversionToBlock) {
+ bool IsLambdaConversionToBlock,
+ bool BuildGlobalBlock) {
const BlockDecl *blockDecl = blockInfo.getBlockDecl();
CurGD = GD;
@@ -1224,6 +1223,10 @@
fnLLVMType, llvm::GlobalValue::InternalLinkage, name, &CGM.getModule());
CGM.SetInternalFunctionAttributes(blockDecl, fn, fnInfo);
+ if (BuildGlobalBlock)
+ buildGlobalBlock(CGM, blockInfo,
+ llvm::ConstantExpr::getBitCast(fn, VoidPtrTy));
+
// Begin generating the function.
StartFunction(blockDecl, fnType->getReturnType(), fn, fnInfo, args,
blockDecl->getLocation(),
diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index 6df54f0..4f7c0fa 100644
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -1565,7 +1565,8 @@
llvm::Function *GenerateBlockFunction(GlobalDecl GD,
const CGBlockInfo &Info,
const DeclMapTy &ldm,
- bool IsLambdaConversionToBlock);
+ bool IsLambdaConversionToBlock,
+ bool BuildGlobalBlock);
llvm::Constant *GenerateCopyHelperFunction(const CGBlockInfo &blockInfo);
llvm::Constant *GenerateDestroyHelperFunction(const CGBlockInfo &blockInfo);
diff --git a/test/CodeGen/mangle-blocks.c b/test/CodeGen/mangle-blocks.c
index e8de92d..4ea5a55 100644
--- a/test/CodeGen/mangle-blocks.c
+++ b/test/CodeGen/mangle-blocks.c
@@ -12,12 +12,12 @@
}
// CHECK: @__func__.__mangle_block_invoke_2 = private unnamed_addr constant [22 x i8] c"mangle_block_invoke_2\00", align 1
-// CHECK: @.str = private unnamed_addr constant {{.*}}, align 1
-// CHECK: @.str.1 = private unnamed_addr constant [7 x i8] c"mangle\00", align 1
+// CHECK: @.str{{.*}} = private unnamed_addr constant {{.*}}, align 1
+// CHECK: @.str[[STR1:.*]] = private unnamed_addr constant [7 x i8] c"mangle\00", align 1
// CHECK: define internal void @__mangle_block_invoke(i8* %.block_descriptor)
// CHECK: define internal void @__mangle_block_invoke_2(i8* %.block_descriptor){{.*}}{
-// CHECK: call void @__assert_rtn(i8* getelementptr inbounds ([22 x i8], [22 x i8]* @__func__.__mangle_block_invoke_2, i32 0, i32 0), i8* getelementptr inbounds {{.*}}, i32 9, i8* getelementptr inbounds ([7 x i8], [7 x i8]* @.str.1, i32 0, i32 0))
+// CHECK: call void @__assert_rtn(i8* getelementptr inbounds ([22 x i8], [22 x i8]* @__func__.__mangle_block_invoke_2, i32 0, i32 0), i8* getelementptr inbounds {{.*}}, i32 9, i8* getelementptr inbounds ([7 x i8], [7 x i8]* @.str[[STR1]], i32 0, i32 0))
// CHECK: }
diff --git a/test/CodeGenObjC/local-static-block.m b/test/CodeGenObjC/local-static-block.m
index 73c670f..67ede63 100644
--- a/test/CodeGenObjC/local-static-block.m
+++ b/test/CodeGenObjC/local-static-block.m
@@ -46,6 +46,17 @@
}
}
+void FUNC2() {
+ static void (^const block1)(int) = ^(int a){
+ if (a--)
+ block1(a);
+ };
+}
+
+// CHECK-LABEL-LP64: define void @FUNC2(
+// CHECK: define internal void @_block_invoke{{.*}}(
+// CHECK: call void %{{.*}}(i8* bitcast ({ i8**, i32, i32, i8*, %struct.__block_descriptor* }* @__block_literal_global{{.*}} to i8*), i32 %{{.*}})
+
void FUNC1()
{
static NSArray *(^ArrayRecurs)(NSArray *addresses, unsigned long level) = ^(NSArray *addresses, unsigned long level) {
diff --git a/test/CodeGenObjC/mangle-blocks.m b/test/CodeGenObjC/mangle-blocks.m
index 4cc3204..73522cd 100644
--- a/test/CodeGenObjC/mangle-blocks.m
+++ b/test/CodeGenObjC/mangle-blocks.m
@@ -18,11 +18,11 @@
@end
// CHECK: @"__func__.__14-[Test mangle]_block_invoke_2" = private unnamed_addr constant [30 x i8] c"-[Test mangle]_block_invoke_2\00", align 1
-// CHECK: @.str = private unnamed_addr constant {{.*}}, align 1
-// CHECK: @.str.1 = private unnamed_addr constant [7 x i8] c"mangle\00", align 1
+// CHECK: @.str{{.*}} = private unnamed_addr constant {{.*}}, align 1
+// CHECK: @.str[[STR1:.*]] = private unnamed_addr constant [7 x i8] c"mangle\00", align 1
// CHECK: define internal void @"__14-[Test mangle]_block_invoke"(i8* %.block_descriptor)
// CHECK: define internal void @"__14-[Test mangle]_block_invoke_2"(i8* %.block_descriptor){{.*}}{
-// CHECK: call void @__assert_rtn(i8* getelementptr inbounds ([30 x i8], [30 x i8]* @"__func__.__14-[Test mangle]_block_invoke_2", i32 0, i32 0), i8* getelementptr inbounds {{.*}}, i32 14, i8* getelementptr inbounds ([7 x i8], [7 x i8]* @.str.1, i32 0, i32 0))
+// CHECK: call void @__assert_rtn(i8* getelementptr inbounds ([30 x i8], [30 x i8]* @"__func__.__14-[Test mangle]_block_invoke_2", i32 0, i32 0), i8* getelementptr inbounds {{.*}}, i32 14, i8* getelementptr inbounds ([7 x i8], [7 x i8]* @.str[[STR1]], i32 0, i32 0))
// CHECK: }
