[CodeGen] Look at the type of a block capture field rather than the type

of the captured variable when determining whether the capture needs
special handing when the block is copied or disposed.

This fixes bugs in the handling of variables captured by a block that is
nested inside a lambda that captures the variables by reference.

rdar://problem/43540889

Differential Revision: https://reviews.llvm.org/D51025

llvm-svn: 340408

1 files changed, 82 insertions, 0 deletions

diff --git a/clang/test/CodeGenObjCXX/block-nested-in-lambda.mm b/clang/test/CodeGenObjCXX/block-nested-in-lambda.mm
new file mode 100644
index 00000000000..a538d1bd2b1
--- /dev/null
+++ b/clang/test/CodeGenObjCXX/block-nested-in-lambda.mm
@@ -0,0 +1,82 @@
+// RUN: %clang_cc1 -triple=x86_64-apple-darwin10 -emit-llvm -std=c++11 -fblocks -fobjc-arc -o - %s | FileCheck %s
+
+// CHECK: %[[STRUCT_BLOCK_DESCRIPTOR:.*]] = type { i64, i64 }
+
+// CHECK: %[[BLOCK_CAPTURED0:.*]] = getelementptr inbounds <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, i32*, i32* }>, <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, i32*, i32* }>* %[[BLOCK:.*]], i32 0, i32 5
+// CHECK: %[[V0:.*]] = getelementptr inbounds %[[LAMBDA_CLASS:.*]], %[[LAMBDA_CLASS]]* %[[THIS:.*]], i32 0, i32 0
+// CHECK: %[[V1:.*]] = load i32*, i32** %[[V0]], align 8
+// CHECK: store i32* %[[V1]], i32** %[[BLOCK_CAPTURED0]], align 8
+// CHECK: %[[BLOCK_CAPTURED1:.*]] = getelementptr inbounds <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, i32*, i32* }>, <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, i32*, i32* }>* %[[BLOCK]], i32 0, i32 6
+// CHECK: %[[V2:.*]] = getelementptr inbounds %[[LAMBDA_CLASS]], %[[LAMBDA_CLASS]]* %[[THIS]], i32 0, i32 1
+// CHECK: %[[V3:.*]] = load i32*, i32** %[[V2]], align 8
+// CHECK: store i32* %[[V3]], i32** %[[BLOCK_CAPTURED1]], align 8
+
+void foo1(int &, int &);
+
+void block_in_lambda(int &s1, int &s2) {
+  auto lambda = [&s1, &s2]() {
+    auto block = ^{
+      foo1(s1, s2);
+    };
+    block();
+  };
+
+  lambda();
+}
+
+namespace CaptureByReference {
+
+id getObj();
+void use(id);
+
+// Block copy/dispose helpers aren't needed because 'a' is captured by
+// reference.
+
+// CHECK-LABEL: define void @_ZN18CaptureByReference5test0Ev(
+// CHECK-LABEL: define internal void @"_ZZN18CaptureByReference5test0EvENK3$_1clEv"(
+// CHECK: %[[BLOCK_DESCRIPTOR:.*]] = getelementptr inbounds <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8** }>, <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8** }>* %{{.*}}, i32 0, i32 4
+// CHECK: store %[[STRUCT_BLOCK_DESCRIPTOR]]* bitcast ({ i64, i64, i8*, i64 }* @"__block_descriptor_40_e5_v8@?0ls32l8" to %[[STRUCT_BLOCK_DESCRIPTOR]]*), %[[STRUCT_BLOCK_DESCRIPTOR]]** %[[BLOCK_DESCRIPTOR]], align 8
+
+void test0() {
+  id a = getObj();
+  [&]{ ^{ a = 0; }(); }();
+}
+
+// Block copy/dispose helpers shouldn't have to retain/release 'a' because it
+// is captured by reference.
+
+// CHECK-LABEL: define void @_ZN18CaptureByReference5test1Ev(
+// CHECK-LABEL: define internal void @"_ZZN18CaptureByReference5test1EvENK3$_2clEv"(
+// CHECK: %[[BLOCK_DESCRIPTOR:.*]] = getelementptr inbounds <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8*, i8** }>, <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8*, i8** }>* %{{.*}}, i32 0, i32 4
+// CHECK: store %[[STRUCT_BLOCK_DESCRIPTOR]]* bitcast ({ i64, i64, i8*, i8*, i8*, i64 }* @"__block_descriptor_56_8_32s40s_e5_v8@?0l" to %[[STRUCT_BLOCK_DESCRIPTOR]]*), %[[STRUCT_BLOCK_DESCRIPTOR]]** %[[BLOCK_DESCRIPTOR]], align 8
+
+// CHECK-LABEL: define linkonce_odr hidden void @__copy_helper_block_8_32s40s(
+// CHECK-NOT: call void @objc_storeStrong(
+// CHECK: %[[V4:.*]] = getelementptr inbounds <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8*, i8** }>, <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8*, i8** }>* %{{.*}}, i32 0, i32 5
+// CHECK: %[[V5:.*]] = getelementptr inbounds <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8*, i8** }>, <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8*, i8** }>* %{{.*}}, i32 0, i32 5
+// CHECK: %[[BLOCKCOPY_SRC:.*]] = load i8*, i8** %[[V4]], align 8
+// CHECK: store i8* null, i8** %[[V5]], align 8
+// CHECK: call void @objc_storeStrong(i8** %[[V5]], i8* %[[BLOCKCOPY_SRC]])
+// CHECK: %[[V6:.*]] = getelementptr inbounds <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8*, i8** }>, <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8*, i8** }>* %{{.*}}, i32 0, i32 6
+// CHECK: %[[V7:.*]] = getelementptr inbounds <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8*, i8** }>, <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8*, i8** }>* %{{.*}}, i32 0, i32 6
+// CHECK: %[[BLOCKCOPY_SRC2:.*]] = load i8*, i8** %[[V6]], align 8
+// CHECK: store i8* null, i8** %[[V7]], align 8
+// CHECK: call void @objc_storeStrong(i8** %[[V7]], i8* %[[BLOCKCOPY_SRC2]])
+// CHECK-NOT: call void @objc_storeStrong(
+// CHECK: ret void
+
+// CHECK-LABEL: define linkonce_odr hidden void @__destroy_helper_block_8_32s40s(
+// CHECK: %[[V2:.*]] = getelementptr inbounds <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8*, i8** }>, <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8*, i8** }>* %{{.*}}, i32 0, i32 5
+// CHECK: %[[V3:.*]] = getelementptr inbounds <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8*, i8** }>, <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8*, i8** }>* %{{.*}}, i32 0, i32 6
+// CHECK-NOT: call void @objc_storeStrong(
+// CHECK: call void @objc_storeStrong(i8** %[[V3]], i8* null)
+// CHECK: call void @objc_storeStrong(i8** %[[V2]], i8* null)
+// CHECK-NOT: call void @objc_storeStrong(
+// CHECK: ret void
+
+void test1() {
+  id a = getObj(), b = getObj(), c = getObj();
+  [&a, b, c]{ ^{ a = 0; use(b); use(c); }(); }();
+}
+
+}