Add missing temporary materialization conversion on left-hand side of .

in some member function calls.

Specifically, when calling a conversion function, we would fail to
create the AST node representing materialization of the class object.

llvm-svn: 338135

1 files changed, 27 insertions, 9 deletions

diff --git a/clang/test/CodeGenCXX/stack-reuse-miscompile.cpp b/clang/test/CodeGenCXX/stack-reuse-miscompile.cpp
index 3b860a57395..4e824d94f51 100644
--- a/clang/test/CodeGenCXX/stack-reuse-miscompile.cpp
+++ b/clang/test/CodeGenCXX/stack-reuse-miscompile.cpp
@@ -1,8 +1,4 @@
-// RUN: %clang_cc1 -triple armv7l-unknown-linux-gnueabihf -emit-llvm -O1 -disable-llvm-passes -std=c++03 %s -o - | FileCheck %s
-
-// This test should not to generate llvm.lifetime.start/llvm.lifetime.end for
-// f function because all temporary objects in this function are used for the
-// final result
+// RUN: %clang_cc1 -triple armv7l-unknown-linux-gnueabihf -emit-llvm -O1 -disable-llvm-passes -std=c++03 %s -o - | FileCheck %s --implicit-check-not=llvm.lifetime
 
 class S {
   char *ptr;
@@ -23,14 +19,36 @@ public:
 
 const char * f(S s)
 {
+// It's essential that the lifetimes of all three T temporaries here are
+// overlapping. They must all remain alive through the call to str().
+//
 // CHECK: [[T1:%.*]] = alloca %class.T, align 4
 // CHECK: [[T2:%.*]] = alloca %class.T, align 4
 // CHECK: [[T3:%.*]] = alloca %class.T, align 4
-// CHECK: [[T4:%.*]] = call %class.T* @_ZN1TC1EPKc(%class.T* [[T1]], i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str, i32 0, i32 0))
-// CHECK: [[T5:%.*]] = call %class.T* @_ZN1TC1E1S(%class.T* [[T2]], [2 x i32] %{{.*}})
-// CHECK: call void @_ZNK1T6concatERKS_(%class.T* sret [[T3]], %class.T* [[T1]], %class.T* dereferenceable(16) [[T2]])
-// CHECK: [[T6:%.*]] = call i8* @_ZNK1T3strEv(%class.T* [[T3]])
+//
+// FIXME: We could defer starting the lifetime of the return object of concat
+// until the call.
+// CHECK: [[T1i8:%.*]] = bitcast %class.T* [[T1]] to i8*
+// CHECK: call void @llvm.lifetime.start.p0i8(i64 16, i8* [[T1i8]])
+//
+// CHECK: [[T2i8:%.*]] = bitcast %class.T* [[T2]] to i8*
+// CHECK: call void @llvm.lifetime.start.p0i8(i64 16, i8* [[T2i8]])
+// CHECK: [[T4:%.*]] = call %class.T* @_ZN1TC1EPKc(%class.T* [[T2]], i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str, i32 0, i32 0))
+//
+// CHECK: [[T3i8:%.*]] = bitcast %class.T* [[T3]] to i8*
+// CHECK: call void @llvm.lifetime.start.p0i8(i64 16, i8* [[T3i8]])
+// CHECK: [[T5:%.*]] = call %class.T* @_ZN1TC1E1S(%class.T* [[T3]], [2 x i32] %{{.*}})
+//
+// CHECK: call void @_ZNK1T6concatERKS_(%class.T* sret [[T1]], %class.T* [[T2]], %class.T* dereferenceable(16) [[T3]])
+// CHECK: [[T6:%.*]] = call i8* @_ZNK1T3strEv(%class.T* [[T1]])
+//
+// CHECK: call void @llvm.lifetime.end.p0i8(
+// CHECK: call void @llvm.lifetime.end.p0i8(
+// CHECK: call void @llvm.lifetime.end.p0i8(
 // CHECK: ret i8* [[T6]]
 
   return T("[").concat(T(s)).str();
 }
+
+// CHECK: declare {{.*}}llvm.lifetime.start
+// CHECK: declare {{.*}}llvm.lifetime.end