Mark C++ reference parameters as dereferenceable

Because references must be initialized using some evaluated expression, they
must point to something, and a callee can assume the reference parameter is
dereferenceable. Taking advantage of a new attribute just added to LLVM, mark
them as such.

Because dereferenceability in addrspace(0) implies nonnull in the backend, we
don't need both attributes. However, we need to know the size of the object to
use the dereferenceable attribute, so for incomplete types we still emit only
nonnull.

llvm-svn: 213386

1 files changed, 2 insertions, 2 deletions

diff --git a/clang/test/CodeGenCXX/default-arg-temps.cpp b/clang/test/CodeGenCXX/default-arg-temps.cpp
index 7910942eee9..6a7f43a5128 100644
--- a/clang/test/CodeGenCXX/default-arg-temps.cpp
+++ b/clang/test/CodeGenCXX/default-arg-temps.cpp
@@ -16,12 +16,12 @@ public:
 // CHECK-LABEL: define void @_Z1gv()
 void g() {
   // CHECK:      call void @_ZN1TC1Ev([[T:%.*]]* [[AGG1:%.*]])
-  // CHECK-NEXT: call void @_Z1fRK1T([[T]]* nonnull [[AGG1]])
+  // CHECK-NEXT: call void @_Z1fRK1T([[T]]* dereferenceable({{[0-9]+}}) [[AGG1]])
   // CHECK-NEXT: call void @_ZN1TD1Ev([[T]]* [[AGG1]])
   f();
 
   // CHECK-NEXT: call void @_ZN1TC1Ev([[T:%.*]]* [[AGG2:%.*]])
-  // CHECK-NEXT: call void @_Z1fRK1T([[T]]* nonnull [[AGG2]])
+  // CHECK-NEXT: call void @_Z1fRK1T([[T]]* dereferenceable({{[0-9]+}}) [[AGG2]])
   // CHECK-NEXT: call void @_ZN1TD1Ev([[T]]* [[AGG2]])
   f();