[PR40778] Add addr space conversion when binding reference to a temporary.

Anastasia Stulova · Anastasia Stulova · commit d3ae87ee0d6c · 2019-03-06T13:02:41.000Z
This change fixes temporary materialization to happen in the right (default) address space when binding to it a reference of different type. It adds address space conversion afterwards to match the addr space of a reference. Differential Revision: https://reviews.llvm.org/D58634 llvm-svn: 355499
diff --git a/clang/include/clang/AST/Type.h b/clang/include/clang/AST/Type.h
@@ -317,6 +317,11 @@ class Qualifiers {
     qs.removeObjCLifetime();
     return qs;
   }
+  Qualifiers withoutAddressSpace() const {
+    Qualifiers qs = *this;
+    qs.removeAddressSpace();
+    return qs;
+  }
 
   bool hasObjCLifetime() const { return Mask & LifetimeMask; }
   ObjCLifetime getObjCLifetime() const {
diff --git a/clang/lib/Sema/SemaInit.cpp b/clang/lib/Sema/SemaInit.cpp
@@ -4760,7 +4760,15 @@ static void TryReferenceInitializationCore(Sema &S,
   //        copy-initialization (8.5). The reference is then bound to the
   //        temporary. [...]
 
-  InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1);
+  // Ignore address space of reference type at this point and perform address
+  // space conversion after the reference binding step.
+  QualType cv1T1IgnoreAS =
+      T1Quals.hasAddressSpace()
+          ? S.Context.getQualifiedType(T1, T1Quals.withoutAddressSpace())
+          : cv1T1;
+
+  InitializedEntity TempEntity =
+      InitializedEntity::InitializeTemporary(cv1T1IgnoreAS);
 
   // FIXME: Why do we use an implicit conversion here rather than trying
   // copy-initialization?
@@ -4795,8 +4803,9 @@ static void TryReferenceInitializationCore(Sema &S,
   //        than, cv2; otherwise, the program is ill-formed.
   unsigned T1CVRQuals = T1Quals.getCVRQualifiers();
   unsigned T2CVRQuals = T2Quals.getCVRQualifiers();
-  if (RefRelationship == Sema::Ref_Related &&
-      (T1CVRQuals | T2CVRQuals) != T1CVRQuals) {
+  if ((RefRelationship == Sema::Ref_Related &&
+       (T1CVRQuals | T2CVRQuals) != T1CVRQuals) ||
+      !T1Quals.isAddressSpaceSupersetOf(T2Quals)) {
     Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers);
     return;
   }
@@ -4810,7 +4819,11 @@ static void TryReferenceInitializationCore(Sema &S,
     return;
   }
 
-  Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true);
+  Sequence.AddReferenceBindingStep(cv1T1IgnoreAS, /*bindingTemporary=*/true);
+
+  if (T1Quals.hasAddressSpace())
+    Sequence.AddQualificationConversionStep(cv1T1, isLValueRef ? VK_LValue
+                                                               : VK_XValue);
 }
 
 /// Attempt character array initialization from a string literal
diff --git a/clang/test/CodeGenOpenCLCXX/addrspace-references.cl b/clang/test/CodeGenOpenCLCXX/addrspace-references.cl
@@ -0,0 +1,14 @@
+//RUN: %clang_cc1 %s -cl-std=c++ -triple spir -emit-llvm -o - | FileCheck %s
+
+int bar(const unsigned int &i);
+// CHECK-LABEL: define spir_func void @_Z3foov() 
+void foo() {
+  // The generic addr space reference parameter object will be bound
+  // to a temporary value allocated in private addr space. We need an
+  // addrspacecast before passing the value to the function.
+  // CHECK: [[REF:%.*]] = alloca i32
+  // CHECK: store i32 1, i32* [[REF]]
+  // CHECK: [[REG:%[0-9]+]] = addrspacecast i32* [[REF]] to i32 addrspace(4)*
+  // CHECK: call spir_func i32 @_Z3barRU3AS4Kj(i32 addrspace(4)* nonnull dereferenceable(4) [[REG]])
+  bar(1);
+}
