Index: clang/include/clang/Basic/BuiltinsAMDGPU.def
===================================================================
--- clang/include/clang/Basic/BuiltinsAMDGPU.def
+++ clang/include/clang/Basic/BuiltinsAMDGPU.def
@@ -33,9 +33,9 @@
 BUILTIN(__builtin_amdgcn_workitem_id_y, "Ui", "nc")
 BUILTIN(__builtin_amdgcn_workitem_id_z, "Ui", "nc")
 
-BUILTIN(__builtin_amdgcn_workgroup_size_x, "Ui", "nc")
-BUILTIN(__builtin_amdgcn_workgroup_size_y, "Ui", "nc")
-BUILTIN(__builtin_amdgcn_workgroup_size_z, "Ui", "nc")
+BUILTIN(__builtin_amdgcn_workgroup_size_x, "Us", "nc")
+BUILTIN(__builtin_amdgcn_workgroup_size_y, "Us", "nc")
+BUILTIN(__builtin_amdgcn_workgroup_size_z, "Us", "nc")
 
 BUILTIN(__builtin_amdgcn_mbcnt_hi, "UiUiUi", "nc")
 BUILTIN(__builtin_amdgcn_mbcnt_lo, "UiUiUi", "nc")
Index: clang/test/CodeGenOpenCL/builtins-amdgcn.cl
===================================================================
--- clang/test/CodeGenOpenCL/builtins-amdgcn.cl
+++ clang/test/CodeGenOpenCL/builtins-amdgcn.cl
@@ -538,7 +538,7 @@
 void test_get_workgroup_size(int d, global int *out)
 {
 	switch (d) {
-	case 0: *out = __builtin_amdgcn_workgroup_size_x(); break;
+	case 0: *out = __builtin_amdgcn_workgroup_size_x() + 1; break;
 	case 1: *out = __builtin_amdgcn_workgroup_size_y(); break;
 	case 2: *out = __builtin_amdgcn_workgroup_size_z(); break;
 	default: *out = 0;