Index: lib/Headers/prfchwintrin.h
===================================================================
--- lib/Headers/prfchwintrin.h
+++ lib/Headers/prfchwintrin.h
@@ -30,6 +30,12 @@
 
 #if defined(__PRFCHW__) || defined(__3dNOW__)
 static __inline__ void __attribute__((__always_inline__, __nodebug__))
+_m_prefetch(void *__P)
+{
+  __builtin_prefetch (__P, 0, 3 /* _MM_HINT_T0 */);
+}
+
+static __inline__ void __attribute__((__always_inline__, __nodebug__))
 _m_prefetchw(void *__P)
 {
   __builtin_prefetch (__P, 1, 3 /* _MM_HINT_T0 */);
Index: test/CodeGen/prefetchw-builtins.c
===================================================================
--- test/CodeGen/prefetchw-builtins.c
+++ test/CodeGen/prefetchw-builtins.c
@@ -5,8 +5,14 @@
 
 #include <x86intrin.h>
 
-void prefetch_w(void *p) {
+void test_m_prefetch_w(void *p) {
   return _m_prefetchw(p);
-// CHECK: @prefetch_w
+// CHECK-LABEL: define void @test_m_prefetch_w
 // CHECK: call void @llvm.prefetch({{.*}}, i32 1, i32 3, i32 1)
 }
+
+void test_m_prefetch(void *p) {
+  return _m_prefetch(p);
+  // CHECK-LABEL: define void @test_m_prefetch
+  // CHECK: call void @llvm.prefetch({{.*}}, i32 0, i32 3, i32 1)
+}