diff --git a/clang/include/clang/Basic/BuiltinsWebAssembly.def b/clang/include/clang/Basic/BuiltinsWebAssembly.def
--- a/clang/include/clang/Basic/BuiltinsWebAssembly.def
+++ b/clang/include/clang/Basic/BuiltinsWebAssembly.def
@@ -185,9 +185,9 @@
 TARGET_BUILTIN(__builtin_wasm_trunc_saturate_u_i32x4_f32x4, "V4iV4f", "nc", "simd128")
 
 TARGET_BUILTIN(__builtin_wasm_narrow_s_i8x16_i16x8, "V16ScV8sV8s", "nc", "simd128")
-TARGET_BUILTIN(__builtin_wasm_narrow_u_i8x16_i16x8, "V16UcV8UsV8Us", "nc", "simd128")
+TARGET_BUILTIN(__builtin_wasm_narrow_u_i8x16_i16x8, "V16UcV8sV8s", "nc", "simd128")
 TARGET_BUILTIN(__builtin_wasm_narrow_s_i16x8_i32x4, "V8sV4iV4i", "nc", "simd128")
-TARGET_BUILTIN(__builtin_wasm_narrow_u_i16x8_i32x4, "V8UsV4UiV4Ui", "nc", "simd128")
+TARGET_BUILTIN(__builtin_wasm_narrow_u_i16x8_i32x4, "V8UsV4iV4i", "nc", "simd128")
 
 TARGET_BUILTIN(__builtin_wasm_trunc_sat_zero_s_f64x2_i32x4, "V4iV2d", "nc", "simd128")
 TARGET_BUILTIN(__builtin_wasm_trunc_sat_zero_u_f64x2_i32x4, "V4UiV2d", "nc", "simd128")
diff --git a/clang/test/CodeGen/builtins-wasm.c b/clang/test/CodeGen/builtins-wasm.c
--- a/clang/test/CodeGen/builtins-wasm.c
+++ b/clang/test/CodeGen/builtins-wasm.c
@@ -857,7 +857,7 @@
   // WEBASSEMBLY: ret
 }
 
-u8x16 narrow_u_i8x16_i16x8(u16x8 low, u16x8 high) {
+u8x16 narrow_u_i8x16_i16x8(i16x8 low, i16x8 high) {
   return __builtin_wasm_narrow_u_i8x16_i16x8(low, high);
   // WEBASSEMBLY: call <16 x i8> @llvm.wasm.narrow.unsigned.v16i8.v8i16(
   // WEBASSEMBLY-SAME: <8 x i16> %low, <8 x i16> %high)
@@ -871,7 +871,7 @@
   // WEBASSEMBLY: ret
 }
 
-u16x8 narrow_u_i16x8_i32x4(u32x4 low, u32x4 high) {
+u16x8 narrow_u_i16x8_i32x4(i32x4 low, i32x4 high) {
   return __builtin_wasm_narrow_u_i16x8_i32x4(low, high);
   // WEBASSEMBLY: call <8 x i16> @llvm.wasm.narrow.unsigned.v8i16.v4i32(
   // WEBASSEMBLY-SAME: <4 x i32> %low, <4 x i32> %high)