add sema tests

Author: Keenuts

clang/lib/Sema/SemaHLSL.cpp

@@ -1159,7 +1159,7 @@ bool SemaHLSL::diagnosePositionType(QualType T, const ParsedAttr &AL) {
 
   if (!T->hasFloatingRepresentation() || (VT && VT->getNumElements() > 4)) {
     Diag(AL.getLoc(), diag::err_hlsl_attr_invalid_type)
-        << AL << "float/float1/float2/float3";
+        << AL << "float/float1/float2/float3/float4";
     return false;
   }
 

clang/test/SemaHLSL/Semantics/position.ps.size.hlsl

@@ -0,0 +1,10 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-library -x hlsl -finclude-default-header -o - %s -verify -verify-ignore-unexpected
+// RUN: %clang_cc1 -triple spirv-unknown-vulkan1.3-library  -x hlsl -finclude-default-header -o - %s -verify -verify-ignore-unexpected
+
+// expected-error@+1 {{attribute 'SV_Position' only applies to a field or parameter of type 'float/float1/float2/float3/float4'}}
+void main(vector<float, 5> a : SV_Position) {
+}
+
+// expected-error@+1 {{attribute 'SV_Position' only applies to a field or parameter of type 'float/float1/float2/float3/float4'}}
+void main(int2 a : SV_Position) {
+}