[SPIRV] Allow decoration attributes on fields. (#7453)

Fixes #7270

Author: s-perron

tools/clang/include/clang/Basic/Attr.td

@@ -1418,15 +1418,17 @@ def VKDecorateExt : InheritableAttr {
 
 def VKDecorateIdExt : InheritableAttr {
   let Spellings = [CXX11<"vk", "ext_decorate_id">];
-  let Subjects = SubjectList<[Function, Var, ParmVar, TypedefName], ErrorDiag>;
+  let Subjects =
+      SubjectList<[Function, Var, ParmVar, Field, TypedefName], ErrorDiag>;
   let Args = [UnsignedArgument<"decorate">, VariadicExprArgument<"arguments">];
   let LangOpts = [SPIRV];
   let Documentation = [Undocumented];
 }
 
 def VKDecorateStringExt : InheritableAttr {
   let Spellings = [CXX11<"vk", "ext_decorate_string">];
-  let Subjects = SubjectList<[Function, Var, ParmVar, TypedefName], ErrorDiag>;
+  let Subjects =
+      SubjectList<[Function, Var, ParmVar, Field, TypedefName], ErrorDiag>;
   let Args = [UnsignedArgument<"decorate">, VariadicStringArgument<"arguments">];
   let LangOpts = [SPIRV];
   let Documentation = [Undocumented];

tools/clang/test/CodeGenSPIRV/inline-spirv/spv.inline.decorate.member.hlsl

@@ -4,16 +4,22 @@ template<class T, class U>
 [[vk::ext_instruction(/*spv::OpBitcast*/124)]]
 T Bitcast(U);
 
-// CHECK: OpMemberDecorate %S 0 Offset 0
-// CHECK: OpMemberDecorate %S 1 Offset 16
-// CHECK: %S = OpTypeStruct %v4float %v4float
+// CHECK-DAG: OpMemberDecorate %S 0 Offset 0
+// CHECK-DAG: OpMemberDecorate %S 1 Offset 16
+// CHECK-DAG: %S = OpTypeStruct %v4float %v4float
 
 struct S
 {
     [[vk::ext_decorate(/*offset*/ 35, 0)]] float4 f1;
     [[vk::ext_decorate(/*offset*/ 35, 16)]] float4 f2;
 };
 
+// CHECK-DAG: OpDecorateString %out_var_SV_TARGET UserSemantic "raster_order_group_0"
+struct PixelOutput
+{
+	[[vk::location(0), vk::ext_decorate_string(5635, "raster_order_group_0")]] float4 rt0 : SV_TARGET;
+};
+
 using PointerType = vk::SpirvOpaqueType<
     /* OpTypePointer */ 32,
     /* PhysicalStorageBuffer */ vk::Literal<vk::integral_constant<uint,5349> >,
@@ -27,14 +33,16 @@ S Load(PointerType pointer,
 
 uint64_t address;
 
-float4 main() : SV_TARGET
+PixelOutput main()
 {
 
 // CHECK: [[BC:%[0-9]+]] = OpBitcast %_ptr_PhysicalStorageBuffer_S {{%[0-9]+}}
   PointerType ptr = Bitcast<PointerType>(address);
 
+PixelOutput output;
 // CHECK: [[LD:%[0-9]+]] = OpLoad %S [[BC]] Aligned 32
 // CHECK: [[RET:%[0-9]+]] = OpCompositeExtract %v4float [[LD]] 0
 // CHECK: OpStore %out_var_SV_TARGET [[RET]]
-  return Load(ptr).f1;
+output.rt0 = Load(ptr).f1;
+  return output;
 }