[HLSL] Split out the ROV attribute from the resource attribute, make it a new spellable attribute. (#102414)

Much like #98193, this PR takes some more data out of the resource
attribute, specifically the ROV data.
This PR introduces a new attribute called HLSLROVAttr, which contains
data on whether or not the decl the attribute applies to is an ROV.
Tests were added to ensure the attribute is found on the AST.
This attribute may take any boolean condition as an argument. If the
condition is true, then the object the attribute applies to "is" an ROV.
Fixes ##102392

Author: bob80905

clang/include/clang/Basic/Attr.td

@@ -4599,12 +4599,18 @@ def HLSLResource : InheritableAttr {
           "CBuffer", "Sampler", "TBuffer", "RTAccelerationStructure",
           "FeedbackTexture2D", "FeedbackTexture2DArray"
         ],
-        /*opt=*/0, /*fake=*/0, /*isExternalType=*/1, /*isCovered=*/0>,
-    DefaultBoolArgument<"isROV", /*default=*/0>
+        /*opt=*/0, /*fake=*/0, /*isExternalType=*/1, /*isCovered=*/0>
   ];
   let Documentation = [InternalOnly];
 }
 
+def HLSLROV : InheritableAttr {
+  let Spellings = [CXX11<"hlsl", "is_rov">];
+  let Subjects = SubjectList<[Struct]>;
+  let LangOpts = [HLSL]; 
+  let Documentation = [InternalOnly];
+}
+
 def HLSLResourceClass : InheritableAttr {
   let Spellings = [CXX11<"hlsl", "resource_class">];
   let Subjects = SubjectList<[Struct]>;

clang/include/clang/Sema/SemaHLSL.h

@@ -56,6 +56,7 @@ class SemaHLSL : public SemaBase {
   void handleSV_DispatchThreadIDAttr(Decl *D, const ParsedAttr &AL);
   void handlePackOffsetAttr(Decl *D, const ParsedAttr &AL);
   void handleShaderAttr(Decl *D, const ParsedAttr &AL);
+  void handleROVAttr(Decl *D, const ParsedAttr &AL);
   void handleResourceClassAttr(Decl *D, const ParsedAttr &AL);
   void handleResourceBindingAttr(Decl *D, const ParsedAttr &AL);
   void handleParamModifierAttr(Decl *D, const ParsedAttr &AL);

clang/lib/CodeGen/CGHLSLRuntime.cpp

@@ -301,7 +301,7 @@ void CGHLSLRuntime::annotateHLSLResource(const VarDecl *D, GlobalVariable *GV) {
 
     llvm::hlsl::ResourceClass RC = HLSLResClassAttr->getResourceClass();
     llvm::hlsl::ResourceKind RK = HLSLResAttr->getResourceKind();
-    bool IsROV = HLSLResAttr->getIsROV();
+    bool IsROV = FD->hasAttr<HLSLROVAttr>();
     llvm::hlsl::ElementType ET = calculateElementType(CGM.getContext(), Ty);
 
     BufferResBinding Binding(D->getAttr<HLSLResourceBindingAttr>());

clang/lib/Sema/HLSLExternalSemaSource.cpp

@@ -96,8 +96,11 @@ struct BuiltinTypeDeclBuilder {
         nullptr, false, InClassInitStyle::ICIS_NoInit);
     Field->setAccess(Access);
     Field->setImplicit(true);
-    for (Attr *A : Attrs)
-      Field->addAttr(A);
+    for (Attr *A : Attrs) {
+      if (A)
+        Field->addAttr(A);
+    }
+
     Record->addDecl(Field);
     Fields[Name] = Field;
     return *this;
@@ -116,12 +119,15 @@ struct BuiltinTypeDeclBuilder {
             QualType(TTD->getTypeForDecl(), 0));
     }
     // add handle member
-    llvm::SmallVector<Attr *, 2> Attrs;
     Attr *ResourceClassAttr =
         HLSLResourceClassAttr::CreateImplicit(Record->getASTContext(), RC);
     Attr *ResourceAttr =
-        HLSLResourceAttr::CreateImplicit(Record->getASTContext(), RK, IsROV);
-    addMemberVariable("h", Ty, {ResourceClassAttr, ResourceAttr}, Access);
+        HLSLResourceAttr::CreateImplicit(Record->getASTContext(), RK);
+    Attr *ROVAttr =
+        IsROV ? HLSLROVAttr::CreateImplicit(Record->getASTContext()) : nullptr;
+    addMemberVariable("h", Ty, {ResourceClassAttr, ResourceAttr, ROVAttr},
+                      Access);
+
     return *this;
   }
 

clang/lib/Sema/SemaDeclAttr.cpp

@@ -6901,6 +6901,9 @@ ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D, const ParsedAttr &AL,
   case ParsedAttr::AT_HLSLResourceBinding:
     S.HLSL().handleResourceBindingAttr(D, AL);
     break;
+  case ParsedAttr::AT_HLSLROV:
+    handleSimpleAttribute<HLSLROVAttr>(S, D, AL);
+    break;
   case ParsedAttr::AT_HLSLResourceClass:
     S.HLSL().handleResourceClassAttr(D, AL);
     break;

clang/test/Misc/pragma-attribute-supported-attributes-list.test

@@ -81,6 +81,7 @@
 // CHECK-NEXT: FunctionReturnThunks (SubjectMatchRule_function)
 // CHECK-NEXT: GNUInline (SubjectMatchRule_function)
 // CHECK-NEXT: HIPManaged (SubjectMatchRule_variable)
+// CHECK-NEXT: HLSLROV (SubjectMatchRule_record_not_is_union)
 // CHECK-NEXT: HLSLResourceClass (SubjectMatchRule_record_not_is_union)
 // CHECK-NEXT: Hot (SubjectMatchRule_function)
 // CHECK-NEXT: HybridPatchable (SubjectMatchRule_function)

clang/test/ParserHLSL/hlsl_is_rov_attr.hlsl

@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-compute -x hlsl -ast-dump -o - %s | FileCheck %s
+
+
+// CHECK: -HLSLROVAttr 0x{{[0-9a-f]+}} <col:10, col:16>
+struct [[hlsl::is_rov]] Eg1 {
+  int i;  
+};
+
+Eg1 e1;

clang/test/ParserHLSL/hlsl_is_rov_attr_error.hlsl

@@ -0,0 +1,15 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-compute -x hlsl -ast-dump -o - %s -verify
+
+// expected-error@+1{{'is_rov' attribute takes no arguments}}
+struct [[hlsl::is_rov(3)]] Eg1 {
+  int i;  
+};
+
+Eg1 e1;
+
+// expected-error@+1{{use of undeclared identifier 'gibberish'}}
+struct [[hlsl::is_rov(gibberish)]] Eg2 {
+  int i;  
+};
+
+Eg2 e2;

clang/test/ParserHLSL/hlsl_resource_handle_attrs.hlsl

@@ -1,14 +1,15 @@
 // RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -x hlsl -ast-dump -o - %s | FileCheck %s
 
-// CHECK: -ClassTemplateDecl 0x{{[0-9a-f]+}} <<invalid sloc>> <invalid sloc> implicit RWBuffer
-// CHECK: -CXXRecordDecl 0x{{[0-9a-f]+}} <<invalid sloc>> <invalid sloc> implicit class RWBuffer definition
-// CHECK: -FieldDecl 0x{{[0-9a-f]+}} <<invalid sloc>> <invalid sloc> implicit h 'element_type *'
-// CHECK: -HLSLResourceClassAttr 0x{{[0-9a-f]+}} <<invalid sloc>> Implicit UAV
-// CHECK: -HLSLResourceAttr 0x{{[0-9a-f]+}} <<invalid sloc>> Implicit TypedBuffer
-RasterizerOrderedBuffer<vector<float, 4> > BufferArray3[4] : register(u4, space1);
-
 // CHECK: -ClassTemplateSpecializationDecl 0x{{[0-9a-f]+}} <<invalid sloc>> <invalid sloc> class RWBuffer definition implicit_instantiation
 // CHECK: -FieldDecl 0x{{[0-9a-f]+}} <<invalid sloc>> <invalid sloc> implicit referenced h 'float *'
 // CHECK: -HLSLResourceClassAttr 0x{{[0-9a-f]+}} <<invalid sloc>> Implicit UAV
 // CHECK: -HLSLResourceAttr 0x{{[0-9a-f]+}} <<invalid sloc>> Implicit TypedBuffer
 RWBuffer<float> Buffer1;
+
+// CHECK: -ClassTemplateDecl 0x{{[0-9a-f]+}} <<invalid sloc>> <invalid sloc> implicit RasterizerOrderedBuffer
+// CHECK: -CXXRecordDecl 0x{{[0-9a-f]+}} <<invalid sloc>> <invalid sloc> implicit class RasterizerOrderedBuffer definition
+// CHECK: -FieldDecl 0x{{[0-9a-f]+}} <<invalid sloc>> <invalid sloc> implicit h 'element_type *'
+// CHECK: -HLSLResourceClassAttr 0x{{[0-9a-f]+}} <<invalid sloc>> Implicit UAV
+// CHECK: -HLSLResourceAttr 0x{{[0-9a-f]+}} <<invalid sloc>> Implicit TypedBuffer
+// CHECK: -HLSLROVAttr 0x{{[0-9a-f]+}} <<invalid sloc>> Implicit
+RasterizerOrderedBuffer<vector<float, 4> > BufferArray3[4] : register(u4, space1);