[clang] Add concepts for raw buffers (PR #119643)

[Helena Kotas via cfe-commits]

================
@@ -868,8 +868,54 @@ static Expr *constructTypedBufferConstraintExpr(Sema &S, SourceLocation NameLoc,
   return TypedResExpr;
 }
 
-static ConceptDecl *constructTypedBufferConceptDecl(Sema &S,
-                                                    NamespaceDecl *NSD) {
+static Expr *constructStructuredBufferConstraintExpr(Sema &S,
+                                                     SourceLocation NameLoc,
+                                                     TemplateTypeParmDecl *T) {
+  ASTContext &Context = S.getASTContext();
+
+  // Obtain the QualType for 'bool'
+  QualType BoolTy = Context.BoolTy;
+
+  // Create a QualType that points to this TemplateTypeParmDecl
+  QualType TType = Context.getTypeDeclType(T);
+
+  // Create a TypeSourceInfo for the template type parameter 'T'
+  TypeSourceInfo *TTypeSourceInfo =
+      Context.getTrivialTypeSourceInfo(TType, NameLoc);
+
+  TypeTraitExpr *IsIntangibleExpr =
+      TypeTraitExpr::Create(Context, BoolTy, NameLoc, UTT_IsIntangibleType,
+                            {TTypeSourceInfo}, NameLoc, true);
+
+  // negate IsIntangibleExpr
+  UnaryOperator *NotIntangibleExpr = UnaryOperator::Create(
+      Context, IsIntangibleExpr, UO_Not, BoolTy, VK_LValue, OK_Ordinary,
+      NameLoc, false, FPOptionsOverride());
+
+  // element types also may not be of 0 size
+  UnaryExprOrTypeTraitExpr *SizeOfExpr = new (Context) UnaryExprOrTypeTraitExpr(
+      UETT_SizeOf, TTypeSourceInfo, BoolTy, NameLoc, NameLoc);
+
+  // Create a BinaryOperator that checks if the size of the type is not equal to
+  // 1 Empty structs have a size of 1 in HLSL, so we need to check for that
+  IntegerLiteral *rhs = IntegerLiteral::Create(
+      Context, llvm::APInt(Context.getTypeSize(Context.getSizeType()), 1, true),
+      Context.getSizeType(), NameLoc);
+
+  BinaryOperator *SizeGEQOneExpr =
+      BinaryOperator::Create(Context, SizeOfExpr, rhs, BO_GE, BoolTy, VK_LValue,
+                             OK_Ordinary, NameLoc, FPOptionsOverride());
+
+  // Combine the two constraints
+  BinaryOperator *CombinedExpr = BinaryOperator::Create(
+      Context, NotIntangibleExpr, SizeGEQOneExpr, BO_LAnd, BoolTy, VK_LValue,
+      OK_Ordinary, NameLoc, FPOptionsOverride());
+
+  return CombinedExpr;
+}
+
+static ConceptDecl *constructTypedBufferConceptDecl(Sema &S, NamespaceDecl *NSD,
+                                                    bool isTypedBuffer) {
----------------
hekota wrote:

This function should not have "Typed" in the name since it can create both typed and structured buffer concept decls.

https://github.com/llvm/llvm-project/pull/119643