add verifier

Author: ftynse

mlir/include/mlir/Dialect/LLVMIR/LLVMAttrDefs.td

@@ -900,6 +900,8 @@ def LLVM_AliasScopeAttr : LLVM_Attr<"AliasScope", "alias_scope"> {
   let summary = "LLVM dialect alias scope";
 
   let assemblyFormat = "`<` struct(params) `>`";
+
+  let genVerifyDecl = 1;
 }
 
 def LLVM_AliasScopeArrayAttr

mlir/lib/Dialect/LLVMIR/IR/LLVMAttrs.cpp

@@ -52,6 +52,23 @@ void LLVMDialect::registerAttributes() {
       >();
 }
 
+//===----------------------------------------------------------------------===//
+// AliasScopeAttr
+//===----------------------------------------------------------------------===//
+
+LogicalResult
+AliasScopeAttr::verify(function_ref<InFlightDiagnostic()> emitError,
+                       Attribute id, AliasScopeDomainAttr domain,
+                       StringAttr description) {
+  (void)domain;
+  (void)description;
+  if (!llvm::isa<StringAttr, DistinctAttr>(id))
+    return emitError()
+           << "id of an alias scope must be a StringAttr or a DistrinctAttr";
+
+  return success();
+}
+
 //===----------------------------------------------------------------------===//
 // DINodeAttr
 //===----------------------------------------------------------------------===//