diff --git a/mlir/include/mlir/IR/OpImplementation.h b/mlir/include/mlir/IR/OpImplementation.h
--- a/mlir/include/mlir/IR/OpImplementation.h
+++ b/mlir/include/mlir/IR/OpImplementation.h
@@ -452,6 +452,9 @@
   /// Parse a single operand.
   virtual ParseResult parseOperand(OperandType &result) = 0;
 
+  /// Parse a single operand if present.
+  virtual OptionalParseResult parseOptionalOperand(OperandType &result) = 0;
+
   /// These are the supported delimiters around operand lists and region
   /// argument lists, used by parseOperandList and parseRegionArgumentList.
   enum class Delimiter {
diff --git a/mlir/lib/Parser/Parser.cpp b/mlir/lib/Parser/Parser.cpp
--- a/mlir/lib/Parser/Parser.cpp
+++ b/mlir/lib/Parser/Parser.cpp
@@ -4253,6 +4253,13 @@
     return success();
   }
 
+  /// Parse a single operand if present.
+  OptionalParseResult parseOptionalOperand(OperandType &result) override {
+    if (parser.getToken().is(Token::percent_identifier))
+      return parseOperand(result);
+    return llvm::None;
+  }
+
   /// Parse zero or more SSA comma-separated operand references with a specified
   /// surrounding delimiter, and an optional required operand count.
   ParseResult parseOperandList(SmallVectorImpl<OperandType> &result,