diff --git a/src/hotspot/cpu/riscv/riscv.ad b/src/hotspot/cpu/riscv/riscv.ad
index 716ffae27b598..9adcc1d9c5a9f 100644
--- a/src/hotspot/cpu/riscv/riscv.ad
+++ b/src/hotspot/cpu/riscv/riscv.ad
@@ -8426,6 +8426,17 @@ instruct castVV(vReg dst)
   ins_pipe(pipe_class_empty);
 %}
 
+instruct castVVMask(vRegMask dst)
+%{
+  match(Set dst (CastVV dst));
+
+  size(0);
+  format %{ "# castVV of $dst" %}
+  ins_encode(/* empty encoding */);
+  ins_cost(0);
+  ins_pipe(pipe_class_empty);
+%}
+
 // ============================================================================
 // Convert Instructions