diff --git a/cranelift/codegen/src/isa/x64/inst.isle b/cranelift/codegen/src/isa/x64/inst.isle
index 22973606b3f3..69ed608d130e 100644
--- a/cranelift/codegen/src/isa/x64/inst.isle
+++ b/cranelift/codegen/src/isa/x64/inst.isle
@@ -3184,7 +3184,7 @@
 ;; As a special case, reverse the arguments to the comparison when the LHS is a
 ;; constant. This ensures that we avoid moving the constant into a register when
 ;; performing the comparison.
-(rule 1 (emit_cmp cc (and (simm32_from_value a) (value_type ty)) b)
+(rule (emit_cmp cc (and (simm32_from_value a) (value_type ty)) b)
       (let ((size OperandSize (raw_operand_size_of_type ty)))
         (icmp_cond_result (x64_cmp size a b) (intcc_reverse cc))))