more perf

Author: BoxyUwU

compiler/rustc_type_ir/src/binder.rs

@@ -733,10 +733,13 @@ impl<'a, I: Interner> TypeFolder<I> for ArgFolder<'a, I> {
     }
 
     fn fold_const(&mut self, c: I::Const) -> I::Const {
-        if let ty::ConstKind::Param(p) = c.kind() {
-            self.const_for_param(p, c)
-        } else {
-            c.super_fold_with(self)
+        if !c.has_param() {
+            return c
+        }
+        
+        match c.kind() {
+            ty::ConstKind::Param(p) => self.const_for_param(p, c),
+            _ => c.super_fold_with(self)
         }
     }