Use rb_fstring for "defined" strings.

We can take advantage of fstrings to de-duplicate the defined strings.
This means we don't need to keep the list of defined strings on the VM
(or register them as mark objects)

1 files changed, 2 insertions, 2 deletions

diff --git a/insns.def b/insns.def
index 1dc0bb3365..5704bf44e7 100644
--- a/insns.def
+++ b/insns.def
@@ -662,14 +662,14 @@ adjuststack
 /* defined? */
 DEFINE_INSN
 defined
-(rb_num_t op_type, VALUE obj, VALUE needstr)
+(rb_num_t op_type, VALUE obj, VALUE pushval)
 (VALUE v)
 (VALUE val)
 // attr bool leaf = leafness_of_defined(op_type);
 {
     val = Qnil;
     if (vm_defined(ec, GET_CFP(), op_type, obj, v)) {
-      val = needstr;
+      val = pushval;
     }
 }