enable constant cache on ractors

constant cache `IC` is accessed by non-atomic manner and there are
thread-safety issues, so Ruby 3.0 disables to use const cache on
non-main ractors.

This patch enables it by introducing `imemo_constcache` and allocates
it by every re-fill of const cache like `imemo_callcache`.
[Bug #17510]

Now `IC` only has one entry `IC::entry` and it points to
`iseq_inline_constant_cache_entry`, managed by T_IMEMO object.

`IC` is atomic data structure so `rb_mjit_before_vm_ic_update()` and
`rb_mjit_after_vm_ic_update()` is not needed.

1 files changed, 5 insertions, 4 deletions

diff --git a/insns.def b/insns.def
index 5bfcf997ce..51e130786b 100644
--- a/insns.def
+++ b/insns.def
@@ -1023,9 +1023,10 @@ opt_getinlinecache
 ()
 (VALUE val)
 {
-    if (vm_ic_hit_p(ic->ic_serial, ic->ic_cref, GET_EP())) {
-	val = ic->value;
-	JUMP(dst);
+    struct iseq_inline_constant_cache_entry *ice = ic->entry;
+    if (ice && vm_ic_hit_p(ice, GET_EP())) {
+        val = ice->value;
+        JUMP(dst);
     }
     else {
 	val = Qnil;
@@ -1039,7 +1040,7 @@ opt_setinlinecache
 (VALUE val)
 (VALUE val)
 {
-    vm_ic_update(ic, val, GET_EP());
+    vm_ic_update(GET_ISEQ(), ic, val, GET_EP());
 }
 
 /* run iseq only once */