Revert "Finer-grained inline constant cache invalidation"

This reverts commits for [Feature #18589]:
* 8008fb7352abc6fba433b99bf20763cf0d4adb38
  "Update formatting per feedback"
* 8f6eaca2e19828e92ecdb28b0fe693d606a03f96
  "Delete ID from constant cache table if it becomes empty on ISEQ free"
* 629908586b4bead1103267652f8b96b1083573a8
  "Finer-grained inline constant cache invalidation"

MSWin builds on AppVeyor have been crashing since the merger.

1 files changed, 32 insertions, 8 deletions

diff --git a/vm_core.h b/vm_core.h
index 76caafbdbb..d985bd40ba 100644
--- a/vm_core.h
+++ b/vm_core.h
@@ -229,14 +229,44 @@ struct iseq_inline_constant_cache_entry {
     VALUE flags;
 
     VALUE value;              // v0
-    VALUE _unused1;           // v1
-    VALUE _unused2;           // v2
+    union ic_serial_entry ic_serial; // v1, v2
     const rb_cref_t *ic_cref; // v3
 };
 STATIC_ASSERT(sizeof_iseq_inline_constant_cache_entry,
               (offsetof(struct iseq_inline_constant_cache_entry, ic_cref) +
 	       sizeof(const rb_cref_t *)) <= sizeof(struct RObject));
 
+#if SIZEOF_SERIAL_T <= SIZEOF_VALUE
+
+#define GET_IC_SERIAL(ice) (ice)->ic_serial.raw
+#define SET_IC_SERIAL(ice, v) (ice)->ic_serial.raw = (v)
+
+#else
+
+static inline rb_serial_t
+get_ic_serial(const struct iseq_inline_constant_cache_entry *ice)
+{
+    union ic_serial_entry tmp;
+    tmp.data[0] = ice->ic_serial.data[0];
+    tmp.data[1] = ice->ic_serial.data[1];
+    return tmp.raw;
+}
+
+#define GET_IC_SERIAL(ice) get_ic_serial(ice)
+
+static inline void
+set_ic_serial(struct iseq_inline_constant_cache_entry *ice, rb_serial_t v)
+{
+    union ic_serial_entry tmp;
+    tmp.raw = v;
+    ice->ic_serial.data[0] = tmp.data[0];
+    ice->ic_serial.data[1] = tmp.data[1];
+}
+
+#define SET_IC_SERIAL(ice, v) set_ic_serial((ice), (v))
+
+#endif
+
 struct iseq_inline_constant_cache {
     struct iseq_inline_constant_cache_entry *entry;
     // For YJIT: the index to the opt_getinlinecache instruction in the same iseq.
@@ -692,12 +722,6 @@ typedef struct rb_vm_struct {
     struct rb_id_table *negative_cme_table;
     st_table *overloaded_cme_table; // cme -> overloaded_cme
 
-    // This id table contains a mapping from ID to ICs. It does this with ID
-    // keys and nested st_tables as values. The nested tables have ICs as keys
-    // and Qtrue as values. It is used when inline constant caches need to be
-    // invalidated or ISEQs are being freed.
-    struct rb_id_table *constant_cache;
-
 #ifndef VM_GLOBAL_CC_CACHE_TABLE_SIZE
 #define VM_GLOBAL_CC_CACHE_TABLE_SIZE 1023
 #endif