From f0fd1c0cd8d34b870a3011a36f5179d1b5f3547d Mon Sep 17 00:00:00 2001
From: Aaron Patterson <tenderlove@ruby-lang.org>
Date: Wed, 4 Sep 2019 16:00:19 -0700
Subject: [PATCH] Stash the imemo buf at the end of the ID list

Now we can reach the ID table buffer from the id table itself, so when
SCOPE nodes are marked we can keep the buffers alive.  This eliminates
the need for the "mark array" during normal parse / compile (IOW *not*
Ripper).
---
 node.c  | 10 +++++++++-
 parse.y | 24 ++++++++----------------
 2 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/node.c b/node.c
index 8a519f2947..064ce006ad 100644
--- a/node.c
+++ b/node.c
@@ -1218,6 +1218,15 @@ static void
 mark_ast_value(void *ctx, NODE * node)
 {
     switch (nd_type(node)) {
+        case NODE_SCOPE:
+        {
+            ID *buf = node->nd_tbl;
+            if (buf) {
+                unsigned int size = (unsigned int)*buf;
+                rb_gc_mark((VALUE)buf[size + 1]);
+            }
+            break;
+        }
         case NODE_LIT:
         case NODE_STR:
         case NODE_XSTR:
@@ -1226,7 +1235,6 @@ mark_ast_value(void *ctx, NODE * node)
         case NODE_DREGX:
         case NODE_DSYM:
         case NODE_ARGS:
-        case NODE_FOR:
         case NODE_ARYPTN:
             rb_gc_mark(node->nd_lit);
             break;
diff --git a/parse.y b/parse.y
index 08bedd2e51..b230ddb183 100644
--- a/parse.y
+++ b/parse.y
@@ -298,9 +298,6 @@ struct parser_params {
 #endif
 };
 
-#define new_tmpbuf() \
-    (rb_imemo_tmpbuf_t *)add_tmpbuf_mark_object(p, rb_imemo_tmpbuf_auto_free_pointer(NULL))
-
 #define intern_cstr(n,l,en) rb_intern3(n,l,en)
 
 #define STR_NEW(ptr,len) rb_enc_str_new((ptr),(len),p->enc)
@@ -337,13 +334,6 @@ rb_discard_node(struct parser_params *p, NODE *n)
 {
     rb_ast_delete_node(p->ast, n);
 }
-
-static inline VALUE
-add_tmpbuf_mark_object(struct parser_params *p, VALUE obj)
-{
-    rb_ast_add_mark_object(p->ast, obj);
-    return obj;
-}
 #endif
 
 static inline VALUE
@@ -2797,10 +2787,11 @@ primary		: literal
 			ID id = internal_id(p);
 			NODE *m = NEW_ARGS_AUX(0, 0, &NULL_LOC);
 			NODE *args, *scope, *internal_var = NEW_DVAR(id, &@2);
-			ID *tbl = ALLOC_N(ID, 2);
+			ID *tbl = ALLOC_N(ID, 3);
 			VALUE tmpbuf = rb_imemo_tmpbuf_auto_free_pointer(tbl);
                         RB_OBJ_WRITTEN(p->ast, Qnil, tmpbuf);
 			tbl[0] = 1 /* length of local var table */; tbl[1] = id /* internal id */;
+                        tbl[2] = tmpbuf;
 
 			switch (nd_type($2)) {
 			  case NODE_LASGN:
@@ -2821,7 +2812,6 @@ primary		: literal
 			args = new_args(p, m, 0, id, 0, new_args_tail(p, 0, 0, 0, &@2), &@2);
 			scope = NEW_NODE(NODE_SCOPE, tbl, $5, args, &@$);
 			$$ = NEW_FOR($4, scope, &@$);
-                        $$->nd_lit = tmpbuf;
 			fixpos($$, $2);
 		    /*% %*/
 		    /*% ripper: for!($2, $4, $5) %*/
@@ -11635,11 +11625,9 @@ local_tbl(struct parser_params *p)
     int cnt = cnt_args + cnt_vars;
     int i, j;
     ID *buf;
-    rb_imemo_tmpbuf_t *tmpbuf = new_tmpbuf();
 
     if (cnt <= 0) return 0;
-    buf = ALLOC_N(ID, cnt + 1);
-    tmpbuf->ptr = (void *)buf;
+    buf = ALLOC_N(ID, cnt + 2);
     MEMCPY(buf+1, p->lvtbl->args->tbl, ID, cnt_args);
     /* remove IDs duplicated to warn shadowing */
     for (i = 0, j = cnt_args+1; i < cnt_vars; ++i) {
@@ -11648,9 +11636,13 @@ local_tbl(struct parser_params *p)
 	    buf[j++] = id;
 	}
     }
-    if (--j < cnt) tmpbuf->ptr = (void *)REALLOC_N(buf, ID, (cnt = j) + 1);
+    if (--j < cnt) REALLOC_N(buf, ID, (cnt = j) + 2);
     buf[0] = cnt;
 
+    VALUE tmpbuf = rb_imemo_tmpbuf_auto_free_pointer(buf);
+    buf[cnt + 1] = (ID)tmpbuf;
+    RB_OBJ_WRITTEN(p->ast, Qnil, tmpbuf);
+
     return buf;
 }
 #endif