From 520df805a97989018d17e02c78ed8cb1c6f27fa1 Mon Sep 17 00:00:00 2001
From: dearblue <dearblue@users.osdn.me>
Date: Sat, 30 Jul 2022 22:31:58 +0900
Subject: [PATCH] Check `MRB_GC_RED` with `mrb_gc_protect()`

When `gc_protect()` is called from `mrb_obj_alloc()`, unnecessary overhead is eliminated.
---
 src/gc.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/gc.c b/src/gc.c
index a3d496162..204c56e6b 100644
--- a/src/gc.c
+++ b/src/gc.c
@@ -449,7 +449,6 @@ mrb_gc_destroy(mrb_state *mrb, mrb_gc *gc)
 static void
 gc_protect(mrb_state *mrb, mrb_gc *gc, struct RBasic *p)
 {
-  if (is_red(p)) return;
 #ifdef MRB_GC_FIXED_ARENA
   if (gc->arena_idx >= MRB_GC_ARENA_SIZE) {
     /* arena overflow error */
@@ -472,7 +471,9 @@ MRB_API void
 mrb_gc_protect(mrb_state *mrb, mrb_value obj)
 {
   if (mrb_immediate_p(obj)) return;
-  gc_protect(mrb, &mrb->gc, mrb_basic_ptr(obj));
+  struct RBasic *p = mrb_basic_ptr(obj);
+  if (is_red(p)) return;
+  gc_protect(mrb, &mrb->gc, p);
 }
 
 #define GC_ROOT_SYM MRB_SYM(_gc_root_)