From 2331e1beec01babf78ca09fea8701b5bb3c78d4c Mon Sep 17 00:00:00 2001
From: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Thu, 6 Apr 2017 10:08:56 -0300
Subject: [PATCH] small changes in 'luaC_upvalbarrier'

---
 lapi.c  | 10 +++++-----
 lfunc.c |  9 +++++----
 lgc.c   |  8 +++-----
 lgc.h   |  8 ++++----
 lvm.c   |  4 ++--
 5 files changed, 19 insertions(+), 20 deletions(-)

diff --git a/lapi.c b/lapi.c
index 494fce75..25ed81fd 100644
--- a/lapi.c
+++ b/lapi.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lapi.c,v 2.259 2016/02/29 14:27:14 roberto Exp roberto $
+** $Id: lapi.c,v 2.260 2017/02/23 21:07:34 roberto Exp roberto $
 ** Lua API
 ** See Copyright Notice in lua.h
 */
@@ -1004,7 +1004,7 @@ LUA_API int lua_load (lua_State *L, lua_Reader reader, void *data,
       const TValue *gt = luaH_getint(reg, LUA_RIDX_GLOBALS);
       /* set global table as 1st upvalue of 'f' (may be LUA_ENV) */
       setobj(L, f->upvals[0]->v, gt);
-      luaC_upvalbarrier(L, f->upvals[0]);
+      luaC_upvalbarrier(L, f->upvals[0], gt);
     }
   }
   lua_unlock(L);
@@ -1253,8 +1253,8 @@ LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n) {
   if (name) {
     L->top--;
     setobj(L, val, L->top);
-    if (owner) { luaC_barrier(L, owner, L->top); }
-    else if (uv) { luaC_upvalbarrier(L, uv); }
+    if (owner) { luaC_barrier(L, owner, val); }
+    else if (uv) { luaC_upvalbarrier(L, uv, val); }
   }
   lua_unlock(L);
   return name;
@@ -1300,7 +1300,7 @@ LUA_API void lua_upvaluejoin (lua_State *L, int fidx1, int n1,
   *up1 = *up2;
   (*up1)->refcount++;
   if (upisopen(*up1)) (*up1)->u.open.touched = 1;
-  luaC_upvalbarrier(L, *up1);
+  luaC_upvalbarrier(L, *up1, (*up1)->v);
 }
 
 
diff --git a/lfunc.c b/lfunc.c
index 4c10230e..0f839e7c 100644
--- a/lfunc.c
+++ b/lfunc.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lfunc.c,v 2.44 2014/10/25 11:50:46 roberto Exp roberto $
+** $Id: lfunc.c,v 2.45 2014/11/02 19:19:04 roberto Exp roberto $
 ** Auxiliary functions to manipulate prototypes and closures
 ** See Copyright Notice in lua.h
 */
@@ -88,9 +88,10 @@ void luaF_close (lua_State *L, StkId level) {
     if (uv->refcount == 0)  /* no references? */
       luaM_free(L, uv);  /* free upvalue */
     else {
-      setobj(L, &uv->u.value, uv->v);  /* move value to upvalue slot */
-      uv->v = &uv->u.value;  /* now current value lives here */
-      luaC_upvalbarrier(L, uv);
+      TValue *slot = &uv->u.value;  /* new position for value */
+      setobj(L, slot, uv->v);  /* move value to upvalue slot */
+      uv->v = slot;  /* now current value lives here */
+      luaC_upvalbarrier(L, uv, slot);
     }
   }
 }
diff --git a/lgc.c b/lgc.c
index 8d185cd7..73114300 100644
--- a/lgc.c
+++ b/lgc.c
@@ -186,13 +186,11 @@ void luaC_barrierback_ (lua_State *L, Table *t) {
 ** closures pointing to it. So, we assume that the object being assigned
 ** must be marked.
 */
-void luaC_upvalbarrier_ (lua_State *L, UpVal *uv) {
+void luaC_upvalbarrier_ (lua_State *L, GCObject *o) {
   global_State *g = G(L);
-  GCObject *o = gcvalue(uv->v);
-  if (keepinvariant(g)) {
+  if (keepinvariant(g) && !isold(o)) {
     markobject(g, o);
-    if (!isold(o))
-      setage(o, G_OLD0);
+    setage(o, G_OLD0);
   }
 }
 
diff --git a/lgc.h b/lgc.h
index 158c0e38..c5dfcf2e 100644
--- a/lgc.h
+++ b/lgc.h
@@ -153,9 +153,9 @@
 	(isblack(p) && iswhite(o)) ? \
 	luaC_barrier_(L,obj2gco(p),obj2gco(o)) : cast_void(0))
 
-#define luaC_upvalbarrier(L,uv) ( \
-	(iscollectable((uv)->v) && !upisopen(uv)) ? \
-         luaC_upvalbarrier_(L,uv) : cast_void(0))
+#define luaC_upvalbarrier(L,uv,x) ( \
+	(iscollectable(x) && !upisopen(uv)) ? \
+         luaC_upvalbarrier_(L,gcvalue(x)) : cast_void(0))
 
 LUAI_FUNC void luaC_fix (lua_State *L, GCObject *o);
 LUAI_FUNC void luaC_freeallobjects (lua_State *L);
@@ -165,7 +165,7 @@ LUAI_FUNC void luaC_fullgc (lua_State *L, int isemergency);
 LUAI_FUNC GCObject *luaC_newobj (lua_State *L, int tt, size_t sz);
 LUAI_FUNC void luaC_barrier_ (lua_State *L, GCObject *o, GCObject *v);
 LUAI_FUNC void luaC_barrierback_ (lua_State *L, Table *o);
-LUAI_FUNC void luaC_upvalbarrier_ (lua_State *L, UpVal *uv);
+LUAI_FUNC void luaC_upvalbarrier_ (lua_State *L, GCObject *o);
 LUAI_FUNC void luaC_checkfinalizer (lua_State *L, GCObject *o, Table *mt);
 LUAI_FUNC void luaC_upvdeccount (lua_State *L, UpVal *uv);
 LUAI_FUNC void luaC_changemode (lua_State *L, int newmode);
diff --git a/lvm.c b/lvm.c
index 3709d77a..81b2a481 100644
--- a/lvm.c
+++ b/lvm.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lvm.c,v 2.267 2016/01/05 16:07:21 roberto Exp roberto $
+** $Id: lvm.c,v 2.268 2016/02/05 19:59:14 roberto Exp roberto $
 ** Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -855,7 +855,7 @@ void luaV_execute (lua_State *L) {
       vmcase(OP_SETUPVAL) {
         UpVal *uv = cl->upvals[GETARG_B(i)];
         setobj(L, uv->v, ra);
-        luaC_upvalbarrier(L, uv);
+        luaC_upvalbarrier(L, uv, ra);
         vmbreak;
       }
       vmcase(OP_SETTABLE) {