From 198be23f36466496228bdbceac2d4b8c01e3c21c Mon Sep 17 00:00:00 2001
From: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Thu, 8 May 2008 12:44:51 -0300
Subject: [PATCH] added structure for local-variable information to allow extra
 checkings if needed

---
 lparser.c |  7 ++++---
 lparser.h | 14 ++++++++++----
 2 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/lparser.c b/lparser.c
index f0debe73..61032552 100644
--- a/lparser.c
+++ b/lparser.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lparser.c,v 2.56 2007/10/25 16:45:47 roberto Exp roberto $
+** $Id: lparser.c,v 2.57 2008/04/02 17:19:22 roberto Exp roberto $
 ** Lua Parser
 ** See Copyright Notice in lua.h
 */
@@ -29,7 +29,7 @@
 
 #define hasmultret(k)		((k) == VCALL || (k) == VVARARG)
 
-#define getlocvar(fs, i)	((fs)->f->locvars[(fs)->actvar[i]])
+#define getlocvar(fs, i)	((fs)->f->locvars[(fs)->actvar[i].idx])
 
 #define luaY_checklimit(fs,v,l,m)	if ((v)>(l)) errorlimit(fs,l,m)
 
@@ -161,8 +161,9 @@ static int registerlocalvar (LexState *ls, TString *varname) {
 
 static void new_localvar (LexState *ls, TString *name, int n) {
   FuncState *fs = ls->fs;
+  int reg = registerlocalvar(ls, name);
   luaY_checklimit(fs, fs->nactvar+n+1, LUAI_MAXVARS, "local variables");
-  fs->actvar[fs->nactvar+n] = cast(unsigned short, registerlocalvar(ls, name));
+  fs->actvar[fs->nactvar+n].idx = cast(unsigned short, reg);
 }
 
 
diff --git a/lparser.h b/lparser.h
index 7e1d487d..0e06b1ad 100644
--- a/lparser.h
+++ b/lparser.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lparser.h,v 1.56 2005/10/03 14:02:40 roberto Exp roberto $
+** $Id: lparser.h,v 1.57 2006/03/09 18:14:31 roberto Exp roberto $
 ** Lua Parser
 ** See Copyright Notice in lua.h
 */
@@ -23,8 +23,8 @@ typedef enum {
   VFALSE,
   VK,		/* info = index of constant in `k' */
   VKNUM,	/* nval = numerical value */
-  VLOCAL,	/* info = local register */
-  VUPVAL,       /* info = index of upvalue in `upvalues' */
+  VLOCAL,	/* info = local register; aux = read only */
+  VUPVAL,       /* info = index of upvalue in 'upvalues'; aux = read only */
   VGLOBAL,	/* info = index of table; aux = index of global name in `k' */
   VINDEXED,	/* info = table register; aux = index register (or `k') */
   VJMP,		/* info = instruction pc */
@@ -34,6 +34,7 @@ typedef enum {
   VVARARG	/* info = instruction pc */
 } expkind;
 
+
 typedef struct expdesc {
   expkind k;
   union {
@@ -51,6 +52,11 @@ typedef struct upvaldesc {
 } upvaldesc;
 
 
+typedef struct vardesc {
+  unsigned short idx;
+} vardesc;
+
+
 struct BlockCnt;  /* defined in lparser.c */
 
 
@@ -71,7 +77,7 @@ typedef struct FuncState {
   short nlocvars;  /* number of elements in `locvars' */
   lu_byte nactvar;  /* number of active local variables */
   upvaldesc upvalues[LUAI_MAXUPVALUES];  /* upvalues */
-  unsigned short actvar[LUAI_MAXVARS];  /* declared-variable stack */
+  vardesc actvar[LUAI_MAXVARS];  /* declared-variable stack */
 } FuncState;