lua

commit d120ec29ca6bae7a8f0040c7a0cee27aca7dd81a
parent 2aff901c932862ccdb32c145d0034c20fe4fc41d
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date:   Thu, 28 Apr 2011 10:59:47 -0300

bug in OP_SELF when method name goes to a register

Diffstat:
M
lcode.c
 | 
14
+++++++-------
M
ldebug.c
 | 
44
++++++++++++++++++++++++++++++++------------

2 files changed, 39 insertions(+), 19 deletions(-)
diff --git a/lcode.c b/lcode.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lcode.c,v 2.52 2011/04/07 18:14:12 roberto Exp roberto $
+** $Id: lcode.c,v 2.53 2011/04/19 16:22:13 roberto Exp roberto $
 ** Code generator for Lua
 ** See Copyright Notice in lua.h
 */
@@ -581,15 +581,15 @@ void luaK_storevar (FuncState *fs, expdesc *var, expdesc *ex) {
 
 
 void luaK_self (FuncState *fs, expdesc *e, expdesc *key) {
-  int func;
+  int ereg;
   luaK_exp2anyreg(fs, e);
+  ereg = e->u.info;  /* register where 'e' was placed */
   freeexp(fs, e);
-  func = fs->freereg;
-  luaK_codeABC(fs, OP_SELF, func, e->u.info, luaK_exp2RK(fs, key));
-  freeexp(fs, key);
-  luaK_reserveregs(fs, 2);
-  e->u.info = func;
+  e->u.info = fs->freereg;  /* base register for op_self */
   e->k = VNONRELOC;
+  luaK_reserveregs(fs, 2);  /* function and 'self' produced by op_self */
+  luaK_codeABC(fs, OP_SELF, e->u.info, ereg, luaK_exp2RK(fs, key));
+  freeexp(fs, key);
 }
 
 
diff --git a/ldebug.c b/ldebug.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ldebug.c,v 2.79 2011/04/18 19:49:13 roberto Exp roberto $
+** $Id: ldebug.c,v 2.80 2011/04/19 16:22:13 roberto Exp roberto $
 ** Debug Interface
 ** See Copyright Notice in lua.h
 */
@@ -284,15 +284,32 @@ LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
 ** =======================================================
 */
 
+static const char *getobjname (lua_State *L, CallInfo *ci, int reg,
+                               const char **name);
 
-static void kname (Proto *p, int c, int reg, const char *what,
-                   const char **name) {
-  if (c == reg && what && *what == 'c')
-    return;  /* index is a constant; name already correct */
-  else if (ISK(c) && ttisstring(&p->k[INDEXK(c)]))
-    *name = svalue(&p->k[INDEXK(c)]);
-  else
-    *name = "?";
+
+/*
+** find a "name" for the RK value 'c'
+*/
+static void kname (lua_State *L, CallInfo *ci, int c, int oreg,
+                   const char *what, const char **name) {
+  if (ISK(c)) {  /* is 'c' a constant? */
+    TValue *kvalue = &ci_func(ci)->l.p->k[INDEXK(c)];
+    if (ttisstring(kvalue)) {  /* literal constant? */
+      *name = svalue(kvalue);  /* it is its own name */
+      return;
+    }
+    /* else no reasonable name found */
+  }
+  else {  /* 'c' is a register */
+    if (c != oreg)  /* not the original register? */
+      what = getobjname(L, ci, c, name); /* search for 'c' */
+    if (what && *what == 'c') {  /* found a constant name? */
+      return;  /* 'name' already filled */
+    }
+    /* else no reasonable name found */
+  }
+  *name = "?";  /* no reasonable name found */
 }
 
 
@@ -328,7 +345,7 @@ static const char *getobjname (lua_State *L, CallInfo *ci, int reg,
           const char *vn = (op == OP_GETTABLE)  /* name of indexed variable */
                            ? luaF_getlocalname(p, t + 1, pc)
                            : getstr(p->upvalues[t].name);
-          kname(p, k, a, what, name);
+          kname(L, ci, k, a, what, name);
           what = (vn && strcmp(vn, LUA_ENV) == 0) ? "global" : "field";
         }
         break;
@@ -363,7 +380,7 @@ static const char *getobjname (lua_State *L, CallInfo *ci, int reg,
       case OP_SELF: {
         if (reg == a) {
           int k = GETARG_C(i);  /* key index */
-          kname(p, k, a, what, name);
+          kname(L, ci, k, a, what, name);
           what = "method";
         }
         break;
@@ -443,7 +460,10 @@ static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name) {
 
 
 
-/* only ANSI way to check whether a pointer points to an array */
+/*
+** only ANSI way to check whether a pointer points to an array
+** (used only for error messages, so efficiency is not a big concern)
+*/
 static int isinstack (CallInfo *ci, const TValue *o) {
   StkId p;
   for (p = ci->u.l.base; p < ci->top; p++)