Simplification in the call to 'constfolding'

lcode.h

@@ -24,19 +24,27 @@
 ** grep "ORDER OPR" if you change these enums  (ORDER OP)
 */
 typedef enum BinOpr {
+  /* arithmetic operators */
   OPR_ADD, OPR_SUB, OPR_MUL, OPR_MOD, OPR_POW,
-  OPR_DIV,
-  OPR_IDIV,
+  OPR_DIV, OPR_IDIV,
+  /* bitwise operators */
   OPR_BAND, OPR_BOR, OPR_BXOR,
   OPR_SHL, OPR_SHR,
+  /* string operator */
   OPR_CONCAT,
+  /* comparison operators */
   OPR_EQ, OPR_LT, OPR_LE,
   OPR_NE, OPR_GT, OPR_GE,
+  /* logical operators */
   OPR_AND, OPR_OR,
   OPR_NOBINOPR
 } BinOpr;
 
 
+/* true if operation is foldable (that is, it is arithmetic or bitwise) */
+#define foldbinop(op)	((op) <= OPR_SHR)
+
+
 #define luaK_codeABC(fs,o,a,b,c)	luaK_codeABCk(fs,o,a,b,c,0)