From 07f861385eaa0073af98261ae2919ad9bbce813c Mon Sep 17 00:00:00 2001
From: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Mon, 15 Apr 2013 12:44:46 -0300
Subject: first steps in the support of integers: basic representation + table
 indexing + basic API ops (tointeger/pushinteger) + equality + a few extra
 stuff

---
 ltable.c | 63 +++++++++++++++++++++++++++++++++++++++------------------------
 1 file changed, 39 insertions(+), 24 deletions(-)

(limited to 'ltable.c')

diff --git a/ltable.c b/ltable.c
index 8c971b27..7147f6fe 100644
--- a/ltable.c
+++ b/ltable.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ltable.c,v 2.71 2012/05/23 15:37:09 roberto Exp roberto $
+** $Id: ltable.c,v 2.71 2012/05/23 15:37:09 roberto Exp $
 ** Lua tables (hash)
 ** See Copyright Notice in lua.h
 */
@@ -52,6 +52,7 @@
 
 #define hashstr(t,str)		hashpow2(t, (str)->tsv.hash)
 #define hashboolean(t,p)	hashpow2(t, p)
+#define hashint(t,i)		hashpow2(t, i)
 
 
 /*
@@ -96,8 +97,12 @@ static Node *hashnum (const Table *t, lua_Number n) {
 */
 static Node *mainposition (const Table *t, const TValue *key) {
   switch (ttype(key)) {
-    case LUA_TNUMBER:
-      return hashnum(t, nvalue(key));
+    case LUA_TNUMINT:
+      return hashint(t, ivalue(key));
+    case LUA_TNUMFLT:
+      return hashnum(t, fltvalue(key));
+    case LUA_TSHRSTR:
+      return hashstr(t, rawtsvalue(key));
     case LUA_TLNGSTR: {
       TString *s = rawtsvalue(key);
       if (s->tsv.extra == 0) {  /* no hash? */
@@ -106,8 +111,6 @@ static Node *mainposition (const Table *t, const TValue *key) {
       }
       return hashstr(t, rawtsvalue(key));
     }
-    case LUA_TSHRSTR:
-      return hashstr(t, rawtsvalue(key));
     case LUA_TBOOLEAN:
       return hashboolean(t, bvalue(key));
     case LUA_TLIGHTUSERDATA:
@@ -120,19 +123,24 @@ static Node *mainposition (const Table *t, const TValue *key) {
 }
 
 
+static int numisint (lua_Number n, int *p) {
+  int k;
+  lua_number2int(k, n);
+  if (luai_numeq(cast_num(k), n)) {  /* 'k' is int? */
+    *p = k;
+    return 1;
+  }
+  return 0;
+}
+
+
 /*
 ** returns the index for `key' if `key' is an appropriate key to live in
 ** the array part of the table, -1 otherwise.
 */
 static int arrayindex (const TValue *key) {
-  if (ttisnumber(key)) {
-    lua_Number n = nvalue(key);
-    int k;
-    lua_number2int(k, n);
-    if (luai_numeq(cast_num(k), n))
-      return k;
-  }
-  return -1;  /* `key' did not match some condition */
+  if (ttisinteger(key)) return ivalue(key);
+  else return -1;  /* `key' did not match some condition */
 }
 
 
@@ -170,7 +178,7 @@ int luaH_next (lua_State *L, Table *t, StkId key) {
   int i = findindex(L, t, key);  /* find original element */
   for (i++; i < t->sizearray; i++) {  /* try first array part */
     if (!ttisnil(&t->array[i])) {  /* a non-nil value? */
-      setnvalue(key, cast_num(i+1));
+      setivalue(key, i + 1);
       setobj2s(L, key+1, &t->array[i]);
       return 1;
     }
@@ -404,9 +412,18 @@ static Node *getfreepos (Table *t) {
 */
 TValue *luaH_newkey (lua_State *L, Table *t, const TValue *key) {
   Node *mp;
+  TValue aux;
   if (ttisnil(key)) luaG_runerror(L, "table index is nil");
-  else if (ttisnumber(key) && luai_numisnan(L, nvalue(key)))
-    luaG_runerror(L, "table index is NaN");
+  else if (ttisfloat(key)) {
+    lua_Number n = fltvalue(key);
+    int k;
+    if (luai_numisnan(L, n))
+      luaG_runerror(L, "table index is NaN");
+    if (numisint(n, &k)) {  /* index is int? */
+      setivalue(&aux, k); 
+      key = &aux;  /* insert it as an integer */
+    }
+  }
   mp = mainposition(t, key);
   if (!ttisnil(gval(mp)) || isdummy(mp)) {  /* main position is taken? */
     Node *othern;
@@ -448,10 +465,9 @@ const TValue *luaH_getint (Table *t, int key) {
   if (cast(unsigned int, key-1) < cast(unsigned int, t->sizearray))
     return &t->array[key-1];
   else {
-    lua_Number nk = cast_num(key);
-    Node *n = hashnum(t, nk);
+    Node *n = hashint(t, key);
     do {  /* check whether `key' is somewhere in the chain */
-      if (ttisnumber(gkey(n)) && luai_numeq(nvalue(gkey(n)), nk))
+      if (ttisinteger(gkey(n)) && ivalue(gkey(n)) == key)
         return gval(n);  /* that's it */
       else n = gnext(n);
     } while (n);
@@ -481,12 +497,11 @@ const TValue *luaH_getstr (Table *t, TString *key) {
 const TValue *luaH_get (Table *t, const TValue *key) {
   switch (ttype(key)) {
     case LUA_TSHRSTR: return luaH_getstr(t, rawtsvalue(key));
+    case LUA_TNUMINT: return luaH_getint(t, ivalue(key));
     case LUA_TNIL: return luaO_nilobject;
-    case LUA_TNUMBER: {
+    case LUA_TNUMFLT: {
       int k;
-      lua_Number n = nvalue(key);
-      lua_number2int(k, n);
-      if (luai_numeq(cast_num(k), n)) /* index is int? */
+      if (numisint(fltvalue(key), &k)) /* index is int? */
         return luaH_getint(t, k);  /* use specialized version */
       /* else go through */
     }
@@ -522,7 +537,7 @@ void luaH_setint (lua_State *L, Table *t, int key, TValue *value) {
     cell = cast(TValue *, p);
   else {
     TValue k;
-    setnvalue(&k, cast_num(key));
+    setivalue(&k, key);
     cell = luaH_newkey(L, t, &k);
   }
   setobj2t(L, cell, value);
-- 
cgit v1.2.3-55-g6feb