long strings are created directly in final position when possible

(instead of using an auxiliar buffer to first create the string
and then allocate the final string and copy result there)

1 files changed, 13 insertions, 7 deletions

diff --git a/lstring.c b/lstring.c
index c53325d0..588ee546 100644
--- a/lstring.c
+++ b/lstring.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lstring.c,v 2.49 2015/06/01 16:34:37 roberto Exp roberto $
+** $Id: lstring.c,v 2.50 2015/06/18 14:20:32 roberto Exp roberto $
 ** String table (keeps all strings handled by Lua)
 ** See Copyright Notice in lua.h
 */
@@ -119,8 +119,7 @@ void luaS_init (lua_State *L) {
 /*
 ** creates a new string object
 */
-static TString *createstrobj (lua_State *L, const char *str, size_t l,
-                              int tag, unsigned int h) {
+static TString *createstrobj (lua_State *L, size_t l, int tag, unsigned int h) {
   TString *ts;
   GCObject *o;
   size_t totalsize;  /* total size of TString object */
@@ -129,12 +128,18 @@ static TString *createstrobj (lua_State *L, const char *str, size_t l,
   ts = gco2ts(o);
   ts->hash = h;
   ts->extra = 0;
-  memcpy(getaddrstr(ts), str, l * sizeof(char));
   getaddrstr(ts)[l] = '\0';  /* ending 0 */
   return ts;
 }
 
 
+TString *luaS_createlngstrobj (lua_State *L, size_t l) {
+  TString *ts = createstrobj(L, l, LUA_TLNGSTR, G(L)->seed);
+  ts->u.lnglen = l;
+  return ts;
+}
+
+
 void luaS_remove (lua_State *L, TString *ts) {
   stringtable *tb = &G(L)->strt;
   TString **p = &tb->hash[lmod(ts->hash, tb->size)];
@@ -166,7 +171,8 @@ static TString *internshrstr (lua_State *L, const char *str, size_t l) {
     luaS_resize(L, g->strt.size * 2);
     list = &g->strt.hash[lmod(h, g->strt.size)];  /* recompute with new size */
   }
-  ts = createstrobj(L, str, l, LUA_TSHRSTR, h);
+  ts = createstrobj(L, l, LUA_TSHRSTR, h);
+  memcpy(getaddrstr(ts), str, l * sizeof(char));
   ts->shrlen = cast_byte(l);
   ts->u.hnext = *list;
   *list = ts;
@@ -185,8 +191,8 @@ TString *luaS_newlstr (lua_State *L, const char *str, size_t l) {
     TString *ts;
     if (l >= (MAX_SIZE - sizeof(TString))/sizeof(char))
       luaM_toobig(L);
-    ts = createstrobj(L, str, l, LUA_TLNGSTR, G(L)->seed);
-    ts->u.lnglen = l;
+    ts = luaS_createlngstrobj(L, l);
+    memcpy(getaddrstr(ts), str, l * sizeof(char));
     return ts;
   }
 }