small optimizations for table access

This commit is contained in:
Roberto Ierusalimschy 2000-04-25 13:55:09 -03:00
parent b9c98cd4d9
commit 534c3a64d3
5 changed files with 57 additions and 31 deletions

View File

@ -1,5 +1,5 @@
/*
** $Id: lbuiltin.c,v 1.105 2000/04/14 17:44:20 roberto Exp roberto $
** $Id: lbuiltin.c,v 1.106 2000/04/17 19:23:12 roberto Exp roberto $
** Built-in functions
** See Copyright Notice in lua.h
*/
@ -321,7 +321,7 @@ void luaB_call (lua_State *L) {
/* push arg[1...n] */
luaD_checkstack(L, narg);
for (i=0; i<narg; i++)
*(L->top++) = *luaH_getint(L, arg, i+1);
*(L->top++) = *luaH_getnum(arg, i+1);
status = lua_callfunction(L, f);
if (err != LUA_NOOBJECT) { /* restore old error method */
lua_pushobject(L, err);
@ -434,7 +434,7 @@ void luaB_foreachi (lua_State *L) {
for (i=1; i<=n; i++) {
*(L->top++) = *f;
ttype(L->top) = TAG_NUMBER; nvalue(L->top++) = i;
*(L->top++) = *luaH_getint(L, t, i);
*(L->top++) = *luaH_getnum(t, i);
luaD_call(L, L->top-3, 1);
if (ttype(L->top-1) != TAG_NIL)
return;
@ -513,7 +513,7 @@ void luaB_tremove (lua_State *L) {
int n = (int)getnarg(L, a);
int pos = luaL_opt_int(L, 2, n);
if (n <= 0) return; /* table is "empty" */
luaA_pushobject(L, luaH_getint(L, a, pos)); /* result = a[pos] */
luaA_pushobject(L, luaH_getnum(a, pos)); /* result = a[pos] */
for ( ;pos<n; pos++)
luaH_move(L, a, pos+1, pos); /* a[pos] = a[pos+1] */
luaV_setn(L, a, n-1); /* a.n = n-1 */
@ -529,7 +529,7 @@ void luaB_tremove (lua_State *L) {
static void swap (lua_State *L, Hash *a, int i, int j) {
TObject temp;
temp = *luaH_getint(L, a, i);
temp = *luaH_getnum(a, i);
luaH_move(L, a, j, i);
luaH_setint(L, a, j, &temp);
}
@ -556,26 +556,26 @@ static void auxsort (lua_State *L, Hash *a, int l, int u, lua_Object f) {
while (l < u) { /* for tail recursion */
int i, j;
/* sort elements a[l], a[(l+u)/2] and a[u] */
if (sort_comp(L, f, luaH_getint(L, a, u), luaH_getint(L, a, l)))
if (sort_comp(L, f, luaH_getnum(a, u), luaH_getnum(a, l)))
swap(L, a, l, u); /* a[u]<a[l] */
if (u-l == 1) break; /* only 2 elements */
i = (l+u)/2;
*P = *luaH_getint(L, a, i); /* P = a[i] */
if (sort_comp(L, f, P, luaH_getint(L, a, l))) /* a[i]<a[l]? */
*P = *luaH_getnum(a, i); /* P = a[i] */
if (sort_comp(L, f, P, luaH_getnum(a, l))) /* a[i]<a[l]? */
swap(L, a, l, i);
else if (sort_comp(L, f, luaH_getint(L, a, u), P)) /* a[u]<a[i]? */
else if (sort_comp(L, f, luaH_getnum(a, u), P)) /* a[u]<a[i]? */
swap(L, a, i, u);
if (u-l == 2) break; /* only 3 elements */
*P = *luaH_getint(L, a, i); /* save pivot on stack (GC) */
*P = *luaH_getnum(a, i); /* save pivot on stack (GC) */
swap(L, a, i, u-1); /* put median element as pivot (a[u-1]) */
/* a[l] <= P == a[u-1] <= a[u], only needs to sort from l+1 to u-2 */
i = l; j = u-1;
for (;;) { /* invariant: a[l..i] <= P <= a[j..u] */
/* repeat i++ until a[i] >= P */
while (sort_comp(L, f, luaH_getint(L, a, ++i), P))
while (sort_comp(L, f, luaH_getnum(a, ++i), P))
if (i>u) lua_error(L, "invalid order function for sorting");
/* repeat j-- until a[j] <= P */
while (sort_comp(L, f, P, luaH_getint(L, a, --j)))
while (sort_comp(L, f, P, luaH_getnum(a, --j)))
if (j<l) lua_error(L, "invalid order function for sorting");
if (j<i) break;
swap(L, a, i, j);

View File

@ -1,5 +1,5 @@
/*
** $Id: lobject.c,v 1.35 2000/03/29 20:19:20 roberto Exp roberto $
** $Id: lobject.c,v 1.36 2000/03/31 16:28:45 roberto Exp roberto $
** Some generic functions over Lua objects
** See Copyright Notice in lua.h
*/
@ -32,7 +32,8 @@ unsigned long luaO_power2 (unsigned long n) {
}
int luaO_equalval (const TObject *t1, const TObject *t2) {
int luaO_equalObj (const TObject *t1, const TObject *t2) {
if (ttype(t1) != ttype(t2)) return 0;
switch (ttype(t1)) {
case TAG_NUMBER:
return nvalue(t1) == nvalue(t2);

View File

@ -1,5 +1,5 @@
/*
** $Id: lobject.h,v 1.59 2000/03/31 16:28:45 roberto Exp roberto $
** $Id: lobject.h,v 1.60 2000/04/10 19:20:24 roberto Exp roberto $
** Type definitions for Lua objects
** See Copyright Notice in lua.h
*/
@ -180,8 +180,7 @@ extern const TObject luaO_nilobject;
unsigned long luaO_power2 (unsigned long n);
#define luaO_equalObj(t1,t2) (ttype(t1) == ttype(t2) && luaO_equalval(t1,t2))
int luaO_equalval (const TObject *t1, const TObject *t2);
int luaO_equalObj (const TObject *t1, const TObject *t2);
int luaO_redimension (lua_State *L, int oldsize);
int luaO_str2d (const char *s, Number *result);

View File

@ -1,5 +1,5 @@
/*
** $Id: ltable.c,v 1.38 2000/03/29 20:19:20 roberto Exp roberto $
** $Id: ltable.c,v 1.39 2000/03/31 16:28:45 roberto Exp roberto $
** Lua tables (hash)
** See Copyright Notice in lua.h
*/
@ -60,11 +60,12 @@ Node *luaH_mainposition (const Hash *t, const TObject *key) {
}
LUA_ASSERT(L, h%(unsigned int)t->size == (h&((unsigned int)t->size-1)),
"a&(x-1) == a%x, for x power of 2");
return &t->node[h&((unsigned int)t->size-1)];
return &t->node[h&(t->size-1)];
}
const TObject *luaH_get (lua_State *L, const Hash *t, const TObject *key) {
static const TObject *luaH_getany (lua_State *L, const Hash *t,
const TObject *key) {
Node *n = luaH_mainposition(t, key);
if (!n)
lua_error(L, "unexpected type to index table");
@ -77,6 +78,39 @@ const TObject *luaH_get (lua_State *L, const Hash *t, const TObject *key) {
}
/* specialized version for numbers */
const TObject *luaH_getnum (const Hash *t, Number key) {
Node *n = &t->node[(unsigned long)(long)key&(t->size-1)];
do {
if (ttype(&n->key) == TAG_NUMBER && nvalue(&n->key) == key)
return &n->val;
n = n->next;
} while (n);
return &luaO_nilobject; /* key not found */
}
/* specialized version for strings */
static const TObject *luaH_getstr (const Hash *t, TString *key) {
Node *n = &t->node[key->hash&(t->size-1)];
do {
if (ttype(&n->key) == TAG_STRING && tsvalue(&n->key) == key)
return &n->val;
n = n->next;
} while (n);
return &luaO_nilobject; /* key not found */
}
const TObject *luaH_get (lua_State *L, const Hash *t, const TObject *key) {
switch (ttype(key)) {
case TAG_NUMBER: return luaH_getnum(t, nvalue(key));
case TAG_STRING: return luaH_getstr(t, tsvalue(key));
default: return luaH_getany(L, t, key);
}
}
int luaH_pos (lua_State *L, const Hash *t, const TObject *key) {
const TObject *v = luaH_get(L, t, key);
return (v == &luaO_nilobject) ? -1 : /* key not found */
@ -214,11 +248,3 @@ void luaH_setint (lua_State *L, Hash *t, int key, const TObject *val) {
luaH_set(L, t, &index, val);
}
const TObject *luaH_getint (lua_State *L, const Hash *t, int key) {
TObject index;
ttype(&index) = TAG_NUMBER;
nvalue(&index) = key;
return luaH_get(L, t, &index);
}

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@ -1,5 +1,5 @@
/*
** $Id: ltable.h,v 1.17 1999/11/23 13:58:02 roberto Exp roberto $
** $Id: ltable.h,v 1.18 1999/12/07 12:05:34 roberto Exp roberto $
** Lua tables (hash)
** See Copyright Notice in lua.h
*/
@ -14,7 +14,7 @@
#define key(n) (&(n)->key)
#define val(n) (&(n)->val)
#define luaH_move(L, t,from,to) (luaH_setint(L, t, to, luaH_getint(L, t, from)))
#define luaH_move(L, t,from,to) (luaH_setint(L, t, to, luaH_getnum(t, from)))
Hash *luaH_new (lua_State *L, int nhash);
void luaH_free (lua_State *L, Hash *t);
@ -22,7 +22,7 @@ const TObject *luaH_get (lua_State *L, const Hash *t, const TObject *key);
void luaH_set (lua_State *L, Hash *t, const TObject *key, const TObject *val);
int luaH_pos (lua_State *L, const Hash *t, const TObject *r);
void luaH_setint (lua_State *L, Hash *t, int key, const TObject *val);
const TObject *luaH_getint (lua_State *L, const Hash *t, int key);
const TObject *luaH_getnum (const Hash *t, Number key);
unsigned long luaH_hash (lua_State *L, const TObject *key);
/* exported only for debugging */