'luaV_fastget' only treats the real fast case (table with a non-nil

value at given key, so that it does not need to check metamethods)
This commit is contained in:
Roberto Ierusalimschy
2016-01-05 14:07:21 -02:00
parent a272fa66f0
commit 1a44e82200
3 changed files with 67 additions and 55 deletions

31
lvm.h
View File

@@ -1,5 +1,5 @@
/*
** $Id: lvm.h,v 2.38 2015/08/03 20:40:26 roberto Exp roberto $
** $Id: lvm.h,v 2.39 2015/09/09 13:44:07 roberto Exp roberto $
** Lua virtual machine
** See Copyright Notice in lua.h
*/
@@ -49,25 +49,24 @@
/*
** fast track for 'gettable': 1 means 'aux' points to resulted value;
** 0 means 'aux' is metamethod (if 't' is a table) or NULL. 'f' is
** the raw get function to use.
** fast track for 'gettable': if 't' is a table and 't[k]' is not nil,
** return 1 with 'slot' pointing to 't[k]' (final result). Otherwise,
** return 0 (meaning it will have to check metamethod) with 'slot'
** pointing to a nil 't[k]' (if 't' is a table) or NULL (otherwise).
** 'f' is the raw get function to use.
*/
#define luaV_fastget(L,t,k,aux,f) \
#define luaV_fastget(L,t,k,slot,f) \
(!ttistable(t) \
? (aux = NULL, 0) /* not a table; 'aux' is NULL and result is 0 */ \
: (aux = f(hvalue(t), k), /* else, do raw access */ \
!ttisnil(aux) ? 1 /* result not nil? 'aux' has it */ \
: (aux = fasttm(L, hvalue(t)->metatable, TM_INDEX), /* get metamethod */\
aux != NULL ? 0 /* has metamethod? must call it */ \
: (aux = luaO_nilobject, 1)))) /* else, final result is nil */
? (slot = NULL, 0) /* not a table; 'slot' is NULL and result is 0 */ \
: (slot = f(hvalue(t), k), /* else, do raw access */ \
!ttisnil(slot))) /* result not nil? */
/*
** standard implementation for 'gettable'
*/
#define luaV_gettable(L,t,k,v) { const TValue *aux; \
if (luaV_fastget(L,t,k,aux,luaH_get)) { setobj2s(L, v, aux); } \
else luaV_finishget(L,t,k,v,aux); }
#define luaV_gettable(L,t,k,v) { const TValue *slot; \
if (luaV_fastget(L,t,k,slot,luaH_get)) { setobj2s(L, v, slot); } \
else luaV_finishget(L,t,k,v,slot); }
/*
@@ -100,9 +99,9 @@ LUAI_FUNC int luaV_lessequal (lua_State *L, const TValue *l, const TValue *r);
LUAI_FUNC int luaV_tonumber_ (const TValue *obj, lua_Number *n);
LUAI_FUNC int luaV_tointeger (const TValue *obj, lua_Integer *p, int mode);
LUAI_FUNC void luaV_finishget (lua_State *L, const TValue *t, TValue *key,
StkId val, const TValue *tm);
StkId val, const TValue *slot);
LUAI_FUNC void luaV_finishset (lua_State *L, const TValue *t, TValue *key,
StkId val, const TValue *oldval);
StkId val, const TValue *slot);
LUAI_FUNC void luaV_finishOp (lua_State *L);
LUAI_FUNC void luaV_execute (lua_State *L);
LUAI_FUNC void luaV_concat (lua_State *L, int total);