1/*
2** Table handling.
3** Copyright (C) 2005-2021 Mike Pall. See Copyright Notice in luajit.h
4*/
5
6#ifndef _LJ_TAB_H
7#define _LJ_TAB_H
8
9#include "lj_obj.h"
10
11/* Hash constants. Tuned using a brute force search. */
12#define HASH_BIAS (-0x04c11db7)
13#define HASH_ROT1 14
14#define HASH_ROT2 5
15#define HASH_ROT3 13
16
17/* Scramble the bits of numbers and pointers. */
18static LJ_AINLINE uint32_t hashrot(uint32_t lo, uint32_t hi)
19{
20#if LJ_TARGET_X86ORX64
21 /* Prefer variant that compiles well for a 2-operand CPU. */
22 lo ^= hi; hi = lj_rol(hi, HASH_ROT1);
23 lo -= hi; hi = lj_rol(hi, HASH_ROT2);
24 hi ^= lo; hi -= lj_rol(lo, HASH_ROT3);
25#else
26 lo ^= hi;
27 lo = lo - lj_rol(hi, HASH_ROT1);
28 hi = lo ^ lj_rol(hi, HASH_ROT1 + HASH_ROT2);
29 hi = hi - lj_rol(lo, HASH_ROT3);
30#endif
31 return hi;
32}
33
34#define hsize2hbits(s) ((s) ? ((s)==1 ? 1 : 1+lj_fls((uint32_t)((s)-1))) : 0)
35
36LJ_FUNCA GCtab *lj_tab_new(lua_State *L, uint32_t asize, uint32_t hbits);
37LJ_FUNC GCtab *lj_tab_new_ah(lua_State *L, int32_t a, int32_t h);
38#if LJ_HASJIT
39LJ_FUNC GCtab * LJ_FASTCALL lj_tab_new1(lua_State *L, uint32_t ahsize);
40#endif
41LJ_FUNCA GCtab * LJ_FASTCALL lj_tab_dup(lua_State *L, const GCtab *kt);
42LJ_FUNC void LJ_FASTCALL lj_tab_clear(GCtab *t);
43LJ_FUNC void LJ_FASTCALL lj_tab_free(global_State *g, GCtab *t);
44#if LJ_HASFFI
45LJ_FUNC void lj_tab_rehash(lua_State *L, GCtab *t);
46#endif
47LJ_FUNC void lj_tab_resize(lua_State *L, GCtab *t, uint32_t asize, uint32_t hbits);
48LJ_FUNCA void lj_tab_reasize(lua_State *L, GCtab *t, uint32_t nasize);
49
50/* Caveat: all getters except lj_tab_get() can return NULL! */
51
52LJ_FUNCA cTValue * LJ_FASTCALL lj_tab_getinth(GCtab *t, int32_t key);
53LJ_FUNC cTValue *lj_tab_getstr(GCtab *t, GCstr *key);
54LJ_FUNCA cTValue *lj_tab_get(lua_State *L, GCtab *t, cTValue *key);
55
56/* Caveat: all setters require a write barrier for the stored value. */
57
58LJ_FUNCA TValue *lj_tab_newkey(lua_State *L, GCtab *t, cTValue *key);
59LJ_FUNCA TValue *lj_tab_setinth(lua_State *L, GCtab *t, int32_t key);
60LJ_FUNC TValue *lj_tab_setstr(lua_State *L, GCtab *t, GCstr *key);
61LJ_FUNC TValue *lj_tab_set(lua_State *L, GCtab *t, cTValue *key);
62
63#define inarray(t, key) ((MSize)(key) < (MSize)(t)->asize)
64#define arrayslot(t, i) (&tvref((t)->array)[(i)])
65#define lj_tab_getint(t, key) \
66 (inarray((t), (key)) ? arrayslot((t), (key)) : lj_tab_getinth((t), (key)))
67#define lj_tab_setint(L, t, key) \
68 (inarray((t), (key)) ? arrayslot((t), (key)) : lj_tab_setinth(L, (t), (key)))
69
70LJ_FUNCA int lj_tab_next(lua_State *L, GCtab *t, TValue *key);
71LJ_FUNCA MSize LJ_FASTCALL lj_tab_len(GCtab *t);
72#if LJ_HASJIT
73LJ_FUNC MSize LJ_FASTCALL lj_tab_len_hint(GCtab *t, size_t hint);
74#endif
75
76#endif
77