diff options
Diffstat (limited to 'lstring.c')
-rw-r--r-- | lstring.c | 20 |
1 files changed, 4 insertions, 16 deletions
@@ -23,16 +23,6 @@ | |||
23 | 23 | ||
24 | 24 | ||
25 | /* | 25 | /* |
26 | ** Lua will use at most ~(2^LUAI_HASHLIMIT) bytes from a long string to | ||
27 | ** compute its hash | ||
28 | */ | ||
29 | #if !defined(LUAI_HASHLIMIT) | ||
30 | #define LUAI_HASHLIMIT 5 | ||
31 | #endif | ||
32 | |||
33 | |||
34 | |||
35 | /* | ||
36 | ** Maximum size for string table. | 26 | ** Maximum size for string table. |
37 | */ | 27 | */ |
38 | #define MAXSTRTB cast_int(luaM_limitN(MAX_INT, TString*)) | 28 | #define MAXSTRTB cast_int(luaM_limitN(MAX_INT, TString*)) |
@@ -50,10 +40,9 @@ int luaS_eqlngstr (TString *a, TString *b) { | |||
50 | } | 40 | } |
51 | 41 | ||
52 | 42 | ||
53 | unsigned int luaS_hash (const char *str, size_t l, unsigned int seed, | 43 | unsigned int luaS_hash (const char *str, size_t l, unsigned int seed) { |
54 | size_t step) { | ||
55 | unsigned int h = seed ^ cast_uint(l); | 44 | unsigned int h = seed ^ cast_uint(l); |
56 | for (; l >= step; l -= step) | 45 | for (; l > 0; l--) |
57 | h ^= ((h<<5) + (h>>2) + cast_byte(str[l - 1])); | 46 | h ^= ((h<<5) + (h>>2) + cast_byte(str[l - 1])); |
58 | return h; | 47 | return h; |
59 | } | 48 | } |
@@ -63,8 +52,7 @@ unsigned int luaS_hashlongstr (TString *ts) { | |||
63 | lua_assert(ts->tt == LUA_VLNGSTR); | 52 | lua_assert(ts->tt == LUA_VLNGSTR); |
64 | if (ts->extra == 0) { /* no hash? */ | 53 | if (ts->extra == 0) { /* no hash? */ |
65 | size_t len = ts->u.lnglen; | 54 | size_t len = ts->u.lnglen; |
66 | size_t step = (len >> LUAI_HASHLIMIT) + 1; | 55 | ts->hash = luaS_hash(getstr(ts), len, ts->hash); |
67 | ts->hash = luaS_hash(getstr(ts), len, ts->hash, step); | ||
68 | ts->extra = 1; /* now it has its hash */ | 56 | ts->extra = 1; /* now it has its hash */ |
69 | } | 57 | } |
70 | return ts->hash; | 58 | return ts->hash; |
@@ -201,7 +189,7 @@ static TString *internshrstr (lua_State *L, const char *str, size_t l) { | |||
201 | TString *ts; | 189 | TString *ts; |
202 | global_State *g = G(L); | 190 | global_State *g = G(L); |
203 | stringtable *tb = &g->strt; | 191 | stringtable *tb = &g->strt; |
204 | unsigned int h = luaS_hash(str, l, g->seed, 1); | 192 | unsigned int h = luaS_hash(str, l, g->seed); |
205 | TString **list = &tb->hash[lmod(h, tb->size)]; | 193 | TString **list = &tb->hash[lmod(h, tb->size)]; |
206 | lua_assert(str != NULL); /* otherwise 'memcmp'/'memcpy' are undefined */ | 194 | lua_assert(str != NULL); /* otherwise 'memcmp'/'memcpy' are undefined */ |
207 | for (ts = *list; ts != NULL; ts = ts->u.hnext) { | 195 | for (ts = *list; ts != NULL; ts = ts->u.hnext) { |