diff options
Diffstat (limited to 'st.c')
-rw-r--r-- | st.c | 25 |
1 files changed, 21 insertions, 4 deletions
@@ -141,13 +141,30 @@ remove_safe_packed_entry(st_table *table, st_index_t i, st_data_t never) } static st_index_t +next_pow2(st_index_t x) +{ + x |= x >> 1; + x |= x >> 2; + x |= x >> 4; + x |= x >> 8; + x |= x >> 16; +#if SIZEOF_ST_INDEX_T == 8 + x |= x >> 32; +#endif + return x + 1; +} + +static st_index_t new_size(st_index_t size) { - st_index_t i; + st_index_t n; - for (i=3; i<31; i++) { - if ((st_index_t)(1<<i) > size) return 1<<i; - } + if (size && (size & ~(size - 1)) == size) /* already a power-of-two? */ + return size; + + n = next_pow2(size); + if (n > size) + return n; #ifndef NOT_RUBY rb_raise(rb_eRuntimeError, "st_table too big"); #endif |