| … | |
… | |
| 41 | #endif |
41 | #endif |
| 42 | |
42 | |
| 43 | // put into ifs if you are very sure that the expression |
43 | // put into ifs if you are very sure that the expression |
| 44 | // is mostly true or mosty false. note that these return |
44 | // is mostly true or mosty false. note that these return |
| 45 | // booleans, not the expression. |
45 | // booleans, not the expression. |
| 46 | #define expect_false(expr) expect ((expr) != 0, 0) |
46 | #define expect_false(expr) expect ((expr) ? 1 : 0, 0) |
| 47 | #define expect_true(expr) expect ((expr) != 0, 1) |
47 | #define expect_true(expr) expect ((expr) ? 1 : 0, 1) |
| 48 | |
48 | |
| 49 | #include <pthread.h> |
49 | #include <pthread.h> |
| 50 | |
50 | |
| 51 | #include <cstddef> |
51 | #include <cstddef> |
| 52 | #include <cmath> |
52 | #include <cmath> |
| … | |
… | |
| 540 | |
540 | |
| 541 | struct str_hash |
541 | struct str_hash |
| 542 | { |
542 | { |
| 543 | std::size_t operator ()(const char *s) const |
543 | std::size_t operator ()(const char *s) const |
| 544 | { |
544 | { |
| 545 | unsigned long hash = 0; |
545 | #if 0 |
|
|
546 | uint32_t hash = 0; |
| 546 | |
547 | |
| 547 | /* use the one-at-a-time hash function, which supposedly is |
548 | /* use the one-at-a-time hash function, which supposedly is |
| 548 | * better than the djb2-like one used by perl5.005, but |
549 | * better than the djb2-like one used by perl5.005, but |
| 549 | * certainly is better then the bug used here before. |
550 | * certainly is better then the bug used here before. |
| 550 | * see http://burtleburtle.net/bob/hash/doobs.html |
551 | * see http://burtleburtle.net/bob/hash/doobs.html |
| … | |
… | |
| 557 | } |
558 | } |
| 558 | |
559 | |
| 559 | hash += hash << 3; |
560 | hash += hash << 3; |
| 560 | hash ^= hash >> 11; |
561 | hash ^= hash >> 11; |
| 561 | hash += hash << 15; |
562 | hash += hash << 15; |
|
|
563 | #else |
|
|
564 | // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/) |
|
|
565 | // it is about twice as fast as the one-at-a-time one, |
|
|
566 | // with good distribution. |
|
|
567 | // FNV-1a is faster on many cpus because the multiplication |
|
|
568 | // runs concurrent with the looping logic. |
|
|
569 | uint32_t hash = 2166136261; |
|
|
570 | |
|
|
571 | while (*s) |
|
|
572 | hash = (hash ^ *s++) * 16777619; |
|
|
573 | #endif |
| 562 | |
574 | |
| 563 | return hash; |
575 | return hash; |
| 564 | } |
576 | } |
| 565 | }; |
577 | }; |
| 566 | |
578 | |
