| … | |
… | |
| 28 | |
28 | |
| 29 | #if __GNUC__ >= 3 |
29 | #if __GNUC__ >= 3 |
| 30 | # define is_constant(c) __builtin_constant_p (c) |
30 | # define is_constant(c) __builtin_constant_p (c) |
| 31 | # define expect(expr,value) __builtin_expect ((expr),(value)) |
31 | # define expect(expr,value) __builtin_expect ((expr),(value)) |
| 32 | # define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality) |
32 | # define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality) |
|
|
33 | # define noinline __attribute__((__noinline__)) |
| 33 | #else |
34 | #else |
| 34 | # define is_constant(c) 0 |
35 | # define is_constant(c) 0 |
| 35 | # define expect(expr,value) (expr) |
36 | # define expect(expr,value) (expr) |
| 36 | # define prefetch(addr,rw,locality) |
37 | # define prefetch(addr,rw,locality) |
|
|
38 | # define noinline |
| 37 | #endif |
39 | #endif |
| 38 | |
40 | |
| 39 | #if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4) |
41 | #if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4) |
| 40 | # define decltype(x) typeof(x) |
42 | # define decltype(x) typeof(x) |
| 41 | #endif |
43 | #endif |
| 42 | |
44 | |
| 43 | // put into ifs if you are very sure that the expression |
45 | // put into ifs if you are very sure that the expression |
| 44 | // is mostly true or mosty false. note that these return |
46 | // is mostly true or mosty false. note that these return |
| 45 | // booleans, not the expression. |
47 | // booleans, not the expression. |
| 46 | #define expect_false(expr) expect ((expr) != 0, 0) |
48 | #define expect_false(expr) expect ((expr) ? 1 : 0, 0) |
| 47 | #define expect_true(expr) expect ((expr) != 0, 1) |
49 | #define expect_true(expr) expect ((expr) ? 1 : 0, 1) |
| 48 | |
50 | |
| 49 | #include <pthread.h> |
51 | #include <pthread.h> |
| 50 | |
52 | |
| 51 | #include <cstddef> |
53 | #include <cstddef> |
| 52 | #include <cmath> |
54 | #include <cmath> |
| … | |
… | |
| 407 | |
409 | |
| 408 | // Xorshift RNGs, George Marsaglia |
410 | // Xorshift RNGs, George Marsaglia |
| 409 | // http://www.jstatsoft.org/v08/i14/paper |
411 | // http://www.jstatsoft.org/v08/i14/paper |
| 410 | // this one is about 40% faster than the tausworthe one above (i.e. not much), |
412 | // this one is about 40% faster than the tausworthe one above (i.e. not much), |
| 411 | // despite the inlining, and has the issue of only creating 2**32-1 numbers. |
413 | // despite the inlining, and has the issue of only creating 2**32-1 numbers. |
|
|
414 | // see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf |
| 412 | struct xorshift_random_generator |
415 | struct xorshift_random_generator |
| 413 | { |
416 | { |
| 414 | uint32_t x, y; |
417 | uint32_t x, y; |
| 415 | |
418 | |
| 416 | void operator =(const xorshift_random_generator &src) |
419 | void operator =(const xorshift_random_generator &src) |
| … | |
… | |
| 540 | |
543 | |
| 541 | struct str_hash |
544 | struct str_hash |
| 542 | { |
545 | { |
| 543 | std::size_t operator ()(const char *s) const |
546 | std::size_t operator ()(const char *s) const |
| 544 | { |
547 | { |
| 545 | unsigned long hash = 0; |
548 | #if 0 |
|
|
549 | uint32_t hash = 0; |
| 546 | |
550 | |
| 547 | /* use the one-at-a-time hash function, which supposedly is |
551 | /* use the one-at-a-time hash function, which supposedly is |
| 548 | * better than the djb2-like one used by perl5.005, but |
552 | * better than the djb2-like one used by perl5.005, but |
| 549 | * certainly is better then the bug used here before. |
553 | * certainly is better then the bug used here before. |
| 550 | * see http://burtleburtle.net/bob/hash/doobs.html |
554 | * see http://burtleburtle.net/bob/hash/doobs.html |
| … | |
… | |
| 557 | } |
561 | } |
| 558 | |
562 | |
| 559 | hash += hash << 3; |
563 | hash += hash << 3; |
| 560 | hash ^= hash >> 11; |
564 | hash ^= hash >> 11; |
| 561 | hash += hash << 15; |
565 | hash += hash << 15; |
|
|
566 | #else |
|
|
567 | // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/) |
|
|
568 | // it is about twice as fast as the one-at-a-time one, |
|
|
569 | // with good distribution. |
|
|
570 | // FNV-1a is faster on many cpus because the multiplication |
|
|
571 | // runs concurrent with the looping logic. |
|
|
572 | uint32_t hash = 2166136261; |
|
|
573 | |
|
|
574 | while (*s) |
|
|
575 | hash = (hash ^ *s++) * 16777619; |
|
|
576 | #endif |
| 562 | |
577 | |
| 563 | return hash; |
578 | return hash; |
| 564 | } |
579 | } |
| 565 | }; |
580 | }; |
| 566 | |
581 | |
| … | |
… | |
| 661 | erase (&obj); |
676 | erase (&obj); |
| 662 | } |
677 | } |
| 663 | }; |
678 | }; |
| 664 | |
679 | |
| 665 | // basically does what strncpy should do, but appends "..." to strings exceeding length |
680 | // basically does what strncpy should do, but appends "..." to strings exceeding length |
|
|
681 | // returns the number of bytes actually used (including \0) |
| 666 | void assign (char *dst, const char *src, int maxlen); |
682 | int assign (char *dst, const char *src, int maxsize); |
| 667 | |
683 | |
| 668 | // type-safe version of assign |
684 | // type-safe version of assign |
| 669 | template<int N> |
685 | template<int N> |
| 670 | inline void assign (char (&dst)[N], const char *src) |
686 | inline int assign (char (&dst)[N], const char *src) |
| 671 | { |
687 | { |
| 672 | assign ((char *)&dst, src, N); |
688 | return assign ((char *)&dst, src, N); |
| 673 | } |
689 | } |
| 674 | |
690 | |
| 675 | typedef double tstamp; |
691 | typedef double tstamp; |
| 676 | |
692 | |
| 677 | // return current time as timestamp |
693 | // return current time as timestamp |
