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Comparing deliantra/server/include/util.h (file contents):
Revision 1.94 by root, Sun Nov 8 16:13:45 2009 UTC vs.
Revision 1.100 by root, Thu Apr 22 13:01:58 2010 UTC

1/* 1/*
2 * This file is part of Deliantra, the Roguelike Realtime MMORPG. 2 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
3 * 3 *
4 * Copyright (©) 2005,2006,2007,2008 Marc Alexander Lehmann / Robin Redeker / the Deliantra team 4 * Copyright (©) 2005,2006,2007,2008,2009,2010 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5 * 5 *
6 * Deliantra is free software: you can redistribute it and/or modify it under 6 * Deliantra is free software: you can redistribute it and/or modify it under
7 * the terms of the Affero GNU General Public License as published by the 7 * the terms of the Affero GNU General Public License as published by the
8 * Free Software Foundation, either version 3 of the License, or (at your 8 * Free Software Foundation, either version 3 of the License, or (at your
9 * option) any later version. 9 * option) any later version.
… …
99 99
100// sign0 returns -1, 0 or +1 100// sign0 returns -1, 0 or +1
101template<typename T> 101template<typename T>
102static inline T sign0 (T v) { return v ? sign (v) : 0; } 102static inline T sign0 (T v) { return v ? sign (v) : 0; }
103 103
104template<typename T, typename U>
105static inline T copysign (T a, U b) { return a > 0 ? b : -b; }
106
104// div* only work correctly for div > 0 107// div* only work correctly for div > 0
105// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 108// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
106template<typename T> static inline T div (T val, T div) 109template<typename T> static inline T div (T val, T div)
107{ 110{
108 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div; 111 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div;
… …
240absdir (int d) 243absdir (int d)
241{ 244{
242 return ((d - 1) & 7) + 1; 245 return ((d - 1) & 7) + 1;
243} 246}
244 247
248// avoid ctz name because netbsd or freebsd spams it's namespace with it
249#if GCC_VERSION(3,4)
250static inline int least_significant_bit (uint32_t x)
251{
252 return __builtin_ctz (x);
253}
254#else
255int least_significant_bit (uint32_t x);
256#endif
257
258#define for_all_bits_sparse_32(mask, idxvar) \
259 for (uint32_t idxvar, mask_ = mask; \
260 mask_ && ((idxvar = least_significant_bit (mask_)), mask_ &= ~(1 << idxvar), 1);)
261
245extern ssize_t slice_alloc; // statistics 262extern ssize_t slice_alloc; // statistics
246 263
247void *salloc_ (int n) throw (std::bad_alloc); 264void *salloc_ (int n) throw (std::bad_alloc);
248void *salloc_ (int n, void *src) throw (std::bad_alloc); 265void *salloc_ (int n, void *src) throw (std::bad_alloc);
249 266
… …
453 return !is_constant (num) ? get_range (num) // non-constant 470 return !is_constant (num) ? get_range (num) // non-constant
454 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two 471 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
455 : this->next () & (num - 1); // constant, power-of-two 472 : this->next () & (num - 1); // constant, power-of-two
456 } 473 }
457 474
458 // return a number within (min .. max) 475 // return a number within the closed interval [min .. max]
459 int operator () (int r_min, int r_max) 476 int operator () (int r_min, int r_max)
460 { 477 {
461 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max 478 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
462 ? r_min + operator ()(r_max - r_min + 1) 479 ? r_min + operator ()(r_max - r_min + 1)
463 : get_range (r_min, r_max); 480 : get_range (r_min, r_max);
464 } 481 }
465 482
483 // return a number within the closed interval [0..1]
466 double operator ()() 484 double operator ()()
467 { 485 {
468 return this->next () / (double)0xFFFFFFFFU; 486 return this->next () / (double)0xFFFFFFFFU;
469 } 487 }
470 488
… …
546typedef refptr<object> object_ptr; 564typedef refptr<object> object_ptr;
547typedef refptr<archetype> arch_ptr; 565typedef refptr<archetype> arch_ptr;
548typedef refptr<client> client_ptr; 566typedef refptr<client> client_ptr;
549typedef refptr<player> player_ptr; 567typedef refptr<player> player_ptr;
550 568
569#define STRHSH_NULL 2166136261
570
571static inline uint32_t
572strhsh (const char *s)
573{
574 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
575 // it is about twice as fast as the one-at-a-time one,
576 // with good distribution.
577 // FNV-1a is faster on many cpus because the multiplication
578 // runs concurrently with the looping logic.
579 uint32_t hash = STRHSH_NULL;
580
581 while (*s)
582 hash = (hash ^ *s++) * 16777619U;
583
584 return hash;
585}
586
587static inline uint32_t
588memhsh (const char *s, size_t len)
589{
590 uint32_t hash = STRHSH_NULL;
591
592 while (len--)
593 hash = (hash ^ *s++) * 16777619U;
594
595 return hash;
596}
597
551struct str_hash 598struct str_hash
552{ 599{
553 std::size_t operator ()(const char *s) const 600 std::size_t operator ()(const char *s) const
554 { 601 {
555#if 0
556 uint32_t hash = 0;
557
558 /* use the one-at-a-time hash function, which supposedly is
559 * better than the djb2-like one used by perl5.005, but
560 * certainly is better then the bug used here before.
561 * see http://burtleburtle.net/bob/hash/doobs.html
562 */
563 while (*s)
564 {
565 hash += *s++;
566 hash += hash << 10;
567 hash ^= hash >> 6;
568 }
569
570 hash += hash << 3;
571 hash ^= hash >> 11;
572 hash += hash << 15;
573#else
574 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
575 // it is about twice as fast as the one-at-a-time one,
576 // with good distribution.
577 // FNV-1a is faster on many cpus because the multiplication
578 // runs concurrent with the looping logic.
579 uint32_t hash = 2166136261;
580
581 while (*s)
582 hash = (hash ^ *s++) * 16777619;
583#endif
584
585 return hash; 602 return strhsh (s);
603 }
604
605 std::size_t operator ()(const shstr &s) const
606 {
607 return strhsh (s);
586 } 608 }
587}; 609};
588 610
589struct str_equal 611struct str_equal
590{ 612{

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