pike.git/src/stuff.c:c7241b7151e11d70cd672a4ee31de06057a50907

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 /*\ ||| This file a part of Pike, and is copyright by Fredrik Hubinette ||| Pike is distributed as GPL (General Public License) ||| See the files COPYING and DISCLAIMER for more information. \*/ /* * $Id: stuff.c,v 1.12 2000/08/10 09:20:00 grubba Exp $ */ #include "global.h" #include "stuff.h" #include "stralloc.h" /* Not all of these are primes, but they should be adequate */ PMOD_EXPORT INT32 hashprimes[32] = { 31, /* ~ 2^0 = 1 */ 31, /* ~ 2^1 = 2 */ 31, /* ~ 2^2 = 4 */ 31, /* ~ 2^3 = 8 */ 31, /* ~ 2^4 = 16 */ 31, /* ~ 2^5 = 32 */ 61, /* ~ 2^6 = 64 */ 127, /* ~ 2^7 = 128 */ 251, /* ~ 2^8 = 256 */ 541, /* ~ 2^9 = 512 */ 1151, /* ~ 2^10 = 1024 */ 2111, /* ~ 2^11 = 2048 */ 4327, /* ~ 2^12 = 4096 */ 8803, /* ~ 2^13 = 8192 */ 17903, /* ~ 2^14 = 16384 */ 32321, /* ~ 2^15 = 32768 */ 65599, /* ~ 2^16 = 65536 */ 133153, /* ~ 2^17 = 131072 */ 270001, /* ~ 2^18 = 264144 */ 547453, /* ~ 2^19 = 524288 */ 1109891, /* ~ 2^20 = 1048576 */ 2000143, /* ~ 2^21 = 2097152 */ 4561877, /* ~ 2^22 = 4194304 */ 9248339, /* ~ 2^23 = 8388608 */ 16777215, /* ~ 2^24 = 16777216 */ 33554431, /* ~ 2^25 = 33554432 */ 67108863, /* ~ 2^26 = 67108864 */ 134217727, /* ~ 2^27 = 134217728 */ 268435455, /* ~ 2^28 = 268435456 */ 536870911, /* ~ 2^29 = 536870912 */ 1073741823,/* ~ 2^30 = 1073741824 */ 2147483647,/* ~ 2^31 = 2147483648 */ }; /* same thing as (int)floor(log((double)x) / log(2.0)) */ /* Except a bit quicker :) (hopefully) */ PMOD_EXPORT int my_log2(size_t x) { static signed char bit[256] = { -1, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, }; register size_t tmp; #if SIZEOF_CHAR_P > 4 if((tmp=(x>>32))) { if((x=(tmp>>16))) { if((tmp=(x>>8))) return bit[tmp]+56; return bit[x]+48; } if((x=(tmp>>8))) return bit[x]+40; return bit[tmp]+32; } #endif /* SIZEOF_CHAP_P > 4 */ if((tmp=(x>>16))) { if((x=(tmp>>8))) return bit[x]+24; return bit[tmp]+16; } if((tmp=(x>>8))) return bit[tmp]+8; return bit[x]; } /* Return the number of bits in a 32-bit integer */ PMOD_EXPORT int count_bits(unsigned INT32 x) { #define B(X) X+0,X+1,X+1,X+2,\ X+1,X+2,X+2,X+3,\ X+1,X+2,X+2,X+3,\ X+2,X+3,X+3,X+4 static char bits[256] = { B(0), B(1), B(1), B(2), B(1), B(2), B(2), B(3), B(1), B(2), B(2), B(3), B(2), B(3), B(3), B(4) }; return (bits[x & 255] + bits[(x>>8) & 255] + bits[(x>>16) & 255] + bits[(x>>24) & 255]); } /* Return true for integers with more than one bit set */ PMOD_EXPORT int is_more_than_one_bit(unsigned INT32 x) { return !!(x & (x-1)); } PMOD_EXPORT double my_strtod(char *nptr, char **endptr) { double tmp=STRTOD(nptr,endptr); if(*endptr>nptr) { if(endptr[0][-1]=='.') endptr[0]--; } return tmp; }

pike.git/ src/ stuff.c > c7241b7151e11d70cd672a4ee31de06057a50907 [Annotate]