diff options
Diffstat (limited to 'sc4pd/headers/plugin_interface/clz.h')
| -rw-r--r-- | sc4pd/headers/plugin_interface/clz.h | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/sc4pd/headers/plugin_interface/clz.h b/sc4pd/headers/plugin_interface/clz.h new file mode 100644 index 0000000..f205c02 --- /dev/null +++ b/sc4pd/headers/plugin_interface/clz.h @@ -0,0 +1,195 @@ +/* + SuperCollider real time audio synthesis system + Copyright (c) 2002 James McCartney. All rights reserved. + http://www.audiosynth.com + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +*/ +/* + +count leading zeroes function and those that can be derived from it + +*/ + + +#ifndef _CLZ_ +#define _CLZ_ + +#include "SC_Types.h" + +#ifdef __MWERKS__ + +#define __PPC__ 1 +#define __X86__ 0 + +// powerpc native count leading zeroes instruction: +#define CLZ(x) ((int)__cntlzw((unsigned int)x)) + +#elif defined(SC_WIN32) && !defined(__GCC__) + +static int32 CLZ( int32 arg ) +{ + __asm{ + bsr eax, arg + jnz non_zero + mov arg, 32 + jmp end +non_zero: + xor eax, 31 + mov arg, eax +end: + } + return arg; +} + +#elif defined(__ppc__) || defined(__powerpc__) || defined(__PPC__) + +static __inline__ int32 CLZ(int32 arg) { + __asm__ volatile("cntlzw %0, %1" : "=r" (arg) : "r" (arg)); + return arg; +} + +#elif defined(__i386__) || defined(__x86_64__) +static __inline__ int32 CLZ(int32 arg) { + if (arg) { + __asm__ volatile("bsrl %0, %0\nxorl $31, %0\n" + : "=r" (arg) : "0" (arg)); + } else { + arg = 32; + } + return arg; +} + +#else +# error "clz.h: Unsupported architecture" +#endif + +// count trailing zeroes +inline int32 CTZ(int32 x) +{ + return 32 - CLZ(~x & (x-1)); +} + +// count leading ones +inline int32 CLO(int32 x) +{ + return CLZ(~x); +} + +// count trailing ones +inline int32 CTO(int32 x) +{ + return 32 - CLZ(x & (~x-1)); +} + +// number of bits required to represent x. +inline int32 NUMBITS(int32 x) +{ + return 32 - CLZ(x); +} + +// log2 of the next power of two greater than or equal to x. +inline int32 LOG2CEIL(int32 x) +{ + return 32 - CLZ(x - 1); +} + +// next power of two greater than or equal to x +inline int32 NEXTPOWEROFTWO(int32 x) +{ + return 1L << LOG2CEIL(x); +} + +// is x a power of two +inline bool ISPOWEROFTWO(int32 x) +{ + return (x & (x-1)) == 0; +} + +// input a series of counting integers, outputs a series of gray codes . +inline int32 GRAYCODE(int32 x) +{ + return x & (x>>1); +} + +// find least significant bit +inline int32 LSBit(int32 x) +{ + return x & -x; +} + +// find least significant bit position +inline int32 LSBitPos(int32 x) +{ + return CTZ(x & -x); +} + +// find most significant bit position +inline int32 MSBitPos(int32 x) +{ + return 31 - CLZ(x); +} + +// find most significant bit +inline int32 MSBit(int32 x) +{ + return 1L << MSBitPos(x); +} + +// count number of one bits +inline uint32 ONES(uint32 x) +{ + uint32 t; + x = x - ((x >> 1) & 0x55555555); + t = ((x >> 2) & 0x33333333); + x = (x & 0x33333333) + t; + x = (x + (x >> 4)) & 0x0F0F0F0F; + x = x + (x << 8); + x = x + (x << 16); + return x >> 24; +} + +// count number of zero bits +inline uint32 ZEROES(uint32 x) +{ + return ONES(~x); +} + + +// reverse bits in a word +inline uint32 BitReverse(uint32 x) +{ + x = ((x & 0xAAAAAAAA) >> 1) | ((x & 0x55555555) << 1); + x = ((x & 0xCCCCCCCC) >> 2) | ((x & 0x33333333) << 2); + x = ((x & 0xF0F0F0F0) >> 4) | ((x & 0x0F0F0F0F) << 4); + x = ((x & 0xFF00FF00) >> 8) | ((x & 0x00FF00FF) << 8); + return (x >> 16) | (x << 16); +} + +// barrel shifts +inline uint32 RotateRight (uint32 x, uint32 s) +{ + s = s & 31; + return (x << (32-s)) | (x >> s); +} + +inline uint32 RotateLeft (uint32 x, uint32 s) +{ + s = s & 31; + return (x >> (32-s)) | (x << s); +} + +#endif + |