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Diffstat (limited to 'libs/appleutility/CoreAudio/PublicUtility/CABitOperations.h')
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diff --git a/libs/appleutility/CoreAudio/PublicUtility/CABitOperations.h b/libs/appleutility/CoreAudio/PublicUtility/CABitOperations.h new file mode 100644 index 0000000000..21cb516a60 --- /dev/null +++ b/libs/appleutility/CoreAudio/PublicUtility/CABitOperations.h @@ -0,0 +1,206 @@ +/* + File: CABitOperations.h + Abstract: Part of CoreAudio Utility Classes + Version: 1.1 + + Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple + Inc. ("Apple") in consideration of your agreement to the following + terms, and your use, installation, modification or redistribution of + this Apple software constitutes acceptance of these terms. If you do + not agree with these terms, please do not use, install, modify or + redistribute this Apple software. + + In consideration of your agreement to abide by the following terms, and + subject to these terms, Apple grants you a personal, non-exclusive + license, under Apple's copyrights in this original Apple software (the + "Apple Software"), to use, reproduce, modify and redistribute the Apple + Software, with or without modifications, in source and/or binary forms; + provided that if you redistribute the Apple Software in its entirety and + without modifications, you must retain this notice and the following + text and disclaimers in all such redistributions of the Apple Software. + Neither the name, trademarks, service marks or logos of Apple Inc. may + be used to endorse or promote products derived from the Apple Software + without specific prior written permission from Apple. Except as + expressly stated in this notice, no other rights or licenses, express or + implied, are granted by Apple herein, including but not limited to any + patent rights that may be infringed by your derivative works or by other + works in which the Apple Software may be incorporated. + + The Apple Software is provided by Apple on an "AS IS" basis. APPLE + MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION + THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS + FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND + OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS. + + IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL + OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + INTERRUPTION) ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, + MODIFICATION AND/OR DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED + AND WHETHER UNDER THEORY OF CONTRACT, TORT (INCLUDING NEGLIGENCE), + STRICT LIABILITY OR OTHERWISE, EVEN IF APPLE HAS BEEN ADVISED OF THE + POSSIBILITY OF SUCH DAMAGE. + + Copyright (C) 2014 Apple Inc. All Rights Reserved. + +*/ +#ifndef _CABitOperations_h_ +#define _CABitOperations_h_ + +#if !defined(__COREAUDIO_USE_FLAT_INCLUDES__) + //#include <CoreServices/../Frameworks/CarbonCore.framework/Headers/MacTypes.h> + #include <CoreFoundation/CFBase.h> +#else +// #include <MacTypes.h> + #include "CFBase.h" +#endif +#include <TargetConditionals.h> + +// return whether a number is a power of two +inline UInt32 IsPowerOfTwo(UInt32 x) +{ + return (x & (x-1)) == 0; +} + +// count the leading zeros in a word +// Metrowerks Codewarrior. powerpc native count leading zeros instruction: +// I think it's safe to remove this ... +//#define CountLeadingZeroes(x) ((int)__cntlzw((unsigned int)x)) + +inline UInt32 CountLeadingZeroes(UInt32 arg) +{ +// GNUC / LLVM have a builtin +#if defined(__GNUC__) || defined(__llvm___) +#if (TARGET_CPU_X86 || TARGET_CPU_X86_64) + if (arg == 0) return 32; +#endif // TARGET_CPU_X86 || TARGET_CPU_X86_64 + return __builtin_clz(arg); +#elif TARGET_OS_WIN32 + UInt32 tmp; + __asm{ + bsr eax, arg + mov ecx, 63 + cmovz eax, ecx + xor eax, 31 + mov tmp, eax // this moves the result in tmp to return. + } + return tmp; +#else +#error "Unsupported architecture" +#endif // defined(__GNUC__) +} +// Alias (with different spelling) +#define CountLeadingZeros CountLeadingZeroes + +inline UInt32 CountLeadingZeroesLong(UInt64 arg) +{ +// GNUC / LLVM have a builtin +#if defined(__GNUC__) || defined(__llvm___) +#if (TARGET_CPU_X86 || TARGET_CPU_X86_64) + if (arg == 0) return 64; +#endif // TARGET_CPU_X86 || TARGET_CPU_X86_64 + return __builtin_clzll(arg); +#elif TARGET_OS_WIN32 + UInt32 x = CountLeadingZeroes((UInt32)(arg >> 32)); + if(x < 32) + return x; + else + return 32+CountLeadingZeroes((UInt32)arg); +#else +#error "Unsupported architecture" +#endif // defined(__GNUC__) +} +#define CountLeadingZerosLong CountLeadingZeroesLong + +// count trailing zeroes +inline UInt32 CountTrailingZeroes(UInt32 x) +{ + return 32 - CountLeadingZeroes(~x & (x-1)); +} + +// count leading ones +inline UInt32 CountLeadingOnes(UInt32 x) +{ + return CountLeadingZeroes(~x); +} + +// count trailing ones +inline UInt32 CountTrailingOnes(UInt32 x) +{ + return 32 - CountLeadingZeroes(x & (~x-1)); +} + +// number of bits required to represent x. +inline UInt32 NumBits(UInt32 x) +{ + return 32 - CountLeadingZeroes(x); +} + +// base 2 log of next power of two greater or equal to x +inline UInt32 Log2Ceil(UInt32 x) +{ + return 32 - CountLeadingZeroes(x - 1); +} + +// base 2 log of next power of two less or equal to x +inline UInt32 Log2Floor(UInt32 x) +{ + return 32 - CountLeadingZeroes(x) - 1; +} + +// next power of two greater or equal to x +inline UInt32 NextPowerOfTwo(UInt32 x) +{ + return 1 << Log2Ceil(x); +} + +// counting the one bits in a word +inline UInt32 CountOnes(UInt32 x) +{ + // secret magic algorithm for counting bits in a word. + x = x - ((x >> 1) & 0x55555555); + x = (x & 0x33333333) + ((x >> 2) & 0x33333333); + return (((x + (x >> 4)) & 0x0F0F0F0F) * 0x01010101) >> 24; +} + +// counting the zero bits in a word +inline UInt32 CountZeroes(UInt32 x) +{ + return CountOnes(~x); +} + +// return the bit position (0..31) of the least significant bit +inline UInt32 LSBitPos(UInt32 x) +{ + return CountTrailingZeroes(x & -(SInt32)x); +} + +// isolate the least significant bit +inline UInt32 LSBit(UInt32 x) +{ + return x & -(SInt32)x; +} + +// return the bit position (0..31) of the most significant bit +inline UInt32 MSBitPos(UInt32 x) +{ + return 31 - CountLeadingZeroes(x); +} + +// isolate the most significant bit +inline UInt32 MSBit(UInt32 x) +{ + return 1 << MSBitPos(x); +} + +// Division optimized for power of 2 denominators +inline UInt32 DivInt(UInt32 numerator, UInt32 denominator) +{ + if(IsPowerOfTwo(denominator)) + return numerator >> (31 - CountLeadingZeroes(denominator)); + else + return numerator/denominator; +} + +#endif + |