// -*- Mode: C -*- // // Cforall Version 1.0.0 Copyright (C) 2020 University of Waterloo // // The contents of this file are covered under the licence agreement in the // file "LICENCE" distributed with Cforall. // // bitmanip.hfa -- // // Author : Peter A. Buhr // Created On : Sat Mar 14 18:12:27 2020 // Last Modified By : Peter A. Buhr // Last Modified On : Tue Jun 9 15:14:04 2020 // Update Count : 123 // #pragma once // Reference: Bit Twiddling Hacks: http://graphics.stanford.edu/%7Eseander/bithacks.html#CountBitsSetNaive // Bits are numbered 1-N. //#include #define __bitsizeof( n ) (sizeof(n) * __CHAR_BIT__) static inline { // Count leading 0 bits. unsigned int leading0s( unsigned char n ) { return n != 0 ? __builtin_clz( n ) - (__bitsizeof(unsigned int) - __bitsizeof(n)) : __bitsizeof(n); } unsigned int leading0s( unsigned short int n ) { return n != 0 ? __builtin_clz( n ) - (__bitsizeof(unsigned int) - __bitsizeof(n)) : __bitsizeof(n); } unsigned int leading0s( unsigned int n ) { return n != 0 ? __builtin_clz( n ) : __bitsizeof(n); } unsigned int leading0s( unsigned long int n ) { return n != 0 ? __builtin_clzl( n ) : __bitsizeof(n); } unsigned int leading0s( unsigned long long int n ) { return n != 0 ? __builtin_clzll( n ) : __bitsizeof(n); } // Count trailing 0 bits. unsigned int trailing0s( unsigned char n ) { return n != 0 ? __builtin_ctz( n ) : __bitsizeof(n); } unsigned int trailing0s( unsigned short int n ) { return n != 0 ? __builtin_ctz( n ) : __bitsizeof(n); } unsigned int trailing0s( unsigned int n ) { return n != 0 ? __builtin_ctz( n ) : __bitsizeof(n); } unsigned int trailing0s( unsigned long int n ) { return n != 0 ? __builtin_ctzl( n ) : __bitsizeof(n); } unsigned int trailing0s( unsigned long long int n ) { return n != 0 ? __builtin_ctzll( n ) : __bitsizeof(n); } // Count all 1 bits. unsigned int all1s( unsigned char n ) { return __builtin_popcount( n ); } unsigned int all1s( unsigned short int n ) { return __builtin_popcount( n ); } unsigned int all1s( unsigned int n ) { return __builtin_popcount( n ); } unsigned int all1s( unsigned long int n ) { return __builtin_popcountl( n ); } unsigned int all1s( unsigned long long int n ) { return __builtin_popcountll( n ); } // Count all 0 bits. unsigned int all0s( unsigned char n ) { return __builtin_popcount( (typeof(n))~n ); } unsigned int all0s( unsigned short int n ) { return __builtin_popcount( (typeof(n))~n ); } unsigned int all0s( unsigned int n ) { return __builtin_popcount( ~n ); } unsigned int all0s( unsigned long int n ) { return __builtin_popcountl( ~n ); } unsigned int all0s( unsigned long long int n ) { return __builtin_popcountll( ~n ); } // Find least significiant zero bit. (ffs) unsigned int low0( unsigned char n ) { return __builtin_ffs( (typeof(n))~n ); } unsigned int low0( unsigned short int n ) { return __builtin_ffs( (typeof(n))~n ); } unsigned int low0( unsigned int n ) { return __builtin_ffs( ~n ); } unsigned int low0( unsigned long int n ) { return __builtin_ffsl( ~n ); } unsigned int low0( unsigned long long int n ) { return __builtin_ffsll( ~n ); } // Find least significiant one bit. unsigned int low1( unsigned int n ) { return __builtin_ffs( n ); } unsigned int low1( unsigned long int n ) { return __builtin_ffsl( n ); } unsigned int low1( unsigned long long int n ) { return __builtin_ffsll( n ); } // Find most significiant zero bit. unsigned int high0( unsigned char n ) { return n == (typeof(n))-1 ? 0 : __bitsizeof(unsigned int) - __builtin_clz( (typeof(n))~n ); } unsigned int high0( unsigned short int n ) { return n == (typeof(n))-1 ? 0 : __bitsizeof(unsigned int) - __builtin_clz( (typeof(n))~n ); } unsigned int high0( unsigned int n ) { return n == -1 ? 0 : __bitsizeof(n) - __builtin_clz( ~n ); } unsigned int high0( unsigned long int n ) { return n == -1 ? 0 : __bitsizeof(n) - __builtin_clzl( ~n ); } unsigned int high0( unsigned long long int n ) { return n == -1 ? 0 : __bitsizeof(n) - __builtin_clzll( ~n ); } // Find most significiant one bit. unsigned int high1( unsigned char n ) { return n == 0 ? 0 : __bitsizeof(unsigned int) - __builtin_clz( n ); } unsigned int high1( unsigned short int n ) { return n == 0 ? 0 : __bitsizeof(unsigned int) - __builtin_clz( n ); } unsigned int high1( unsigned int n ) { return n == 0 ? 0 : __bitsizeof(n) - __builtin_clz( n ); } unsigned int high1( unsigned long int n ) { return n == 0 ? 0 : __bitsizeof(n) - __builtin_clzl( n ); } unsigned int high1( unsigned long long int n ) { return n == 0 ? 0 : __bitsizeof(n) - __builtin_clzll( n ); } // Check for power of 2, clears bits below n, rounding down to the next lower multiple of n. 0 is not a power of 2 // but this computation returns true because of the two's complement, so it is a special case. bool is_pow2( unsigned char n ) { return n == 0 ? false : (n & (n - 1)) == 0; } bool is_pow2( unsigned short int n ) { return n == 0 ? false : (n & (n - 1)) == 0; } bool is_pow2( unsigned int n ) { return n == 0 ? false : (n & (n - 1)) == 0; } bool is_pow2( unsigned long int n ) { return n == 0 ? false : (n & (n - 1)) == 0; } bool is_pow2( unsigned long long int n ) { return n == 0 ? false : (n & (n - 1)) == 0; } // Returns n aligned at the floor of align, clear bits above or equal to align, giving n % align. signed char floor2( signed char n, char align ) { /*assert( is_pow2( align ) );*/ return n & -align; } unsigned char floor2( unsigned char n, unsigned char align ) { /*assert( is_pow2( align ) );*/ return n & -align; } short int floor2( short int n, short int align ) { /*assert( is_pow2( align ) );*/ return n & -align; } unsigned short int floor2( unsigned short int n, unsigned short int align ) { /*assert( is_pow2( align ) );*/ return n & -align; } int floor2( int n, int align ) { /*assert( is_pow2( align ) );*/ return n & -align; } unsigned int floor2( unsigned int n, unsigned int align ) { /*assert( is_pow2( align ) );*/ return n & -align; } long int floor2( long int n, long int align ) { /*assert( is_pow2( align ) );*/ return n & -align; } unsigned long int floor2( unsigned long int n, unsigned long int align ) { /*assert( is_pow2( align ) );*/ return n & -align; } long long int floor2( long long int n, long long int align ) { /*assert( is_pow2( align ) );*/ return n & -align; } unsigned long long int floor2( unsigned long long int n, unsigned long long int align ) { /*assert( is_pow2( align ) );*/ return n & -align; } // forall( otype T | { T ?&?( T, T ); T -?( T ); } ) // T floor2( T n, T align ) { /* assert( is_pow2( align ) ); */ return n & -align; } signed char floor( signed char n, char align ) { return n / align * align; } unsigned char floor( unsigned char n, unsigned char align ) { return n / align * align; } short int floor( short int n, short int align ) { return n / align * align; } unsigned short int floor( unsigned short int n, unsigned short int align ) { return n / align * align; } int floor( int n, int align ) { return n / align * align; } unsigned int floor( unsigned int n, unsigned int align ) { return n / align * align; } long int floor( long int n, long int align ) { return n / align * align; } unsigned long int floor( unsigned long int n, unsigned long int align ) { return n / align * align; } long long int floor( long long int n, long long int align ) { return n / align * align; } unsigned long long int floor( unsigned long long int n, unsigned long long int align ) { return n / align * align; } // forall( otype T | { T ?/?( T, T ); T ?*?( T, T ); } ) // T floor( T n, T align ) { return n / align * align; } // Returns n aligned at the ceiling of align, negate, round down, negate is the same as round up. signed char ceiling2( signed char n, char align ) { /*assert( is_pow2( align ) );*/ return -floor2( -n, align ); } unsigned char ceiling2( unsigned char n, unsigned char align ) { /*assert( is_pow2( align ) );*/ return -floor2( -n, align ); } short int ceiling2( short int n, short int align ) { /*assert( is_pow2( align ) );*/ return -floor2( -n, align ); } unsigned short int ceiling2( unsigned short int n, unsigned short int align ) { /*assert( is_pow2( align ) );*/ return -floor2( -n, align ); } int ceiling2( int n, int align ) { /*assert( is_pow2( align ) );*/ return -floor2( -n, align ); } unsigned int ceiling2( unsigned int n, unsigned int align ) { /*assert( is_pow2( align ) );*/ return -floor2( -n, align ); } long int ceiling2( long int n, long int align ) { /*assert( is_pow2( align ) );*/ return -floor2( -n, align ); } unsigned long int ceiling2( unsigned long int n, unsigned long int align ) { /*assert( is_pow2( align ) );*/ return -floor2( -n, align ); } long long int ceiling2( long long int n, long long int align ) { /*assert( is_pow2( align ) );*/ return -floor2( -n, align ); } unsigned long long int ceiling2( unsigned long long int n, unsigned long long int align ) { /*assert( is_pow2( align ) );*/ return -floor2( -n, align ); } // forall( otype T | { T floor2( T, T ); T -?( T ); } ) // T ceiling2( T n, T align ) { /* assert( is_pow2( align ) ); */ return -floor2( -n, align ); } signed char ceiling( signed char n, char align ) { return (n + (align - 1)) / align; } unsigned char ceiling( unsigned char n, unsigned char align ) { return (n + (align - 1)) / align; } short int ceiling( short int n, short int align ) { return (n + (align - 1)) / align; } unsigned short int ceiling( unsigned short int n, unsigned short int align ) { return (n + (align - 1)) / align; } int ceiling( int n, int align ) { return (n + (align - 1)) / align; } unsigned int ceiling( unsigned int n, unsigned int align ) { return (n + (align - 1)) / align; } long int ceiling( long int n, long int align ) { return (n + (align - 1)) / align; } unsigned long int ceiling( unsigned long int n, unsigned long int align ) { return (n + (align - 1)) / align; } long long int ceiling( long long int n, long long int align ) { return (n + (align - 1)) / align; } unsigned long long int ceiling( unsigned long long int n, unsigned long long int align ) { return (n + (align - 1)) / align; } // forall( otype T | { void ?{}( T &, one_t ); T ?+?( T, T ); T ?-?( T, T ); T ?/?( T, T ); } ) // T ceiling( T n, T align ) { return (n + (align - (T){1})) / align; } } // distribution // Local Variables: // // tab-width: 4 // // End: //