1/*===---- lzcntintrin.h - LZCNT intrinsics ---------------------------------=== 2 * 3 * Permission is hereby granted, free of charge, to any person obtaining a copy 4 * of this software and associated documentation files (the "Software"), to deal 5 * in the Software without restriction, including without limitation the rights 6 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 7 * copies of the Software, and to permit persons to whom the Software is 8 * furnished to do so, subject to the following conditions: 9 * 10 * The above copyright notice and this permission notice shall be included in 11 * all copies or substantial portions of the Software. 12 * 13 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 14 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 15 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 16 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 17 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 18 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 19 * THE SOFTWARE. 20 * 21 *===-----------------------------------------------------------------------=== 22 */ 23 24#if !defined __X86INTRIN_H && !defined __IMMINTRIN_H 25#error "Never use <lzcntintrin.h> directly; include <x86intrin.h> instead." 26#endif 27 28#ifndef __LZCNTINTRIN_H 29#define __LZCNTINTRIN_H 30 31/* Define the default attributes for the functions in this file. */ 32#define __DEFAULT_FN_ATTRS __attribute__((__always_inline__, __nodebug__, __target__("lzcnt"))) 33 34/// \brief Counts the number of leading zero bits in the operand. 35/// 36/// \headerfile <x86intrin.h> 37/// 38/// This intrinsic corresponds to the \c LZCNT instruction. 39/// 40/// \param __X 41/// An unsigned 16-bit integer whose leading zeros are to be counted. 42/// \returns An unsigned 16-bit integer containing the number of leading zero 43/// bits in the operand. 44static __inline__ unsigned short __DEFAULT_FN_ATTRS 45__lzcnt16(unsigned short __X) 46{ 47 return __X ? __builtin_clzs(__X) : 16; 48} 49 50/// \brief Counts the number of leading zero bits in the operand. 51/// 52/// \headerfile <x86intrin.h> 53/// 54/// This intrinsic corresponds to the \c LZCNT instruction. 55/// 56/// \param __X 57/// An unsigned 32-bit integer whose leading zeros are to be counted. 58/// \returns An unsigned 32-bit integer containing the number of leading zero 59/// bits in the operand. 60static __inline__ unsigned int __DEFAULT_FN_ATTRS 61__lzcnt32(unsigned int __X) 62{ 63 return __X ? __builtin_clz(__X) : 32; 64} 65 66/// \brief Counts the number of leading zero bits in the operand. 67/// 68/// \headerfile <x86intrin.h> 69/// 70/// This intrinsic corresponds to the \c LZCNT instruction. 71/// 72/// \param __X 73/// An unsigned 32-bit integer whose leading zeros are to be counted. 74/// \returns An unsigned 32-bit integer containing the number of leading zero 75/// bits in the operand. 76static __inline__ unsigned int __DEFAULT_FN_ATTRS 77_lzcnt_u32(unsigned int __X) 78{ 79 return __X ? __builtin_clz(__X) : 32; 80} 81 82#ifdef __x86_64__ 83/// \brief Counts the number of leading zero bits in the operand. 84/// 85/// \headerfile <x86intrin.h> 86/// 87/// This intrinsic corresponds to the \c LZCNT instruction. 88/// 89/// \param __X 90/// An unsigned 64-bit integer whose leading zeros are to be counted. 91/// \returns An unsigned 64-bit integer containing the number of leading zero 92/// bits in the operand. 93static __inline__ unsigned long long __DEFAULT_FN_ATTRS 94__lzcnt64(unsigned long long __X) 95{ 96 return __X ? __builtin_clzll(__X) : 64; 97} 98 99/// \brief Counts the number of leading zero bits in the operand. 100/// 101/// \headerfile <x86intrin.h> 102/// 103/// This intrinsic corresponds to the \c LZCNT instruction. 104/// 105/// \param __X 106/// An unsigned 64-bit integer whose leading zeros are to be counted. 107/// \returns An unsigned 64-bit integer containing the number of leading zero 108/// bits in the operand. 109static __inline__ unsigned long long __DEFAULT_FN_ATTRS 110_lzcnt_u64(unsigned long long __X) 111{ 112 return __X ? __builtin_clzll(__X) : 64; 113} 114#endif 115 116#undef __DEFAULT_FN_ATTRS 117 118#endif /* __LZCNTINTRIN_H */ 119