clang 20.0.0git
lzcntintrin.h
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1/*===---- lzcntintrin.h - LZCNT intrinsics ---------------------------------===
2 *
3 * Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 * See https://llvm.org/LICENSE.txt for license information.
5 * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 *
7 *===-----------------------------------------------------------------------===
8 */
9
10#if !defined __X86INTRIN_H && !defined __IMMINTRIN_H
11#error "Never use <lzcntintrin.h> directly; include <x86intrin.h> instead."
12#endif
13
14#ifndef __LZCNTINTRIN_H
15#define __LZCNTINTRIN_H
16
17/* Define the default attributes for the functions in this file. */
18#define __DEFAULT_FN_ATTRS __attribute__((__always_inline__, __nodebug__, __target__("lzcnt")))
19
20#ifndef _MSC_VER
21/// Counts the number of leading zero bits in the operand.
22///
23/// \headerfile <x86intrin.h>
24///
25/// This intrinsic corresponds to the \c LZCNT instruction.
26///
27/// \param __X
28/// An unsigned 16-bit integer whose leading zeros are to be counted.
29/// \returns An unsigned 16-bit integer containing the number of leading zero
30/// bits in the operand.
31#define __lzcnt16(X) __builtin_ia32_lzcnt_u16((unsigned short)(X))
32#endif // _MSC_VER
33
34/// 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 32-bit integer whose leading zeros are to be counted.
42/// \returns An unsigned 32-bit integer containing the number of leading zero
43/// bits in the operand.
44/// \see _lzcnt_u32
45static __inline__ unsigned int __DEFAULT_FN_ATTRS
46__lzcnt32(unsigned int __X)
47{
48 return __builtin_ia32_lzcnt_u32(__X);
49}
50
51/// Counts the number of leading zero bits in the operand.
52///
53/// \headerfile <x86intrin.h>
54///
55/// This intrinsic corresponds to the \c LZCNT instruction.
56///
57/// \param __X
58/// An unsigned 32-bit integer whose leading zeros are to be counted.
59/// \returns An unsigned 32-bit integer containing the number of leading zero
60/// bits in the operand.
61/// \see __lzcnt32
62static __inline__ unsigned int __DEFAULT_FN_ATTRS
63_lzcnt_u32(unsigned int __X)
64{
65 return __builtin_ia32_lzcnt_u32(__X);
66}
67
68#ifdef __x86_64__
69#ifndef _MSC_VER
70/// Counts the number of leading zero bits in the operand.
71///
72/// \headerfile <x86intrin.h>
73///
74/// This intrinsic corresponds to the \c LZCNT instruction.
75///
76/// \param __X
77/// An unsigned 64-bit integer whose leading zeros are to be counted.
78/// \returns An unsigned 64-bit integer containing the number of leading zero
79/// bits in the operand.
80/// \see _lzcnt_u64
81#define __lzcnt64(X) __builtin_ia32_lzcnt_u64((unsigned long long)(X))
82#endif // _MSC_VER
83
84/// Counts the number of leading zero bits in the operand.
85///
86/// \headerfile <x86intrin.h>
87///
88/// This intrinsic corresponds to the \c LZCNT instruction.
89///
90/// \param __X
91/// An unsigned 64-bit integer whose leading zeros are to be counted.
92/// \returns An unsigned 64-bit integer containing the number of leading zero
93/// bits in the operand.
94/// \see __lzcnt64
95static __inline__ unsigned long long __DEFAULT_FN_ATTRS
96_lzcnt_u64(unsigned long long __X)
97{
98 return __builtin_ia32_lzcnt_u64(__X);
99}
100#endif
101
102#undef __DEFAULT_FN_ATTRS
103
104#endif /* __LZCNTINTRIN_H */
static __inline__ unsigned int __DEFAULT_FN_ATTRS __lzcnt32(unsigned int __X)
Counts the number of leading zero bits in the operand.
Definition: lzcntintrin.h:46
static __inline__ unsigned int __DEFAULT_FN_ATTRS _lzcnt_u32(unsigned int __X)
Counts the number of leading zero bits in the operand.
Definition: lzcntintrin.h:63
#define __DEFAULT_FN_ATTRS
Definition: lzcntintrin.h:18