clang/lib/Headers/lzcntintrin.h

   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
  45 static __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
  62 static __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
  95 static __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 */