arch/x86/include/asm/arch_hweight.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_X86_HWEIGHT_H
   3 #define _ASM_X86_HWEIGHT_H
   4
   5 #include <asm/cpufeatures.h>
   6
   7 #ifdef CONFIG_64BIT
   8 #define REG_IN "D"
   9 #define REG_OUT "a"
  10 #else
  11 #define REG_IN "a"
  12 #define REG_OUT "a"
  13 #endif
  14
  15 static __always_inline unsigned int __arch_hweight32(unsigned int w)
  16 {
  17         unsigned int res;
  18
  19         asm (ALTERNATIVE("call __sw_hweight32", "popcntl %1, %0", X86_FEATURE_POPCNT)
  20                          : "="REG_OUT (res)
  21                          : REG_IN (w));
  22
  23         return res;
  24 }
  25
  26 static inline unsigned int __arch_hweight16(unsigned int w)
  27 {
  28         return __arch_hweight32(w & 0xffff);
  29 }
  30
  31 static inline unsigned int __arch_hweight8(unsigned int w)
  32 {
  33         return __arch_hweight32(w & 0xff);
  34 }
  35
  36 #ifdef CONFIG_X86_32
  37 static inline unsigned long __arch_hweight64(__u64 w)
  38 {
  39         return  __arch_hweight32((u32)w) +
  40                 __arch_hweight32((u32)(w >> 32));
  41 }
  42 #else
  43 static __always_inline unsigned long __arch_hweight64(__u64 w)
  44 {
  45         unsigned long res;
  46
  47         asm (ALTERNATIVE("call __sw_hweight64", "popcntq %1, %0", X86_FEATURE_POPCNT)
  48                          : "="REG_OUT (res)
  49                          : REG_IN (w));
  50
  51         return res;
  52 }
  53 #endif /* CONFIG_X86_32 */
  54
  55 #endif