diff options
Diffstat (limited to 'arch/x86/include/asm/arch_hweight.h')
| -rw-r--r-- | arch/x86/include/asm/arch_hweight.h | 44 |
1 files changed, 20 insertions, 24 deletions
diff --git a/arch/x86/include/asm/arch_hweight.h b/arch/x86/include/asm/arch_hweight.h index 9686c3d9ff73..b5982b94bdba 100644 --- a/arch/x86/include/asm/arch_hweight.h +++ b/arch/x86/include/asm/arch_hweight.h @@ -1,33 +1,25 @@ +/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_X86_HWEIGHT_H #define _ASM_X86_HWEIGHT_H +#include <asm/cpufeatures.h> + #ifdef CONFIG_64BIT -/* popcnt %edi, %eax -- redundant REX prefix for alignment */ -#define POPCNT32 ".byte 0xf3,0x40,0x0f,0xb8,0xc7" -/* popcnt %rdi, %rax */ -#define POPCNT64 ".byte 0xf3,0x48,0x0f,0xb8,0xc7" #define REG_IN "D" #define REG_OUT "a" #else -/* popcnt %eax, %eax */ -#define POPCNT32 ".byte 0xf3,0x0f,0xb8,0xc0" #define REG_IN "a" #define REG_OUT "a" #endif -/* - * __sw_hweightXX are called from within the alternatives below - * and callee-clobbered registers need to be taken care of. See - * ARCH_HWEIGHT_CFLAGS in <arch/x86/Kconfig> for the respective - * compiler switches. - */ -static inline unsigned int __arch_hweight32(unsigned int w) +static __always_inline unsigned int __arch_hweight32(unsigned int w) { - unsigned int res = 0; + unsigned int res; - asm (ALTERNATIVE("call __sw_hweight32", POPCNT32, X86_FEATURE_POPCNT) - : "="REG_OUT (res) - : REG_IN (w)); + asm_inline (ALTERNATIVE("call __sw_hweight32", + "popcntl %[val], %[cnt]", X86_FEATURE_POPCNT) + : [cnt] "=" REG_OUT (res), ASM_CALL_CONSTRAINT + : [val] REG_IN (w)); return res; } @@ -42,20 +34,24 @@ static inline unsigned int __arch_hweight8(unsigned int w) return __arch_hweight32(w & 0xff); } +#ifdef CONFIG_X86_32 static inline unsigned long __arch_hweight64(__u64 w) { - unsigned long res = 0; - -#ifdef CONFIG_X86_32 return __arch_hweight32((u32)w) + __arch_hweight32((u32)(w >> 32)); +} #else - asm (ALTERNATIVE("call __sw_hweight64", POPCNT64, X86_FEATURE_POPCNT) - : "="REG_OUT (res) - : REG_IN (w)); -#endif /* CONFIG_X86_32 */ +static __always_inline unsigned long __arch_hweight64(__u64 w) +{ + unsigned long res; + + asm_inline (ALTERNATIVE("call __sw_hweight64", + "popcntq %[val], %[cnt]", X86_FEATURE_POPCNT) + : [cnt] "=" REG_OUT (res), ASM_CALL_CONSTRAINT + : [val] REG_IN (w)); return res; } +#endif /* CONFIG_X86_32 */ #endif |