projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| d61931d8 BP |
1 | #ifndef _ASM_X86_HWEIGHT_H |
| 2 | #define _ASM_X86_HWEIGHT_H | |
| 3 | ||
| 4 | #ifdef CONFIG_64BIT | |
| c59bd568 PA |
5 | /* popcnt %edi, %eax -- redundant REX prefix for alignment */ |
| 6 | #define POPCNT32 ".byte 0xf3,0x40,0x0f,0xb8,0xc7" | |
| d61931d8 | 7 | /* popcnt %rdi, %rax */ |
| c59bd568 | 8 | #define POPCNT64 ".byte 0xf3,0x48,0x0f,0xb8,0xc7" |
| d61931d8 BP |
9 | #define REG_IN "D" |
| 10 | #define REG_OUT "a" | |
| 11 | #else | |
| 12 | /* popcnt %eax, %eax */ | |
| c59bd568 | 13 | #define POPCNT32 ".byte 0xf3,0x0f,0xb8,0xc0" |
| d61931d8 BP |
14 | #define REG_IN "a" |
| 15 | #define REG_OUT "a" | |
| 16 | #endif | |
| 17 | ||
| 18 | /* | |
| 19 | * __sw_hweightXX are called from within the alternatives below | |
| 20 | * and callee-clobbered registers need to be taken care of. See | |
| 21 | * ARCH_HWEIGHT_CFLAGS in <arch/x86/Kconfig> for the respective | |
| 22 | * compiler switches. | |
| 23 | */ | |
| 24 | static inline unsigned int __arch_hweight32(unsigned int w) | |
| 25 | { | |
| 26 | unsigned int res = 0; | |
| 27 | ||
| c59bd568 | 28 | asm (ALTERNATIVE("call __sw_hweight32", POPCNT32, X86_FEATURE_POPCNT) |
| d61931d8 BP |
29 | : "="REG_OUT (res) |
| 30 | : REG_IN (w)); | |
| 31 | ||
| 32 | return res; | |
| 33 | } | |
| 34 | ||
| 35 | static inline unsigned int __arch_hweight16(unsigned int w) | |
| 36 | { | |
| 37 | return __arch_hweight32(w & 0xffff); | |
| 38 | } | |
| 39 | ||
| 40 | static inline unsigned int __arch_hweight8(unsigned int w) | |
| 41 | { | |
| 42 | return __arch_hweight32(w & 0xff); | |
| 43 | } | |
| 44 | ||
| 45 | static inline unsigned long __arch_hweight64(__u64 w) | |
| 46 | { | |
| 47 | unsigned long res = 0; | |
| 48 | ||
| 49 | #ifdef CONFIG_X86_32 | |
| 50 | return __arch_hweight32((u32)w) + | |
| 51 | __arch_hweight32((u32)(w >> 32)); | |
| 52 | #else | |
| c59bd568 | 53 | asm (ALTERNATIVE("call __sw_hweight64", POPCNT64, X86_FEATURE_POPCNT) |
| d61931d8 BP |
54 | : "="REG_OUT (res) |
| 55 | : REG_IN (w)); | |
| 56 | #endif /* CONFIG_X86_32 */ | |
| 57 | ||
| 58 | return res; | |
| 59 | } | |
| 60 | ||
| 61 | #endif |