/* SPDX-License-Identifier: GPL-2.0 */
|
#include <linux/linkage.h>
|
#include <asm/export.h>
|
|
#include <asm/asm.h>
|
|
/*
|
* unsigned int __sw_hweight32(unsigned int w)
|
* %rdi: w
|
*/
|
SYM_FUNC_START(__sw_hweight32)
|
|
#ifdef CONFIG_X86_64
|
movl %edi, %eax # w
|
#endif
|
__ASM_SIZE(push,) %__ASM_REG(dx)
|
movl %eax, %edx # w -> t
|
shrl %edx # t >>= 1
|
andl $0x55555555, %edx # t &= 0x55555555
|
subl %edx, %eax # w -= t
|
|
movl %eax, %edx # w -> t
|
shrl $2, %eax # w_tmp >>= 2
|
andl $0x33333333, %edx # t &= 0x33333333
|
andl $0x33333333, %eax # w_tmp &= 0x33333333
|
addl %edx, %eax # w = w_tmp + t
|
|
movl %eax, %edx # w -> t
|
shrl $4, %edx # t >>= 4
|
addl %edx, %eax # w_tmp += t
|
andl $0x0f0f0f0f, %eax # w_tmp &= 0x0f0f0f0f
|
imull $0x01010101, %eax, %eax # w_tmp *= 0x01010101
|
shrl $24, %eax # w = w_tmp >> 24
|
__ASM_SIZE(pop,) %__ASM_REG(dx)
|
RET
|
SYM_FUNC_END(__sw_hweight32)
|
EXPORT_SYMBOL(__sw_hweight32)
|
|
SYM_FUNC_START(__sw_hweight64)
|
#ifdef CONFIG_X86_64
|
pushq %rdi
|
pushq %rdx
|
|
movq %rdi, %rdx # w -> t
|
movabsq $0x5555555555555555, %rax
|
shrq %rdx # t >>= 1
|
andq %rdx, %rax # t &= 0x5555555555555555
|
movabsq $0x3333333333333333, %rdx
|
subq %rax, %rdi # w -= t
|
|
movq %rdi, %rax # w -> t
|
shrq $2, %rdi # w_tmp >>= 2
|
andq %rdx, %rax # t &= 0x3333333333333333
|
andq %rdi, %rdx # w_tmp &= 0x3333333333333333
|
addq %rdx, %rax # w = w_tmp + t
|
|
movq %rax, %rdx # w -> t
|
shrq $4, %rdx # t >>= 4
|
addq %rdx, %rax # w_tmp += t
|
movabsq $0x0f0f0f0f0f0f0f0f, %rdx
|
andq %rdx, %rax # w_tmp &= 0x0f0f0f0f0f0f0f0f
|
movabsq $0x0101010101010101, %rdx
|
imulq %rdx, %rax # w_tmp *= 0x0101010101010101
|
shrq $56, %rax # w = w_tmp >> 56
|
|
popq %rdx
|
popq %rdi
|
RET
|
#else /* CONFIG_X86_32 */
|
/* We're getting an u64 arg in (%eax,%edx): unsigned long hweight64(__u64 w) */
|
pushl %ecx
|
|
call __sw_hweight32
|
movl %eax, %ecx # stash away result
|
movl %edx, %eax # second part of input
|
call __sw_hweight32
|
addl %ecx, %eax # result
|
|
popl %ecx
|
RET
|
#endif
|
SYM_FUNC_END(__sw_hweight64)
|
EXPORT_SYMBOL(__sw_hweight64)
|
