dnl AMD64 mpn_popcount -- population count.
dnl Copyright 2017 Free Software Foundation,
Inc.
dnl
This file is part of the GNU MP Library.
dnl
dnl The GNU MP Library is free software
; you can redistribute it and/or modify
dnl it under the terms of either:
dnl
dnl * the GNU Lesser General
Public License as published by the Free
dnl Software Foundation
; either version 3 of the License, or (at your
dnl
option) any later
version.
dnl
dnl
or
dnl
dnl * the GNU General
Public License as published by the Free Software
dnl Foundation
; either version 2 of the License, or (at your option) any
dnl later
version.
dnl
dnl
or both in parallel, as here.
dnl
dnl The GNU MP Library is distributed in the hope that it will be useful, but
dnl WITHOUT ANY WARRANTY
; without even the implied warranty of MERCHANTABILITY
dnl
or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General
Public License
dnl
for more details.
dnl
dnl You should have received copies of the GNU General
Public License
and the
dnl GNU Lesser General
Public License along with the GNU MP Library.
If not,
dnl see
https://www.gnu.org/licenses/.
include(`../config.m4
')
C cycles/limb
C AMD K8,K9 n/a
C AMD K10 1.39
C AMD bd1 4
C AMD bd2 4
C AMD bd3 ?
C AMD bd4 ?
C AMD zen 0.72
C AMD bobcat 5.78
C AMD jaguar 1.27
C Intel P4 n/a
C Intel core2 n/a
C Intel NHM 1.04
C Intel SBR 1.02
C Intel IBR 1.0
C Intel HWL 1.0
C Intel BWL 1.0
C Intel SKL 1.0
C Intel atom n/a
C Intel SLM 1.34
C VIA nano n/a
C TODO
C * We could approach 0.5 c/l
for AMD Zen with more unrolling. That would
C not cause any additional feed-in overhead as we already use a jump table.
C * An AVX pshufb based variant should approach 0.5 c/l on Haswell
and later
C Intel hardware. Perhaps mix such a loop with popcnt instructions.
C * The random placement of the L0, L1, L2, etc blocks are due to branch
C shortening.
define(`up
', `%rdi')
define(`n
', `%rsi')
ABI_SUPPORT(DOS64)
ABI_SUPPORT(STD64)
ASM_START()
TEXT
ALIGN(32)
PROLOGUE(mpn_popcount)
FUNC_ENTRY(2)
mov R32(n), R32(%r8)
and $7, R32(%r8)
.
byte 0xf3,0x48,0x0f,0xb8,0x07 C popcnt (up), %rax
xor R32(%rcx), R32(%rcx)
lea L(tab)(%rip), %r9
ifdef(`PIC
',`
movslq (%r9,%r8,4), %r8
add %r9, %r8
jmp *%r8
',`
jmp *(%r9,%r8,8)
')
L(3): .
byte 0xf3,0x4c,0x0f,0xb8,0x57,0x08 C popcnt 8(up), %r10
.
byte 0xf3,0x4c,0x0f,0xb8,0x5f,0x10 C popcnt 16(up), %r11
add $24, up
sub $8, n
jg L(e34)
add %r10, %rax
add %r11, %rax
L(s1): FUNC_EXIT()
ret
L(1):
sub $8, n
jle L(s1)
.
byte 0xf3,0x4c,0x0f,0xb8,0x47,0x08 C popcnt 8(up), %r8
.
byte 0xf3,0x4c,0x0f,0xb8,0x4f,0x10 C popcnt 16(up), %r9
add $8, up
jmp L(e12)
L(7): .
byte 0xf3,0x4c,0x0f,0xb8,0x57,0x08 C popcnt 0x8(%rdi),%r10
.
byte 0xf3,0x4c,0x0f,0xb8,0x5f,0x10 C popcnt 0x10(%rdi),%r11
add $-8, up
jmp L(e07)
L(0): .
byte 0xf3,0x48,0x0f,0xb8,0x4f,0x08 C popcnt 0x8(%rdi),%rcx
.
byte 0xf3,0x4c,0x0f,0xb8,0x57,0x10 C popcnt 0x10(%rdi),%r10
.
byte 0xf3,0x4c,0x0f,0xb8,0x5f,0x18 C popcnt 0x18(%rdi),%r11
jmp L(e07)
L(4): .
byte 0xf3,0x48,0x0f,0xb8,0x4f,0x08 C popcnt 0x8(%rdi),%rcx
.
byte 0xf3,0x4c,0x0f,0xb8,0x57,0x10 C popcnt 0x10(%rdi),%r10
.
byte 0xf3,0x4c,0x0f,0xb8,0x5f,0x18 C popcnt 0x18(%rdi),%r11
add $32, up
sub $8, n
jle L(x4)
ALIGN(16)
L(top):
L(e34): .
byte 0xf3,0x4c,0x0f,0xb8,0x07 C popcnt (%rdi),%r8
.
byte 0xf3,0x4c,0x0f,0xb8,0x4f,0x08 C popcnt 0x8(%rdi),%r9
add %r10, %rcx
add %r11, %rax
L(e12): .
byte 0xf3,0x4c,0x0f,0xb8,0x57,0x10 C popcnt 0x10(%rdi),%r10
.
byte 0xf3,0x4c,0x0f,0xb8,0x5f,0x18 C popcnt 0x18(%rdi),%r11
add %r8, %rcx
add %r9, %rax
L(e07): .
byte 0xf3,0x4c,0x0f,0xb8,0x47,0x20 C popcnt 0x20(%rdi),%r8
.
byte 0xf3,0x4c,0x0f,0xb8,0x4f,0x28 C popcnt 0x28(%rdi),%r9
add %r10, %rcx
add %r11, %rax
L(e56): .
byte 0xf3,0x4c,0x0f,0xb8,0x57,0x30 C popcnt 0x30(%rdi),%r10
.
byte 0xf3,0x4c,0x0f,0xb8,0x5f,0x38 C popcnt 0x38(%rdi),%r11
add $64, up
add %r8, %rcx
add %r9, %rax
sub $8, n
jg L(top)
L(x4):
add %r10, %rcx
add %r11, %rax
L(x2):
add %rcx, %rax
FUNC_EXIT()
ret
L(2): .
byte 0xf3,0x48,0x0f,0xb8,0x4f,0x08 C popcnt 0x8(%rdi),%rcx
sub $8, n
jle L(x2)
.
byte 0xf3,0x4c,0x0f,0xb8,0x47,0x10 C popcnt 0x10(%rdi),%r8
.
byte 0xf3,0x4c,0x0f,0xb8,0x4f,0x18 C popcnt 0x18(%rdi),%r9
add $16, up
jmp L(e12)
L(5): .
byte 0xf3,0x4c,0x0f,0xb8,0x47,0x08 C popcnt 0x8(%rdi),%r8
.
byte 0xf3,0x4c,0x0f,0xb8,0x4f,0x10 C popcnt 0x10(%rdi),%r9
add $-24, up
jmp L(e56)
L(6): .
byte 0xf3,0x48,0x0f,0xb8,0x4f,0x08 C popcnt 0x8(%rdi),%rcx
.
byte 0xf3,0x4c,0x0f,0xb8,0x47,0x10 C popcnt 0x10(%rdi),%r8
.
byte 0xf3,0x4c,0x0f,0xb8,0x4f,0x18 C popcnt 0x18(%rdi),%r9
add $-16, up
jmp L(e56)
EPILOGUE()
JUMPTABSECT
ALIGN(8)
L(tab): JMPENT( L(0), L(tab))
JMPENT( L(1), L(tab))
JMPENT( L(2), L(tab))
JMPENT( L(3), L(tab))
JMPENT( L(4), L(tab))
JMPENT( L(5), L(tab))
JMPENT( L(6), L(tab))
JMPENT( L(7), L(tab))
