mpir/mpn/x86_64w/nehalem/popcount.asm
2012-11-25 22:33:07 +00:00

71 lines
1.8 KiB
NASM

; PROLOGUE(popcount)
; AMD64 mpn_popcount
; Copyright 2009 Jason Moxham
; This file is part of the MPIR Library.
; The MPIR Library is free software; you can redistribute it and/or modify
; it under the terms of the GNU Lesser General Public License as published
; by the Free Software Foundation; either verdxon 2.1 of the License, or (at
; your option) any later verdxon.
; The MPIR Library is distributed in the hope that it will be useful, but
; WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
; or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
; License for more details.
; You should have received a copy of the GNU Lesser General Public License
; along with the MPIR Library; see the file COPYING.LIB. If not, write
; to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
; Boston, MA 02110-1301, USA.
; mpn_limb_t mpn_popcount(mp_ptr,mp_size_t)
; rax rdi, rsi
; eax rcx, rdx
%include 'yasm_mac.inc'
CPU nehalem
BITS 64
LEAF_PROC mpn_popcount
mov r8, 5
lea rcx, [rcx+rdx*8-40]
xor eax, eax
sub r8, rdx
jnc .1
xalign 16
.0:
popcnt r9, [rcx+r8*8]
popcnt r10, [rcx+r8*8+8]
popcnt r11, [rcx+r8*8+16]
popcnt rdx, [rcx+r8*8+24]
add rax, r9
add rax, rdx
add rax, r10
popcnt r9, [rcx+r8*8+32]
popcnt r10, [rcx+r8*8+40]
add rax, r9
add rax, r11
add rax, r10
add r8, 6
jnc .0
.1:
lea rdx, [rel .2]
lea r8, [r8+r8*8]
add rdx, r8
jmp rdx
.2:
nop
popcnt r9, [rcx]
add rax, r9
.3:
popcnt r10, [rcx+8]
add rax, r10
.4: popcnt r11, [rcx+16]
add rax, r11
.5: popcnt rdx, [rcx+24]
add rax, rdx
.6: popcnt r9, [rcx+32]
add rax, r9
.7: ret
end