mpir/mpn/x86_64w/divexact_by3c.asm
2012-07-12 12:47:59 +00:00

100 lines
2.6 KiB
NASM

; PROLOGUE(divexact_by3c)
; Version 1.0.4.
;
; Copyright 2008 Jason Moxham and Brian Gladman
;
; 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 version 2.1 of the License, or (at
; your option) any later version.
; 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.
;
; mp_limb_t mpn_divexact_by3c(mp_ptr, mp_ptr, mp_size_t, mp_limb_t)
; mp_limb_t mpn_divexact_by3(mp_ptr, mp_ptr, mp_size_t)
; rax rdi rsi rdx rcx
; rax rcx rdx r8 r9
%include "yasm_mac.inc"
BITS 64
%define MLT1 0x5555555555555555
xalign 16
LEAF_PROC mpn_divexact_by3c
mov rax, r8
mov r8, MLT1
imul r9, r8
jmp entry
xalign 16
LEAF_PROC mpn_divexact_by3
mov rax, r8
mov r8, MLT1
xor r9, r9
entry:
lea r10, [rdx+rax*8-24]
lea r11, [rcx+rax*8-24]
mov ecx, 3
sub rcx, rax
jnc .2
xalign 16
.1: mov rax, [r10+rcx*8]
mul r8
sub r9, rax
mov [r11+rcx*8], r9
sbb r9, rdx
mov rax, [r10+rcx*8+8]
mul r8
sub r9, rax
mov [r11+rcx*8+8], r9
sbb r9, rdx
mov rax, [r10+rcx*8+16]
mul r8
sub r9, rax
mov [r11+rcx*8+16], r9
sbb r9, rdx
mov rax, [r10+rcx*8+24]
mul r8
sub r9, rax
mov [r11+rcx*8+24], r9
sbb r9, rdx
add rcx, 4
jnc .1
.2: test rcx, 2
jnz .3
mov rax, [r10+rcx*8]
mul r8
sub r9, rax
mov [r11+rcx*8], r9
sbb r9, rdx
mov rax, [r10+rcx*8+8]
mul r8
sub r9, rax
mov [r11+rcx*8+8], r9
sbb r9, rdx
add rcx, 2
.3: test rcx, 1
jnz .4
mov rax, [r10+rcx*8]
mul r8
sub r9, rax
mov [r11+rcx*8], r9
sbb r9, rdx
.4: lea rax, [r9+r9*2]
neg rax
ret
end