mpir/mpn/x86_64w/amd64/lshift1.asm

121 lines
2.8 KiB
NASM

; AMD64 mpn_lshift1 -- mpn right shift by 1
; Version 1.0.4.
;
; Copyright 2008 Jason Moxham
;
; Windows Conversion Copyright 2008 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.
;
; Calling interface:
;
; mp_limb_t mpn_lshift1(
; mp_ptr dst, rcx
; mp_srcptr src, rdx
; mp_size_t size, r8
; )
;
; This is an SEH leaf function (no unwind support needed)
%include "..\yasm_mac.inc"
%define reg_save_list r12, r13
BITS 64
FRAME_PROC mpn_lshift1, 0, reg_save_list
movsxd r8, r8d
xor rax, rax
mov r9, r8
and r9, 7
inc r9
shr r8, 3
; and clear carry flag
cmp r8, 0
jz .2
alignb 16, nop
.1: mov r10, [rdx]
mov r11, [rdx+8]
mov r12, [rdx+16]
mov r13, [rdx+24]
adc r10, r10
adc r11, r11
adc r12, r12
adc r13, r13
mov [rcx], r10
mov [rcx+8], r11
mov [rcx+16], r12
mov [rcx+24], r13
mov r10, [rdx+32]
mov r11, [rdx+40]
mov r12, [rdx+48]
mov r13, [rdx+56]
adc r10, r10
adc r11, r11
adc r12, r12
adc r13, r13
mov [rcx+32], r10
mov [rcx+40], r11
mov [rcx+48], r12
mov [rcx+56], r13
lea rcx, [rcx+64]
dec r8
lea rdx, [rdx+64]
jnz .1
.2:
dec r9
jz .3
; Could still have cache-bank conflicts in this tail part
mov r10, [rdx]
adc r10, r10
mov [rcx], r10
dec r9
jz .3
mov r10, [rdx+8]
adc r10, r10
mov [rcx+8], r10
dec r9
jz .3
mov r10, [rdx+16]
adc r10, r10
mov [rcx+16], r10
dec r9
jz .3
mov r10, [rdx+24]
adc r10, r10
mov [rcx+24], r10
dec r9
jz .3
mov r10, [rdx+32]
adc r10, r10
mov [rcx+32], r10
dec r9
jz .3
mov r10, [rdx+40]
adc r10, r10
mov [rcx+40], r10
dec r9
jz .3
mov r10, [rdx+48]
adc r10, r10
mov [rcx+48], r10
.3:
adc rax, rax
END_PROC reg_save_list
end