mpir/mpn/x86_64w/core2/rshift.asm

114 lines
2.7 KiB
NASM

; mpn_rshift
; 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 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.
;
; mpn_rshift(mp_ptr rdi, mp_ptr rsi, mp_size_t rdx, mp_limb_t rcx)
; rcx rdx r8d r9
;
; rax=carry
%include "..\yasm_mac.inc"
%define reg_save_list rbx, rsi, rdi
CPU Athlon64
BITS 64
FRAME_PROC mpn_rshift, 0, reg_save_list
; when n=1 mod4 seem to have different runtimes
movsxd rax, r8d
mov rbx, 4
lea rsi, [rdx+rax*8-24]
lea rdi, [rcx+rax*8-24]
mov rcx, r9
sub rbx, rax
xor rax, rax
mov rdx, [rsi+rbx*8-8]
shrd rax, rdx, cl
cmp rbx, 0
jge L_skiplp
xalign 16
L_lp:
mov r8, [rsi+rbx*8]
mov r11, [rsi+rbx*8+24]
shrd rdx, r8, cl
mov r9, [rsi+rbx*8+8]
shrd r8, r9, cl
mov [rdi+rbx*8-8], rdx
mov [rdi+rbx*8], r8
mov r10, [rsi+rbx*8+16]
shrd r9, r10, cl
mov rdx, r11
mov [rdi+rbx*8+8], r9
shrd r10, r11, cl
add rbx, 4
mov [rdi+rbx*8-16], r10
jnc L_lp
L_skiplp:
cmp rbx, 2
ja L_case0
je L_case1
jp L_case2
L_case3:
mov r8, [rsi+rbx*8]
shrd rdx, r8, cl
mov r9, [rsi+rbx*8+8]
shrd r8, r9, cl
mov [rdi+rbx*8-8], rdx
mov [rdi+rbx*8], r8
mov r10, [rsi+rbx*8+16]
shrd r9, r10, cl
mov [rdi+rbx*8+8], r9
shr r10, cl
mov [rdi+rbx*8+16], r10
jmp L_xit
xalign 16
L_case2:
mov r8, [rsi+rbx*8]
shrd rdx, r8, cl
mov r9, [rsi+rbx*8+8]
shrd r8, r9, cl
mov [rdi+rbx*8-8], rdx
mov [rdi+rbx*8], r8
shr r9, cl
mov [rdi+rbx*8+8], r9
jmp L_xit
xalign 16
L_case1:
mov r8, [rsi+rbx*8]
shrd rdx, r8, cl
shr r8, cl
mov [rdi+rbx*8-8], rdx
mov [rdi+rbx*8], r8
jmp L_xit
xalign 16
L_case0:
shr rdx, cl
mov [rdi+rbx*8-8], rdx
L_xit:
END_PROC reg_save_list
end