glibc/sysdeps/z8000/sub_n.s
1995-10-16 01:18:40 +00:00

54 lines
1.5 KiB
ArmAsm

! Z8000 __mpn_sub_n -- Subtract two limb vectors of the same length > 0 and
! store difference in a third limb vector.
! Copyright (C) 1993, 1994 Free Software Foundation, Inc.
! This file is part of the GNU MP Library.
! The GNU MP Library is free software; you can redistribute it and/or modify
! it under the terms of the GNU Library General Public License as published by
! the Free Software Foundation; either version 2 of the License, or (at your
! option) any later version.
! The GNU MP 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 Library General Public
! License for more details.
! You should have received a copy of the GNU Library General Public License
! along with the GNU MP Library; see the file COPYING.LIB. If not, write to
! the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
! INPUT PARAMETERS
! res_ptr r7
! s1_ptr r6
! s2_ptr r5
! size r4
! If we are really crazy, we can use push to write a few result words
! backwards, using push just because it is faster than reg+disp. We'd
! then add 2x the number of words written to r7...
unseg
.text
even
global ___mpn_sub_n
___mpn_sub_n:
pop r0,@r6
pop r1,@r5
sub r0,r1
ld @r7,r0
dec r4
jr eq,Lend
Loop: pop r0,@r6
pop r1,@r5
sbc r0,r1
inc r7,#2
ld @r7,r0
dec r4
jr ne,Loop
Lend: ld r2,r4 ! use 0 already in r4
adc r2,r2
ret t