dnl HP-PA 2.0 32-bit mpn_sub_n -- Subtract two limb vectors of the same
dnl length > 0 and store difference in a third limb vector.
dnl Copyright 1997, 1998, 2000-2002 Free Software Foundation, Inc.
dnl This file is part of the GNU MP Library.
dnl
dnl The GNU MP Library is free software; you can redistribute it and/or modify
dnl it under the terms of either:
dnl
dnl * the GNU Lesser General Public License as published by the Free
dnl Software Foundation; either version 3 of the License, or (at your
dnl option) any later version.
dnl
dnl or
dnl
dnl * the GNU General Public License as published by the Free Software
dnl Foundation; either version 2 of the License, or (at your option) any
dnl later version.
dnl
dnl or both in parallel, as here.
dnl
dnl The GNU MP Library is distributed in the hope that it will be useful, but
dnl WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
dnl or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
dnl for more details.
dnl
dnl You should have received copies of the GNU General Public License and the
dnl GNU Lesser General Public License along with the GNU MP Library. If not,
dnl see https://www.gnu.org/licenses/.
include(`../config.m4')
C INPUT PARAMETERS
C res_ptr gr26
C s1_ptr gr25
C s2_ptr gr24
C size gr23
C This runs at 2 cycles/limb on PA8000.
ASM_START()
PROLOGUE(mpn_sub_n)
sub %r0,%r23,%r22
zdep %r22,30,3,%r28 C r28 = 2 * (-n & 7)
zdep %r22,29,3,%r22 C r22 = 4 * (-n & 7)
sub %r25,%r22,%r25 C offset s1_ptr
sub %r24,%r22,%r24 C offset s2_ptr
blr %r28,%r0 C branch into loop
sub %r26,%r22,%r26 C offset res_ptr and set carry
LDEF(loop)
ldw 0(%r25),%r20
ldw 0(%r24),%r31
subb %r20,%r31,%r20
stw %r20,0(%r26)
LDEF(7)
ldw 4(%r25),%r21
ldw 4(%r24),%r19
subb %r21,%r19,%r21
stw %r21,4(%r26)
LDEF(6)
ldw 8(%r25),%r20
ldw 8(%r24),%r31
subb %r20,%r31,%r20
stw %r20,8(%r26)
LDEF(5)
ldw 12(%r25),%r21
ldw 12(%r24),%r19
subb %r21,%r19,%r21
stw %r21,12(%r26)
LDEF(4)
ldw 16(%r25),%r20
ldw 16(%r24),%r31
subb %r20,%r31,%r20
stw %r20,16(%r26)
LDEF(3)
ldw 20(%r25),%r21
ldw 20(%r24),%r19
subb %r21,%r19,%r21
stw %r21,20(%r26)
LDEF(2)
ldw 24(%r25),%r20
ldw 24(%r24),%r31
subb %r20,%r31,%r20
stw %r20,24(%r26)
LDEF(1)
ldw 28(%r25),%r21
ldo 32(%r25),%r25
ldw 28(%r24),%r19
subb %r21,%r19,%r21
stw %r21,28(%r26)
ldo 32(%r24),%r24
addib,> -8,%r23,L(loop)
ldo 32(%r26),%r26
addc %r0,%r0,%r28
bv (%r2)
subi 1,%r28,%r28
EPILOGUE()