63 lines
2.2 KiB
NASM
63 lines
2.2 KiB
NASM
dnl PowerPC-64 mpn_sub_n -- Subtract two limb vectors of the same length > 0
|
|
dnl and store difference in a third limb vector.
|
|
|
|
dnl Copyright 1999, 2000, 2001 Free Software Foundation, Inc.
|
|
|
|
dnl This file is part of the GNU MP Library.
|
|
|
|
dnl The GNU MP Library is free software; you can redistribute it and/or modify
|
|
dnl it under the terms of the GNU Lesser General Public License as published
|
|
dnl by the Free Software Foundation; either version 2.1 of the License, or (at
|
|
dnl your option) any later version.
|
|
|
|
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 Lesser General Public
|
|
dnl License for more details.
|
|
|
|
dnl You should have received a copy of the GNU Lesser General Public License
|
|
dnl along with the GNU MP Library; see the file COPYING.LIB. If not, write
|
|
dnl to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
|
|
dnl Boston, MA 02110-1301, USA.
|
|
|
|
include(`../config.m4')
|
|
|
|
C INPUT PARAMETERS
|
|
C res_ptr r3
|
|
C s1_ptr r4
|
|
C s2_ptr r5
|
|
C size r6
|
|
|
|
C This code runs at 1.5 cycles/limb on the PPC630.
|
|
|
|
ASM_START()
|
|
PROLOGUE(mpn_sub_n)
|
|
mtctr r6 C copy size into CTR
|
|
addic r0,r6,-1 C set cy
|
|
ld r8,0(r4) C load least significant s1 limb
|
|
ld r0,0(r5) C load least significant s2 limb
|
|
addi r3,r3,-8 C offset res_ptr, it's updated before it's used
|
|
bdz L(eno) C If done, skip loop
|
|
L(top): ld r9,8(r4) C load s1 limb
|
|
ld r10,8(r5) C load s2 limb
|
|
subfe r7,r0,r8 C subtract limbs with cy, set cy
|
|
std r7,8(r3) C store result limb
|
|
bdz L(ene) C decrement CTR and exit if done
|
|
ldu r8,16(r4) C load s1 limb and update s1_ptr
|
|
ldu r0,16(r5) C load s2 limb and update s2_ptr
|
|
subfe r7,r10,r9 C subtract limbs with cy, set cy
|
|
stdu r7,16(r3) C store result limb and update res_ptr
|
|
bdnz L(top) C decrement CTR and loop back
|
|
|
|
L(eno): subfe r7,r0,r8
|
|
std r7,8(r3) C store ultimate result limb
|
|
subfe r3,r0,r0 C load !cy into ...
|
|
subfic r3,r3,0 C ... return value register
|
|
blr
|
|
L(ene): subfe r7,r10,r9
|
|
std r7,16(r3)
|
|
subfe r3,r0,r0 C load !cy into ...
|
|
subfic r3,r3,0 C ... return value register
|
|
blr
|
|
EPILOGUE(mpn_sub_n)
|