mpir/mpn/sparc32/rshift.asm

94 lines
2.0 KiB
NASM
Raw Normal View History

dnl SPARC mpn_rshift -- Shift a number right.
dnl Copyright 1995, 1996, 2000 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 %o0
C src_ptr %o1
C size %o2
C cnt %o3
ASM_START()
PROLOGUE(mpn_rshift)
ld [%o1],%g2 C load first limb
sub %g0,%o3,%o5 C negate shift count
add %o2,-1,%o2
andcc %o2,4-1,%g4 C number of limbs in first loop
sll %g2,%o5,%g1 C compute function result
be L(0) C if multiple of 4 limbs, skip first loop
st %g1,[%sp+80]
sub %o2,%g4,%o2 C adjust count for main loop
L(loop0):
ld [%o1+4],%g3
add %o0,4,%o0
add %o1,4,%o1
addcc %g4,-1,%g4
srl %g2,%o3,%o4
sll %g3,%o5,%g1
mov %g3,%g2
or %o4,%g1,%o4
bne L(loop0)
st %o4,[%o0-4]
L(0): tst %o2
be L(end)
nop
L(loop):
ld [%o1+4],%g3
add %o0,16,%o0
addcc %o2,-4,%o2
srl %g2,%o3,%o4
sll %g3,%o5,%g1
ld [%o1+8],%g2
srl %g3,%o3,%g4
or %o4,%g1,%o4
st %o4,[%o0-16]
sll %g2,%o5,%g1
ld [%o1+12],%g3
srl %g2,%o3,%o4
or %g4,%g1,%g4
st %g4,[%o0-12]
sll %g3,%o5,%g1
ld [%o1+16],%g2
srl %g3,%o3,%g4
or %o4,%g1,%o4
st %o4,[%o0-8]
sll %g2,%o5,%g1
add %o1,16,%o1
or %g4,%g1,%g4
bne L(loop)
st %g4,[%o0-4]
L(end): srl %g2,%o3,%g2
st %g2,[%o0-0]
retl
ld [%sp+80],%o0
EPILOGUE(mpn_rshift)