dnl IBM POWER mpn_add_n --
Add two limb vectors of equal, non-zero length.
dnl Copyright 1992, 1994-1996, 1999-2001, 2005 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
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dnl INPUT PARAMETERS
dnl res_ptr r3
dnl s1_ptr r4
dnl s2_ptr r5
dnl size r6
include(`../config.m4
')
ASM_START()
PROLOGUE(mpn_add_n)
andil. 10,6,1 C odd
or even number of limbs?
l 8,0(4) C load least significant s1 limb
l 0,0(5) C load least significant s2 limb
cal 3,-4(3) C offset res_ptr, it
's updated before it's used
sri 10,6,1 C count
for unrolled loop
a 7,0,8 C
add least significant limbs, set cy
mtctr 10 C copy count into CTR
beq 0,Leven C branch
if even # of limbs (# of limbs >= 2)
C We have an odd # of limbs.
Add the first limbs separately.
cmpi 1,10,0 C is count
for unrolled loop
zero?
bc 4,6,L1 C bne cr1,L1 (misassembled by gas)
st 7,4(3)
aze 3,10 C use the fact that r10 is
zero...
br C return
C We added least significant limbs. Now reload the next limbs to enter loop.
L1: lu 8,4(4) C load s1 limb
and update s1_ptr
lu 0,4(5) C load s2 limb
and update s2_ptr
stu 7,4(3)
ae 7,0,8 C
add limbs, set cy
Leven: lu 9,4(4) C load s1 limb
and update s1_ptr
lu 10,4(5) C load s2 limb
and update s2_ptr
bdz Lend C
If done, skip loop
Loop: lu 8,4(4) C load s1 limb
and update s1_ptr
lu 0,4(5) C load s2 limb
and update s2_ptr
ae 11,10,9 C
add previous limbs with cy, set cy
stu 7,4(3) C
lu 9,4(4) C load s1 limb
and update s1_ptr
lu 10,4(5) C load s2 limb
and update s2_ptr
ae 7,0,8 C
add previous limbs with cy, set cy
stu 11,4(3) C
bdn Loop C decrement CTR
and loop back
Lend: ae 11,10,9 C
add limbs with cy, set cy
st 7,4(3) C
st 11,8(3) C
lil 3,0 C load cy into ...
aze 3,3 C ... return value register
br
EPILOGUE(mpn_add_n)
