dnl S/390-64 mpn_addlsh1_n and mpn_rsblsh1_n.
dnl Copyright 2011 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 cycles/limb
C z900 9
C z990 4.75
C z9 ?
C z10 11
C z196 ?
C TODO
C * Optimise for small n, avoid 'la' like in aors_n.asm.
C * Tune to reach 3.5 c/l. For addlsh1, we could let the main alcgr propagate
C carry to the lsh1 alcgr.
C * Compute RETVAL for sublsh1_n less stupidly.
C INPUT PARAMETERS
define(`rp', `%r2')
define(`up', `%r3')
define(`vp', `%r4')
define(`n', `%r5')
ifdef(`OPERATION_addlsh1_n',`
define(ADSB, alg)
define(ADSBC, alcg)
define(INITCY, `lghi %r9, -1')
define(RETVAL, `la %r2, 2(%r1,%r9)')
define(func, mpn_addlsh1_n)
')
ifdef(`OPERATION_rsblsh1_n',`
define(ADSB, slg)
define(ADSBC, slbg)
define(INITCY, `lghi %r9, 0')
define(RETVAL,`dnl
algr %r1, %r9
lghi %r2, 1
algr %r2, %r1')
define(func, mpn_rsblsh1_n)
')
MULFUNC_PROLOGUE(mpn_addlsh1_n mpn_rsblsh1_n)
ASM_START()
PROLOGUE(func)
stmg %r6, %r9, 48(%r15)
aghi n, 3
lghi %r7, 3
srlg %r0, n, 2
ngr %r7, n C n mod 4
je L(b1)
cghi %r7, 2
jl L(b2)
jne L(b0)
L(b3): lmg %r5, %r7, 0(vp)
la vp, 24(vp)
algr %r5, %r5
alcgr %r6, %r6
alcgr %r7, %r7
slbgr %r1, %r1
ADSB %r5, 0(up)
ADSBC %r6, 8(up)
ADSBC %r7, 16(up)
la up, 24(up)
slbgr %r9, %r9
stmg %r5, %r7, 0(rp)
la rp, 24(rp)
brctg %r0, L(top)
j L(end)
L(b0): lghi %r1, -1
INITCY
j L(top)
L(b1): lg %r5, 0(vp)
la vp, 8(vp)
algr %r5, %r5
slbgr %r1, %r1
ADSB %r5, 0(up)
la up, 8(up)
slbgr %r9, %r9
stg %r5, 0(rp)
la rp, 8(rp)
brctg %r0, L(top)
j L(end)
L(b2): lmg %r5, %r6, 0(vp)
la vp, 16(vp)
algr %r5, %r5
alcgr %r6, %r6
slbgr %r1, %r1
ADSB %r5, 0(up)
ADSBC %r6, 8(up)
la up, 16(up)
slbgr %r9, %r9
stmg %r5, %r6, 0(rp)
la rp, 16(rp)
brctg %r0, L(top)
j L(end)
L(top): lmg %r5, %r8, 0(vp)
la vp, 32(vp)
aghi %r1, 1 C restore carry
alcgr %r5, %r5
alcgr %r6, %r6
alcgr %r7, %r7
alcgr %r8, %r8
slbgr %r1, %r1 C save carry
aghi %r9, 1 C restore carry
ADSBC %r5, 0(up)
ADSBC %r6, 8(up)
ADSBC %r7, 16(up)
ADSBC %r8, 24(up)
la up, 32(up)
slbgr %r9, %r9 C save carry
stmg %r5, %r8, 0(rp)
la rp, 32(rp)
brctg %r0, L(top)
L(end): RETVAL
lmg %r6, %r9, 48(%r15)
br %r14
EPILOGUE()