dnl S/390-64 mpn_mul_basecase.
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 ?
C z990 23
C z9 ?
C z10 28
C z196 ?
C TODO
C * Perhaps add special case for un <= 2.
C * Replace loops by faster code. The mul_1 and addmul_1 loops could be sped
C up by about 10%.
C INPUT PARAMETERS
define(`rp', `%r2')
define(`up', `%r3')
define(`un', `%r4')
define(`vp', `%r5')
define(`vn', `%r6')
define(`zero', `%r8')
ASM_START()
PROLOGUE(mpn_mul_basecase)
cghi un, 2
jhe L(ge2)
C un = vn = 1
lg %r1, 0(vp)
mlg %r0, 0(up)
stg %r1, 0(rp)
stg %r0, 8(rp)
br %r14
L(ge2): C jne L(gen)
L(gen):
C mul_1 =======================================================================
stmg %r6, %r12, 48(%r15)
lghi zero, 0
aghi un, -1
lg %r7, 0(vp)
lg %r11, 0(up)
lghi %r12, 8 C init index register
mlgr %r10, %r7
lgr %r9, un
stg %r11, 0(rp)
cr %r15, %r15 C clear carry flag
L(tm): lg %r1, 0(%r12,up)
mlgr %r0, %r7
alcgr %r1, %r10
lgr %r10, %r0 C copy high part to carry limb
stg %r1, 0(%r12,rp)
la %r12, 8(%r12)
brctg %r9, L(tm)
alcgr %r0, zero
stg %r0, 0(%r12,rp)
C addmul_1 loop ===============================================================
aghi vn, -1
je L(outer_end)
L(outer_loop):
la rp, 8(rp) C rp += 1
la vp, 8(vp) C up += 1
lg %r7, 0(vp)
lg %r11, 0(up)
lghi %r12, 8 C init index register
mlgr %r10, %r7
lgr %r9, un
alg %r11, 0(rp)
stg %r11, 0(rp)
L(tam): lg %r1, 0(%r12,up)
lg %r11, 0(%r12,rp)
mlgr %r0, %r7
alcgr %r1, %r11
alcgr %r0, zero
algr %r1, %r10
lgr %r10, %r0
stg %r1, 0(%r12,rp)
la %r12, 8(%r12)
brctg %r9, L(tam)
alcgr %r0, zero
stg %r0, 0(%r12,rp)
brctg vn, L(outer_loop)
L(outer_end):
lmg %r6, %r12, 48(%r15)
br %r14
EPILOGUE()