dnl HP-PA 2.0 64-bit mpn_udiv_qrnnd_r.
dnl Copyright 2001-2003 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
This runs at about 280 cycles on both PA8000
and PA8500, corresponding to a
C bit more than 4 cycles/bit.
C INPUT PARAMETERS
define(`n1
',`%r26')
define(`n0
',`%r25')
define(`d
',`%r24')
define(`remptr
',`%r23')
define(`q
',`%r28')
define(`dn
',`%r29')
define(`old_divstep
',
`
add,dc n0,n0,n0
add,dc n1,n1,n1
sub,*<< n1,d,%r22
copy %r22,n1
')
define(`divstep
',
`
add n0,n0,n0
add,dc n1,n1,n1
sub n1,d,%r1
add,dc q,q,q
cmpclr,*<< n1,d,%r0
copy %r1,n1
')
ifdef(`HAVE_ABI_2_0w
',
` .level 2.0w
',` .level 2.0
')
PROLOGUE(mpn_udiv_qrnnd_r)
ifdef(`HAVE_ABI_2_0n
',
` depd %r25,31,32,%r26
depd %r23,31,32,%r24
copy %r24,%r25
ldd -56(%r30),%r24
ldw -60(%r30),%r23
')
ldi 0,q
cmpib,*>= 0,d,L(large_divisor)
ldi 8,%r31 C setup loop counter
sub %r0,d,dn
LDEF(Loop)
divstep divstep divstep divstep divstep divstep divstep divstep
addib,<> -1,%r31,L(Loop)
nop
ifdef(`HAVE_ABI_2_0n
',
` copy %r28,%r29
extrd,u %r28,31,32,%r28
')
bve (%r2)
std n1,0(remptr) C store remainder
LDEF(large_divisor)
extrd,u n0,63,1,%r19 C save lsb of dividend
shrpd n1,n0,1,n0 C n0 = lo(n1n0 >> 1)
shrpd %r0,n1,1,n1 C n1 = hi(n1n0 >> 1)
extrd,u d,63,1,%r20 C save lsb of divisor
shrpd %r0,d,1,d C d = floor(orig_d / 2)
add,l %r20,d,d C d = ceil(orig_d / 2)
sub %r0,d,dn
LDEF(Loop2)
divstep divstep divstep divstep divstep divstep divstep divstep
addib,<> -1,%r31,L(Loop2)
nop
cmpib,*= 0,%r20,L(even_divisor)
shladd n1,1,%r19,n1 C shift in omitted dividend lsb
add d,d,d C restore orig...
sub d,%r20,d C ...d value
sub %r0,d,dn C r21 = -d
add,*nuv n1,q,n1 C fix remainder
for omitted divisor lsb
add,l n1,dn,n1 C adjust remainder
if rem. fix carried
add,dc %r0,q,q C adjust quotient accordingly
sub,*<< n1,d,%r0 C remainder >= divisor?
add,l n1,dn,n1 C adjust remainder
add,dc %r0,q,q C adjust quotient
LDEF(even_divisor)
ifdef(`HAVE_ABI_2_0n
',
` copy %r28,%r29
extrd,u %r28,31,32,%r28
')
bve (%r2)
std n1,0(remptr) C store remainder
EPILOGUE(mpn_udiv_qrnnd_r)
