blob: 59ebf7a0020b952c62cece339ea4ac59fa524db2 [file] [log] [blame]
/* HP-PA __udiv_qrnnd division support, used from longlong.h.
* This version runs fast on pre-PA7000 CPUs.
*
* Copyright (C) 1993, 1994, 1998, 2001,
* 2002 Free Software Foundation, Inc.
*
* This file is part of Libgcrypt.
*
* Libgcrypt is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* Libgcrypt is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*
* Note: This code is heavily based on the GNU MP Library.
* Actually it's the same code with only minor changes in the
* way the data is stored; this is to support the abstraction
* of an optional secure memory allocation which may be used
* to avoid revealing of sensitive data due to paging etc.
*/
/* INPUT PARAMETERS
* rem_ptr gr26
* n1 gr25
* n0 gr24
* d gr23
*
* The code size is a bit excessive. We could merge the last two ds;addc
* sequences by simply moving the "bb,< Odd" instruction down. The only
* trouble is the FFFFFFFF code that would need some hacking.
*/
.code
.export __udiv_qrnnd
.label __udiv_qrnnd
.proc
.callinfo frame=0,no_calls
.entry
comb,< %r23,0,L$largedivisor
sub %r0,%r23,%r1 ; clear cy as side-effect
ds %r0,%r1,%r0
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r24
ds %r25,%r23,%r25
addc %r24,%r24,%r28
ds %r25,%r23,%r25
comclr,>= %r25,%r0,%r0
addl %r25,%r23,%r25
stws %r25,0(0,%r26)
bv 0(%r2)
addc %r28,%r28,%r28
.label L$largedivisor
extru %r24,31,1,%r19 ; r19 = n0 & 1
bb,< %r23,31,L$odd
extru %r23,30,31,%r22 ; r22 = d >> 1
shd %r25,%r24,1,%r24 ; r24 = new n0
extru %r25,30,31,%r25 ; r25 = new n1
sub %r0,%r22,%r21
ds %r0,%r21,%r0
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
comclr,>= %r25,%r0,%r0
addl %r25,%r22,%r25
sh1addl %r25,%r19,%r25
stws %r25,0(0,%r26)
bv 0(%r2)
addc %r24,%r24,%r28
.label L$odd
addib,sv,n 1,%r22,L$FF.. ; r22 = (d / 2 + 1)
shd %r25,%r24,1,%r24 ; r24 = new n0
extru %r25,30,31,%r25 ; r25 = new n1
sub %r0,%r22,%r21
ds %r0,%r21,%r0
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r24
ds %r25,%r22,%r25
addc %r24,%r24,%r28
comclr,>= %r25,%r0,%r0
addl %r25,%r22,%r25
sh1addl %r25,%r19,%r25
; We have computed (n1,,n0) / (d + 1), q' = r28, r' = r25
add,nuv %r28,%r25,%r25
addl %r25,%r1,%r25
addc %r0,%r28,%r28
sub,<< %r25,%r23,%r0
addl %r25,%r1,%r25
stws %r25,0(0,%r26)
bv 0(%r2)
addc %r0,%r28,%r28
; This is just a special case of the code above.
; We come here when d == 0xFFFFFFFF
.label L$FF..
add,uv %r25,%r24,%r24
sub,<< %r24,%r23,%r0
ldo 1(%r24),%r24
stws %r24,0(0,%r26)
bv 0(%r2)
addc %r0,%r25,%r28
.exit
.procend