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/* Alpha 21064 __udiv_qrnnd
*
* Copyright (C) 1992, 1994, 1995, 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.
*/
.set noreorder
.set noat
.text
.align 3
.globl __udiv_qrnnd
.ent __udiv_qrnnd
__udiv_qrnnd:
.frame $30,0,$26,0
.prologue 0
#define cnt $2
#define tmp $3
#define rem_ptr $16
#define n1 $17
#define n0 $18
#define d $19
#define qb $20
ldiq cnt,16
blt d,.Largedivisor
.Loop1: cmplt n0,0,tmp
addq n1,n1,n1
bis n1,tmp,n1
addq n0,n0,n0
cmpule d,n1,qb
subq n1,d,tmp
cmovne qb,tmp,n1
bis n0,qb,n0
cmplt n0,0,tmp
addq n1,n1,n1
bis n1,tmp,n1
addq n0,n0,n0
cmpule d,n1,qb
subq n1,d,tmp
cmovne qb,tmp,n1
bis n0,qb,n0
cmplt n0,0,tmp
addq n1,n1,n1
bis n1,tmp,n1
addq n0,n0,n0
cmpule d,n1,qb
subq n1,d,tmp
cmovne qb,tmp,n1
bis n0,qb,n0
cmplt n0,0,tmp
addq n1,n1,n1
bis n1,tmp,n1
addq n0,n0,n0
cmpule d,n1,qb
subq n1,d,tmp
cmovne qb,tmp,n1
bis n0,qb,n0
subq cnt,1,cnt
bgt cnt,.Loop1
stq n1,0(rem_ptr)
bis $31,n0,$0
ret $31,($26),1
.Largedivisor:
and n0,1,$4
srl n0,1,n0
sll n1,63,tmp
or tmp,n0,n0
srl n1,1,n1
and d,1,$6
srl d,1,$5
addq $5,$6,$5
.Loop2: cmplt n0,0,tmp
addq n1,n1,n1
bis n1,tmp,n1
addq n0,n0,n0
cmpule $5,n1,qb
subq n1,$5,tmp
cmovne qb,tmp,n1
bis n0,qb,n0
cmplt n0,0,tmp
addq n1,n1,n1
bis n1,tmp,n1
addq n0,n0,n0
cmpule $5,n1,qb
subq n1,$5,tmp
cmovne qb,tmp,n1
bis n0,qb,n0
cmplt n0,0,tmp
addq n1,n1,n1
bis n1,tmp,n1
addq n0,n0,n0
cmpule $5,n1,qb
subq n1,$5,tmp
cmovne qb,tmp,n1
bis n0,qb,n0
cmplt n0,0,tmp
addq n1,n1,n1
bis n1,tmp,n1
addq n0,n0,n0
cmpule $5,n1,qb
subq n1,$5,tmp
cmovne qb,tmp,n1
bis n0,qb,n0
subq cnt,1,cnt
bgt cnt,.Loop2
addq n1,n1,n1
addq $4,n1,n1
bne $6,.LOdd
stq n1,0(rem_ptr)
bis $31,n0,$0
ret $31,($26),1
.LOdd:
/* q' in n0. r' in n1 */
addq n1,n0,n1
cmpult n1,n0,tmp # tmp := carry from addq
beq tmp,.LLp6
addq n0,1,n0
subq n1,d,n1
.LLp6: cmpult n1,d,tmp
bne tmp,.LLp7
addq n0,1,n0
subq n1,d,n1
.LLp7:
stq n1,0(rem_ptr)
bis $31,n0,$0
ret $31,($26),1
.end __udiv_qrnnd