glibc/sysdeps/mips/submul_1.S

100 lines
2.3 KiB
ArmAsm

/* MIPS __mpn_submul_1 -- Multiply a limb vector with a single limb and
subtract the product from a second limb vector.
Copyright (C) 1995, 2000 Free Software Foundation, Inc.
This file is part of the GNU MP Library.
The GNU MP Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Library General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at your
option) any later version.
The GNU MP Library 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 Library General Public
License for more details.
You should have received a copy of the GNU Library General Public License
along with the GNU MP Library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */
#include <sysdep.h>
/* INPUT PARAMETERS
res_ptr $4
s1_ptr $5
size $6
s2_limb $7
*/
#ifdef __PIC__
.option pic2
#endif
ENTRY (__mpn_submul_1)
.set noreorder
#ifdef __PIC__
.cpload t9
#endif
.set nomacro
/* warm up phase 0 */
lw $8,0($5)
/* warm up phase 1 */
addiu $5,$5,4
multu $8,$7
addiu $6,$6,-1
beq $6,$0,$LC0
move $2,$0 /* zero cy2 */
addiu $6,$6,-1
beq $6,$0,$LC1
lw $8,0($5) /* load new s1 limb as early as possible */
Loop: lw $10,0($4)
mflo $3
mfhi $9
addiu $5,$5,4
addu $3,$3,$2 /* add old carry limb to low product limb */
multu $8,$7
lw $8,0($5) /* load new s1 limb as early as possible */
addiu $6,$6,-1 /* decrement loop counter */
sltu $2,$3,$2 /* carry from previous addition -> $2 */
subu $3,$10,$3
sgtu $10,$3,$10
addu $2,$2,$10
sw $3,0($4)
addiu $4,$4,4
bne $6,$0,Loop /* should be "bnel" */
addu $2,$9,$2 /* add high product limb and carry from addition */
/* cool down phase 1 */
$LC1: lw $10,0($4)
mflo $3
mfhi $9
addu $3,$3,$2
sltu $2,$3,$2
multu $8,$7
subu $3,$10,$3
sgtu $10,$3,$10
addu $2,$2,$10
sw $3,0($4)
addiu $4,$4,4
addu $2,$9,$2 /* add high product limb and carry from addition */
/* cool down phase 0 */
$LC0: lw $10,0($4)
mflo $3
mfhi $9
addu $3,$3,$2
sltu $2,$3,$2
subu $3,$10,$3
sgtu $10,$3,$10
addu $2,$2,$10
sw $3,0($4)
j $31
addu $2,$9,$2 /* add high product limb and carry from addition */
END (__mpn_submul_1)