libgcrypt-1.4.6/mpi/sparc32/mpih-lshift.S

/* sparc lshift
 *
 *      Copyright (C) 1995, 1996, 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
 */


! INPUT PARAMETERS
! res_ptr	%o0
! src_ptr	%o1
! size		%o2
! cnt		%o3

#include "sysdep.h"

	.text
	.align	4
	.global C_SYMBOL_NAME(_gcry_mpih_lshift)
C_SYMBOL_NAME(_gcry_mpih_lshift):
	sll	%o2,2,%g1
	add	%o1,%g1,%o1	! make %o1 point at end of src
	ld	[%o1-4],%g2	! load first limb
	sub	%g0,%o3,%o5	! negate shift count
	add	%o0,%g1,%o0	! make %o0 point at end of res
	add	%o2,-1,%o2
	andcc	%o2,4-1,%g4	! number of limbs in first loop
	srl	%g2,%o5,%g1	! compute function result
	be	L0		! if multiple of 4 limbs, skip first loop
	st	%g1,[%sp+80]

	sub	%o2,%g4,%o2	! adjust count for main loop

Loop0:	ld	[%o1-8],%g3
	add	%o0,-4,%o0
	add	%o1,-4,%o1
	addcc	%g4,-1,%g4
	sll	%g2,%o3,%o4
	srl	%g3,%o5,%g1
	mov	%g3,%g2
	or	%o4,%g1,%o4
	bne	Loop0
	 st	%o4,[%o0+0]

L0:	tst	%o2
	be	Lend
	 nop

Loop:	ld	[%o1-8],%g3
	add	%o0,-16,%o0
	addcc	%o2,-4,%o2
	sll	%g2,%o3,%o4
	srl	%g3,%o5,%g1

	ld	[%o1-12],%g2
	sll	%g3,%o3,%g4
	or	%o4,%g1,%o4
	st	%o4,[%o0+12]
	srl	%g2,%o5,%g1

	ld	[%o1-16],%g3
	sll	%g2,%o3,%o4
	or	%g4,%g1,%g4
	st	%g4,[%o0+8]
	srl	%g3,%o5,%g1

	ld	[%o1-20],%g2
	sll	%g3,%o3,%g4
	or	%o4,%g1,%o4
	st	%o4,[%o0+4]
	srl	%g2,%o5,%g1

	add	%o1,-16,%o1
	or	%g4,%g1,%g4
	bne	Loop
	 st	%g4,[%o0+0]

Lend:	sll	%g2,%o3,%g2
	st	%g2,[%o0-4]
	retl
	ld	[%sp+80],%o0