dnl  SPARC v9 mpn_rshift

dnl  Copyright 1996, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.

dnl  This file is part of the GNU MP Library.

dnl  The GNU MP Library is free software; you can redistribute it and/or modify
dnl  it under the terms of the GNU Lesser General Public License as published
dnl  by the Free Software Foundation; either version 3 of the License, or (at
dnl  your option) any later version.

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 Lesser General Public
dnl  License for more details.

dnl  You should have received a copy of the GNU Lesser General Public License
dnl  along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.


include(`../config.m4')

C		   cycles/limb
C UltraSPARC 1&2:     2
C UltraSPARC 3:	      3.25

C INPUT PARAMETERS
define(`rp',`%i0')
define(`up',`%i1')
define(`n',`%i2')
define(`cnt',`%i3')

define(`u0',`%l0')
define(`u1',`%l2')
define(`u2',`%l4')
define(`u3',`%l6')

define(`tnc',`%i4')

define(`fanop',`fitod %f0,%f2')		dnl  A quasi nop running in the FA pipe
define(`fmnop',`fmuld %f0,%f0,%f4')	dnl  A quasi nop running in the FM pipe

ASM_START()
	REGISTER(%g2,#scratch)
	REGISTER(%g3,#scratch)
PROLOGUE(mpn_rshift)
	save	%sp,-160,%sp

	sub	%g0,cnt,tnc		C negate shift count
	ldx	[up],u3			C load first limb
	subcc	n,5,n
	sllx	u3,tnc,%i5		C compute function result
	srlx	u3,cnt,%g3
	bl,pn	%icc,.Lend1234
	fanop

	subcc	n,4,n
	ldx	[up+8],u0
	ldx	[up+16],u1
	add	up,32,up
	ldx	[up-8],u2
	ldx	[up+0],u3
	sllx	u0,tnc,%g2

	bl,pn	%icc,.Lend5678
	fanop

	b,a	.Loop
	.align	16
.Loop:
	srlx	u0,cnt,%g1
	or	%g3,%g2,%g3
	ldx	[up+8],u0
	fanop
C --
	sllx	u1,tnc,%g2
	subcc	n,4,n
	stx	%g3,[rp+0]
	fanop
C --
	srlx	u1,cnt,%g3
	or	%g1,%g2,%g1
	ldx	[up+16],u1
	fanop
C --
	sllx	u2,tnc,%g2
	stx	%g1,[rp+8]
	add	up,32,up
	fanop
C --
	srlx	u2,cnt,%g1
	or	%g3,%g2,%g3
	ldx	[up-8],u2
	fanop
C --
	sllx	u3,tnc,%g2
	stx	%g3,[rp+16]
	add	rp,32,rp
	fanop
C --
	srlx	u3,cnt,%g3
	or	%g1,%g2,%g1
	ldx	[up+0],u3
	fanop
C --
	sllx	u0,tnc,%g2
	stx	%g1,[rp-8]
	bge,pt	%icc,.Loop
	fanop
C --
.Lend5678:
	srlx	u0,cnt,%g1
	or	%g3,%g2,%g3
	sllx	u1,tnc,%g2
	stx	%g3,[rp+0]
	srlx	u1,cnt,%g3
	or	%g1,%g2,%g1
	sllx	u2,tnc,%g2
	stx	%g1,[rp+8]
	srlx	u2,cnt,%g1
	or	%g3,%g2,%g3
	sllx	u3,tnc,%g2
	stx	%g3,[rp+16]
	add	rp,32,rp
	srlx	u3,cnt,%g3		C carry...
	or	%g1,%g2,%g1
	stx	%g1,[rp-8]

.Lend1234:
	addcc	n,4,n
	bz,pn	%icc,.Lret
	fanop
.Loop0:
	add	rp,8,rp
	subcc	n,1,n
	ldx	[up+8],u3
	add	up,8,up
	sllx	u3,tnc,%g2
	or	%g3,%g2,%g3
	stx	%g3,[rp-8]
	srlx	u3,cnt,%g3
	bnz,pt	%icc,.Loop0
	fanop
.Lret:
	stx	%g3,[rp+0]
	mov	%i5,%i0
	ret
	restore
EPILOGUE(mpn_rshift)