dnl  PowerPC-64 mpn_lshift -- rp[] = up[] << cnt

dnl  Copyright 2003, 2005 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 POWER3/PPC630:     1.5
C POWER4/PPC970:     3.0

C INPUT PARAMETERS
define(`rp',`r3')
define(`up',`r4')
define(`n',`r5')
define(`cnt',`r6')

define(`tnc',`r5')
define(`v0',`r0')
define(`v1',`r7')
define(`u0',`r8')
define(`u1',`r9')
define(`h0',`r10')
define(`h1',`r11')


ASM_START()
PROLOGUE(mpn_lshift)
ifdef(`HAVE_ABI_mode32',
`	rldicl	r7, r5, 0, 32	C zero extend n
	mtctr	r7',		C copy n to count register
`	mtctr	n')		C copy n to count register

ifdef(`HAVE_ABI_mode32',
`	rldic	r0, n, 3, 32',	C byte count corresponding to n
`	rldicr	r0, n, 3, 60')	C byte count corresponding to n

	add	rp, rp, r0	C rp = rp + n
	add	up, up, r0	C up = up + n
	addi	rp, rp, 8	C rp now points 16 beyond end
	addi	up, up, -8	C up now points to last limb
	subfic	tnc, cnt, 64	C reverse shift count

	ld	u0, 0(up)
	sld	h0, u0, cnt
	srd	r12, u0, tnc	C return value
	bdz	L(1)		C jump for n = 1

	ld	u1, -8(up)
	bdz	L(2)		C jump for n = 2

	ldu	u0, -16(up)
	bdz	L(end)		C jump for n = 3

L(oop):	srd	v1, u1, tnc
	sld	h1, u1, cnt
	ld	u1, -8(up)
	or	h0, v1, h0
	stdu	h0, -16(rp)

	bdz	L(exit)

	srd	v0, u0, tnc
	sld	h0, u0, cnt
	ldu	u0, -16(up)
	or	h1, v0, h1
	std	h1, -8(rp)

	bdnz	L(oop)

L(end):	srd	v1, u1, tnc
	sld	h1, u1, cnt
	or	h0, v1, h0
	stdu	h0, -16(rp)
	srd	v0, u0, tnc
	sld	h0, u0, cnt
	or	h1, v0, h1
	std	h1, -8(rp)
L(1):	std	h0, -16(rp)
ifdef(`HAVE_ABI_mode32',
`	srdi	r3, r12, 32
	mr	r4, r12
',`	mr	r3, r12
')
	blr

L(exit):	srd	v0, u0, tnc
	sld	h0, u0, cnt
	or	h1, v0, h1
	std	h1, -8(rp)
L(2):	srd	v1, u1, tnc
	sld	h1, u1, cnt
	or	h0, v1, h0
	stdu	h0, -16(rp)
	std	h1, -8(rp)
ifdef(`HAVE_ABI_mode32',
`	srdi	r3, r12, 32
	mr	r4, r12
',`	mr	r3, r12
')
	blr
EPILOGUE()


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