dnl  S/390-64 mpn_mul_basecase.

dnl  Copyright 2011 Free Software Foundation, Inc.

dnl  This file is part of the GNU MP Library.

dnl

dnl  The GNU MP Library is free software; you can redistribute it and/or modify

dnl  it under the terms of either:

dnl

dnl    * the GNU Lesser General Public License as published by the Free

dnl      Software Foundation; either version 3 of the License, or (at your

dnl      option) any later version.

dnl

dnl  or

dnl

dnl    * the GNU General Public License as published by the Free Software

dnl      Foundation; either version 2 of the License, or (at your option) any

dnl      later version.

dnl

dnl  or both in parallel, as here.

dnl

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 General Public License

dnl  for more details.

dnl

dnl  You should have received copies of the GNU General Public License and the

dnl  GNU Lesser General Public License along with the GNU MP Library.  If not,

dnl  see https://www.gnu.org/licenses/.

include(`../config.m4')

C            cycles/limb

C z900		 ?

C z990		23

C z9		 ?

C z10		28

C z196		 ?

C TODO

C  * Perhaps add special case for un <= 2.

C  * Replace loops by faster code.  The mul_1 and addmul_1 loops could be sped

C    up by about 10%.

C INPUT PARAMETERS

define(`rp',	`%r2')

define(`up',	`%r3')

define(`un',	`%r4')

define(`vp',	`%r5')

define(`vn',	`%r6')

define(`zero',	`%r8')

ASM_START()

PROLOGUE(mpn_mul_basecase)

	cghi	un, 2

	jhe	L(ge2)

C un = vn = 1

	lg	%r1, 0(vp)

	mlg	%r0, 0(up)

	stg	%r1, 0(rp)

	stg	%r0, 8(rp)

	br	%r14

L(ge2):	C jne	L(gen)

L(gen):

C mul_1 =======================================================================

	stmg	%r6, %r12, 48(%r15)

	lghi	zero, 0

	aghi	un, -1

	lg	%r7, 0(vp)

	lg	%r11, 0(up)

	lghi	%r12, 8			C init index register

	mlgr	%r10, %r7

	lgr	%r9, un

	stg	%r11, 0(rp)

	cr	%r15, %r15		C clear carry flag

L(tm):	lg	%r1, 0(%r12,up)

	mlgr	%r0, %r7

	alcgr	%r1, %r10

	lgr	%r10, %r0		C copy high part to carry limb

	stg	%r1, 0(%r12,rp)

	la	%r12, 8(%r12)

	brctg	%r9, L(tm)

	alcgr	%r0, zero

	stg	%r0, 0(%r12,rp)

C addmul_1 loop ===============================================================

	aghi	vn, -1

	je	L(outer_end)

L(outer_loop):

	la	rp, 8(rp)		C rp += 1

	la	vp, 8(vp)		C up += 1

	lg	%r7, 0(vp)

	lg	%r11, 0(up)

	lghi	%r12, 8			C init index register

	mlgr	%r10, %r7

	lgr	%r9, un

	alg	%r11, 0(rp)

	stg	%r11, 0(rp)

L(tam):	lg	%r1, 0(%r12,up)

	lg	%r11, 0(%r12,rp)

	mlgr	%r0, %r7

	alcgr	%r1, %r11

	alcgr	%r0, zero

	algr	%r1, %r10

	lgr	%r10, %r0

	stg	%r1, 0(%r12,rp)

	la	%r12, 8(%r12)

	brctg	%r9, L(tam)

	alcgr	%r0, zero

	stg	%r0, 0(%r12,rp)

	brctg	vn, L(outer_loop)

L(outer_end):

	lmg	%r6, %r12, 48(%r15)

	br	%r14

EPILOGUE()