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      1 dnl  ARM mpn_lshiftc.
      2 
      3 dnl  Contributed to the GNU project by Torbjrn Granlund.
      4 
      5 dnl  Copyright 2012 Free Software Foundation, Inc.
      6 
      7 dnl  This file is part of the GNU MP Library.
      8 dnl
      9 dnl  The GNU MP Library is free software; you can redistribute it and/or modify
     10 dnl  it under the terms of either:
     11 dnl
     12 dnl    * the GNU Lesser General Public License as published by the Free
     13 dnl      Software Foundation; either version 3 of the License, or (at your
     14 dnl      option) any later version.
     15 dnl
     16 dnl  or
     17 dnl
     18 dnl    * the GNU General Public License as published by the Free Software
     19 dnl      Foundation; either version 2 of the License, or (at your option) any
     20 dnl      later version.
     21 dnl
     22 dnl  or both in parallel, as here.
     23 dnl
     24 dnl  The GNU MP Library is distributed in the hope that it will be useful, but
     25 dnl  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
     26 dnl  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
     27 dnl  for more details.
     28 dnl
     29 dnl  You should have received copies of the GNU General Public License and the
     30 dnl  GNU Lesser General Public License along with the GNU MP Library.  If not,
     31 dnl  see https://www.gnu.org/licenses/.
     32 
     33 include(`../config.m4')
     34 
     35 C	     cycles/limb
     36 C StrongARM	 ?
     37 C XScale	 ?
     38 C Cortex-A7	 ?
     39 C Cortex-A8	 ?
     40 C Cortex-A9	 4.0
     41 C Cortex-A15	 ?
     42 
     43 define(`rp',  `r0')
     44 define(`up',  `r1')
     45 define(`n',   `r2')
     46 define(`cnt', `r3')
     47 define(`tnc', `r12')
     48 
     49 ASM_START()
     50 PROLOGUE(mpn_lshiftc)
     51 	add	up, up, n, lsl #2
     52 	push	{r4, r6, r7, r8}
     53 	ldr	r4, [up, #-4]!
     54 	add	rp, rp, n, lsl #2
     55 	rsb	tnc, cnt, #32
     56 	mvn	r6, r4
     57 
     58 	mov	r7, r6, lsl cnt
     59 	tst	n, #1
     60 	beq	L(evn)			C n even
     61 
     62 L(odd):	subs	n, n, #2
     63 	bcc	L(1)			C n = 1
     64 	ldr	r8, [up, #-4]!
     65 	mvn	r8, r8
     66 	b	L(mid)
     67 
     68 L(evn):	ldr	r6, [up, #-4]!
     69 	mvn	r6, r6
     70 	subs	n, n, #2
     71 	beq	L(end)
     72 
     73 L(top):	ldr	r8, [up, #-4]!
     74 	orr	r7, r7, r6, lsr tnc
     75 	str	r7, [rp, #-4]!
     76 	mvn	r8, r8
     77 	mov	r7, r6, lsl cnt
     78 L(mid):	ldr	r6, [up, #-4]!
     79 	orr	r7, r7, r8, lsr tnc
     80 	str	r7, [rp, #-4]!
     81 	mvn	r6, r6
     82 	mov	r7, r8, lsl cnt
     83 	subs	n, n, #2
     84 	bgt	L(top)
     85 
     86 L(end):	orr	r7, r7, r6, lsr tnc
     87 	str	r7, [rp, #-4]!
     88 	mov	r7, r6, lsl cnt
     89 L(1):	mvn	r6, #0
     90 	orr	r7, r7, r6, lsr tnc
     91 	str	r7, [rp, #-4]
     92 	mov	r0, r4, lsr tnc
     93 	pop	{r4, r6, r7, r8}
     94 	return	r14
     95 EPILOGUE()
     96