github.com/aergoio/aergo@v1.3.1/libtool/src/gmp-6.1.2/mpn/powerpc64/p6/lshift.asm (about)

     1  dnl  PowerPC-64 mpn_lshift -- rp[] = up[] << cnt
     2  
     3  dnl  Copyright 2003, 2005, 2010, 2013 Free Software Foundation, Inc.
     4  
     5  dnl  This file is part of the GNU MP Library.
     6  dnl
     7  dnl  The GNU MP Library is free software; you can redistribute it and/or modify
     8  dnl  it under the terms of either:
     9  dnl
    10  dnl    * the GNU Lesser General Public License as published by the Free
    11  dnl      Software Foundation; either version 3 of the License, or (at your
    12  dnl      option) any later version.
    13  dnl
    14  dnl  or
    15  dnl
    16  dnl    * the GNU General Public License as published by the Free Software
    17  dnl      Foundation; either version 2 of the License, or (at your option) any
    18  dnl      later version.
    19  dnl
    20  dnl  or both in parallel, as here.
    21  dnl
    22  dnl  The GNU MP Library is distributed in the hope that it will be useful, but
    23  dnl  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
    24  dnl  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    25  dnl  for more details.
    26  dnl
    27  dnl  You should have received copies of the GNU General Public License and the
    28  dnl  GNU Lesser General Public License along with the GNU MP Library.  If not,
    29  dnl  see https://www.gnu.org/licenses/.
    30  
    31  include(`../config.m4')
    32  
    33  C		    cycles/limb
    34  C POWER3/PPC630		 ?
    35  C POWER4/PPC970		 ?
    36  C POWER5		 2.25
    37  C POWER6		 4
    38  
    39  C TODO
    40  C  * Micro-optimise header code
    41  C  * Perhaps do 4-way unrolling, for 2.5 c/l on POWER6.  The code is 4236
    42  C    bytes, 4-way code would become about 50% larger.
    43  
    44  C INPUT PARAMETERS
    45  define(`rp_param',  `r3')
    46  define(`up',  `r4')
    47  define(`n',   `r5')
    48  define(`cnt', `r6')
    49  
    50  define(`tnc',`r0')
    51  define(`retval',`r3')
    52  define(`rp',  `r7')
    53  
    54  ASM_START()
    55  PROLOGUE(mpn_lshift,toc)
    56  
    57  ifdef(`HAVE_ABI_mode32',`
    58  	rldicl	n, n, 0,32		C FIXME: avoid this zero extend
    59  ')
    60  	mflr	r12
    61  	sldi	r8, n, 3
    62  	sldi	r10, cnt, 6		C multiply cnt by size of a SHIFT block
    63  	LEAL(	r11, L(e1))		C address of L(e1) label in SHIFT(1)
    64  	add	up, up, r8		C make up point at end of up[]
    65  	add	r11, r11, r10		C address of L(oN) for N = cnt
    66  	srdi	r10, n, 1
    67  	add	rp, rp_param, r8	C make rp point at end of rp[]
    68  	subfic	tnc, cnt, 64
    69  	rlwinm.	r8, n, 0,31,31		C extract bit 0
    70  	mtctr	r10
    71  	beq	L(evn)
    72  
    73  L(odd):	ld	r9, -8(up)
    74  	cmpdi	cr0, n, 1		C n = 1?
    75  	beq	L(1)
    76  	ld	r8, -16(up)
    77  	addi	r11, r11, -84		C L(o1) - L(e1) - 64
    78  	mtlr	r11
    79  	srd	r3, r9, tnc		C retval
    80  	addi	up, up, 8
    81  	addi	rp, rp, -8
    82  	blr				C branch to L(oN)
    83  
    84  L(evn):	ld	r8, -8(up)
    85  	ld	r9, -16(up)
    86  	addi	r11, r11, -64
    87  	mtlr	r11
    88  	srd	r3, r8, tnc		C retval
    89  	blr				C branch to L(eN)
    90  
    91  L(1):	srd	r3, r9, tnc		C retval
    92  	sld	r8, r9, cnt
    93  	std	r8, -8(rp)
    94  	mtlr	r12
    95  ifdef(`HAVE_ABI_mode32',
    96  `	mr	r4, r3
    97  	srdi	r3, r3, 32
    98  ')
    99  	blr
   100  
   101  
   102  define(SHIFT,`
   103  L(lo$1):ld	r8, -24(up)
   104  	std	r11, -8(rp)
   105  	addi	rp, rp, -16
   106  L(o$1):	srdi	r10, r8, eval(64-$1)
   107  	rldimi	r10, r9, $1, 0
   108  	ld	r9, -32(up)
   109  	addi	up, up, -16
   110  	std	r10, 0(rp)
   111  L(e$1):	srdi	r11, r9, eval(64-$1)
   112  	rldimi	r11, r8, $1, 0
   113  	bdnz	L(lo$1)
   114  	std	r11, -8(rp)
   115  	sldi	r10, r9, $1
   116  	b	L(com)
   117  	nop
   118  	nop
   119  ')
   120  
   121  	ALIGN(64)
   122  forloop(`i',1,63,`SHIFT(i)')
   123  
   124  L(com):	std	r10, -16(rp)
   125  	mtlr	r12
   126  ifdef(`HAVE_ABI_mode32',
   127  `	mr	r4, r3
   128  	srdi	r3, r3, 32
   129  ')
   130  	blr
   131  EPILOGUE()
   132  ASM_END()