github.com/aergoio/aergo@v1.3.1/libtool/src/gmp-6.1.2/mpn/powerpc64/mode64/mode1o.asm (about)

     1  dnl  PowerPC-64 mpn_modexact_1_odd -- mpn by limb exact remainder.
     2  
     3  dnl  Copyright 2006 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        13-19
    35  C POWER4/PPC970         16
    36  C POWER5                16
    37  C POWER6                 ?
    38  C POWER7                12
    39  
    40  C TODO
    41  C  * Check if n=1 code is really an improvement.  It probably isn't.
    42  C  * Make more similar to dive_1.asm.
    43  
    44  C INPUT PARAMETERS
    45  define(`up', `r3')
    46  define(`n',  `r4')
    47  define(`d',  `r5')
    48  define(`cy', `r6')
    49  
    50  
    51  ASM_START()
    52  
    53  EXTERN(binvert_limb_table)
    54  
    55  PROLOGUE(mpn_modexact_1c_odd,toc)
    56  	addic.	n, n, -1		C set carry as side effect
    57  	ld	r8, 0(up)
    58  	bne	cr0, L(2)
    59  	cmpld	cr7, r6, r8
    60  	bge	cr7, L(4)
    61  	subf	r8, r6, r8
    62  	divdu	r3, r8, d
    63  	mulld	r3, r3, d
    64  	subf.	r3, r3, r8
    65  	beqlr	cr0
    66  	subf	r3, r3, d
    67  	blr
    68  
    69  L(4):	subf	r3, r8, r6
    70  	divdu	r8, r3, d
    71  	mulld	r8, r8, d
    72  	subf	r3, r8, r3
    73  	blr
    74  
    75  L(2):	LEA(	r7, binvert_limb_table)
    76  	rldicl	r9, d, 63, 57
    77  	mtctr	n
    78  	lbzx	r0, r7, r9
    79  	mulld	r7, r0, r0
    80  	sldi	r0, r0, 1
    81  	mulld	r7, d, r7
    82  	subf	r0, r7, r0
    83  	mulld	r9, r0, r0
    84  	sldi	r0, r0, 1
    85  	mulld	r9, d, r9
    86  	subf	r0, r9, r0
    87  	mulld	r7, r0, r0
    88  	sldi	r0, r0, 1
    89  	mulld	r7, d, r7
    90  	subf	r9, r7, r0
    91  
    92  	ALIGN(16)
    93  L(loop):
    94  	subfe	r0, r6, r8
    95  	ld	r8, 8(up)
    96  	addi	up, up, 8
    97  	mulld	r0, r9, r0
    98  	mulhdu	r6, r0, d
    99  	bdnz	L(loop)
   100  
   101  	cmpld	cr7, d, r8
   102  	blt	cr7, L(10)
   103  
   104  	subfe	r0, r0, r0
   105  	subf	r6, r0, r6
   106  	cmpld	cr7, r6, r8
   107  	subf	r3, r8, r6
   108  	bgelr	cr7
   109  	add	r3, d, r3
   110  	blr
   111  
   112  L(10):	subfe	r0, r6, r8
   113  	mulld	r0, r9, r0
   114  	mulhdu	r3, r0, d
   115  	blr
   116  EPILOGUE()
   117  ASM_END()