github.com/aergoio/aergo@v1.3.1/libtool/src/gmp-6.1.2/mpn/x86_64/atom/lshiftc.asm (about)

     1  dnl  AMD64 mpn_lshiftc -- mpn left shift with complement, optimised for Atom.
     2  
     3  dnl  Contributed to the GNU project by Torbjorn Granlund.
     4  
     5  dnl  Copyright 2011, 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 AMD K8,K9	 ?
    37  C AMD K10	 ?
    38  C Intel P4	 ?
    39  C Intel core2	 ?
    40  C Intel NHM	 ?
    41  C Intel SBR	 ?
    42  C Intel atom	 5
    43  C VIA nano	 ?
    44  
    45  C TODO
    46  C  * Consider using 4-way unrolling.  We reach 4.5 c/l, but the code is 2.5
    47  C    times larger.
    48  
    49  C INPUT PARAMETERS
    50  define(`rp',	`%rdi')
    51  define(`up',	`%rsi')
    52  define(`n',	`%rdx')
    53  define(`cnt',	`%rcx')
    54  
    55  ABI_SUPPORT(DOS64)
    56  ABI_SUPPORT(STD64)
    57  
    58  ASM_START()
    59  	TEXT
    60  	ALIGN(16)
    61  PROLOGUE(mpn_lshiftc)
    62  	FUNC_ENTRY(4)
    63  	lea	-8(up,n,8), up
    64  	lea	-8(rp,n,8), rp
    65  	shr	R32(n)
    66  	mov	(up), %rax
    67  	jnc	L(evn)
    68  
    69  	mov	%rax, %r11
    70  	shl	R8(%rcx), %r11
    71  	neg	R8(%rcx)
    72  	shr	R8(%rcx), %rax
    73  	test	n, n
    74  	jnz	L(gt1)
    75  	not	%r11
    76  	mov	%r11, (rp)
    77  	FUNC_EXIT()
    78  	ret
    79  
    80  L(gt1):	mov	-8(up), %r8
    81  	mov	%r8, %r10
    82  	shr	R8(%rcx), %r8
    83  	jmp	L(lo1)
    84  
    85  L(evn):	mov	%rax, %r10
    86  	neg	R8(%rcx)
    87  	shr	R8(%rcx), %rax
    88  	mov	-8(up), %r9
    89  	mov	%r9, %r11
    90  	shr	R8(%rcx), %r9
    91  	neg	R8(%rcx)
    92  	lea	8(rp), rp
    93  	lea	-8(up), up
    94  	jmp	L(lo0)
    95  
    96  C	ALIGN(16)
    97  L(top):	shl	R8(%rcx), %r10
    98  	or	%r10, %r9
    99  	shl	R8(%rcx), %r11
   100  	not	%r9
   101  	neg	R8(%rcx)
   102  	mov	-8(up), %r8
   103  	lea	-16(rp), rp
   104  	mov	%r8, %r10
   105  	shr	R8(%rcx), %r8
   106  	mov	%r9, 8(rp)
   107  L(lo1):	or	%r11, %r8
   108  	mov	-16(up), %r9
   109  	mov	%r9, %r11
   110  	shr	R8(%rcx), %r9
   111  	lea	-16(up), up
   112  	neg	R8(%rcx)
   113  	not	%r8
   114  	mov	%r8, (rp)
   115  L(lo0):	dec	n
   116  	jg	L(top)
   117  
   118  L(end):	shl	R8(%rcx), %r10
   119  	or	%r10, %r9
   120  	not	%r9
   121  	shl	R8(%rcx), %r11
   122  	not	%r11
   123  	mov	%r9, -8(rp)
   124  	mov	%r11, -16(rp)
   125  	FUNC_EXIT()
   126  	ret
   127  EPILOGUE()