github.com/aergoio/aergo@v1.3.1/libtool/src/gmp-6.1.2/mpn/x86/lshift.asm (about)

     1  dnl  x86 mpn_lshift -- mpn left shift.
     2  
     3  dnl  Copyright 1992, 1994, 1996, 1999-2002 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  
    34  C     cycles/limb
    35  C P54	 7.5
    36  C P55	 7.0
    37  C P6	 2.5
    38  C K6	 4.5
    39  C K7	 5.0
    40  C P4	14.5
    41  
    42  
    43  C mp_limb_t mpn_lshift (mp_ptr dst, mp_srcptr src, mp_size_t size,
    44  C                       unsigned shift);
    45  
    46  defframe(PARAM_SHIFT,16)
    47  defframe(PARAM_SIZE, 12)
    48  defframe(PARAM_SRC,  8)
    49  defframe(PARAM_DST,  4)
    50  
    51  	TEXT
    52  	ALIGN(8)
    53  PROLOGUE(mpn_lshift)
    54  
    55  	pushl	%edi
    56  	pushl	%esi
    57  	pushl	%ebx
    58  deflit(`FRAME',12)
    59  
    60  	movl	PARAM_DST,%edi
    61  	movl	PARAM_SRC,%esi
    62  	movl	PARAM_SIZE,%edx
    63  	movl	PARAM_SHIFT,%ecx
    64  
    65  	subl	$4,%esi			C adjust src
    66  
    67  	movl	(%esi,%edx,4),%ebx	C read most significant limb
    68  	xorl	%eax,%eax
    69  	shldl(	%cl, %ebx, %eax)	C compute carry limb
    70  	decl	%edx
    71  	jz	L(end)
    72  	pushl	%eax			C push carry limb onto stack
    73  	testb	$1,%dl
    74  	jnz	L(1)			C enter loop in the middle
    75  	movl	%ebx,%eax
    76  
    77  	ALIGN(8)
    78  L(oop):	movl	(%esi,%edx,4),%ebx	C load next lower limb
    79  	shldl(	%cl, %ebx, %eax)	C compute result limb
    80  	movl	%eax,(%edi,%edx,4)	C store it
    81  	decl	%edx
    82  L(1):	movl	(%esi,%edx,4),%eax
    83  	shldl(	%cl, %eax, %ebx)
    84  	movl	%ebx,(%edi,%edx,4)
    85  	decl	%edx
    86  	jnz	L(oop)
    87  
    88  	shll	%cl,%eax		C compute least significant limb
    89  	movl	%eax,(%edi)		C store it
    90  
    91  	popl	%eax			C pop carry limb
    92  
    93  	popl	%ebx
    94  	popl	%esi
    95  	popl	%edi
    96  	ret
    97  
    98  L(end):	shll	%cl,%ebx		C compute least significant limb
    99  	movl	%ebx,(%edi)		C store it
   100  
   101  	popl	%ebx
   102  	popl	%esi
   103  	popl	%edi
   104  	ret
   105  
   106  EPILOGUE()