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

     1  dnl  Intel Pentium mpn_copyd -- copy limb vector, decrementing.
     2  
     3  dnl  Copyright 1996, 2001, 2002, 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  
    34  C P5: 1.25 cycles/limb
    35  
    36  
    37  C void mpn_copyd (mp_ptr dst, mp_srcptr src, mp_size_t size);
    38  C
    39  C See comments in copyi.asm.
    40  
    41  defframe(PARAM_SIZE,12)
    42  defframe(PARAM_SRC, 8)
    43  defframe(PARAM_DST, 4)
    44  
    45  	TEXT
    46  	ALIGN(8)
    47  PROLOGUE(mpn_copyd)
    48  deflit(`FRAME',0)
    49  
    50  	movl	PARAM_SRC, %eax
    51  	movl	PARAM_SIZE, %ecx
    52  
    53  	pushl	%esi	FRAME_pushl()
    54  	pushl	%edi	FRAME_pushl()
    55  
    56  	leal	-4(%eax,%ecx,4), %eax		C &src[size-1]
    57  	movl	PARAM_DST, %edx
    58  
    59  	subl	$7, %ecx			C size-7
    60  	jle	L(end)
    61  
    62  	movl	28-4(%edx,%ecx,4), %esi		C prefetch cache, dst[size-1]
    63  	nop
    64  
    65  L(top):
    66  	C eax	src, decrementing
    67  	C ebx
    68  	C ecx	counter, limbs
    69  	C edx	dst
    70  	C esi	scratch
    71  	C edi	scratch
    72  	C ebp
    73  
    74  	movl	28-32(%edx,%ecx,4), %esi	C prefetch dst cache line
    75  	subl	$8, %ecx
    76  
    77  	movl	(%eax), %esi			C read words pairwise
    78  	movl	-4(%eax), %edi
    79  	movl	%esi, 56(%edx,%ecx,4)		C store words pairwise
    80  	movl	%edi, 52(%edx,%ecx,4)
    81  
    82  	movl	-8(%eax), %esi
    83  	movl	-12(%eax), %edi
    84  	movl	%esi, 48(%edx,%ecx,4)
    85  	movl	%edi, 44(%edx,%ecx,4)
    86  
    87  	movl	-16(%eax), %esi
    88  	movl	-20(%eax), %edi
    89  	movl	%esi, 40(%edx,%ecx,4)
    90  	movl	%edi, 36(%edx,%ecx,4)
    91  
    92  	movl	-24(%eax), %esi
    93  	movl	-28(%eax), %edi
    94  	movl	%esi, 32(%edx,%ecx,4)
    95  	movl	%edi, 28(%edx,%ecx,4)
    96  
    97  	leal	-32(%eax), %eax
    98  	jg	L(top)
    99  
   100  
   101  L(end):
   102  	C ecx	-7 to 0, representing respectively 0 to 7 limbs remaining
   103  	C eax	src end
   104  	C edx	dst, next location to store
   105  
   106  	addl	$4, %ecx
   107  	jle	L(no4)
   108  
   109  	movl	(%eax), %esi
   110  	movl	-4(%eax), %edi
   111  	movl	%esi, 8(%edx,%ecx,4)
   112  	movl	%edi, 4(%edx,%ecx,4)
   113  
   114  	movl	-8(%eax), %esi
   115  	movl	-12(%eax), %edi
   116  	movl	%esi, (%edx,%ecx,4)
   117  	movl	%edi, -4(%edx,%ecx,4)
   118  
   119  	subl	$16, %eax
   120  	subl	$4, %ecx
   121  L(no4):
   122  
   123  	addl	$2, %ecx
   124  	jle	L(no2)
   125  
   126  	movl	(%eax), %esi
   127  	movl	-4(%eax), %edi
   128  	movl	%esi, (%edx,%ecx,4)
   129  	movl	%edi, -4(%edx,%ecx,4)
   130  
   131  	subl	$8, %eax
   132  	subl	$2, %ecx
   133  L(no2):
   134  
   135  	jnz	L(done)
   136  
   137  	movl	(%eax), %ecx
   138  	movl	%ecx, (%edx)	C risk of cache bank clash here
   139  
   140  L(done):
   141  	popl	%edi
   142  	popl	%esi
   143  
   144  	ret
   145  
   146  EPILOGUE()