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

     1  dnl  X86 mpn_cnd_sub_n optimised for Intel Atom.
     2  
     3  dnl  Copyright 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 P5				 ?
    35  C P6 model 0-8,10-12		 ?
    36  C P6 model 9   (Banias)		 ?
    37  C P6 model 13  (Dothan)		 ?
    38  C P4 model 0-1 (Willamette)	 ?
    39  C P4 model 2   (Northwood)	 ?
    40  C P4 model 3-4 (Prescott)	 ?
    41  C Intel atom			 5.67
    42  C AMD K6			 ?
    43  C AMD K7			 ?
    44  C AMD K8			 ?
    45  
    46  
    47  define(`rp',  `%edi')
    48  define(`up',  `%esi')
    49  define(`vp',  `%ebp')
    50  define(`n',   `%ecx')
    51  define(`cnd', `20(%esp)')
    52  
    53  ASM_START()
    54  	TEXT
    55  	ALIGN(16)
    56  PROLOGUE(mpn_cnd_sub_n)
    57  	push	%edi
    58  	push	%esi
    59  	push	%ebx
    60  	push	%ebp
    61  
    62  	mov	cnd, %eax		C make cnd into a mask (1)
    63  	mov	24(%esp), rp
    64  	neg	%eax			C make cnd into a mask (1)
    65  	mov	28(%esp), up
    66  	sbb	%eax, %eax		C make cnd into a mask (1)
    67  	mov	32(%esp), vp
    68  	mov	%eax, cnd		C make cnd into a mask (1)
    69  	mov	36(%esp), n
    70  
    71  	xor	%edx, %edx
    72  
    73  	inc	n
    74  	shr	n
    75  	jnc	L(ent)
    76  
    77  	mov	0(vp), %eax
    78  	and	cnd, %eax
    79  	lea	4(vp), vp
    80  	mov	0(up), %edx
    81  	sub	%eax, %edx
    82  	lea	4(rp), rp
    83  	lea	4(up), up
    84  	mov	%edx, -4(rp)
    85  	sbb	%edx, %edx		C save cy
    86  
    87  L(ent):	mov	0(vp), %ebx
    88  	and	cnd, %ebx
    89  	add	%edx, %edx		C restore cy
    90  	mov	0(up), %edx
    91  	dec	n
    92  	je	L(end)
    93  
    94  L(top):	sbb	%ebx, %edx
    95  	mov	4(vp), %eax
    96  	mov	%edx, 0(rp)
    97  	sbb	%edx, %edx		C save cy
    98  	mov	8(vp), %ebx
    99  	lea	8(up), up
   100  	and	cnd, %ebx
   101  	and	cnd, %eax
   102  	add	%edx, %edx		C restore cy
   103  	mov	-4(up), %edx
   104  	lea	8(rp), rp
   105  	sbb	%eax, %edx
   106  	mov	%edx, -4(rp)
   107  	dec	n
   108  	mov	0(up), %edx
   109  	lea	8(vp), vp
   110  	jne	L(top)
   111  
   112  L(end):	sbb	%ebx, %edx
   113  	mov	%edx, 0(rp)
   114  
   115  	mov	$0, %eax
   116  	adc	%eax, %eax
   117  
   118  	pop	%ebp
   119  	pop	%ebx
   120  	pop	%esi
   121  	pop	%edi
   122  	ret
   123  EPILOGUE()
   124  ASM_END()