source/libs/gmp/gmp-src/mpn/x86/lshift.asm

   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()