MdePkg/Library/BaseLib/Ia32/DivU64x64Remainder.s

   1 #------------------------------------------------------------------------------
   2 #
   3 # Copyright (c) 2006, Intel Corporation
   4 # All rights reserved. This program and the accompanying materials
   5 # are licensed and made available under the terms and conditions of the BSD License
   6 # which accompanies this distribution.  The full text of the license may be found at
   7 # http://opensource.org/licenses/bsd-license.php
   8 #
   9 # THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 # WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11 #
  12 # Module Name:
  13 #
  14 #   DivU64x64Remainder.asm
  15 #
  16 # Abstract:
  17 #
  18 #   Calculate the quotient of a 64-bit integer by a 64-bit integer and returns
  19 #   both the quotient and the remainder
  20 #
  21 #------------------------------------------------------------------------------
  22
  23
  24
  25
  26
  27 .extern _InternalMathDivRemU64x32
  28
  29 .global _InternalMathDivRemU64x64
  30 _InternalMathDivRemU64x64:
  31     movl    16(%esp),%ecx
  32     testl   %ecx,%ecx
  33     jnz     _DivRemU64x64
  34     movl    20(%esp),%ecx
  35     jecxz   L1
  36     and     $0,4(%ecx)
  37     movl    %ecx,16(%esp)
  38 L1:
  39     jmp     _InternalMathDivRemU64x32
  40
  41
  42 .global DivRemU64x64
  43 DivRemU64x64:
  44 # MISMATCH: "DivRemU64x64:    USES    ebx esi edi"
  45     push   %ebx
  46     push   %esi
  47     push   %edi
  48     mov     20(%esp), %edx
  49     mov     16(%esp), %eax
  50     movl    %edx,%edi
  51     movl    %eax,%esi
  52     mov     24(%esp), %ebx
  53 L2:
  54     shrl    %edx
  55     rcrl    $1,%eax
  56     shrdl   $1,%ecx,%ebx
  57     shrl    %ecx
  58     jnz     L2
  59     divl    %ebx
  60     movl    %eax,%ebx
  61     movl    28(%esp),%ecx
  62     mull    24(%esp)
  63     imull   %ebx,%ecx
  64     addl    %ecx,%edx
  65     mov     32(%esp), %ecx
  66     jc      TooLarge
  67     cmpl    %edx,%edi
  68     ja      Correct
  69     jb      TooLarge
  70     cmpl    %eax,%esi
  71     jae     Correct
  72 TooLarge:
  73     decl    %ebx
  74     jecxz   Return
  75     sub     24(%esp), %eax
  76     sbb     28(%esp), %edx
  77 Correct:
  78     jecxz   Return
  79     subl    %eax,%esi
  80     sbbl    %edx,%edi
  81     movl    %esi,(%ecx)
  82     movl    %edi,4(%ecx)
  83 Return:
  84     movl    %ebx,%eax
  85     xorl    %edx,%edx
  86     push   %edi
  87     push   %esi
  88     push   %ebx
  89     ret