CryptoPkg/Library/BaseCryptLib/SysCall/Ia32/MathDivU64x64.S

   1 #------------------------------------------------------------------------------
   2 #
   3 # Copyright (c) 2009 - 2010, Intel Corporation. All rights reserved.<BR>
   4 # 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 #   MathDivU64x64.S
  15 #
  16 # Abstract:
  17 #
  18 #   64-bit Math Worker Function.
  19 #   Divides a 64-bit unsigned value with a 64-bit unsigned value and returns
  20 #   a 64-bit unsigned result.
  21 #
  22 #------------------------------------------------------------------------------
  23
  24     .686:
  25     .code:
  26
  27 ASM_GLOBAL ASM_PFX(__udivdi3), ASM_PFX(DivU64x64Remainder)
  28
  29 #------------------------------------------------------------------------------
  30 #
  31 # void __cdecl __udivdi3 (void)
  32 #
  33 #------------------------------------------------------------------------------
  34 ASM_PFX(__udivdi3):
  35     # Original local stack when calling __udivdi3
  36     #               -----------------
  37     #               |               |
  38     #               |---------------|
  39     #               |               |
  40     #               |--  Divisor  --|
  41     #               |               |
  42     #               |---------------|
  43     #               |               |
  44     #               |--  Dividend --|
  45     #               |               |
  46     #               |---------------|
  47     #               |  ReturnAddr** |
  48     #       ESP---->|---------------|
  49     #
  50
  51     #
  52     # Set up the local stack for NULL Reminder pointer
  53     #
  54     xorl    %eax, %eax
  55     push    %eax
  56
  57     #
  58     # Set up the local stack for Divisor parameter
  59     #
  60     movl    20(%esp), %eax
  61     push    %eax
  62     movl    20(%esp), %eax
  63     push    %eax
  64
  65     #
  66     # Set up the local stack for Dividend parameter
  67     #
  68     movl    20(%esp), %eax
  69     push    %eax
  70     movl    20(%esp), %eax
  71     push    %eax
  72
  73     #
  74     # Call native DivU64x64Remainder of BaseLib
  75     #
  76     jmp     ASM_PFX(DivU64x64Remainder)
  77
  78     #
  79     # Adjust stack
  80     #
  81     addl    $20, %esp
  82
  83     ret     $16