CryptoPkg/Library/BaseCryptLib/SysCall/Ia32/MathMultS64x64.c

   1 /** @file
   2   64-bit Math Worker Function.
   3   The 32-bit versions of C compiler generate calls to library routines
   4   to handle 64-bit math. These functions use non-standard calling conventions.
   5
   6 Copyright (c) 2009 - 2010, Intel Corporation. All rights reserved.<BR>
   7 This program and the accompanying materials
   8 are licensed and made available under the terms and conditions of the BSD License
   9 which accompanies this distribution.  The full text of the license may be found at
  10 http://opensource.org/licenses/bsd-license.php
  11
  12 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 #include <Library/BaseLib.h>
  18
  19 /*
  20  * Multiplies a 64-bit signed or unsigned value by a 64-bit signed or unsigned value
  21  * and returns a 64-bit result.
  22  */
  23 __declspec(naked) void __cdecl _allmul (void)
  24 {
  25   //
  26   // Wrapper Implementation over EDKII MultS64x64() routine
  27   //    INT64
  28   //    EFIAPI
  29   //    MultS64x64 (
  30   //      IN      INT64      Multiplicand,
  31   //      IN      INT64      Multiplier
  32   //      )
  33   //
  34   _asm {
  35     ; Original local stack when calling _allmul
  36     ;               -----------------
  37     ;               |               |
  38     ;               |---------------|
  39     ;               |               |
  40     ;               |--Multiplier --|
  41     ;               |               |
  42     ;               |---------------|
  43     ;               |               |
  44     ;               |--Multiplicand-|
  45     ;               |               |
  46     ;               |---------------|
  47     ;               |  ReturnAddr** |
  48     ;       ESP---->|---------------|
  49     ;
  50
  51     ;
  52     ; Set up the local stack for Multiplicand parameter
  53     ;
  54     mov  eax, [esp + 16]
  55     push eax
  56     mov  eax, [esp + 16]
  57     push eax
  58
  59     ;
  60     ; Set up the local stack for Multiplier parameter
  61     ;
  62     mov  eax, [esp + 16]
  63     push eax
  64     mov  eax, [esp + 16]
  65     push eax
  66
  67     ;
  68     ; Call native MulS64x64 of BaseLib
  69     ;
  70     call MultS64x64
  71
  72     ;
  73     ; Adjust stack
  74     ;
  75     add  esp, 16
  76
  77     ret  16
  78   }
  79 }