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/** @file
64-bit Math Worker Function.
The 32-bit versions of C compiler generate calls to library routines
to handle 64-bit math. These functions use non-standard calling conventions.

Copyright (c) 2009 - 2011, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials are licensed and made available
under the terms and conditions of the BSD License which accompanies this
distribution.  The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php.

THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include <uefi.h>
#include <Library/BaseLib.h>

#if defined(_M_IX86)
//////////////////////////////////////////////////////////////////////////
// _allmul
//////////////////////////////////////////////////////////////////////////
/*
 * Multiplies a 64-bit signed or unsigned value by a 64-bit signed or unsigned value
 * and returns a 64-bit result.
 */
__declspec(naked) void __cdecl _allmul (void)
{
  //
  // Wrapper Implementation over EDKII MultS64x64() routine
  //    INT64
  //    EFIAPI
  //    MultS64x64 (
  //      IN      INT64      Multiplicand,
  //      IN      INT64      Multiplier
  //      )
  //
  _asm {
    ; Original local stack when calling _allmul
    ;               -----------------
    ;               |               |
    ;               |---------------|
    ;               |               |
    ;               |--Multiplier --|
    ;               |               |
    ;               |---------------|
    ;               |               |
    ;               |--Multiplicand-|
    ;               |               |
    ;               |---------------|
    ;               |  ReturnAddr** |
    ;       ESP---->|---------------|
    ;

    ;
    ; Set up the local stack for Multiplicand parameter
    ;
    mov  eax, [esp + 16]
    push eax
    mov  eax, [esp + 16]
    push eax

    ;
    ; Set up the local stack for Multiplier parameter
    ;
    mov  eax, [esp + 16]
    push eax
    mov  eax, [esp + 16]
    push eax

    ;
    ; Call native MulS64x64 of BaseLib
    ;
    call MultS64x64

    ;
    ; Adjust stack
    ;
    add  esp, 16

    ret  16
  }
} 

//////////////////////////////////////////////////////////////////////////
// _alldiv
//////////////////////////////////////////////////////////////////////////
/*
 * Divides a 64-bit signed value with a 64-bit signed value and returns
 * a 64-bit signed result.
 */
__declspec(naked) void __cdecl _alldiv (void)
{
  //
  // Wrapper Implementation over EDKII DivS64x64Remainder() routine
  //    INT64
  //    EFIAPI
  //    DivS64x64Remainder (
  //      IN      UINT64     Dividend,
  //      IN      UINT64     Divisor,
  //      OUT     UINT64     *Remainder  OPTIONAL
  //      )
  //
  _asm {

    ;Entry:
    ;       Arguments are passed on the stack:
    ;               1st pushed: divisor (QWORD)
    ;               2nd pushed: dividend (QWORD)
    ;
    ;Exit:
    ;       EDX:EAX contains the quotient (dividend/divisor)
    ;       NOTE: this routine removes the parameters from the stack.
    ;
    ; Original local stack when calling _alldiv
    ;               -----------------
    ;               |               |
    ;               |---------------|
    ;               |               |
    ;               |--  Divisor  --|
    ;               |               |
    ;               |---------------|
    ;               |               |
    ;               |--  Dividend --|
    ;               |               |
    ;               |---------------|
    ;               |  ReturnAddr** |
    ;       ESP---->|---------------|
    ;

    ;
    ; Set up the local stack for NULL Reminder pointer
    ;
    xor  eax, eax
    push eax

    ;
    ; Set up the local stack for Divisor parameter
    ;
    mov  eax, [esp + 20]
    push eax
    mov  eax, [esp + 20]
    push eax

    ;
    ; Set up the local stack for Dividend parameter
    ;
    mov  eax, [esp + 20]
    push eax
    mov  eax, [esp + 20]
    push eax

    ;
    ; Call native DivS64x64Remainder of BaseLib
    ;
    call DivS64x64Remainder

    ;
    ; Adjust stack
    ;
    add  esp, 20

    ret  16
  }
}

//////////////////////////////////////////////////////////////////////////
// _aulldiv
//////////////////////////////////////////////////////////////////////////
/*
 * Divides a 64-bit unsigned value with a 64-bit unsigned value and returns
 * a 64-bit unsigned result.
 */
__declspec(naked) void __cdecl _aulldiv (void)
{
  //
  // Wrapper Implementation over EDKII DivU64x64Reminder() routine
  //    UINT64
  //    EFIAPI
  //    DivU64x64Remainder (
  //      IN      UINT64     Dividend,
  //      IN      UINT64     Divisor,
  //      OUT     UINT64     *Remainder  OPTIONAL
  //      )
  //
  _asm {

    ; Original local stack when calling _aulldiv
    ;               -----------------
    ;               |               |
    ;               |---------------|
    ;               |               |
    ;               |--  Divisor  --|
    ;               |               |
    ;               |---------------|
    ;               |               |
    ;               |--  Dividend --|
    ;               |               |
    ;               |---------------|
    ;               |  ReturnAddr** |
    ;       ESP---->|---------------|
    ;

    ;
    ; Set up the local stack for NULL Reminder pointer
    ;
    xor  eax, eax
    push eax

    ;
    ; Set up the local stack for Divisor parameter
    ;
    mov  eax, [esp + 20]
    push eax
    mov  eax, [esp + 20]
    push eax

    ;
    ; Set up the local stack for Dividend parameter
    ;
    mov  eax, [esp + 20]
    push eax
    mov  eax, [esp + 20]
    push eax

    ;
    ; Call native DivU64x64Remainder of BaseLib
    ;
    call DivU64x64Remainder

    ;
    ; Adjust stack
    ;
    add  esp, 20

    ret  16
  }
}

//////////////////////////////////////////////////////////////////////////
// _aullrem
//////////////////////////////////////////////////////////////////////////
/*
 * Divides a 64-bit unsigned value by another 64-bit unsigned value and returns
 * the 64-bit unsigned remainder.
 */
__declspec(naked) void __cdecl _aullrem(void)
{
  //
  // Wrapper Implementation over EDKII DivU64x64Remainder() routine
  //    UINT64
  //    EFIAPI
  //    DivU64x64Remainder (
  //      IN      UINT64     Dividend,
  //      IN      UINT64     Divisor,
  //      OUT     UINT64     *Remainder  OPTIONAL
  //      )
  //
  _asm {
    ; Original local stack when calling _aullrem
    ;               -----------------
    ;               |               |
    ;               |---------------|
    ;               |               |
    ;               |--  Divisor  --|
    ;               |               |
    ;               |---------------|
    ;               |               |
    ;               |--  Dividend --|
    ;               |               |
    ;               |---------------|
    ;               |  ReturnAddr** |
    ;       ESP---->|---------------|
    ;

    ;
    ; Set up the local stack for Reminder pointer
    ;
    sub  esp, 8
    push esp

    ;
    ; Set up the local stack for Divisor parameter
    ;
    mov  eax, [esp + 28]
    push eax
    mov  eax, [esp + 28]
    push eax

    ;
    ; Set up the local stack for Dividend parameter
    ;
    mov  eax, [esp + 28]
    push eax
    mov  eax, [esp + 28]
    push eax

    ;
    ; Call native DivU64x64Remainder of BaseLib
    ;
    call DivU64x64Remainder

    ;
    ; Put the Reminder in EDX:EAX as return value
    ;
    mov  eax, [esp + 20]
    mov  edx, [esp + 24]

    ;
    ; Adjust stack
    ;
    add  esp, 28

    ret  16
  }
}

#endif