/** @file
 Copyright (C) 2019, vit9696. All rights reserved.

 All rights reserved.

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

/**
 MultThenDivU64x64x32 is from MdeModulePkg's PciRootBridgeIo.c

 Copyright (c) 1999 - 2018, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 **/
UINT64
MultThenDivU64x64x32 (
  IN  UINT64  Multiplicand,
  IN  UINT64  Multiplier,
  IN  UINT32  Divisor,
  OUT UINT32  *Remainder  OPTIONAL
  )
{
  UINT64                            Uint64;
  UINT32                            LocalRemainder;
  UINT32                            Uint32;
  if (Multiplicand > DivU64x64Remainder (MAX_UINT64, Multiplier, NULL)) {
    //
    // Make sure Multiplicand is the bigger one.
    //
    if (Multiplicand < Multiplier) {
      Uint64       = Multiplicand;
      Multiplicand = Multiplier;
      Multiplier   = Uint64;
    }
    //
    // Because Multiplicand * Multiplier overflows,
    //   Multiplicand * Multiplier / Divisor
    // = (2 * Multiplicand' + 1) * Multiplier / Divisor
    // = 2 * (Multiplicand' * Multiplier / Divisor) + Multiplier / Divisor
    //
    Uint64 = MultThenDivU64x64x32 (RShiftU64 (Multiplicand, 1), Multiplier, Divisor, &LocalRemainder);
    Uint64 = LShiftU64 (Uint64, 1);
    Uint32 = 0;
    if ((Multiplicand & 0x1) == 1) {
      Uint64 += DivU64x32Remainder (Multiplier, Divisor, &Uint32);
    }
    return Uint64 + DivU64x32Remainder (Uint32 + LShiftU64 (LocalRemainder, 1), Divisor, Remainder);
  } else {
    return DivU64x32Remainder (MultU64x64 (Multiplicand, Multiplier), Divisor, Remainder);
  }
}