mirror of https://github.com/acidanthera/audk.git
65 lines
1.7 KiB
C
65 lines
1.7 KiB
C
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/*++
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Copyright (c) 2006, Intel Corporation
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All rights reserved. This program and the accompanying materials
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are licensed and made available under the terms and conditions of the BSD License
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which accompanies this distribution. The full text of the license may be found at
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http://opensource.org/licenses/bsd-license.php
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THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
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WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
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Module Name:
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MultU64x32.c
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Abstract:
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64-bit Multiplication function for IA-32
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--*/
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#include "Tiano.h"
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UINT64
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MultU64x32 (
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IN UINT64 Multiplicand,
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IN UINTN Multiplier
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)
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/*++
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Routine Description:
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This routine allows a 64 bit value to be multiplied with a 32 bit
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value returns 64bit result.
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No checking if the result is greater than 64bits
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Arguments:
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Multiplicand - multiplicand
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Multiplier - multiplier
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Returns:
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Multiplicand * Multiplier
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--*/
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{
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__asm {
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mov eax, dword ptr Multiplicand[0]
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mul Multiplier
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push eax
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push edx
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mov eax, dword ptr Multiplicand[4]
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mul Multiplier
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;
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; The value in edx stored by second multiplication overflows
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; the output and should be discarded. So here we overwrite it
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; with the edx value of first multiplication.
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;
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pop edx
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add edx, eax
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pop eax
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}
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}
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