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;/*++
;
;Copyright (c) 2006, 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.
;
;Module Name:
;
; MultU64x32.c
;
;Abstract:
;
; 64-bit Multiplication function for IA-32
;
;--*/
;---------------------------------------------------------------------------
.686
.model flat,C
.code
;---------------------------------------------------------------------------
;UINT64
;MultU64x32 (
; IN UINT64 Multiplicand,
; IN UINTN Multiplier
; )
;/*++
;
;Routine Description:
;
; This routine allows a 64 bit value to be multiplied with a 32 bit
; value returns 64bit result.
; No checking if the result is greater than 64bits
;
;Arguments:
;
; Multiplicand - multiplicand
; Multiplier - multiplier
;
;Returns:
;
; Multiplicand * Multiplier
;
;--*/
MultU64x32 PROC
mov eax, [esp + 4]; dword ptr Multiplicand[0]
mul dword ptr [esp + 0Ch] ; Multiplier
push eax
push edx
mov eax, [esp + 10h]; dword ptr Multiplicand[4]
mul dword ptr [esp + 14h]; Multiplier
;
; The value in edx stored by second multiplication overflows
; the output and should be discarded. So here we overwrite it
; with the edx value of first multiplication.
;
pop edx
add edx, eax
pop eax
ret
MultU64x32 ENDP
END
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