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#---------------------------------------------------------------------------
#/*++
#
#Copyright (c) 2006, Intel Corporation
#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.
#
#Module Name:
#
# DivU64x32.c
#
#Abstract:
#
# 64-bit division function for IA-32
#
#--*/
#---------------------------------------------------------------------------
#include "EfiBind.h" //For ASM_PFX
#---------------------------------------------------------------------------
#---------------------------------------------------------------------------
.386:
.code:
#---------------------------------------------------------------------------
.globl ASM_PFX(DivU64x32)
#UINT64
#DivU64x32 (
# IN UINT64 Dividend,
# IN UINTN Divisor,
# OUT UINTN *Remainder OPTIONAL
# )
#/*++
#Routine Description:
# This routine allows a 64 bit value to be divided with a 32 bit value returns
# 64bit result and the Remainder.
#
#Arguments:
# Dividend - dividend
# Divisor - divisor
# Remainder - buffer for remainder
#
#Returns:
# Dividend / Divisor
# Remainder = Dividend mod Divisor
#
#N.B. only works for 31bit divisors!!
#
#--*/
#---------------------------------------------------------------------------
ASM_PFX(DivU64x32):
pushl %ebp
movl %esp, %ebp
xorl %edx, %edx # Clear EDX
movl 0xC(%ebp), %eax # Put high 32 bits of 64-bit dividend in EAX
movl 0x10(%ebp), %ecx # Put 32 bits divisor in ECX
divl %ecx # Dividend Divisor Quoitent...Remainder
# 0:EAX / ECX = EAX EDX
pushl %eax # Push quoitent in stack
movl 8(%ebp), %eax # Put low 32 bits of 64-bit dividend in EAX
divl %ecx # Leave the REMAINDER in EDX as High 32-bit of new dividend
# Dividend Divisor Quoitent...Remainder
# EDX:EAX / ECX = EAX EDX
movl 0x14(%ebp), %ecx # Put &REMAINDER to ecx
jecxz Label1 # If ecx == 0, no remainder exist, return with quoitent in EDX directly
movl %edx, (%ecx) # Put EDX through REMAINDER pointer in ECX
Label1:
popl %edx # Pop High 32-bit QUOITENT to EDX
popl %ebp
ret
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