audk/EdkCompatibilityPkg/Foundation/Library/EfiCommonLib/Ia32/MultU64x32.S

72 lines
2.0 KiB
ArmAsm

#/*++
#
#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:
#
# MultU64x32.c
#
#Abstract:
#
# 64-bit Multiplication function for IA-32
#
#--*/
#include "EfiBind.h"
#---------------------------------------------------------------------------
.686:
#.MODEL flat,C
.code:
#---------------------------------------------------------------------------
.globl ASM_PFX(MultU64x32)
#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
#
#--*/
ASM_PFX(MultU64x32):
movl 4(%esp), %eax # dword ptr Multiplicand[0]
mull 0xC(%esp) # Multiplier
pushl %eax
pushl %edx
movl 0x10(%esp), %eax # dword ptr Multiplicand[4]
mull 0x14(%esp) # 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.
#
popl %edx
addl %eax, %edx
popl %eax
ret
#MultU64x32 ENDP