| #--------------------------------------------------------------------------- | |
| #/*++ | |
| # | |
| #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: | |
| # | |
| # 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 | |