projects / mirror_edk2.git / blame
| Commit | Line | Data |
|---|---|---|
| b341712e | 1 | #---------------------------------------------------------------------------\r |
| 2 | #/*++\r | |
| 3 | #\r | |
| 4ea9375a HT |
4 | #Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>\r |
| 5 | #This program and the accompanying materials \r | |
| b341712e | 6 | #are licensed and made available under the terms and conditions of the BSD License \r |
| 7 | #which accompanies this distribution. The full text of the license may be found at \r | |
| 8 | #http://opensource.org/licenses/bsd-license.php \r | |
| 9 | # \r | |
| 10 | #THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, \r | |
| 11 | #WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. \r | |
| 12 | #\r | |
| 13 | #Module Name:\r | |
| 14 | #\r | |
| 15 | # DivU64x32.c\r | |
| 16 | #\r | |
| 17 | #Abstract:\r | |
| 18 | #\r | |
| 19 | # 64-bit division function for IA-32\r | |
| 20 | #\r | |
| 21 | #--*/\r | |
| 22 | \r | |
| 23 | #---------------------------------------------------------------------------\r | |
| 24 | #include "EfiBind.h" //For ASM_PFX\r | |
| 25 | #---------------------------------------------------------------------------\r | |
| 26 | \r | |
| 27 | #---------------------------------------------------------------------------\r | |
| 28 | .386: \r | |
| 29 | .code: \r | |
| 30 | \r | |
| 31 | #---------------------------------------------------------------------------\r | |
| 32 | \r | |
| 33 | .globl ASM_PFX(DivU64x32)\r | |
| 34 | \r | |
| 35 | #UINT64\r | |
| 36 | #DivU64x32 (\r | |
| 37 | # IN UINT64 Dividend,\r | |
| 38 | # IN UINTN Divisor,\r | |
| 39 | # OUT UINTN *Remainder OPTIONAL\r | |
| 40 | # )\r | |
| 41 | #/*++\r | |
| 42 | \r | |
| 43 | #Routine Description:\r | |
| 44 | \r | |
| 45 | # This routine allows a 64 bit value to be divided with a 32 bit value returns \r | |
| 46 | # 64bit result and the Remainder.\r | |
| 47 | #\r | |
| 48 | #Arguments:\r | |
| 49 | \r | |
| 50 | # Dividend - dividend\r | |
| 51 | # Divisor - divisor\r | |
| 52 | # Remainder - buffer for remainder\r | |
| 53 | # \r | |
| 54 | #Returns:\r | |
| 55 | \r | |
| 56 | # Dividend / Divisor\r | |
| 57 | # Remainder = Dividend mod Divisor\r | |
| 58 | # \r | |
| 59 | #N.B. only works for 31bit divisors!!\r | |
| 60 | #\r | |
| 61 | #--*/\r | |
| 62 | #---------------------------------------------------------------------------\r | |
| 63 | \r | |
| 64 | ASM_PFX(DivU64x32):\r | |
| 65 | pushl %ebp\r | |
| 66 | movl %esp, %ebp\r | |
| 67 | xorl %edx, %edx # Clear EDX\r | |
| 68 | \r | |
| 69 | movl 0xC(%ebp), %eax # Put high 32 bits of 64-bit dividend in EAX\r | |
| 70 | movl 0x10(%ebp), %ecx # Put 32 bits divisor in ECX\r | |
| 71 | divl %ecx # Dividend Divisor Quoitent...Remainder\r | |
| 72 | # 0:EAX / ECX = EAX EDX \r | |
| 73 | \r | |
| 74 | pushl %eax # Push quoitent in stack\r | |
| 75 | \r | |
| 76 | movl 8(%ebp), %eax # Put low 32 bits of 64-bit dividend in EAX \r | |
| 77 | divl %ecx # Leave the REMAINDER in EDX as High 32-bit of new dividend\r | |
| 78 | # Dividend Divisor Quoitent...Remainder \r | |
| 79 | # EDX:EAX / ECX = EAX EDX \r | |
| 80 | \r | |
| 81 | movl 0x14(%ebp), %ecx # Put &REMAINDER to ecx\r | |
| 82 | \r | |
| 83 | jecxz Label1 # If ecx == 0, no remainder exist, return with quoitent in EDX directly \r | |
| 84 | movl %edx, (%ecx) # Put EDX through REMAINDER pointer in ECX \r | |
| 85 | \r | |
| 86 | Label1: \r | |
| 87 | popl %edx # Pop High 32-bit QUOITENT to EDX\r | |
| 88 | popl %ebp\r | |
| 89 | \r | |
| 90 | ret\r | |
| 91 | \r |