audk/StdLib/LibC/CRT/Ia32/ulldvrm.c

101 lines
2.7 KiB
C

/** @file
64-bit Math Worker Function.
The 32-bit versions of C compiler generate calls to library routines
to handle 64-bit math. These functions use non-standard calling conventions.
Copyright (c) 2009 - 2011, 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.
**/
#include <Library/BaseLib.h>
/*
* Divides a 64-bit signed value by another 64-bit signed value and returns
* the 64-bit signed result and the 64-bit signed remainder.
*/
__declspec(naked) void __cdecl _aulldvrm(void)
{
//
// Wrapper Implementation over EDKII DivU64x64Remainder() routine
// UINT64
// EFIAPI
// DivU64x64Remainder (
// IN UINT64 Dividend,
// IN UINT64 Divisor,
// OUT UINT64 *Remainder
// )
//
_asm {
; Original local stack when calling _aulldvrm
; -----------------
; | |
; |---------------|
; | |
; |-- Divisor --|
; | |
; |---------------|
; | |
; |-- Dividend --|
; | |
; |---------------|
; | ReturnAddr** |
; ESP---->|---------------|
;
;
; On Exit:
; EDX:EAX contains the quotient (dividend/divisor)
; EBX:ECX contains the remainder (divided % divisor)
; NOTE: this routine removes the parameters from the stack.
;
;
; Set up the local stack for Remainder pointer
;
sub esp, 8
push esp
;
; Set up the local stack for Divisor parameter
;
mov eax, [esp + 28]
push eax
mov eax, [esp + 28]
push eax
;
; Set up the local stack for Dividend parameter
;
mov eax, [esp + 28]
push eax
mov eax, [esp + 28]
push eax
;
; Call native DivU64x64Remainder of BaseLib
;
call DivU64x64Remainder
;
; EDX:EAX contains the quotient (dividend/divisor)
; Put the Remainder in EBX:ECX
;
mov ecx, [esp + 20]
mov ebx, [esp + 24]
;
; Adjust stack
;
add esp, 28
ret 16
}
}