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#include <uefi.h>
void __cdecl atexit() {}
int __cdecl _purecall() { return 0; }
#if defined(_M_IX86)
//////////////////////////////////////////////////////////////////////////
// _allmul
//////////////////////////////////////////////////////////////////////////
__declspec(naked) void __cdecl _allmul(void)
{
_asm {
mov ebx, [esp + 4] ; ebx <- M1[0..31]
mov edx, [esp + 12] ; edx <- M2[0..31]
mov ecx, ebx
mov eax, edx
imul ebx, [esp + 16] ; ebx <- M1[0..31] * M2[32..63]
imul edx, [esp + 8] ; edx <- M1[32..63] * M2[0..31]
add ebx, edx ; carries are abandoned
mul ecx ; edx:eax <- M1[0..31] * M2[0..31]
add edx, ebx ; carries are abandoned
ret 16
}
}
//////////////////////////////////////////////////////////////////////////
// _aullmul
//////////////////////////////////////////////////////////////////////////
__declspec(naked) void __cdecl _aullmul()
{
_asm {
mov ebx, [esp + 4] ; ebx <- M1[0..31]
mov edx, [esp + 12] ; edx <- M2[0..31]
mov ecx, ebx
mov eax, edx
imul ebx, [esp + 16] ; ebx <- M1[0..31] * M2[32..63]
imul edx, [esp + 8] ; edx <- M1[32..63] * M2[0..31]
add ebx, edx ; carries are abandoned
mul ecx ; edx:eax <- M1[0..31] * M2[0..31]
add edx, ebx ; carries are abandoned
ret 16
}
}
//////////////////////////////////////////////////////////////////////////
// _alldiv
//////////////////////////////////////////////////////////////////////////
__declspec(naked) void __cdecl _alldiv()
{
_asm {
; Check sign of res
mov ebx, [esp + 8] ; dividend msdw
mov ecx, [esp + 16] ; divisor msdw
xor ebx, ecx
shr ebx, 31
jz _PosRes ; if Result is positive
push 1 ; if is negative
jmp _Preparing
_PosRes:
push 0
; Preparing operands
; Dividend
_Preparing:
mov ecx, [esp + 12]
shr ecx, 31
jz _ChkDvsr ; Divident is positive
mov eax, [esp + 12] ; is negative
mov ecx, [esp + 8]
xor eax, 0xFFFFFFFF
xor ecx, 0xFFFFFFFF
add ecx, 1
jnc _DvntOK
adc eax, 0
_DvntOK:
mov [esp + 12], eax
mov [esp + 8], ecx
; Divisor
_ChkDvsr:
mov ecx, [esp + 20]
shr ecx, 31
jz _Divide ; Divisor is positive
mov eax, [esp + 20] ; is negative
mov ecx, [esp + 16]
xor eax, 0xFFFFFFFF
xor ecx, 0xFFFFFFFF
add ecx, 1
jnc _DvsrOK
adc eax, 0
_DvsrOK:
mov [esp + 20], eax
mov [esp + 16], ecx
_Divide:
mov ecx, [esp + 20] ; ecx <- divisor[32..63]
test ecx, ecx
jnz __DivRemU64x64 ; call __DivRemU64x64 if Divisor > 2^32
mov ecx, [esp + 16] ; ecx <- divisor
mov eax, [esp + 12] ; eax <- dividend[32..63]
xor edx, edx
div ecx ; eax <- quotient[32..63], edx <- remainder
push eax
mov eax, [esp + 12] ; eax <- dividend[0..31]
div ecx ; eax <- quotient[0..31]
pop edx ; edx <- quotient[32..63] - edx:eax
jmp _GetSign
__DivRemU64x64:
mov edx, dword ptr [esp + 12]
mov eax, dword ptr [esp + 8] ; edx:eax <- dividend
mov edi, edx
mov esi, eax ; edi:esi <- dividend
mov ebx, dword ptr [esp + 16] ; ecx:ebx <- divisor
_B:
shr edx, 1
rcr eax, 1
shrd ebx, ecx, 1
shr ecx, 1
jnz _B
div ebx
mov ebx, eax ; ebx <- quotient
mov ecx, [esp + 20] ; ecx <- high dword of divisor
mul dword ptr [esp + 16] ; edx:eax <- quotient * divisor[0..31]
imul ecx, ebx ; ecx <- quotient * divisor[32..63]
add edx, ecx ; edx <- (quotient * divisor)[32..63]
;mov ecx, dword ptr [esp + 32] ; ecx <- addr for Remainder
jc _TooLarge ; product > 2^64
cmp edi, edx ; compare high 32 bits
ja _Correct
jb _TooLarge ; product > dividend
cmp esi, eax
jae _Correct ; product <= dividend
_TooLarge:
dec ebx ; adjust quotient by -1
jecxz _Return ; return if Remainder == NULL
sub eax, dword ptr [esp + 16]
sbb edx, dword ptr [esp + 20] ; edx:eax <- (quotient - 1) * divisor
_Correct:
jecxz _Return
sub esi, eax
sbb edi, edx ; edi:esi <- remainder
;mov [ecx], esi
;mov [ecx + 4], edi
_Return:
mov eax, ebx ; eax <- quotient
xor edx, edx ; quotient is 32 bits long
; Get sign of result
_GetSign:
pop ecx ; Sign of res
jecxz _Rtrn ; Result is positive
xor eax, 0xFFFFFFFF
xor edx, 0xFFFFFFFF
add eax, 1 ; edx:eax
jnc _Rtrn
adc edx, 0
_Rtrn:
ret 16
}
}
//////////////////////////////////////////////////////////////////////////
// _aulldiv
//////////////////////////////////////////////////////////////////////////
__declspec(naked) void __cdecl _aulldiv()
{
_asm {
mov ecx, [esp + 16] ; ecx <- divisor[32..63]
test ecx, ecx
jnz __DivRemU64x64 ; call __DivRemU64x64 if Divisor > 2^32
mov ecx, [esp + 12] ; ecx <- divisor
mov eax, [esp + 8] ; eax <- dividend[32..63]
xor edx, edx
div ecx ; eax <- quotient[32..63], edx <- remainder
push eax
mov eax, [esp + 8] ; eax <- dividend[0..31]
div ecx ; eax <- quotient[0..31]
pop edx ; edx <- quotient[32..63]
ret 16
__DivRemU64x64:
mov edx, dword ptr [esp + 8]
mov eax, dword ptr [esp + 4] ; edx:eax <- dividend
mov edi, edx
mov esi, eax ; edi:esi <- dividend
mov ebx, dword ptr [esp + 12] ; ecx:ebx <- divisor
_B:
shr edx, 1
rcr eax, 1
shrd ebx, ecx, 1
shr ecx, 1
jnz _B
div ebx
mov ebx, eax ; ebx <- quotient
mov ecx, [esp + 16] ; ecx <- high dword of divisor
mul dword ptr [esp + 12] ; edx:eax <- quotient * divisor[0..31]
imul ecx, ebx ; ecx <- quotient * divisor[32..63]
add edx, ecx ; edx <- (quotient * divisor)[32..63]
;mov ecx, dword ptr [esp + 32] ; ecx <- addr for Remainder
jc _TooLarge ; product > 2^64
cmp edi, edx ; compare high 32 bits
ja _Correct
jb _TooLarge ; product > dividend
cmp esi, eax
jae _Correct ; product <= dividend
_TooLarge:
dec ebx ; adjust quotient by -1
jecxz _Return ; return if Remainder == NULL
sub eax, dword ptr [esp + 12]
sbb edx, dword ptr [esp + 16] ; edx:eax <- (quotient - 1) * divisor
_Correct:
jecxz _Return
sub esi, eax
sbb edi, edx ; edi:esi <- remainder
;mov [ecx], esi
;mov [ecx + 4], edi
_Return:
mov eax, ebx ; eax <- quotient
xor edx, edx ; quotient is 32 bits long
ret 16
}
}
UINT64
EFIAPI
DivU64x64Remainder(
IN UINT64 Dividend,
IN UINT64 Divisor,
OUT UINT64 *Remainder OPTIONAL
);
/*
* Divides a 64-bit unsigned value by another 64-bit unsigned value and returns
* the 64-bit unsigned remainder.
*/
__declspec(naked) void __cdecl _aullrem(void)
{
//
// Wrapper Implementation over EDKII DivU64x64Remainder() routine
// UINT64
// EFIAPI
// DivU64x64Remainder (
// IN UINT64 Dividend,
// IN UINT64 Divisor,
// OUT UINT64 *Remainder OPTIONAL
// )
//
_asm {
; Original local stack when calling _aullrem
; -----------------
; | |
; |---------------|
; | |
; |-- Divisor --|
; | |
; |---------------|
; | |
; |-- Dividend --|
; | |
; |---------------|
; | ReturnAddr** |
; ESP---->|---------------|
;
;
; Set up the local stack for Reminder 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
;
; Put the Reminder in EDX:EAX as return value
;
mov eax, [esp + 20]
mov edx, [esp + 24]
;
; Adjust stack
;
add esp, 28
ret 16
}
}
#endif
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