107 lines
2.0 KiB
C++
107 lines
2.0 KiB
C++
![]() |
/******************************************************************************
|
||
|
|
||
|
COPYRIGHT(C) JONAS 'SORTIE' TERMANSEN 2011.
|
||
|
|
||
|
This file is part of LibMaxsi.
|
||
|
|
||
|
LibMaxsi is free software: you can redistribute it and/or modify it under
|
||
|
the terms of the GNU Lesser General Public License as published by the Free
|
||
|
Software Foundation, either version 3 of the License, or (at your option)
|
||
|
any later version.
|
||
|
|
||
|
LibMaxsi is distributed in the hope that it will be useful, but WITHOUT ANY
|
||
|
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
||
|
FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for
|
||
|
more details.
|
||
|
|
||
|
You should have received a copy of the GNU Lesser General Public License
|
||
|
along with LibMaxsi. If not, see <http://www.gnu.org/licenses/>.
|
||
|
|
||
|
c++.cpp
|
||
|
Implements required C++ stuff for use in the Sortix kernel.
|
||
|
|
||
|
******************************************************************************/
|
||
|
|
||
|
#include "platform.h"
|
||
|
|
||
|
extern "C" void __cxa_pure_virtual()
|
||
|
{
|
||
|
// This shouldn't happen. TODO: Possibly crash the kernel here.
|
||
|
}
|
||
|
|
||
|
#ifdef PLATFORM_X86
|
||
|
|
||
|
// TODO: These two stubs are buggy!
|
||
|
|
||
|
// Divides two 64-bit integers in O(logN). I think.
|
||
|
extern "C" uint64_t __udivdi3(uint64_t A, uint64_t B)
|
||
|
{
|
||
|
uint64_t ACC = 0;
|
||
|
uint64_t R = 0;
|
||
|
uint64_t PWR = 1;
|
||
|
uint64_t EXP = B;
|
||
|
|
||
|
while ( EXP <= A - ACC )
|
||
|
{
|
||
|
R += PWR;
|
||
|
ACC += EXP;
|
||
|
|
||
|
if ( 2 * EXP <= A - ACC )
|
||
|
{
|
||
|
PWR++;
|
||
|
EXP *= 2;
|
||
|
}
|
||
|
else if ( A - ACC < B )
|
||
|
{
|
||
|
break;
|
||
|
}
|
||
|
else
|
||
|
{
|
||
|
while ( A - ACC < EXP )
|
||
|
{
|
||
|
PWR--;
|
||
|
EXP /= 2;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
return R;
|
||
|
}
|
||
|
|
||
|
// Mods two 64-bit integers in O(logN). I think.
|
||
|
extern "C" uint64_t __umoddi3(uint64_t A, uint64_t B)
|
||
|
{
|
||
|
uint64_t ACC = 0;
|
||
|
uint64_t R = 0;
|
||
|
uint64_t PWR = 1;
|
||
|
uint64_t EXP = B;
|
||
|
|
||
|
while ( EXP <= A - ACC )
|
||
|
{
|
||
|
R += PWR;
|
||
|
ACC += EXP;
|
||
|
|
||
|
if ( 2 * EXP <= A - ACC )
|
||
|
{
|
||
|
PWR++;
|
||
|
EXP *= 2;
|
||
|
}
|
||
|
else if ( A - ACC < B )
|
||
|
{
|
||
|
break;
|
||
|
}
|
||
|
else
|
||
|
{
|
||
|
while ( A - ACC < EXP )
|
||
|
{
|
||
|
PWR--;
|
||
|
EXP /= 2;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
return A - ACC;
|
||
|
}
|
||
|
#endif
|
||
|
|