mupen64plus-oldsvn/r4300/x86/rjump.c

113 lines
2.9 KiB
C

/**
* Mupen64 - rjump.c
* Copyright (C) 2002 Hacktarux
*
* Mupen64 homepage: http://mupen64.emulation64.com
* email address: hacktarux@yahoo.fr
*
* If you want to contribute to the project please contact
* me first (maybe someone is already making what you are
* planning to do).
*
*
* This program is free software; you can redistribute it and/
* or modify it under the terms of the GNU General Public Li-
* cence as published by the Free Software Foundation; either
* version 2 of the Licence, or any later version.
*
* This program is distributed in the hope that it will be use-
* ful, but WITHOUT ANY WARRANTY; without even the implied war-
* ranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public Licence for more details.
*
* You should have received a copy of the GNU General Public
* Licence along with this program; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139,
* USA.
*
**/
#include <stdlib.h>
#include "../recomp.h"
#include "../r4300.h"
#include "../macros.h"
#include "../ops.h"
#include "../recomph.h"
void dyna_jump()
{
if (stop == 1)
{
dyna_stop();
return;
}
if (PC->reg_cache_infos.need_map)
*return_address = (unsigned long) (PC->reg_cache_infos.jump_wrapper);
else
*return_address = (unsigned long) (actual->code + PC->local_addr);
}
static long save_ebp = 0;
static long save_esp = 0;
static long save_eip = 0;
void dyna_start(void (*code)())
{
/* save the base and stack pointers */
/* make a call and a pop to retrieve the instruction pointer and save it too */
/* then call the code(), which should theoretically never return. */
/* When dyna_stop() sets the *return_address to the saved EIP, the emulator thread will come back here. */
/* It will jump to label 2, restore the base and stack pointers, and exit this function */
#ifdef _WIN32
__asm
{
mov _save_ebp, ebp
mov _save_esp, esp
call point1
jmp point2
point1:
pop eax
mov _save_eip, eax
mov eax, code
call eax
point2:
mov ebp, _save_ebp
mov esp, _save_esp
}
#elif defined(__GNUC__) && defined(__i386__)
asm volatile
(" movl %%ebp, save_ebp \n"
" movl %%esp, save_esp \n"
" call 1f \n"
" jmp 2f \n"
"1: \n"
" popl %%eax \n"
" movl %%eax, save_eip \n"
" call *%%ebx \n"
"2: \n"
" movl save_ebp, %%ebp \n"
" movl save_esp, %%esp \n"
:
: "b" (code)
: "%eax", "memory"
);
#endif
/* clear the registers so we don't return here a second time; that would be a bug */
save_ebp=0;
save_esp=0;
save_eip=0;
}
void dyna_stop()
{
if (save_eip == 0)
printf("Warning: instruction pointer is 0 at dyna_stop()\n");
else
{
*return_address = (unsigned long) save_eip;
}
}