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[RWO]

@Piru

Whouldent you get in trouble if a 68k application used that tick and ended up is a PPC code function.

I can imagine that the Emulator jumping from a 68k function to another 68k function, but crossing over whould lead into trouble.

RWO

[Piru]

@RWO

Whouldent you get in trouble if a 68k application used that tick and ended up is a PPC code function.

No.

I can imagine that the Emulator jumping from a 68k function to another 68k function, but crossing over whould lead into trouble.

It does not. The code is always executed as 68k. If a PPC function is to be called, there needs to be a gate:

#include <emul/emulregs.h>
#include <emul/emulinterface.h>
#include <exec/ports.h>
#include <exec/libraries.h>
#include <clib/debug_protos.h>

void func(void)
{
  struct MsgPort *port    = (APTR) REG_A1;
  struct Library *SysBase = (APTR) REG_A6;
  kprintf("SysBase 0x%lx port 0x%lx\n", SysBase, port);
}

static const struct EmulLibEntry GATEfunc =
{
  TRAP_LIBNR, 0, func
};

...

mp->mp_Node.ln_Type = NT_MSGPORT;
mp->mp_Flags = 3;
mp->mp_SigTask = (APTR) &GATEfunc;
NEWLIST(&mp->mp_MsgList);

And no, it doesn't go thru m68k emulation there. MorphOS is smart enough to spot PPC->m68k->PPC call and skip over the emulation completely. So it's a direct PPC->PPC call in the end, with no performance penalty. This is the whole point of MOS: Have the old API while giving full PPC performance benefits for both old and new apps. Old m68k apps automagically benefit from native libraries, while new PPC apps can continue to use the same API, without performance losses. Naturally you can also create fully PPC native APIs if you wish.

[RWO]

@Piru

Yes I can understad that adding a Trap function in the mp_SigTask will work but I were thinking more in the lines like we have an old program 68k and an old system 68k.. now as time go by the system get upgraded to PPC, then the old program still has a direct address and not a Trap.. in that case I se it fail.

RWO

[Piru]

@RWO

we have an old program 68k and an old system 68k.. now as time go by the system get upgraded to PPC, then the old program still has a direct address and not a Trap.. in that case I se it fail.

Err, no. It won't. Naturally the OS still calls the routine as m68k one.

If there is any OS that will fail in that case, then the OS in question is broken beyond repair. You just can't change the way these things work.

[itix]

Yes I can understad that adding a Trap function in the mp_SigTask will work but I were thinking more in the lines like we have an old program 68k and an old system 68k.. now as time go by the system get upgraded to PPC, then the old program still has a direct address and not a Trap.. in that case I se it fail.

Trap instruction (0xff00 family instructions) is not needed for 68k code. It just only indicates start of PPC code and when there is not trap the stuff is executed in 68k emulation mode.

68k function pointer in the mp_SigTask is not different than 68k function pointer in the h_Entry of struct Hook for example.