[Yhc] FInfo->codesize woes.

Tom Shackell shackell at cs.york.ac.uk
Mon Feb 4 10:07:59 EST 2008

Stewart Platt wrote:
> Thanks for the reply Tom (and in reply to your message, I am modifying 
> the interpreter)!

Yes, I think that's probably going to be the easiest way forward, all 
the loading code etc is quite fiddly and there's no need to duplicate it :-)

> Aha, seems I threw something of a red herring with the 0x24, it was in 
> fact decimal 24.

Ah, I'd wondered if that might be the case :-)

> Judging from my current output (Warning, assembly): 
> http://modseven.de/pastebin.php?id=1802
> something went wrong around the NEED_HEAP_32 / UNPACK area.

Indeed, you seem to have lost a few instructions, some of the earlier 
ones seem to be out of order as well, though that could be deliberate :-)

Looking at the assembly is interesting, looking good so far. There are 
some definite possibilities for optimization such as keeping the stack 
pointer in a register, and not using CALL to do MK_AP, NEED_HEAP, EVAL 
etc. Though you may well have these things in mind already :-)

One thing to be careful of is RETURN_EVAL, this is because it should 
implement tail call optimisation, which can be fiddly. Of course your 
example doesn't include any assembly for it, so it might be correct 
already :-)

Anyway, good luck, I'll be interested to hear how it goes :-)


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