Re: [Tuxnes-devel] more help w/ asm

[Mike M. <mel...@pc...>]

On Wed, 11 Apr 2001, Jim Ursetto wrote:

> I am curious---what exactly are you doing?  Are you
> trying to port the dynamic recompiler?  I don't mean to
> discourage you, but surely it would be easier to use
> a C or asm interpreter, because the dynamic recompiler,
> although really cool, is also really hard to
> understand.  For the SH-4 arch, I ripped out the

	I already tried to discourage him and he still expressed interest
in "porting" the dyn-rec engine to the MIPS ISA. Thus, I admire his
motivation...:) Actually, it's not really porting. The primary issue
involved is writing a new opcode translation table as well as a new
ASM linkage file (such as x86.S).

> recompiler and replaced it with a GPL'ed C core taken
> from nosefart, which was substantially easier, although
> with some speed cost.  This could be reimplemented in
> assembly for some speedup (though it'd still be interpreted).
> You could always port the recompiler later.

	But people really, really like the dyn-rec approach because, as
you noted, it's cool. It's difficult, sure, but if someone wants to go for
it, great.

	After the next release, I want to take TuxNES in a direction that
utilizes the dyn-rec approach, if available, and can fall back on a
portable core. Also, having a portable core will be the default option for
games that use certain mappers (such as MMC5) that currently can't be
emulated in TuxNES due to limitations in the dyn-rec approach.

-- 
	-Mike Melanson