[M3commit] CVS Update: cm3

[Jay K]

 >
 > > > Turning it on all the time makes things much slower and I think also actually breaks things (!).
 >
 > > Yikes, really?
 > 
 > It definitely slows things down.
 > I'm pretty sure when I don't use bitfield refs, I get bad code.
 > I have to try again.
 > I don't have things well automated in terms of keeping around various configurations
 > and easily switching them, and I often go overboard and build too much and don't
 >  do a good job of reducing the problem, but "stare" at too much.

I tested this again.
Of course, it isn't enable-checking that generates bad code.
But the "safe" non-bitfield code now does -- produces a crashing cm3 I386_DARWIN.
I haven't looked into it, just that I tried it again.


It also still generates less efficient code, at least when not optmizing.
The add is a separate instruction, instead of building it in as an offset
into the dereferencing instruction. You probably know that already.


Perhaps the problem is applying the non-bitfield code for, um, bitfields?
For offsets/sizes that aren't multiples of BITS_PER_UNIT?
(er..I guess only offsets are relevant here).
I'll try that.


 - Jay