[M3commit] CVS Update: cm3

[Jay K]

Tony, just to be clear..you/I are disturbed by volatile, but it has also, I believe, like always been there.
It has been gone only very briefly, and its non-use is probably limited for other reasons (how many people are
using it, on how many platforms?).


 - Jay

----------------------------------------
> From: jay.krell at cornell.edu
> To: hosking at cs.purdue.edu; jkrell at elego.de
> CC: m3commit at elegosoft.com
> Subject: RE: [M3commit] CVS Update: cm3
> Date: Sun, 4 Jul 2010 00:42:20 +0000
>
>
> Not a multiprocessor.
>   Still interested in selective volatile?
>
>
> This all bothers me too.
> I don't want volatile. It makes the optimized code terrible.
> But I don't want to debug any problem from removing it, beyond compilation failure.
>
>
> I can try a few things.
> This is all wierd. I swear I saw it hang several times.
> I swear I'm trying to to change "too many" variables at a time. Yes, I know, 2 is too many.
>
>
> Once I started getting version stamp mismatch, I resorted to using a cross built cm3.
>  Out of necessity sort of, but that causes more flucuation of variables.
>
> Let me try again with volatile and see if it is solid.
>  Then I'll try with only volatile stores.
>
> I've been trying optimized and unoptimized, and not kept good track of which when.
>
>
>  - Jay
>
>
> ----------------------------------------
> > From: hosking at cs.purdue.edu
> > Date: Sat, 3 Jul 2010 20:36:20 -0400
> > To: jkrell at elego.de
> > CC: m3commit at elegosoft.com
> > Subject: Re: [M3commit] CVS Update: cm3
> >
> > I am very disturbed that volatile is needed here. Can we selectively turn it on for thread-critical files like ThreadPThread and see if it fixes the problem. I wonder if the double-checked locking is broken for PPC memory model. Is this on a multi-processor?
> >
> > On 3 Jul 2010, at 12:57, Jay Krell wrote:
> >
> > > CVSROOT: /usr/cvs
> > > Changes by: jkrell at birch. 10/07/03 12:57:09
> > >
> > > Modified files:
> > > cm3/m3-sys/m3cc/gcc/gcc/m3cg/: parse.c
> > >
> > > Log message:
> > > restore volatile for powerpc and powerpc64 platforms
> > > This seems to fix PPC_LINUX hanging.
> > > This needs further debugging, but I'm not eager.
> > > This will also affect PPC_DARWIN, PPC64_DARWIN, PPC32_OPENBSD,
> > > PPC32_NETBSD, PPC32_FREEBSD, etc., but these platforms are little used or
> > > nonexistant.
> > >
> > > Having volatile like has been the very long standing situation though.
> > > The result is that the optimizer does basically nothing.
> >
>