Re: [RFC PATCH 01/11] Add basic support for gcc profilerinstrumentation

[Chris Wright]

* Steven Rostedt (rostedt@xxxxxxxxxxx) wrote:
> On Thu, 3 Jan 2008, Chris Wright wrote:
> > Yes, paravirt ops have a well-specified calling convention (register
> > based).  There was a cleanup that Andi did that caused the problem
> > because it removed all the "fastcall" annotations since -mregparm=3
> > is now always on for i386.  Since MCOUNT disables REGPARM the calling
> > convention changes (caller pushes to stack, callee expects register)
> > chaos ensues.  I sent a patch to fix that quite some months back, but
> > it went stale and I neglected to update it.  Would you like me to dig
> > it up refresh and resend?
> 
> Chris, thanks for the refresher.
> 
> I'm going to see if we can remove the REGPARM hack and change the way
> mcount does its calls. Maybe this will fix things for us.

I don't recall why mcount disables regparm, but I think you're on the
right path to remove that dependency.

thanks,
-chris
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