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Re: register class constraints question
- From: DJ Delorie <dj at redhat dot com>
- To: Joern Rennecke <joernr at arc dot com>
- Cc: gcc at gcc dot gnu dot org
- Date: Wed, 08 Oct 2008 20:01:05 -0400
- Subject: Re: register class constraints question
- References: <20081008122012.GB21798@elsdt-razorfish.arc.com>
Joern Rennecke <joernr@arc.com> writes:
> I'm not sure if this changed with IRA,
Acts the same with 4.3 and 4.4.
> reload will look for the alternative with the cheapest total cost of
> alternative and reloads.
This was the key. Disparaging the smaller class's alternative with
'?' works - it avoids the regalloc problem, yet that alternative ends
up being used anyway (coincidence).
Thanks!