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Re: Why can't CSE recognize const_int's in HIGH LO_SUM pair?
- To: "John David Anglin" <dave at hiauly1 dot hia dot nrc dot ca>
- Subject: Re: Why can't CSE recognize const_int's in HIGH LO_SUM pair?
- From: law at redhat dot com
- Date: Mon, 24 Sep 2001 11:18:28 -0600
- cc: rth at redhat dot com, bernds at redhat dot com, gcc at gcc dot gnu dot org
- Reply-To: law at redhat dot com
In message <200109241702.f8OH2K3T028166@hiauly1.hia.nrc.ca>you write:
> It fixes the fail of 20000731-1.c at -O1. The one clear advantage to
> this approach that I can see is that constants expressed in the above
> form are recognized during jump expansion.
Yes.
Another approach is to allow all constants in compare/branch insns initially,
then use define_splits and friends to lower to the actual capabilities of
the chip later.
jeff