From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bernd Schmidt To: Jeffrey A Law Cc: egcs@cygnus.com, scox@cygnus.com Subject: Re: DImode speedup on i386 Date: Fri, 20 Feb 1998 08:47:00 -0000 Message-id: References: <472.887875330@hurl.cygnus.com> X-SW-Source: 1998-02/msg00952.html > One general note -- you have to be *extremely* careful defining DImode > patterns on the x86 due to the bad interactions with register > reloading. When the patch was written, I simply used the constraints from the addi3/subdi3 patterns to avoid problems. Since it's about a year old (I've tried a couple of times to get it into gcc2, without success), it's quite possible that things have changed. I'll check that and implement Richard Henderson's suggestion, and send an updated patch. Bernd