From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeffrey A Law To: Bernd Schmidt Cc: egcs@cygnus.com, scox@cygnus.com Subject: Re: DImode speedup on i386 Date: Sun, 22 Feb 1998 19:58:00 -0000 Message-id: <6549.888205409@hurl.cygnus.com> References: X-SW-Source: 1998-02/msg01044.html In message you write: > > 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. OK. Yea, if you use the same constraints as the existing adddi3 and related patterns you *should* be OK. Looking forward to the updated patch! :-) jeff