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: Thu, 19 Feb 1998 03:32:00 -0000 Message-id: <472.887875330@hurl.cygnus.com> References: X-SW-Source: 1998-02/msg00918.html In message < Pine.SOL.3.90.980218113225.12315H-100000@bond.informatik.rwth-aachen.de >you write: > > The following patch improves performance of DImode operations on the i386. > For the chess program Crafty, which relies heavily upon those operations, > this patch improved the "nodes per second" count in the built-in benchmark > from 79558 to 93047. It also made the executable 12000 bytes smaller. > > Bernd > > * i386/i386.c (ix86_logical_operator): New function. > (split_di): When splitting a MEM, make sure the new MEMs have > SImode. > * i386/i386.md (xordi3, anddi3, iordi3): New patterns. > Add a define_split to implement them. One general note -- you have to be *extremely* careful defining DImode patterns on the x86 due to the bad interactions with register reloading. I would like Stan's opinion on these patches before they're installed since he had the "pleasure" of dealing with the last round of DImode problems on the x86. jeff