------- Comment #5 from law at redhat dot com 2006-02-09 02:36 ------- Subject: Re: Missed jump threading opportunity on trees
On Mon, 2006-02-06 at 16:17 +0000, pinskia at gcc dot gnu dot org wrote: > > ------- Comment #3 from pinskia at gcc dot gnu dot org 2006-02-06 16:17 > ------- > the load PRE issue has been fixed but DOM does not thread the jump for some > reason. This patch allows DOM to thread the jump in question (which in effect pulls the conditional out of the loop, definitely a good thing to do when we can). As I mentioned in a previous comment, we were being very conservative when threading across backedges in the CFG. We can be a little more aggressive, specifically we can allow statements in the target block which do not affect the control statement at the end of the target block. This triggered a few more times in my testbucket, so I'm confident it's allowing us to avoid conditionals in at least a few real world hunks of code. Bootstrapped and regression tested on i686-pc-linux-gnu. ------- Comment #6 from law at redhat dot com 2006-02-09 02:36 ------- Created an attachment (id=10812) --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=10812&action=view) -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21417