This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: A bug in vrp_meet?


On 3/5/19 7:44 AM, Richard Biener wrote:

> So fixing it properly with also re-optimize_stmt those stmts so we'd CSE
> the MAX_EXPR introduced by folding makes it somewhat ugly.
> 
> Bootstrapped on x86_64-unknown-linux-gnu, testing in progress.
> 
> Any ideas how to make it less so?  I can split out making optimize_stmt
> take a gsi * btw, in case that's a more obvious change and it makes the
> patch a little smaller.
> 
> Richard.
> 
> 2019-03-05  Richard Biener  <rguenther@suse.de>
> 
>         PR tree-optimization/89595
>         * tree-ssa-dom.c (dom_opt_dom_walker::optimize_stmt): Take
>         stmt iterator as reference, take boolean output parameter to
>         indicate whether the stmt was removed and thus the iterator
>         already advanced.
>         (dom_opt_dom_walker::before_dom_children): Re-iterate over
>         stmts created by folding.
> 
>         * gcc.dg/torture/pr89595.c: New testcase.
> 

Well, all the real logic changs are in the before_dom_children method.
The bits in optimize_stmt are trivial enough to effectively ignore.

I don't see a better way to discover and process statements that are
created in the bowels of fold_stmt.

Jeff


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]