Re: [PATCH] Fix PR77937

2016-10-17 Thread Bill Schmidt
> On Oct 17, 2016, at 3:27 AM, Richard Biener > wrote: > > On Fri, Oct 14, 2016 at 3:51 PM, Bill Schmidt > wrote: >> Hi Richard, >> >>> On Oct 14, 2016, at 4:19 AM, Richard Biener >>> wrote: >>> >>> On Thu, Oct 13, 2016 at 5:38 PM, Bill Schmidt >>> wrote: The previous patch for

Re: [PATCH] Fix PR77937

2016-10-17 Thread Richard Biener
On Fri, Oct 14, 2016 at 3:51 PM, Bill Schmidt wrote: > Hi Richard, > >> On Oct 14, 2016, at 4:19 AM, Richard Biener >> wrote: >> >> On Thu, Oct 13, 2016 at 5:38 PM, Bill Schmidt >> wrote: >>> The previous patch for >>> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77937 is necessary, but not >>>

Re: [PATCH] Fix PR77937

2016-10-14 Thread Bill Schmidt
Hi Richard, > On Oct 14, 2016, at 4:19 AM, Richard Biener > wrote: > > On Thu, Oct 13, 2016 at 5:38 PM, Bill Schmidt > wrote: >> The previous patch for >> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77937 is necessary, but not >> sufficient in all cases. It allows -1 to be used with a pointe

Re: [PATCH] Fix PR77937

2016-10-14 Thread Richard Biener
On Thu, Oct 13, 2016 at 5:38 PM, Bill Schmidt wrote: > The previous patch for > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77937 is necessary, but not > sufficient in all cases. It allows -1 to be used with a pointer > increment, which we really do not want given that this is generally not > pr

[PATCH] Fix PR77937

2016-10-13 Thread Bill Schmidt
The previous patch for https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77937 is necessary, but not sufficient in all cases. It allows -1 to be used with a pointer increment, which we really do not want given that this is generally not profitable. Disable this case for now. We can add logic later to

Re: [PATCH] Fix PR77937

2016-10-12 Thread Markus Trippelsdorf
On 2016.10.12 at 20:14 -0500, Bill Schmidt wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77937 reports an ICE in SLSR > where a POINTER_PLUS_EXPR occurs with a candidate increment of -1. This > is supposed to be prevented by code in analyze_increments, since replacement > of such a candida

[PATCH] Fix PR77937

2016-10-12 Thread Bill Schmidt
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77937 reports an ICE in SLSR where a POINTER_PLUS_EXPR occurs with a candidate increment of -1. This is supposed to be prevented by code in analyze_increments, since replacement of such a candidate is not guaranteed to be profitable. The test for this