[PATCH] enable loop fusion on isl-15

[Mike Stump]

On Dec 4, 2015, at 5:13 AM, Alan Lawrence <alan.lawrence@arm.com> wrote:
> On 05/11/15 21:43, Sebastian Pop wrote:
>>        * graphite-optimize-isl.c (optimize_isl): Call
>>        isl_options_set_schedule_maximize_band_depth.
>> 
>>        * gcc.dg/graphite/fuse-1.c: New.
>>        * gcc.dg/graphite/fuse-2.c: New.
>>        * gcc.dg/graphite/interchange-13.c: Remove bogus check.
> 
> I note that the test
> 
> scan-tree-dump-times forwprop4 "gimple_simplified to[^\\n]*\\^ 12" 1
> 
> FAILs under isl-0.14, with which GCC can still be built and generally claims to work.
> 
> Is it worth trying to detect this in the testsuite, so we can XFAIL it? By which I mean, is there a reasonable testsuite mechanism by which we could do that?

You can permanently ignore it by updating to 0.15?  I don’t see the advantage of bothering to finesse this too much.  I don’t know of a way to detect 14 v 15 other than this test case, but, if you do that, you can’t use that result to gate this test case.  If one wanted to engineer in a way, one would expose the isl version via a preprocessor symbol (built in), and then the test case would use that to gate it.  If we had to fix it, I think I’d prefer we just raise the isl version to 15 or later and be done with it.