Message ID | eee4ccb6-983e-f947-9c84-966cf8195299@linux.ibm.com |
---|---|
State | New |
Headers | show |
Series | [testsuite] Fix PR92464 by adjust test case loop bound | expand |
Hi! On Wed, Nov 13, 2019 at 03:31:11PM +0800, Kewen.Lin wrote: > As PR92464 shows, the recent vectorization cost adjustment on load > insns is responsible for this regression. It leads the profitable > min iteration count to change from 19 to 12. The case happens to > hit the threshold. By actual runtime performance evaluation, the > vectorized version perform on par with non vectorized version > (before). So the vectorization on 12 is actually fine. To keep > the case sensitive on high peeling cost, this patch is to adjust > the loop bound from 16 to 14. This is fine, okay for trunk, thanks! Could you add a comment to the testcase saying what it is trying to test exactly? It wasn't obvious to me. Just one or two lines is fine. Segher
Hi Segher, on 2019/11/13 下午6:42, Segher Boessenkool wrote: > Hi! > > On Wed, Nov 13, 2019 at 03:31:11PM +0800, Kewen.Lin wrote: >> As PR92464 shows, the recent vectorization cost adjustment on load >> insns is responsible for this regression. It leads the profitable >> min iteration count to change from 19 to 12. The case happens to >> hit the threshold. By actual runtime performance evaluation, the >> vectorized version perform on par with non vectorized version >> (before). So the vectorization on 12 is actually fine. To keep >> the case sensitive on high peeling cost, this patch is to adjust >> the loop bound from 16 to 14. > > This is fine, okay for trunk, thanks! > > Could you add a comment to the testcase saying what it is trying to test > exactly? It wasn't obvious to me. Just one or two lines is fine. > Thanks! Done with additional comments, committed in r278195. BR, Kewen
diff --git a/gcc/testsuite/gcc.dg/vect/costmodel/ppc/costmodel-vect-76b.c b/gcc/testsuite/gcc.dg/vect/costmodel/ppc/costmodel-vect-76b.c index 4a7da2e..1bb064e 100644 --- a/gcc/testsuite/gcc.dg/vect/costmodel/ppc/costmodel-vect-76b.c +++ b/gcc/testsuite/gcc.dg/vect/costmodel/ppc/costmodel-vect-76b.c @@ -4,7 +4,7 @@ #include <stdarg.h> #include "../../tree-vect.h" -#define N 16 +#define N 14 #define OFF 4 /* Check handling of accesses for which the "initial condition" -