getMaxWavesPerEU and getVGPRAllocGranule both changed in GFX10.3 and
they both affect the occupancy calculation.
Differential Revision: https://reviews.llvm.org/D92839
The computation here didn't really make sense to me, and reported
wildy different results depending on the flat work group size
attribute.
I think this should really report a range derived from the possible
work group size bounds, and only allow an occupancy that is a multiple
of the group size.
Previously this would default to 256, not the maximum supported size
of 1024. Using a maximum lower than the hardware maximum requires
language runtimes to enforce this limit for correctness, which no
language has correctly done. Switch the default to the conservatively
correct maximum, and force frontends to opt-in to the more optimal 256
default maximum.
I don't really understand why the changes in occupancy-levels.ll
increased the computed occupancy, which I expected to decrease. I'm
not sure if these tests should be forcing the old maximum.
We had couple places which still return 10 as a maximum
occupancy. Fixed.
Also print comment about occupancy as compiler see it.
Differential Revision: https://reviews.llvm.org/D65423
llvm-svn: 367381
