On Mon, Jan 22, 2018 at 09:22:27AM -0600, Richard Biener wrote: > On Mon, Jan 22, 2018 at 4:01 PM, Wilco Dijkstra <wilco.dijks...@arm.com> > wrote: > > PR79262 has been fixed for almost all AArch64 cpus, however the example is > > still > > vectorized in a few cases, resulting in lower performance. Increase the > > cost of > > vector-to-scalar moves so it is more similar to the other vector costs. As > > a result > > -mcpu=cortex-a53 no longer vectorizes the testcase - libquantum and SPECv6 > > performance improves. > > > > OK for commit? > > It would be better to dissect this cost into vec_to_scalar and vec_extract > where > vec_to_scalar really means getting at the scalar value of a vector of > uniform values > which most targets can do without any instruction (just use a subreg). > > I suppose we could also make vec_to_scalar equal to vector extraction and > remove > the uses for the other case (reduction vector result to scalar reg).
I have dug up Richard's comments from last year, which you appear to have ignored and made no reference to when resubmitting the patch. Please don't do that. Carefully consider Richard's review feedback before resubmitting this patch. To reiterate, it is not OK for trunk. Thanks, James > > Richard. > > > ChangeLog: > > 2018-01-22 Wilco Dijkstra <wdijk...@arm.com> > > > > PR target/79262 > > * config/aarch64/aarch64.c (generic_vector_cost): Adjust > > vec_to_scalar_cost.
