[Bug testsuite/63175] [4.9/5 regression] FAIL: gcc.dg/vect/costmodel/ppc/costmodel-bb-slp-9a.c scan-tree-dump-times slp2" basic block vectorized using SLP" 1

dje at gcc dot gnu.org gcc-bugzilla@gcc.gnu.org
Tue Mar 3 15:05:00 GMT 2015


https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63175

--- Comment #27 from David Edelsohn <dje at gcc dot gnu.org> ---
The vector alignment cost varies with processor implementation, not defined by
the architecture.  Bill has a patch that adjusts unaligned vector cost for
POWER8, which may affect this.  Because this PR depends on the cost model, this
may vary with processor.  Because of the change in cost model usage between 4.8
and 4.9, the code generation will change.  On the other hand, the vectorizer
tuning is encoding x86 preferences.



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