Hal Finkel 3b3c9c3e44 [PPC/LoopUnrollRuntime] Don't avoid high-cost trip count computation on the PPC/A2 ...

On X86 (and similar OOO cores) unrolling is very limited, and even if the
runtime unrolling is otherwise profitable, the expense of a division to compute
the trip count could greatly outweigh the benefits. On the A2, we unroll a lot,
and the benefits of unrolling are more significant (seeing a 5x or 6x speedup
is not uncommon), so we're more able to tolerate the expense, on average, of a
division to compute the trip count.

llvm-svn: 237947

2015-05-21 20:30:23 +00:00

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