[PATCH] D15408: [AArch64/LoopUnrollRuntime] Don't avoid high-cost trip count computation on the AArch64

[James Molloy via llvm-commits]

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jmolloy added a comment.

Hi,

> I just wan to say on AArch64, division cost is not high for forgiving unrolling oppotunity.


I'm not sure about this. If the loop is inside a loop nest and the inner loop trip count is low, the division could well become significant as on many cores it is not pipelined.

To me, it seems that without any more context (i.e. if we don't have PGO information) it would be better to be more conservative.

James


http://reviews.llvm.org/D15408