[PATCH] D15995: [LTO] Add a run of LoopUnroll

[Hal Finkel via llvm-commits]

hfinkel added a subscriber: hfinkel.

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Comment at: lib/Transforms/IPO/PassManagerBuilder.cpp:576
@@ -573,3 +575,3 @@
   if (EnableLoopInterchange)
     PM.add(createLoopInterchangePass());
 
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joker.eph wrote:
> Note: it is inserted before LoopInterchangePass in the regular pipeline?
> 
> Also there is a comment before another insertion ` // BBVectorize may have significantly shortened a loop body; unroll again.`. Could this be valid for the Loop and SLP vectorizers that are inserted below?
> Also there is a comment before another insertion  // BBVectorize may have significantly shortened a loop body; unroll again.. Could this be valid for the Loop and SLP vectorizers that are inserted below?

Yes, although for the loop vectorizer there is a competing effect: The loop vectorizer does not vectorize loops with known constant trip counts below some threshold (TinyTripCountVectorThreshold - 16 by default).


Repository:
  rL LLVM

http://reviews.llvm.org/D15995