[PATCH] D70587: [SLP] Enhance SLPVectorizer to vectorize different combinations of aggregates

Mon Nov 25 03:56:24 PST 2019

RKSimon added inline comments.

================
Comment at: llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp:6963
+                                            IE->getType(),
+                                            CI->getZExtValue());
+      }
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anton-afanasyev wrote:
> RKSimon wrote:
> > If the insertion index isn't constant we should call getVectorInstrCost with a ~0/-1 value
> Hmm, what is `~0/-1` value exactly?
> Also, I'm not sure the cost tuning is related to this commit -- the current logic is taken unchanged as it was before.
OK, that's acceptable for now but we should be enabling this for non-const indices as well in a future patch.

getVectorInstrCost recognizes  the 'all bits set' insert/extract index argument as a non-constant index (which on most targets has a high cost).

@spatel is currently looking at this on x86 as part of PR43605

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D70587/new/

https://reviews.llvm.org/D70587