[llvm] [SLP]Initial support for non-power-of-2 (but still whole register) number of elements in operands. (PR #106449)

[Philip Reames via llvm-commits]

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@@ -3276,8 +3308,9 @@ class BoUpSLP {
                           SmallVectorImpl<Value *> *AltScalars = nullptr) const;
 
     /// Return true if this is a non-power-of-2 node.
-    bool isNonPowOf2Vec() const {
-      bool IsNonPowerOf2 = !has_single_bit(Scalars.size());
+    bool isNonPowOf2Vec(const TargetTransformInfo &TTI) const {
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preames wrote:

Style wise, I object to this particularly part of the change.  Having a vector which can be split into power-of-two pieces (which I think is what you're doing here?), is not the same as that vector *not being a power of two*.  You can adjust the callers to allow this special case if you want, but please revert the API change here.  It makes the code markedly less readable.  

https://github.com/llvm/llvm-project/pull/106449