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

[Simon Pilgrim via llvm-commits]

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@@ -4331,7 +4364,7 @@ BoUpSLP::findReusedOrderedScalars(const BoUpSLP::TreeEntry &TE) {
   if (!isValidElementType(ScalarTy))
     return std::nullopt;
   auto *VecTy = getWidenedType(ScalarTy, NumScalars);
-  int NumParts = TTI->getNumberOfParts(VecTy);
+  int NumParts = TTI->getRegUsageForType(VecTy);
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RKSimon wrote:

Will we always need getNumberOfParts and getRegUsageForType do you think?

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