[llvm] [LoopVectorizer] Add support for chaining partial reductions (PR #120272)

[Sam Tebbs via llvm-commits]

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@@ -8979,7 +8997,9 @@ VPRecipeBuilder::tryToCreatePartialReduction(Instruction *Reduction,
 
   VPValue *BinOp = Operands[0];
   VPValue *Phi = Operands[1];
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SamTebbs33 wrote:

This should probably be called `Accumulator` or something like that since that's now more accurate.

https://github.com/llvm/llvm-project/pull/120272