[llvm] [LoopVectorizer] Add support for partial reductions (PR #92418)

[Sam Tebbs via llvm-commits]

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@@ -437,6 +469,15 @@ Value *VPInstruction::generate(VPTransformState &State) {
     Value *Cond = State.get(getOperand(0));
     Value *Op1 = State.get(getOperand(1));
     Value *Op2 = State.get(getOperand(2));
+    auto *CondVec = dyn_cast<VectorType>(Cond->getType());
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SamTebbs33 wrote:

It turns my understanding of how selects work with `<Y x i1>` conditions was entirely wrong so I'll revert these changes and leave supporting predicated loops until later.

https://github.com/llvm/llvm-project/pull/92418