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

[Sam Tebbs via llvm-commits]

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@@ -7978,6 +7978,12 @@ void SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I,
     return;
   }
   case Intrinsic::experimental_vector_partial_reduce_add: {
+
+    if(!TLI.shouldExpandPartialReductionIntrinsic(&I))) {
+      visitTargetIntrinsic(I, Intrinsic);
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SamTebbs33 wrote:

On second thought, removing this change from this PR would mean adding it to the AArch64 lowering PR which is not the cleanest, or creating a trivially small patch that adds the target hook, which I don't think is worth it, so I think this needs to stay in here.

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