[llvm] [LV] Handle partial reductions with predication (PR #194859)

[Sander de Smalen via llvm-commits]

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@@ -6804,6 +6840,12 @@ getScaledReductions(VPReductionPHIRecipe *RedPhiR, VPCostContext &CostCtx,
       std::swap(Op, PrevValue);
     }
 
+    // Look for VPBlend(cond_reduce(PrevValue, Op), PrevValue), where
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sdesmalen-arm wrote:

This mentions `cond_reduce`, but should this just be `reduce` ? AIUI, it just checks that the current value (when looking through VPBlend) is the reduction chain.

https://github.com/llvm/llvm-project/pull/194859