[llvm] [LV] Create in-loop sub reductions (PR #147026)

[Sam Tebbs via llvm-commits]

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@@ -627,7 +627,7 @@ for.end:                                          ; preds = %for.body, %entry
   ret float %result.0.lcssa
 }
 
-; Sub we can create a reduction, but not inloop
+; We can create an in-loop reduction for sub-reductions by negating the input
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SamTebbs33 wrote:

Fixed, thank you. And I've added an interleaving run line to the inloop reduction test to make sure nothing breaks the other tests.

https://github.com/llvm/llvm-project/pull/147026