[llvm] [SLP]Do not require external uses for roots and single use for other instructions in computeMinimumValueSizes. (PR #72679)

[Simon Pilgrim via llvm-commits]

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@@ -13078,10 +13078,13 @@ bool BoUpSLP::collectValuesToDemote(Value *V,
     return true;
   }
 
-  // If the value is not a vectorized instruction in the expression with only
-  // one use, it cannot be demoted.
+  // If the value is not a vectorized instruction in the expression and not the
+  // used by the insertelement instruction, it cannot be demoted.
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RKSimon wrote:

Is this comment correct? It still doesn't seem right.

https://github.com/llvm/llvm-project/pull/72679