[llvm] [SLP] More accurately cost RISCV scalar splats (PR #213104)

[Ryan Buchner via llvm-commits]

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@@ -22075,6 +21861,7 @@ class BoUpSLP::ShuffleInstructionBuilder final : public BaseShuffleAnalysis {
     CommonMask.clear();
     InVectors.clear();
   }
+  void addContextHint(TTI::VectorInstrContext Ctx) { (void)Ctx; }
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bababuck wrote:

What alternative would you suggest? `ShuffleInstructionBuilder` needs to have an `addContextHint` instruction to support the template, but it doesn't use the `Context`.

https://github.com/llvm/llvm-project/pull/213104