[llvm] [RISCV] Fix shift instruction opcodes in getArithmeticInstrCost (PR #156335)

[Craig Topper via llvm-commits]

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@@ -85,14 +85,14 @@ RISCVTTIImpl::getRISCVInstructionCost(ArrayRef<unsigned> OpCodes, MVT VT,
     case RISCV::VFREDUSUM_VS: {
       unsigned VL = VT.getVectorMinNumElements();
       if (!VT.isFixedLengthVector())
-        VL *= *getVScaleForTuning();
+        VL *= getVScaleForTuning().value_or(1);
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topperc wrote:

This change isn't mentioned in the description?

https://github.com/llvm/llvm-project/pull/156335