[llvm] [RISCV] Change vector tuple type's TypeSize to scalable (PR #114329)

[Brandon Wu via llvm-commits]

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@@ -63,6 +63,7 @@ class VTVecTup<int size, int nf, ValueType dummy_elt, int value>
   let NF = nf;
   let ElementType = dummy_elt;
   let isRISCVVecTuple = true;
+  let isScalable = true;
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4vtomat wrote:

Do you mean we should make tuple type a special case and handle it in switch in `getSizeInBits`?

https://github.com/llvm/llvm-project/pull/114329