[llvm] [RISCV][GISEL] Add support for lowerFormalArguments that contain scalable vector types (PR #70882)

[Craig Topper via llvm-commits]

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@@ -472,7 +473,7 @@ static void buildCopyFromRegs(MachineIRBuilder &B, ArrayRef<Register> OrigRegs,
   } else {
     // Vector was split, and elements promoted to a wider type.
     // FIXME: Should handle floating point promotions.
-    LLT BVType = LLT::fixed_vector(LLTy.getNumElements(), PartLLT);
+    LLT BVType = LLT::vector(LLTy.getElementCount(), PartLLT);
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topperc wrote:

This change doesn't make sense since G_BUILD_VECTOR can't have scalable type.

https://github.com/llvm/llvm-project/pull/70882