[clang] [llvm] [NFC][LLVM] Refactor IRBuilder::Create{VScale,ElementCount,TypeSize}. (PR #142803)

[Paul Walker via llvm-commits]

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@@ -4793,11 +4793,7 @@ Value *CodeGenFunction::EmitAArch64SVEBuiltinExpr(unsigned BuiltinID,
   case SVE::BI__builtin_sve_svlen_u64: {
     SVETypeFlags TF(Builtin->TypeModifier);
     auto VTy = cast<llvm::VectorType>(getSVEType(TF));
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paulwalker-arm wrote:

It turns out `getSVEType()` already returns the correct type to I've remove the redundant cast here, plus the one a few lines lower.

https://github.com/llvm/llvm-project/pull/142803