[llvm] [WebAssembly] Implement lowering calls through funcref to call_ref when available (PR #162227)

[Derek Schuff via llvm-commits]

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@@ -1173,6 +1197,60 @@ static bool callingConvSupported(CallingConv::ID CallConv) {
          CallConv == CallingConv::Swift;
 }
 
+APInt WebAssembly::encodeFunctionSignature(SelectionDAG *DAG, SDLoc &DL,
+                                           SmallVector<MVT, 4> &Returns,
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dschuff wrote:

pre-existing I guess, but can these be `ArrayRef`s? See https://llvm.org/docs/ProgrammersManual.html#llvm-adt-smallvector-h

https://github.com/llvm/llvm-project/pull/162227