[llvm] [WebAssembly] Don't return multivalue when Emscripten EH/SjLj is used (PR #86048)

[Thomas Lively via llvm-commits]

================
@@ -70,12 +71,12 @@ void llvm::computeSignatureVTs(const FunctionType *Ty,
   computeLegalValueVTs(ContextFunc, TM, Ty->getReturnType(), Results);
 
   MVT PtrVT = MVT::getIntegerVT(TM.createDataLayout().getPointerSizeInBits());
-  if (Results.size() > 1 &&
-      !TM.getSubtarget<WebAssemblySubtarget>(ContextFunc).hasMultivalue()) {
+  if (!WebAssembly::canLowerReturn(
+          Results.size(),
+          &TM.getSubtarget<WebAssemblySubtarget>(ContextFunc))) {
     // WebAssembly can't lower returns of multiple values without demoting to
-    // sret unless multivalue is enabled (see
-    // WebAssemblyTargetLowering::CanLowerReturn). So replace multiple return
-    // values with a poitner parameter.
+    // sret unless multivalue is enabled (see WebAssembly::canLowerReturn). So
+    // replace multiple return values with a poitner parameter.
----------------
tlively wrote:

```suggestion
    // replace multiple return values with a pointer parameter.
```

https://github.com/llvm/llvm-project/pull/86048