Handle multivalue returns in the interpreter (#2684)

Updates the interpreter to properly flow vectors of values, including
at function boundaries. Adds a small spec test for multivalue return.

1 files changed, 13 insertions, 1 deletions

diff --git a/src/wasm/wasm.cpp b/src/wasm/wasm.cpp
index 64bc5615f..4e4186d08 100644
--- a/src/wasm/wasm.cpp
+++ b/src/wasm/wasm.cpp
@@ -198,7 +198,7 @@ const char* getExpressionName(Expression* curr) {
   WASM_UNREACHABLE("invalid expr id");
 }
 
-Literal getLiteralFromConstExpression(Expression* curr) {
+Literal getSingleLiteralFromConstExpression(Expression* curr) {
   if (auto* c = curr->dynCast<Const>()) {
     return c->value;
   } else if (curr->is<RefNull>()) {
@@ -210,6 +210,18 @@ Literal getLiteralFromConstExpression(Expression* curr) {
   }
 }
 
+Literals getLiteralsFromConstExpression(Expression* curr) {
+  if (auto* t = curr->dynCast<TupleMake>()) {
+    Literals values;
+    for (auto* operand : t->operands) {
+      values.push_back(getSingleLiteralFromConstExpression(operand));
+    }
+    return values;
+  } else {
+    return {getSingleLiteralFromConstExpression(curr)};
+  }
+}
+
 // core AST type checking
 
 struct TypeSeeker : public PostWalker<TypeSeeker> {