Initial multivalue support (#2675)

Implements parsing and emitting of tuple creation and extraction and tuple-typed control flow for both the text and binary formats.

TODO:
 - Extend Precompute/interpreter to handle tuple values
 - C and JS API support/testing
 - Figure out how to lower in stack IR
 - Fuzzing

1 files changed, 18 insertions, 0 deletions

diff --git a/src/wasm/wasm.cpp b/src/wasm/wasm.cpp
index f8874da01..64bc5615f 100644
--- a/src/wasm/wasm.cpp
+++ b/src/wasm/wasm.cpp
@@ -188,6 +188,10 @@ const char* getExpressionName(Expression* curr) {
       return "rethrow";
     case Expression::Id::BrOnExnId:
       return "br_on_exn";
+    case Expression::Id::TupleMakeId:
+      return "tuple.make";
+    case Expression::Id::TupleExtractId:
+      return "tuple.extract";
     case Expression::Id::NumExpressionIds:
       WASM_UNREACHABLE("invalid expr id");
   }
@@ -898,6 +902,20 @@ void Push::finalize() {
   }
 }
 
+void TupleMake::finalize() {
+  std::vector<Type> types;
+  for (auto* op : operands) {
+    if (op->type == Type::unreachable) {
+      type = Type::unreachable;
+      return;
+    }
+    types.push_back(op->type);
+  }
+  type = Type(types);
+}
+
+void TupleExtract::finalize() { type = tuple->type.expand()[index]; }
+
 size_t Function::getNumParams() { return sig.params.size(); }
 
 size_t Function::getNumVars() { return vars.size(); }