Make `call_ref` type annotations mandatory (#5246)

They were optional for a while to allow users to gracefully transition to using
them, but now make them mandatory to match the upstream WasmGC spec.

4 files changed, 18 insertions, 83 deletions

diff --git a/src/wasm-binary.h b/src/wasm-binary.h
index b0128cbc5..192466d07 100644
--- a/src/wasm-binary.h
+++ b/src/wasm-binary.h
@@ -1094,8 +1094,7 @@ enum ASTNodes {
 
   // typed function references opcodes
 
-  CallRefUnannotated = 0x14,
-  CallRef = 0x17,
+  CallRef = 0x14,
   RetCallRef = 0x15,
 
   // gc opcodes
@@ -1743,8 +1742,7 @@ public:
   void visitTryOrTryInBlock(Expression*& out);
   void visitThrow(Throw* curr);
   void visitRethrow(Rethrow* curr);
-  void visitCallRef(CallRef* curr,
-                    std::optional<HeapType> maybeType = std::nullopt);
+  void visitCallRef(CallRef* curr);
   void visitRefAs(RefAs* curr, uint8_t code);
 
   [[noreturn]] void throwError(std::string text);
diff --git a/src/wasm-builder.h b/src/wasm-builder.h
index 1eb31157d..a29867e55 100644
--- a/src/wasm-builder.h
+++ b/src/wasm-builder.h
@@ -1342,35 +1342,6 @@ public:
     }
     return makeBrOn(op, name, ref);
   }
-
-  template<typename T>
-  Expression* validateAndMakeCallRef(Expression* target,
-                                     const T& args,
-                                     bool isReturn = false) {
-    if (target->type != Type::unreachable && !target->type.isRef()) {
-      throw ParseException("Non-reference type for a call_ref", line, col);
-    }
-    // TODO: This won't be necessary once type annotations are mandatory on
-    // call_ref.
-    if (target->type == Type::unreachable ||
-        target->type.getHeapType() == HeapType::nofunc) {
-      // An unreachable target is not supported. Similiar to br_on_cast, just
-      // emit an unreachable sequence, since we don't have enough information
-      // to create a full call_ref.
-      std::vector<Expression*> children;
-      for (auto* arg : args) {
-        children.push_back(makeDrop(arg));
-      }
-      children.push_back(makeDrop(target));
-      children.push_back(makeUnreachable());
-      return makeBlock(children, Type::unreachable);
-    }
-    auto heapType = target->type.getHeapType();
-    if (!heapType.isSignature()) {
-      throw ParseException("Invalid reference type for a call_ref", line, col);
-    }
-    return makeCallRef(target, args, heapType.getSignature().results, isReturn);
-  }
 };
 
 } // namespace wasm
diff --git a/src/wasm/wasm-binary.cpp b/src/wasm/wasm-binary.cpp
index e2bb0075b..782979520 100644
--- a/src/wasm/wasm-binary.cpp
+++ b/src/wasm/wasm-binary.cpp
@@ -3846,15 +3846,12 @@ BinaryConsts::ASTNodes WasmBinaryBuilder::readExpression(Expression*& curr) {
       visitMemoryGrow(grow);
       break;
     }
-    case BinaryConsts::CallRefUnannotated:
-      visitCallRef((curr = allocator.alloc<CallRef>())->cast<CallRef>());
-      break;
     case BinaryConsts::CallRef:
     case BinaryConsts::RetCallRef: {
       auto call = allocator.alloc<CallRef>();
       call->isReturn = code == BinaryConsts::RetCallRef;
       curr = call;
-      visitCallRef(call, getTypeByIndex(getU32LEB()));
+      visitCallRef(call);
       break;
     }
     case BinaryConsts::AtomicPrefix: {
@@ -6851,29 +6848,13 @@ void WasmBinaryBuilder::visitRethrow(Rethrow* curr) {
   curr->finalize();
 }
 
-void WasmBinaryBuilder::visitCallRef(CallRef* curr,
-                                     std::optional<HeapType> maybeType) {
+void WasmBinaryBuilder::visitCallRef(CallRef* curr) {
   BYN_TRACE("zz node: CallRef\n");
   curr->target = popNonVoidExpression();
-  HeapType heapType;
-  if (maybeType) {
-    heapType = *maybeType;
-    if (!Type::isSubType(curr->target->type, Type(heapType, Nullable))) {
-      throwError("Call target has invalid type: " +
-                 curr->target->type.toString());
-    }
-  } else {
-    auto type = curr->target->type;
-    if (type == Type::unreachable) {
-      // If our input is unreachable, then we cannot even find out how many
-      // inputs we have, and just set ourselves to unreachable as well.
-      curr->finalize(type);
-      return;
-    }
-    if (!type.isRef()) {
-      throwError("Non-ref type for a call_ref: " + type.toString());
-    }
-    heapType = type.getHeapType();
+  HeapType heapType = getTypeByIndex(getU32LEB());
+  if (!Type::isSubType(curr->target->type, Type(heapType, Nullable))) {
+    throwError("Call target has invalid type: " +
+               curr->target->type.toString());
   }
   if (!heapType.isSignature()) {
     throwError("Invalid reference type for a call_ref: " + heapType.toString());
diff --git a/src/wasm/wasm-s-parser.cpp b/src/wasm/wasm-s-parser.cpp
index a9fd2de77..ab6230442 100644
--- a/src/wasm/wasm-s-parser.cpp
+++ b/src/wasm/wasm-s-parser.cpp
@@ -2744,35 +2744,20 @@ Expression* SExpressionWasmBuilder::makeTupleExtract(Element& s) {
 }
 
 Expression* SExpressionWasmBuilder::makeCallRef(Element& s, bool isReturn) {
-  Index operandsStart = 1;
-  std::optional<HeapType> sigType;
-  try {
-    sigType = parseHeapType(*s[1]);
-    operandsStart = 2;
-  } catch (ParseException& p) {
-    // The type annotation is required for return_call_ref but temporarily
-    // optional for call_ref.
-    if (isReturn) {
-      throw;
-    }
-  }
+  HeapType sigType = parseHeapType(*s[1]);
   std::vector<Expression*> operands;
-  parseOperands(s, operandsStart, s.size() - 1, operands);
+  parseOperands(s, 2, s.size() - 1, operands);
   auto* target = parseExpression(s[s.size() - 1]);
 
-  if (sigType) {
-    if (!sigType->isSignature()) {
-      throw ParseException(
-        std::string(isReturn ? "return_call_ref" : "call_ref") +
-          " type annotation should be a signature",
-        s.line,
-        s.col);
-    }
-    return Builder(wasm).makeCallRef(
-      target, operands, sigType->getSignature().results, isReturn);
+  if (!sigType.isSignature()) {
+    throw ParseException(
+      std::string(isReturn ? "return_call_ref" : "call_ref") +
+        " type annotation should be a signature",
+      s.line,
+      s.col);
   }
-  return ValidatingBuilder(wasm, s.line, s.col)
-    .validateAndMakeCallRef(target, operands, isReturn);
+  return Builder(wasm).makeCallRef(
+    target, operands, sigType.getSignature().results, isReturn);
 }
 
 Expression* SExpressionWasmBuilder::makeI31New(Element& s) {