[Parser] Parse RefAs expressions (#6101)

5 files changed, 14 insertions, 3 deletions

diff --git a/src/parser/contexts.h b/src/parser/contexts.h
index 4147f7bda..aa207fcd5 100644
--- a/src/parser/contexts.h
+++ b/src/parser/contexts.h
@@ -446,6 +446,7 @@ struct NullInstrParserCtx {
   template<typename HeapTypeT> Result<> makeArrayFill(Index, HeapTypeT) {
     return Ok{};
   }
+  Result<> makeRefAs(Index, RefAsOp) { return Ok{}; }
 };
 
 // Phase 1: Parse definition spans for top-level module elements and determine
@@ -1352,6 +1353,10 @@ struct ParseDefsCtx : TypeParserCtx<ParseDefsCtx> {
   Result<> makeArrayFill(Index pos, HeapType type) {
     return withLoc(pos, irBuilder.makeArrayFill(type));
   }
+
+  Result<> makeRefAs(Index pos, RefAsOp op) {
+    return withLoc(pos, irBuilder.makeRefAs(op));
+  }
 };
 
 } // namespace wasm::WATParser
diff --git a/src/parser/parsers.h b/src/parser/parsers.h
index e2fb3732a..610e2953a 100644
--- a/src/parser/parsers.h
+++ b/src/parser/parsers.h
@@ -1425,7 +1425,7 @@ template<typename Ctx> Result<> makeArrayInitElem(Ctx& ctx, Index pos) {
 }
 
 template<typename Ctx> Result<> makeRefAs(Ctx& ctx, Index pos, RefAsOp op) {
-  return ctx.in.err("unimplemented instruction");
+  return ctx.makeRefAs(pos, op);
 }
 
 template<typename Ctx>
diff --git a/src/wasm-ir-builder.h b/src/wasm-ir-builder.h
index 64ee0d62e..24b430e25 100644
--- a/src/wasm-ir-builder.h
+++ b/src/wasm-ir-builder.h
@@ -170,7 +170,7 @@ public:
   [[nodiscard]] Result<> makeArrayFill(HeapType type);
   // [[nodiscard]] Result<> makeArrayInitData();
   // [[nodiscard]] Result<> makeArrayInitElem();
-  // [[nodiscard]] Result<> makeRefAs();
+  [[nodiscard]] Result<> makeRefAs(RefAsOp op);
   // [[nodiscard]] Result<> makeStringNew();
   // [[nodiscard]] Result<> makeStringConst();
   // [[nodiscard]] Result<> makeStringMeasure();
diff --git a/src/wasm.h b/src/wasm.h
index dbedc05f4..47cc047bb 100644
--- a/src/wasm.h
+++ b/src/wasm.h
@@ -1760,6 +1760,7 @@ public:
 
 class RefAs : public SpecificExpression<Expression::RefAsId> {
 public:
+  RefAs() = default;
   RefAs(MixedArena& allocator) {}
 
   RefAsOp op;
diff --git a/src/wasm/wasm-ir-builder.cpp b/src/wasm/wasm-ir-builder.cpp
index cc2bfb433..843e0ed78 100644
--- a/src/wasm/wasm-ir-builder.cpp
+++ b/src/wasm/wasm-ir-builder.cpp
@@ -1048,7 +1048,12 @@ Result<> IRBuilder::makeArrayFill(HeapType type) {
 
 // Result<> IRBuilder::makeArrayInitElem() {}
 
-// Result<> IRBuilder::makeRefAs() {}
+Result<> IRBuilder::makeRefAs(RefAsOp op) {
+  RefAs curr;
+  CHECK_ERR(visitRefAs(&curr));
+  push(builder.makeRefAs(op, curr.value));
+  return Ok{};
+}
 
 // Result<> IRBuilder::makeStringNew() {}