Intern HeapTypes and clean up types code (#3428)

Interns HeapTypes using the same patterns and utilities already used to intern
Types. This allows HeapTypes to efficiently be compared for equality and hashed,
which may be important for very large struct types in the future. This change
also has the benefit of increasing symmetry between the APIs of Type and
HeapType, which will make the developer experience more consistent. Finally,
this change will make TypeBuilder (#3418) much simpler because it will no longer
have to introduce TypeInfo variants to refer to HeapTypes indirectly.

1 files changed, 33 insertions, 31 deletions

diff --git a/src/wasm/wasm-binary.cpp b/src/wasm/wasm-binary.cpp
index e70dc4a29..25c1eea8c 100644
--- a/src/wasm/wasm-binary.cpp
+++ b/src/wasm/wasm-binary.cpp
@@ -1034,29 +1034,29 @@ void WasmBinaryWriter::writeHeapType(HeapType type) {
     return;
   }
   int ret = 0;
-  switch (type.kind) {
-    case HeapType::FuncKind:
-      ret = BinaryConsts::EncodedHeapType::func;
-      break;
-    case HeapType::ExternKind:
-      ret = BinaryConsts::EncodedHeapType::extern_;
-      break;
-    case HeapType::ExnKind:
-      ret = BinaryConsts::EncodedHeapType::exn;
-      break;
-    case HeapType::AnyKind:
-      ret = BinaryConsts::EncodedHeapType::any;
-      break;
-    case HeapType::EqKind:
-      ret = BinaryConsts::EncodedHeapType::eq;
-      break;
-    case HeapType::I31Kind:
-      ret = BinaryConsts::EncodedHeapType::i31;
-      break;
-    case HeapType::SignatureKind:
-    case HeapType::StructKind:
-    case HeapType::ArrayKind:
-      WASM_UNREACHABLE("TODO: compound GC types");
+  if (type.isBasic()) {
+    switch (type.getBasic()) {
+      case HeapType::func:
+        ret = BinaryConsts::EncodedHeapType::func;
+        break;
+      case HeapType::ext:
+        ret = BinaryConsts::EncodedHeapType::extern_;
+        break;
+      case HeapType::exn:
+        ret = BinaryConsts::EncodedHeapType::exn;
+        break;
+      case HeapType::any:
+        ret = BinaryConsts::EncodedHeapType::any;
+        break;
+      case HeapType::eq:
+        ret = BinaryConsts::EncodedHeapType::eq;
+        break;
+      case HeapType::i31:
+        ret = BinaryConsts::EncodedHeapType::i31;
+        break;
+    }
+  } else {
+    WASM_UNREACHABLE("TODO: compound GC types");
   }
   o << S64LEB(ret); // TODO: Actually s33
 }
@@ -1401,17 +1401,17 @@ HeapType WasmBinaryBuilder::getHeapType() {
   }
   switch (type) {
     case BinaryConsts::EncodedHeapType::func:
-      return HeapType::FuncKind;
+      return HeapType::func;
     case BinaryConsts::EncodedHeapType::extern_:
-      return HeapType::ExternKind;
+      return HeapType::ext;
     case BinaryConsts::EncodedHeapType::exn:
-      return HeapType::ExnKind;
+      return HeapType::exn;
     case BinaryConsts::EncodedHeapType::any:
-      return HeapType::AnyKind;
+      return HeapType::any;
     case BinaryConsts::EncodedHeapType::eq:
-      return HeapType::EqKind;
+      return HeapType::eq;
     case BinaryConsts::EncodedHeapType::i31:
-      return HeapType::I31Kind;
+      return HeapType::i31;
     default:
       throwError("invalid wasm heap type: " + std::to_string(type));
   }
@@ -5630,7 +5630,8 @@ bool WasmBinaryBuilder::maybeVisitStructGet(Expression*& out, uint32_t code) {
     default:
       return false;
   }
-  auto type = getHeapType();
+  // This type annotation is unused. Beware it needing to be used in the future!
+  getHeapType();
   curr->index = getU32LEB();
   curr->ref = popNonVoidExpression();
   curr->finalize();
@@ -5643,7 +5644,8 @@ bool WasmBinaryBuilder::maybeVisitStructSet(Expression*& out, uint32_t code) {
     return false;
   }
   auto* curr = allocator.alloc<StructSet>();
-  auto type = getHeapType();
+  // This type annotation is unused. Beware it needing to be used in the future!
+  getHeapType();
   curr->index = getU32LEB();
   curr->ref = popNonVoidExpression();
   curr->value = popNonVoidExpression();