Remove basic reference types (#4802)

Basic reference types like `Type::funcref`, `Type::anyref`, etc. made it easy to
accidentally forget to handle reference types with the same basic HeapTypes but
the opposite nullability. In principle there is nothing special about the types
with shorthands except in the binary and text formats. Removing these shorthands
from the internal type representation by removing all basic reference types
makes some code more complicated locally, but simplifies code globally and
encourages properly handling both nullable and non-nullable reference types.

1 files changed, 16 insertions, 82 deletions

diff --git a/src/wasm/literal.cpp b/src/wasm/literal.cpp
index 6c7689990..85e93f912 100644
--- a/src/wasm/literal.cpp
+++ b/src/wasm/literal.cpp
@@ -46,11 +46,6 @@ Literal::Literal(Type type) : type(type) {
       case Type::none:
         return;
       case Type::unreachable:
-      case Type::funcref:
-      case Type::anyref:
-      case Type::eqref:
-      case Type::i31ref:
-      case Type::dataref:
         break;
     }
   }
@@ -100,11 +95,6 @@ Literal::Literal(const Literal& other) : type(other.type) {
       case Type::none:
         return;
       case Type::unreachable:
-      case Type::funcref:
-      case Type::anyref:
-      case Type::eqref:
-      case Type::i31ref:
-      case Type::dataref:
         break;
     }
   }
@@ -239,7 +229,7 @@ Literals Literal::makeNegOnes(Type type) {
 Literal Literal::makeZero(Type type) {
   assert(type.isSingle());
   if (type.isRef()) {
-    if (type == Type::i31ref) {
+    if (type.getHeapType() == HeapType::i31) {
       return makeI31(0);
     } else {
       return makeNull(type.getHeapType());
@@ -355,11 +345,6 @@ void Literal::getBits(uint8_t (&buf)[16]) const {
       break;
     case Type::none:
     case Type::unreachable:
-    case Type::funcref:
-    case Type::anyref:
-    case Type::eqref:
-    case Type::i31ref:
-    case Type::dataref:
       WASM_UNREACHABLE("invalid type");
   }
 }
@@ -373,43 +358,37 @@ bool Literal::operator==(const Literal& other) const {
   if (type != other.type) {
     return false;
   }
-  auto compareRef = [&]() {
-    assert(type.isRef());
-    // Note that we've already handled nulls earlier.
-    if (type.isFunction()) {
-      assert(func.is() && other.func.is());
-      return func == other.func;
-    }
-    if (type.isData()) {
-      return gcData == other.gcData;
-    }
-    // other non-null reference type literals cannot represent concrete values,
-    // i.e. there is no concrete anyref or eqref other than null.
-    WASM_UNREACHABLE("unexpected type");
-  };
   if (type.isBasic()) {
     switch (type.getBasic()) {
       case Type::none:
         return true; // special voided literal
       case Type::i32:
       case Type::f32:
-      case Type::i31ref:
         return i32 == other.i32;
       case Type::i64:
       case Type::f64:
         return i64 == other.i64;
       case Type::v128:
         return memcmp(v128, other.v128, 16) == 0;
-      case Type::funcref:
-      case Type::anyref:
-      case Type::eqref:
-      case Type::dataref:
-        return compareRef();
       case Type::unreachable:
         break;
     }
   } else if (type.isRef()) {
-    return compareRef();
+    assert(type.isRef());
+    // Note that we've already handled nulls earlier.
+    if (type.isFunction()) {
+      assert(func.is() && other.func.is());
+      return func == other.func;
+    }
+    if (type.isData()) {
+      return gcData == other.gcData;
+    }
+    if (type.getHeapType() == HeapType::i31) {
+      return i32 == other.i32;
+    }
+    // other non-null reference type literals cannot represent concrete values,
+    // i.e. there is no concrete anyref or eqref other than null.
+    WASM_UNREACHABLE("unexpected type");
   } else if (type.isRtt()) {
     return *rttSupers == *other.rttSupers;
   }
@@ -578,11 +557,6 @@ std::ostream& operator<<(std::ostream& o, Literal literal) {
         o << "i32x4 ";
         literal.printVec128(o, literal.getv128());
         break;
-      case Type::funcref:
-      case Type::anyref:
-      case Type::eqref:
-      case Type::i31ref:
-      case Type::dataref:
       case Type::unreachable:
         WASM_UNREACHABLE("unexpected type");
     }
@@ -801,11 +775,6 @@ Literal Literal::eqz() const {
     case Type::f64:
       return eq(Literal(double(0)));
     case Type::v128:
-    case Type::funcref:
-    case Type::anyref:
-    case Type::eqref:
-    case Type::i31ref:
-    case Type::dataref:
     case Type::none:
     case Type::unreachable:
       WASM_UNREACHABLE("unexpected type");
@@ -824,11 +793,6 @@ Literal Literal::neg() const {
     case Type::f64:
       return Literal(int64_t(i64 ^ 0x8000000000000000ULL)).castToF64();
     case Type::v128:
-    case Type::funcref:
-    case Type::anyref:
-    case Type::eqref:
-    case Type::i31ref:
-    case Type::dataref:
     case Type::none:
     case Type::unreachable:
       WASM_UNREACHABLE("unexpected type");
@@ -847,11 +811,6 @@ Literal Literal::abs() const {
     case Type::f64:
       return Literal(int64_t(i64 & 0x7fffffffffffffffULL)).castToF64();
     case Type::v128:
-    case Type::funcref:
-    case Type::anyref:
-    case Type::eqref:
-    case Type::i31ref:
-    case Type::dataref:
     case Type::none:
     case Type::unreachable:
       WASM_UNREACHABLE("unexpected type");
@@ -987,11 +946,6 @@ Literal Literal::add(const Literal& other) const {
     case Type::f64:
       return standardizeNaN(getf64() + other.getf64());
     case Type::v128:
-    case Type::funcref:
-    case Type::anyref:
-    case Type::eqref:
-    case Type::i31ref:
-    case Type::dataref:
     case Type::none:
     case Type::unreachable:
       WASM_UNREACHABLE("unexpected type");
@@ -1010,11 +964,6 @@ Literal Literal::sub(const Literal& other) const {
     case Type::f64:
       return standardizeNaN(getf64() - other.getf64());
     case Type::v128:
-    case Type::funcref:
-    case Type::anyref:
-    case Type::eqref:
-    case Type::i31ref:
-    case Type::dataref:
     case Type::none:
     case Type::unreachable:
       WASM_UNREACHABLE("unexpected type");
@@ -1112,11 +1061,6 @@ Literal Literal::mul(const Literal& other) const {
     case Type::f64:
       return standardizeNaN(getf64() * other.getf64());
     case Type::v128:
-    case Type::funcref:
-    case Type::anyref:
-    case Type::eqref:
-    case Type::i31ref:
-    case Type::dataref:
     case Type::none:
     case Type::unreachable:
       WASM_UNREACHABLE("unexpected type");
@@ -1347,11 +1291,6 @@ Literal Literal::eq(const Literal& other) const {
     case Type::f64:
       return Literal(getf64() == other.getf64());
     case Type::v128:
-    case Type::funcref:
-    case Type::anyref:
-    case Type::eqref:
-    case Type::i31ref:
-    case Type::dataref:
     case Type::none:
     case Type::unreachable:
       WASM_UNREACHABLE("unexpected type");
@@ -1370,11 +1309,6 @@ Literal Literal::ne(const Literal& other) const {
     case Type::f64:
       return Literal(getf64() != other.getf64());
     case Type::v128:
-    case Type::funcref:
-    case Type::anyref:
-    case Type::eqref:
-    case Type::i31ref:
-    case Type::dataref:
     case Type::none:
     case Type::unreachable:
       WASM_UNREACHABLE("unexpected type");