[dart2wasm] Cleanup some code in RTT

Instead of carrying around the instance constants and their type, we
make an extension method allowing one to access the type of an instance
constant.

Change-Id: Ia5c718d4c8779abf154c095a64a967df70b22ced
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/392941
Reviewed-by: Ömer Ağacan <[email protected]>
Commit-Queue: Martin Kustermann <[email protected]>

Author: mkustermann

pkg/dart2wasm/lib/intrinsics.dart

@@ -803,28 +803,32 @@ class Intrinsifier {
           return w.NumType.i32;
         case "_typeRowDisplacementOffsets":
           final type = translator
-              .translateStorageType(types.rtt.typeRowDisplacementOffsetsType)
+              .translateStorageType(
+                  types.rtt.typeRowDisplacementOffsets.interfaceType)
               .unpacked;
           translator.constants.instantiateConstant(
               b, types.rtt.typeRowDisplacementOffsets, type);
           return type;
         case "_typeRowDisplacementTable":
           final type = translator
-              .translateStorageType(types.rtt.typeRowDisplacementTableType)
+              .translateStorageType(
+                  types.rtt.typeRowDisplacementTable.interfaceType)
               .unpacked;
           translator.constants
               .instantiateConstant(b, types.rtt.typeRowDisplacementTable, type);
           return type;
         case "_typeRowDisplacementSubstTable":
           final type = translator
-              .translateStorageType(types.rtt.typeRowDisplacementSubstTableType)
+              .translateStorageType(
+                  types.rtt.typeRowDisplacementSubstTable.interfaceType)
               .unpacked;
           translator.constants.instantiateConstant(
               b, types.rtt.typeRowDisplacementSubstTable, type);
           return type;
         case "_typeNames":
-          final type =
-              translator.translateStorageType(types.rtt.typeNamesType).unpacked;
+          final type = translator
+              .translateStorageType(types.rtt.typeNames.interfaceType)
+              .unpacked;
           if (translator.options.minify) {
             b.ref_null((type as w.RefType).heapType);
           } else {

pkg/dart2wasm/lib/types.dart

@@ -1041,16 +1041,12 @@ class RuntimeTypeInformation {
 
   /// Table of type names indexed by class id.
   late final InstanceConstant typeNames;
-  late final DartType typeNamesType;
 
   /// See sdk/lib/_internal/wasm/lib/type.dart:_typeRowDisplacement*
   /// for what this contains and how it's used for substitution.
   late final InstanceConstant typeRowDisplacementOffsets;
-  late final DartType typeRowDisplacementOffsetsType;
   late final InstanceConstant typeRowDisplacementTable;
-  late final DartType typeRowDisplacementTableType;
   late final InstanceConstant typeRowDisplacementSubstTable;
-  late final DartType typeRowDisplacementSubstTableType;
 
   CoreTypes get coreTypes => translator.coreTypes;
   Types get types => translator.types;
@@ -1210,12 +1206,8 @@ class RuntimeTypeInformation {
         InterfaceType(translator.typeClass, Nullability.nonNullable);
     final arrayOfType = InterfaceType(
         translator.wasmArrayClass, Nullability.nonNullable, [typeType]);
-    final arrayOfArrayOfType = InterfaceType(
-        translator.wasmArrayClass, Nullability.nonNullable, [arrayOfType]);
     final wasmI32 =
         InterfaceType(translator.wasmI32Class, Nullability.nonNullable);
-    final arrayOfI32 = InterfaceType(
-        translator.wasmArrayClass, Nullability.nonNullable, [wasmI32]);
 
     final maxId = translator.classIdNumbering.maxClassId;
     int normalize(int value) => (100 * value) ~/ maxId;
@@ -1231,20 +1223,18 @@ class RuntimeTypeInformation {
             ? 0
             : (entry.$2 == noSubstitutionIndex ? -entry.$1 : entry.$1)),
     ]);
-    typeRowDisplacementTableType = arrayOfI32;
+
     typeRowDisplacementSubstTable =
         translator.constants.makeArrayOf(arrayOfType, [
       for (final entry in table)
         _substitutionTableByIndex[
             entry == null ? noSubstitutionIndex : entry.$2],
     ]);
-    typeRowDisplacementSubstTableType = arrayOfArrayOfType;
 
     typeRowDisplacementOffsets = translator.constants.makeArrayOf(wasmI32, [
       for (int classId = 0; classId < translator.classes.length; ++classId)
         IntConstant(rowForSuperclass[classId]?.offset ?? -1),
     ]);
-    typeRowDisplacementOffsetsType = arrayOfI32;
   }
 
   void _initTypeNames() {
@@ -1262,8 +1252,6 @@ class RuntimeTypeInformation {
       }
     }
     typeNames = translator.constants.makeArrayOf(stringType, nameConstants);
-    typeNamesType = InterfaceType(
-        translator.wasmArrayClass, Nullability.nonNullable, [stringType]);
   }
 
   Map<int, List<(Range, int)>> _buildRanges(Map<int, Map<int, int>> map) {
@@ -1355,3 +1343,8 @@ class _FunctionTypeParameterOffsetCollector extends RecursiveVisitor {
     }
   }
 }
+
+extension InstanceConstantInterfaceType on InstanceConstant {
+  InterfaceType get interfaceType =>
+      InterfaceType(classNode, Nullability.nonNullable, typeArguments);
+}