[dart2wasm] Optimize RTT data structures

This CL optimizes the RTT data structures by * Having a canonical table for substitution arrays * Stores the (canonical) substitution index to use right next to the super class id, thereby * Removing an indirection when looking up substitutions See more information in `sdk/lib/_internal/wasm/lib/type.dart` This reduces * `Hello.Compile.Size.wasm.opt` by ~ 4% * `FluteComplex.Compile.Size.wasm.opt` by ~0.5% Issue #55516 Change-Id: If0a50780a9a604886bd67a08a2f345103f0bcb32 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/369641 Reviewed-by: Ömer Ağacan <[email protected]> Commit-Queue: Martin Kustermann <[email protected]>
dart-lang · Jun 8, 2024 · 1e60700 · 1e60700
1 parent 6424397
commit 1e60700
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diff --git a/pkg/dart2wasm/lib/intrinsics.dart b/pkg/dart2wasm/lib/intrinsics.dart
@@ -10,6 +10,7 @@ import 'class_info.dart';
 import 'code_generator.dart';
 import 'dynamic_forwarders.dart';
 import 'translator.dart';
+import 'types.dart';
 
 typedef CodeGenCallback = void Function(CodeGenerator);
 
@@ -112,6 +113,7 @@ class Intrinsifier {
   };
 
   Translator get translator => codeGen.translator;
+  Types get types => codeGen.translator.types;
   w.InstructionsBuilder get b => codeGen.b;
 
   DartType dartTypeOf(Expression exp) => codeGen.dartTypeOf(exp);
@@ -444,11 +446,29 @@ class Intrinsifier {
           b.i32_const(0);
           return w.NumType.i32;
         case "_typeRulesSupers":
-          return translator.types.makeTypeRulesSupers(b);
-        case "_typeRulesSubstitutions":
-          return translator.types.makeTypeRulesSubstitutions(b);
+          final type = translator
+              .translateStorageType(types.rtt.typeRulesSupersType)
+              .unpacked;
+          translator.constants
+              .instantiateConstant(null, b, types.rtt.typeRulesSupers, type);
+          return type;
+        case "_canonicalSubstitutionTable":
+          final type = translator
+              .translateStorageType(types.rtt.substitutionTableConstantType)
+              .unpacked;
+          translator.constants.instantiateConstant(
+              null, b, types.rtt.substitutionTableConstant, type);
+          return type;
         case "_typeNames":
-          return translator.types.makeTypeNames(b);
+          final type =
+              translator.translateStorageType(types.rtt.typeNamesType).unpacked;
+          if (translator.options.minify) {
+            b.ref_null((type as w.RefType).heapType);
+          } else {
+            translator.constants
+                .instantiateConstant(null, b, types.rtt.typeNames, type);
+          }
+          return type;
       }
     }