[CFE] Mark initializer as inferred and don't redo work

jensjoha · commit-bot@chromium.org · commit 043885676cfd · 2019-11-18T13:50:43.000Z
No reason to do the same work twice. Change-Id: I8cea469f91dc7087b31bb80352723f0158dcaa6a Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/125402 Commit-Queue: Jens Johansen <jensj@google.com> Reviewed-by: Johnni Winther <johnniwinther@google.com>
diff --git a/pkg/front_end/lib/src/fasta/builder/formal_parameter_builder.dart b/pkg/front_end/lib/src/fasta/builder/formal_parameter_builder.dart
@@ -67,6 +67,8 @@ class FormalParameterBuilder extends ModifierBuilderImpl
   /// [buildOutlineExpressions].
   Token initializerToken;
 
+  bool initializerWasInferred = false;
+
   FormalParameterBuilder(this.metadata, this.modifiers, this.type, this.name,
       LibraryBuilder compilationUnit, int charOffset,
       [Uri fileUri])
@@ -174,6 +176,7 @@ class FormalParameterBuilder extends ModifierBuilderImpl
           .createBodyBuilderForOutlineExpression(
               library, classBuilder, this, scope, fileUri);
       bodyBuilder.constantContext = ConstantContext.required;
+      assert(!initializerWasInferred);
       Expression initializer =
           bodyBuilder.parseFieldInitializer(initializerToken);
       initializer = bodyBuilder.typeInferrer
@@ -184,6 +187,7 @@ class FormalParameterBuilder extends ModifierBuilderImpl
         loader.transformPostInference(variable,
             bodyBuilder.transformSetLiterals, bodyBuilder.transformCollections);
       }
+      initializerWasInferred = true;
       bodyBuilder.resolveRedirectingFactoryTargets();
     }
     initializerToken = null;
diff --git a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
@@ -856,18 +856,21 @@ class BodyBuilder extends ScopeListener<JumpTarget>
         FormalParameterBuilder parameter = formals.parameters[i];
         Expression initializer = parameter.variable.initializer;
         if (parameter.isOptional || initializer != null) {
-          if (parameter.isOptional) {
-            initializer ??= forest.createNullLiteral(
-                // TODO(ahe): Should store: originParameter.fileOffset
-                // https://github.com/dart-lang/sdk/issues/32289
-                noLocation);
+          if (!parameter.initializerWasInferred) {
+            parameter.initializerWasInferred = true;
+            if (parameter.isOptional) {
+              initializer ??= forest.createNullLiteral(
+                  // TODO(ahe): Should store: originParameter.fileOffset
+                  // https://github.com/dart-lang/sdk/issues/32289
+                  noLocation);
+            }
+            VariableDeclaration originParameter = builder.getFormalParameter(i);
+            initializer = typeInferrer?.inferParameterInitializer(
+                this, initializer, originParameter.type);
+            originParameter.initializer = initializer..parent = originParameter;
+            libraryBuilder.loader.transformPostInference(
+                originParameter, transformSetLiterals, transformCollections);
           }
-          VariableDeclaration originParameter = builder.getFormalParameter(i);
-          initializer = typeInferrer?.inferParameterInitializer(
-              this, initializer, originParameter.type);
-          originParameter.initializer = initializer..parent = originParameter;
-          libraryBuilder.loader.transformPostInference(
-              originParameter, transformSetLiterals, transformCollections);
 
           VariableDeclaration extensionTearOffParameter =
               builder.getExtensionTearOffParameter(i);
@@ -3185,7 +3188,9 @@ class BodyBuilder extends ScopeListener<JumpTarget>
             initializer.fileOffset,
             noLength);
       } else {
-        variable.initializer = initializer..parent = variable;
+        if (!parameter.initializerWasInferred) {
+          variable.initializer = initializer..parent = variable;
+        }
       }
     } else if (kind != FormalParameterKind.mandatory) {
       variable.initializer ??= forest.createNullLiteral(noLocation)
