Revert "[vm/aot/tfa] Tree shake write-only fields"

This reverts commit ff34fd8.

Reason: crash on the internal app
Issue: flutter/flutter#50745

Change-Id: Ifcfbb38fa04d27558f9e78ca6b2a8637693c7d76
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/135794
Reviewed-by: Alexander Aprelev <[email protected]>
Commit-Queue: Alexander Markov <[email protected]>

Author: alexmarkov

pkg/vm/lib/transformations/type_flow/analysis.dart

@@ -191,17 +191,12 @@ class _DirectInvocation extends _Invocation {
       case CallKind.PropertyGet:
         assertx(args.values.length == firstParamIndex);
         assertx(args.names.isEmpty);
-        fieldValue.isGetterUsed = true;
         return fieldValue.getValue(
             typeFlowAnalysis, field.isStatic ? null : args.values[0]);
 
       case CallKind.PropertySet:
-      case CallKind.SetFieldInConstructor:
         assertx(args.values.length == firstParamIndex + 1);
         assertx(args.names.isEmpty);
-        if (selector.callKind == CallKind.PropertySet) {
-          fieldValue.isSetterUsed = true;
-        }
         final Type setterArg = args.values[firstParamIndex];
         fieldValue.setValue(
             setterArg, typeFlowAnalysis, field.isStatic ? null : args.receiver);
@@ -211,7 +206,6 @@ class _DirectInvocation extends _Invocation {
         // Call via field.
         // TODO(alexmarkov): support function types and use inferred type
         // to get more precise return type.
-        fieldValue.isGetterUsed = true;
         final receiver = fieldValue.getValue(
             typeFlowAnalysis, field.isStatic ? null : args.values[0]);
         if (receiver != const EmptyType()) {
@@ -778,12 +772,6 @@ class _FieldValue extends _DependencyTracker {
   /// Flag indicating if field initializer was executed.
   bool isInitialized = false;
 
-  /// Flag indicating if field getter was executed.
-  bool isGetterUsed = false;
-
-  /// Flag indicating if field setter was executed.
-  bool isSetterUsed = false;
-
   _FieldValue(this.field, this.typeGuardSummary, TypesBuilder typesBuilder)
       : staticType = typesBuilder.fromStaticType(field.type, true) {
     if (field.initializer == null && _isDefaultValueOfFieldObservable()) {
@@ -1403,26 +1391,6 @@ class TypeFlowAnalysis implements EntryPointsListener, CallHandler {
     return false;
   }
 
-  /// Returns true if analysis found that getter corresponding to the given
-  /// [field] could be executed.
-  bool isFieldGetterUsed(Field field) {
-    final fieldValue = _fieldValues[field];
-    if (fieldValue != null) {
-      return fieldValue.isGetterUsed;
-    }
-    return false;
-  }
-
-  /// Returns true if analysis found that setter corresponding to the given
-  /// [field] could be executed.
-  bool isFieldSetterUsed(Field field) {
-    final fieldValue = _fieldValues[field];
-    if (fieldValue != null) {
-      return fieldValue.isSetterUsed;
-    }
-    return false;
-  }
-
   bool isClassAllocated(Class c) => hierarchyCache.allocatedClasses.contains(c);
 
   Call callSite(TreeNode node) => summaryCollector.callSites[node];

pkg/vm/lib/transformations/type_flow/calls.dart

@@ -16,8 +16,7 @@ enum CallKind {
   Method, // x.foo(..) or foo()
   PropertyGet, // ... x.foo ...
   PropertySet, // x.foo = ...
-  FieldInitializer, // run initializer of a field
-  SetFieldInConstructor, // foo = ... in initializer list in a constructor
+  FieldInitializer,
 }
 
 /// [Selector] encapsulates the way of calling (at the call site).
@@ -56,7 +55,6 @@ abstract class Selector {
         return member.getterType;
       case CallKind.PropertySet:
       case CallKind.FieldInitializer:
-      case CallKind.SetFieldInConstructor:
         return const BottomType();
     }
     return null;
@@ -74,8 +72,7 @@ abstract class Selector {
       case CallKind.PropertySet:
         return (member is Field) || ((member is Procedure) && member.isSetter);
       case CallKind.FieldInitializer:
-      case CallKind.SetFieldInConstructor:
-        return member is Field;
+        return (member is Field);
     }
     return false;
   }
@@ -87,7 +84,6 @@ abstract class Selector {
       case CallKind.PropertyGet:
         return 'get ';
       case CallKind.PropertySet:
-      case CallKind.SetFieldInConstructor:
         return 'set ';
       case CallKind.FieldInitializer:
         return 'init ';

pkg/vm/lib/transformations/type_flow/summary_collector.dart

@@ -800,7 +800,6 @@ class SummaryCollector extends RecursiveVisitor<TypeExpr> {
         break;
 
       case CallKind.PropertySet:
-      case CallKind.SetFieldInConstructor:
         args.add(new Type.nullableAny());
         break;
 
@@ -2072,11 +2071,8 @@ class SummaryCollector extends RecursiveVisitor<TypeExpr> {
   TypeExpr visitFieldInitializer(FieldInitializer node) {
     final value = _visit(node.value);
     final args = new Args<TypeExpr>([_receiver, value]);
-    _makeCall(
-        node,
-        new DirectSelector(node.field,
-            callKind: CallKind.SetFieldInConstructor),
-        args);
+    _makeCall(node,
+        new DirectSelector(node.field, callKind: CallKind.PropertySet), args);
     return null;
   }