Move remaining helpers to BackendHelpers

pkg/compiler/lib/src/ssa/interceptor_simplifier.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of ssa;
 
 /**
  * This phase simplifies interceptors in multiple ways:
  *
  * 1) If the interceptor is for an object whose type is known, it
@@ skipping 16 matching lines @@
 class SsaSimplifyInterceptors extends HBaseVisitor
     implements OptimizationPhase {
   final String name = "SsaSimplifyInterceptors";
   final ConstantSystem constantSystem;
   final Compiler compiler;
   final CodegenWorkItem work;
   HGraph graph;
 
   SsaSimplifyInterceptors(this.compiler, this.constantSystem, this.work);
 
+  JavaScriptBackend get backend => compiler.backend;
+
+  BackendHelpers get helpers => backend.helpers;
+
+  ClassWorld get classWorld => compiler.world;
+
   void visitGraph(HGraph graph) {
     this.graph = graph;
     visitDominatorTree(graph);
   }
 
   void visitBasicBlock(HBasicBlock node) {
     currentBlock = node;
 
     HInstruction instruction = node.first;
     while (instruction != null) {
@@ skipping 26 matching lines @@
     HInstruction constant = tryComputeConstantInterceptor(
         invoke.inputs[1], interceptor.interceptedClasses);
     if (constant != null) {
       invoke.changeUse(interceptor, constant);
     }
     return false;
   }
 
   bool canUseSelfForInterceptor(HInstruction receiver,
                                 Set<ClassElement> interceptedClasses) {
-    JavaScriptBackend backend = compiler.backend;
-    ClassWorld classWorld = compiler.world;
 
     if (receiver.canBePrimitive(compiler)) {
       // Primitives always need interceptors.
       return false;
     }
     if (receiver.canBeNull() &&
-        interceptedClasses.contains(backend.jsNullClass)) {
+        interceptedClasses.contains(helpers.jsNullClass)) {
       // Need the JSNull interceptor.
       return false;
     }
 
     // All intercepted classes extend `Interceptor`, so if the receiver can't be
     // a class extending `Interceptor` then it can be called directly.
-    return new TypeMask.nonNullSubclass(backend.jsInterceptorClass, classWorld)
+    return new TypeMask.nonNullSubclass(helpers.jsInterceptorClass, classWorld)
         .intersection(receiver.instructionType, classWorld)
         .isEmpty;
   }
 
   HInstruction tryComputeConstantInterceptor(
       HInstruction input,
       Set<ClassElement> interceptedClasses) {
     if (input == graph.explicitReceiverParameter) {
       // If `explicitReceiverParameter` is set it means the current method is an
       // interceptor method, and `this` is the interceptor.  The caller just did
@@ skipping 15 matching lines @@
 
     ConstantValue constant =
         new InterceptorConstantValue(constantInterceptor.thisType);
     return graph.addConstant(constant, compiler);
   }
 
   ClassElement tryComputeConstantInterceptorFromType(
       TypeMask type,
       Set<ClassElement> interceptedClasses) {
 
-    ClassWorld classWorld = compiler.world;
-    JavaScriptBackend backend = compiler.backend;
     if (type.isNullable) {
       if (type.isEmpty) {
-        return backend.jsNullClass;
+        return helpers.jsNullClass;
       }
     } else if (type.containsOnlyInt(classWorld)) {
-      return backend.jsIntClass;
+      return helpers.jsIntClass;
     } else if (type.containsOnlyDouble(classWorld)) {
-      return backend.jsDoubleClass;
+      return helpers.jsDoubleClass;
     } else if (type.containsOnlyBool(classWorld)) {
-      return backend.jsBoolClass;
+      return helpers.jsBoolClass;
     } else if (type.containsOnlyString(classWorld)) {
-      return backend.jsStringClass;
-    } else if (type.satisfies(backend.jsArrayClass, classWorld)) {
-      return backend.jsArrayClass;
+      return helpers.jsStringClass;
+    } else if (type.satisfies(helpers.jsArrayClass, classWorld)) {
+      return helpers.jsArrayClass;
     } else if (type.containsOnlyNum(classWorld) &&
-        !interceptedClasses.contains(backend.jsIntClass) &&
-        !interceptedClasses.contains(backend.jsDoubleClass)) {
+        !interceptedClasses.contains(helpers.jsIntClass) &&
+        !interceptedClasses.contains(helpers.jsDoubleClass)) {
       // If the method being intercepted is not defined in [int] or [double] we
       // can safely use the number interceptor.  This is because none of the
       // [int] or [double] methods are called from a method defined on [num].
-      return backend.jsNumberClass;
+      return helpers.jsNumberClass;
     } else {
       // Try to find constant interceptor for a native class.  If the receiver
       // is constrained to a leaf native class, we can use the class's
       // interceptor directly.
 
       // TODO(sra): Key DOM classes like Node, Element and Event are not leaf
       // classes.  When the receiver type is not a leaf class, we might still be
       // able to use the receiver class as a constant interceptor.  It is
       // usually the case that methods defined on a non-leaf class don't test
       // for a subclass or call methods defined on a subclass.  Provided the
@@ skipping 35 matching lines @@
     //
     // Currently we use the most general interceptor since all intercepted types
     // implement `hashCode`. But in this example, `a.hashCode` is only reached
     // if `a.length` succeeds, which is indicated by the hashCode receiver being
     // a HTypeKnown instruction.
 
     int useCount(HInstruction user, HInstruction used) =>
         user.inputs.where((input) => input == used).length;
 
     Set<ClassElement> interceptedClasses;
-    JavaScriptBackend backend = compiler.backend;
     HInstruction dominator = findDominator(node.usedBy);
     // If there is a call that dominates all other uses, we can use just the
     // selector of that instruction.
     if (dominator is HInvokeDynamic &&
         dominator.isCallOnInterceptor(compiler) &&
         node == dominator.receiver &&
         useCount(dominator, node) == 1) {
       interceptedClasses =
             backend.getInterceptedClassesOn(dominator.selector.name);
 
       // If we found that we need number, we must still go through all
       // uses to check if they require int, or double.
-      if (interceptedClasses.contains(backend.jsNumberClass) &&
-          !(interceptedClasses.contains(backend.jsDoubleClass) ||
-            interceptedClasses.contains(backend.jsIntClass))) {
+      if (interceptedClasses.contains(helpers.jsNumberClass) &&
+          !(interceptedClasses.contains(helpers.jsDoubleClass) ||
+            interceptedClasses.contains(helpers.jsIntClass))) {
         for (HInstruction user in node.usedBy) {
           if (user is! HInvoke) continue;
           Set<ClassElement> intercepted =
               backend.getInterceptedClassesOn(user.selector.name);
-          if (intercepted.contains(backend.jsIntClass)) {
-            interceptedClasses.add(backend.jsIntClass);
+          if (intercepted.contains(helpers.jsIntClass)) {
+            interceptedClasses.add(helpers.jsIntClass);
           }
-          if (intercepted.contains(backend.jsDoubleClass)) {
-            interceptedClasses.add(backend.jsDoubleClass);
+          if (intercepted.contains(helpers.jsDoubleClass)) {
+            interceptedClasses.add(helpers.jsDoubleClass);
           }
         }
       }
     } else {
       interceptedClasses = new Set<ClassElement>();
       for (HInstruction user in node.usedBy) {
         if (user is HInvokeDynamic &&
             user.isCallOnInterceptor(compiler) &&
             node == user.receiver &&
             useCount(user, node) == 1) {
@@ skipping 37 matching lines @@
       node.block.rewrite(node, constantInterceptor);
       return false;
     }
 
     // Do we have an 'almost constant' interceptor?  The receiver could be
     // `null` but not any other JavaScript falsy value, `null` values cause
     // `NoSuchMethodError`s, and if the receiver was not null we would have a
     // constant interceptor `C`.  Then we can use `(receiver && C)` for the
     // interceptor.
     if (receiver.canBeNull() && !node.isConditionalConstantInterceptor) {
-      if (!interceptedClasses.contains(backend.jsNullClass)) {
+      if (!interceptedClasses.contains(helpers.jsNullClass)) {
         // Can use `(receiver && C)` only if receiver is either null or truthy.
         if (!(receiver.canBePrimitiveNumber(compiler) ||
             receiver.canBePrimitiveBoolean(compiler) ||
             receiver.canBePrimitiveString(compiler))) {
           ClassElement interceptorClass = tryComputeConstantInterceptorFromType(
               receiver.instructionType.nonNullable(), interceptedClasses);
           if (interceptorClass != null) {
             HInstruction constantInstruction =
                 graph.addConstant(
                     new InterceptorConstantValue(interceptorClass.thisType),
@@ skipping 19 matching lines @@
       block.addAfter(user, replacement);
       block.rewrite(user, replacement);
       block.remove(user);
       return false;
     }
 
     if (user is HIs) {
       // See if we can rewrite the is-check to use 'instanceof', i.e. rewrite
       // "getInterceptor(x).$isT" to "x instanceof T".
       if (node == user.interceptor) {
-        JavaScriptBackend backend = compiler.backend;
         if (backend.mayGenerateInstanceofCheck(user.typeExpression)) {
           HInstruction instanceofCheck = new HIs.instanceOf(
               user.typeExpression, user.expression, user.instructionType);
           instanceofCheck.sourceInformation = user.sourceInformation;
           instanceofCheck.sourceElement = user.sourceElement;
           return replaceUserWith(instanceofCheck);
         }
       }
     } else if (user is HInvokeDynamic) {
       if (node == user.inputs[0]) {
@@ skipping 58 matching lines @@
       instruction = new HInvokeDynamicMethod(
           selector, mask, inputs, node.instructionType, true);
     }
 
     HBasicBlock block = node.block;
     block.addAfter(node, instruction);
     block.rewrite(node, instruction);
     return true;
   }
 }