Introduce HLocalValue and HLocalGet/Set.

lib/compiler/implementation/ssa/codegen.dart

 // Copyright (c) 2012, 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.
 
 class SsaCodeGeneratorTask extends CompilerTask {
   final JavaScriptBackend backend;
   SsaCodeGeneratorTask(JavaScriptBackend backend)
       : this.backend = backend,
         super(backend.compiler);
   String get name() => 'SSA code generator';
@@ skipping 1697 matching lines @@
             compiler.namer.setterName(currentLibrary, superMethod.name);
       }
       buffer.add('$className.prototype.$methodName.call');
       visitArguments(node.inputs);
     }
     endExpression(JSPrecedence.CALL_PRECEDENCE);
     world.registerStaticUse(superMethod);
   }
 
   visitFieldGet(HFieldGet node) {
-    if (!node.isFromActivation()) {
-      String name = compiler.namer.getName(node.element);
-      beginExpression(JSPrecedence.MEMBER_PRECEDENCE);
-      use(node.receiver, JSPrecedence.MEMBER_PRECEDENCE);
-      buffer.add('.');
-      buffer.add(name);
-      beginExpression(JSPrecedence.MEMBER_PRECEDENCE);
-      Type type = node.receiver.propagatedType.computeType(compiler);
-      if (type != null) {
-        world.registerFieldGetter(node.element.name, type);
-      }
-    } else {
-      use(node.receiver, JSPrecedence.EXPRESSION_PRECEDENCE);
+    String name = compiler.namer.getName(node.element);
+    beginExpression(JSPrecedence.MEMBER_PRECEDENCE);
+    use(node.receiver, JSPrecedence.MEMBER_PRECEDENCE);
+    buffer.add('.');
+    buffer.add(name);
+    beginExpression(JSPrecedence.MEMBER_PRECEDENCE);
+    Type type = node.receiver.propagatedType.computeType(compiler);
+    if (type != null) {
+      world.registerFieldGetter(node.element.name, type);
     }
   }
 
   visitFieldSet(HFieldSet node) {
-    String name;
-    if (!node.isFromActivation()) {
-      name = compiler.namer.getName(node.element);
-      beginExpression(JSPrecedence.ASSIGNMENT_PRECEDENCE);
-      use(node.receiver, JSPrecedence.MEMBER_PRECEDENCE);
-      buffer.add('.');
-      buffer.add(name);
-      Type type = node.receiver.propagatedType.computeType(compiler);
-      if (type != null) {
-        world.registerFieldSetter(node.element.name, type);
-      }
-    } else {
-      declareInstruction(node.receiver);
+    String name = compiler.namer.getName(node.element);
+    beginExpression(JSPrecedence.ASSIGNMENT_PRECEDENCE);
+    use(node.receiver, JSPrecedence.MEMBER_PRECEDENCE);
+    buffer.add('.');
+    buffer.add(name);
+    Type type = node.receiver.propagatedType.computeType(compiler);
+    if (type != null) {
+      world.registerFieldSetter(node.element.name, type);
     }
     buffer.add(' = ');
     use(node.value, JSPrecedence.ASSIGNMENT_PRECEDENCE);
-    if (node.receiver !== null) {
-      endExpression(JSPrecedence.ASSIGNMENT_PRECEDENCE);
-    }
+    endExpression(JSPrecedence.ASSIGNMENT_PRECEDENCE);
+  }
+
+  visitLocalGet(HLocalGet node) {
+    use(node.receiver, JSPrecedence.EXPRESSION_PRECEDENCE);
+  }
+
+  visitLocalSet(HLocalSet node) {
+    declareInstruction(node.receiver);
+    buffer.add(' = ');
+    use(node.value, JSPrecedence.ASSIGNMENT_PRECEDENCE);
   }
 
   visitForeign(HForeign node) {
     String code = node.code.slowToString();
     List<HInstruction> inputs = node.inputs;
     List<String> parts = code.split('#');
     if (parts.length != inputs.length + 1) {
       compiler.internalError(
           'Wrong number of arguments for JS', instruction: node);
     }
@@ skipping 127 matching lines @@
       visitInvokeBinary(input,
                         inverseOperator[relational.operation.name.stringValue]);
     } else {
       beginExpression(JSPrecedence.PREFIX_PRECEDENCE);
       buffer.add('!');
       use(input, JSPrecedence.PREFIX_PRECEDENCE);
       endExpression(JSPrecedence.PREFIX_PRECEDENCE);
     }
   }
 
-  visitParameterValue(HParameterValue node) {
+  visitParameterValue(HParameterValue node) => visitLocalValue(node);
+
+  visitLocalValue(HLocalValue node) {
     assert(isGenerateAtUseSite(node));
     buffer.add(variableNames.getName(node));
   }
 
   visitPhi(HPhi node) {
     // This method is only called for phis that are generated at use
     // site. A phi can be generated at use site only if it is the
     // result of a control flow operation.
     HBasicBlock ifBlock = node.block.dominator;
     assert(controlFlowOperators.contains(ifBlock.last));
@@ skipping 983 matching lines @@
       startBailoutSwitch();
     }
   }
 
   void endLabeledBlock(HLabeledBlockInformation labeledBlockInfo) {
     if (labeledBlockInfo.body.start.hasGuards()) {
       endBailoutSwitch();
     }
   }
 }