dart2js: Rename emitters.

pkg/compiler/lib/src/js_emitter/old_emitter/nsm_emitter.dart

Index: pkg/compiler/lib/src/js_emitter/old_emitter/nsm_emitter.dart
diff --git a/pkg/compiler/lib/src/js_emitter/old_emitter/nsm_emitter.dart b/pkg/compiler/lib/src/js_emitter/old_emitter/nsm_emitter.dart
deleted file mode 100644
index 5d7df35210e3da68bf1c1c7cc827ea5f54809393..0000000000000000000000000000000000000000
--- a/pkg/compiler/lib/src/js_emitter/old_emitter/nsm_emitter.dart
+++ /dev/null
@@ -1,391 +0,0 @@
-// 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 dart2js.js_emitter;
-
-class NsmEmitter extends CodeEmitterHelper {
-  final List<Selector> trivialNsmHandlers = <Selector>[];
-
-  /// If this is true then we can generate the noSuchMethod handlers at startup
-  /// time, instead of them being emitted as part of the Object class.
-  bool get generateTrivialNsmHandlers => true;
-
-  // If we need fewer than this many noSuchMethod handlers we can save space by
-  // just emitting them in JS, rather than emitting the JS needed to generate
-  // them at run time.
-  static const VERY_FEW_NO_SUCH_METHOD_HANDLERS = 10;
-
-  static const MAX_MINIFIED_LENGTH_FOR_DIFF_ENCODING = 4;
-
-  void emitNoSuchMethodHandlers(AddPropertyFunction addProperty) {
-
-    ClassStubGenerator generator =
-        new ClassStubGenerator(compiler, namer, backend);
-
-    // Keep track of the JavaScript names we've already added so we
-    // do not introduce duplicates (bad for code size).
-    Map<jsAst.Name, Selector> addedJsNames
-        = generator.computeSelectorsForNsmHandlers();
-
-    // Set flag used by generateMethod helper below.  If we have very few
-    // handlers we use addProperty for them all, rather than try to generate
-    // them at runtime.
-    bool haveVeryFewNoSuchMemberHandlers =
-        (addedJsNames.length < VERY_FEW_NO_SUCH_METHOD_HANDLERS);
-    List<jsAst.Name> names = addedJsNames.keys.toList()
-        ..sort();
-    for (jsAst.Name jsName in names) {
-      Selector selector = addedJsNames[jsName];
-      String reflectionName = emitter.getReflectionName(selector, jsName);
-
-      if (reflectionName != null) {
-        emitter.mangledFieldNames[jsName] = reflectionName;
-      }
-
-      List<jsAst.Expression> argNames =
-          selector.callStructure.getOrderedNamedArguments().map((String name) =>
-              js.string(name)).toList();
-      int type = selector.invocationMirrorKind;
-      if (!haveVeryFewNoSuchMemberHandlers &&
-          isTrivialNsmHandler(type, argNames, selector, jsName) &&
-          reflectionName == null) {
-        trivialNsmHandlers.add(selector);
-      } else {
-        StubMethod method =
-            generator.generateStubForNoSuchMethod(jsName, selector);
-        addProperty(method.name, method.code);
-        if (reflectionName != null) {
-          bool accessible =
-              compiler.world.allFunctions.filter(selector, null).any(
-              (Element e) => backend.isAccessibleByReflection(e));
-          addProperty(namer.asName('+$reflectionName'),
-                      js(accessible ? '2' : '0'));
-        }
-      }
-    }
-  }
-
-  // Identify the noSuchMethod handlers that are so simple that we can
-  // generate them programatically.
-  bool isTrivialNsmHandler(
-      int type, List argNames, Selector selector, jsAst.Name internalName) {
-    if (!generateTrivialNsmHandlers) return false;
-    // Check for named arguments.
-    if (argNames.length != 0) return false;
-    // Check for unexpected name (this doesn't really happen).
-    if (internalName is GetterName) return type == 1;
-    if (internalName is SetterName) return type == 2;
-    return type == 0;
-  }
-
-  /**
-   * Adds (at runtime) the handlers to the Object class which catch calls to
-   * methods that the object does not have.  The handlers create an invocation
-   * mirror object.
-   *
-   * The current version only gives you the minified name when minifying (when
-   * not minifying this method is not called).
-   *
-   * In order to generate the noSuchMethod handlers we only need the minified
-   * name of the method.  We test the first character of the minified name to
-   * determine if it is a getter or a setter, and we use the arguments array at
-   * runtime to get the number of arguments and their values.  If the method
-   * involves named arguments etc. then we don't handle it here, but emit the
-   * handler method directly on the Object class.
-   *
-   * The minified names are mostly 1-4 character names, which we emit in sorted
-   * order (primary key is length, secondary ordering is lexicographic).  This
-   * gives an order like ... dD dI dX da ...
-   *
-   * Gzip is good with repeated text, but it can't diff-encode, so we do that
-   * for it.  We encode the minified names in a comma-separated string, but all
-   * the 1-4 character names are encoded before the first comma as a series of
-   * base 26 numbers.  The last digit of each number is lower case, the others
-   * are upper case, so 1 is "b" and 26 is "Ba".
-   *
-   * We think of the minified names as base 88 numbers using the ASCII
-   * characters from # to z.  The base 26 numbers each encode the delta from
-   * the previous minified name to the next.  So if there is a minified name
-   * called Df and the next is Dh, then they are 2971 and 2973 when thought of
-   * as base 88 numbers.  The difference is 2, which is "c" in lower-case-
-   * terminated base 26.
-   *
-   * The reason we don't encode long minified names with this method is that
-   * decoding the base 88 numbers would overflow JavaScript's puny integers.
-   *
-   * There are some selectors that have a special calling convention (because
-   * they are called with the receiver as the first argument).  They need a
-   * slightly different noSuchMethod handler, so we handle these first.
-   */
-  List<jsAst.Statement> buildTrivialNsmHandlers() {
-    List<jsAst.Statement> statements = <jsAst.Statement>[];
-    if (trivialNsmHandlers.length == 0) return statements;
-
-    bool minify = compiler.enableMinification;
-    bool useDiffEncoding = minify && trivialNsmHandlers.length > 30;
-
-    // Find out how many selectors there are with the special calling
-    // convention.
-    Iterable<Selector> interceptedSelectors = trivialNsmHandlers.where(
-            (Selector s) => backend.isInterceptedName(s.name));
-    Iterable<Selector> ordinarySelectors = trivialNsmHandlers.where(
-            (Selector s) => !backend.isInterceptedName(s.name));
-
-    // Get the short names (JS names, perhaps minified).
-    Iterable<jsAst.Name> interceptedShorts =
-        interceptedSelectors.map(namer.invocationMirrorInternalName);
-    Iterable<jsAst.Name> ordinaryShorts =
-        ordinarySelectors.map(namer.invocationMirrorInternalName);
-
-    jsAst.Expression sortedShorts;
-    Iterable<String> sortedLongs;
-    if (useDiffEncoding) {
-      assert(minify);
-      sortedShorts = new _DiffEncodedListOfNames(
-          [interceptedShorts, ordinaryShorts]);
-    } else {
-      Iterable<Selector> sorted =
-          [interceptedSelectors, ordinarySelectors].expand((e) => (e));
-      sortedShorts = js.concatenateStrings(
-          js.joinLiterals(
-              sorted.map(namer.invocationMirrorInternalName),
-              js.stringPart(",")),
-          addQuotes: true);
-
-      if (!minify) {
-        sortedLongs = sorted.map((selector) =>
-            selector.invocationMirrorMemberName);
-      }
-    }
-    // Startup code that loops over the method names and puts handlers on the
-    // Object class to catch noSuchMethod invocations.
-    ClassElement objectClass = compiler.objectClass;
-    jsAst.Expression createInvocationMirror = backend.emitter
-        .staticFunctionAccess(backend.getCreateInvocationMirror());
-    if (useDiffEncoding) {
-      statements.add(js.statement('''{
-          var objectClassObject = processedClasses.collected[#objectClass],
-              nameSequences = #diffEncoding.split("."),
-              shortNames = [];
-          if (objectClassObject instanceof Array)
-              objectClassObject = objectClassObject[1];
-          for (var j = 0; j < nameSequences.length; ++j) {
-              var sequence = nameSequences[j].split(","),
-                nameNumber = 0;
-            // If we are loading a deferred library the object class will not be
-            // in the collectedClasses so objectClassObject is undefined, and we
-            // skip setting up the names.
-            if (!objectClassObject) break;
-            // Likewise, if the current sequence is empty, we don't process it.
-            if (sequence.length == 0) continue;
-            var diffEncodedString = sequence[0];
-            for (var i = 0; i < diffEncodedString.length; i++) {
-              var codes = [],
-                  diff = 0,
-                  digit = diffEncodedString.charCodeAt(i);
-              for (; digit <= ${$Z};) {
-                diff *= 26;
-                diff += (digit - ${$A});
-                digit = diffEncodedString.charCodeAt(++i);
-              }
-              diff *= 26;
-              diff += (digit - ${$a});
-              nameNumber += diff;
-              for (var remaining = nameNumber;
-                   remaining > 0;
-                   remaining = (remaining / 88) | 0) {
-                codes.unshift(${$HASH} + remaining % 88);
-              }
-              shortNames.push(
-                String.fromCharCode.apply(String, codes));
-            }
-            if (sequence.length > 1) {
-              Array.prototype.push.apply(shortNames, sequence.shift());
-            }
-          }
-        }''', {'objectClass': js.quoteName(namer.className(objectClass)),
-               'diffEncoding': sortedShorts}));
-    } else {
-      // No useDiffEncoding version.
-      statements.add(js.statement(
-          'var objectClassObject = processedClasses.collected[#objectClass],'
-          '    shortNames = #diffEncoding.split(",")',
-          {'objectClass': js.quoteName(namer.className(objectClass)),
-           'diffEncoding': sortedShorts}));
-      if (!minify) {
-        statements.add(js.statement('var longNames = #longs.split(",")',
-                {'longs': js.string(sortedLongs.join(','))}));
-      }
-      statements.add(js.statement(
-          'if (objectClassObject instanceof Array)'
-          '  objectClassObject = objectClassObject[1];'));
-    }
-
-    dynamic isIntercepted =  // jsAst.Expression or bool.
-        interceptedSelectors.isEmpty
-        ? false
-        : ordinarySelectors.isEmpty
-            ? true
-            : js('j < #', js.number(interceptedSelectors.length));
-
-    statements.add(js.statement('''
-      // If we are loading a deferred library the object class will not be in
-      // the collectedClasses so objectClassObject is undefined, and we skip
-      // setting up the names.
-      if (objectClassObject) {
-        for (var j = 0; j < shortNames.length; j++) {
-          var type = 0;
-          var shortName = shortNames[j];
-          if (shortName[0] == "${namer.getterPrefix[0]}") type = 1;
-          if (shortName[0] == "${namer.setterPrefix[0]}") type = 2;
-          // Generate call to:
-          //
-          //     createInvocationMirror(String name, internalName, type,
-          //         arguments, argumentNames)
-          //
-
-          // This 'if' is either a static choice or dynamic choice depending on
-          // [isIntercepted].
-          if (#isIntercepted) {
-            objectClassObject[shortName] =
-                (function(name, shortName, type) {
-                  return function(receiver) {
-                    return this.#noSuchMethodName(
-                      receiver,
-                      #createInvocationMirror(name, shortName, type,
-                          // Create proper Array with all arguments except first
-                          // (receiver).
-                          Array.prototype.slice.call(arguments, 1),
-                          []));
-                  }
-                 })(#names[j], shortName, type);
-          } else {
-            objectClassObject[shortName] =
-                (function(name, shortName, type) {
-                  return function() {
-                    return this.#noSuchMethodName(
-                      // Object.noSuchMethodName ignores the explicit receiver
-                      // argument. We could pass anything in place of [this].
-                      this,
-                      #createInvocationMirror(name, shortName, type,
-                          // Create proper Array with all arguments.
-                          Array.prototype.slice.call(arguments, 0),
-                          []));
-                  }
-                 })(#names[j], shortName, type);
-          }
-        }
-      }''', {
-          'noSuchMethodName': namer.noSuchMethodName,
-          'createInvocationMirror': createInvocationMirror,
-          'names': minify ? 'shortNames' : 'longNames',
-          'isIntercepted': isIntercepted}));
-
-    return statements;
-  }
-}
-
-/// When pretty printed, this node computes a diff-encoded string for the list
-/// of given names.
-///
-/// See [buildTrivialNsmHandlers].
-class _DiffEncodedListOfNames extends jsAst.DeferredString
-                              implements jsAst.AstContainer {
-  String _cachedValue;
-  List<jsAst.ArrayInitializer> ast;
-
-  Iterable<jsAst.Node> get containedNodes => ast;
-
-  _DiffEncodedListOfNames(Iterable<Iterable<jsAst.Name>> names) {
-    // Store the names in ArrayInitializer nodes to make them discoverable
-    // by traversals of the ast.
-    ast = names.map((Iterable i) => new jsAst.ArrayInitializer(i.toList()))
-               .toList();
-  }
-
-  void _computeDiffEncodingForList(Iterable<jsAst.Name> names,
-                                   StringBuffer diffEncoding) {
-    // Treat string as a number in base 88 with digits in ASCII order from # to
-    // z.  The short name sorting is based on length, and uses ASCII order for
-    // equal length strings so this means that names are ascending.  The hash
-    // character, #, is never given as input, but we need it because it's the
-    // implicit leading zero (otherwise we could not code names with leading
-    // dollar signs).
-    int fromBase88(String x) {
-      int answer = 0;
-      for (int i = 0; i < x.length; i++) {
-        int c = x.codeUnitAt(i);
-        // No support for Unicode minified identifiers in JS.
-        assert(c >= $$ && c <= $z);
-        answer *= 88;
-        answer += c - $HASH;
-      }
-      return answer;
-    }
-
-    // Big endian encoding, A = 0, B = 1...
-    // A lower case letter terminates the number.
-    String toBase26(int x) {
-      int c = x;
-      var encodingChars = <int>[];
-      encodingChars.add($a + (c % 26));
-      while (true) {
-        c ~/= 26;
-        if (c == 0) break;
-        encodingChars.add($A + (c % 26));
-      }
-      return new String.fromCharCodes(encodingChars.reversed.toList());
-    }
-
-    // Sort by length, then lexicographic.
-    int compare(String a, String b) {
-      if (a.length != b.length) return a.length - b.length;
-      return a.compareTo(b);
-    }
-
-    List<String> shorts =
-        names.map((jsAst.Name name) => name.name)
-        .toList()
-        ..sort(compare);
-
-    int previous = 0;
-    for (String short in shorts) {
-      if (short.length <= NsmEmitter.MAX_MINIFIED_LENGTH_FOR_DIFF_ENCODING) {
-        int base63 = fromBase88(short);
-        int diff = base63 - previous;
-        previous = base63;
-        String base26Diff = toBase26(diff);
-        diffEncoding.write(base26Diff);
-      } else {
-        if (diffEncoding.length != 0) {
-          diffEncoding.write(',');
-        }
-        diffEncoding.write(short);
-      }
-    }
-  }
-
-  String _computeDiffEncoding() {
-    StringBuffer buffer = new StringBuffer();
-    for (jsAst.ArrayInitializer list in ast) {
-      if (buffer.isNotEmpty) {
-        // Emit period that resets the diff base to zero when we switch to
-        // normal calling convention (this avoids the need to code negative
-        // diffs).
-        buffer.write(".");
-      }
-      List<jsAst.Name> names = list.elements;
-      _computeDiffEncodingForList(names, buffer);
-    }
-    return '"${buffer.toString()}"';
-  }
-
-  String get value {
-    if (_cachedValue == null) {
-      _cachedValue = _computeDiffEncoding();
-    }
-
-    return _cachedValue;
-  }
-}