Move dart2js from sdk/lib/_internal/compiler to pkg/compiler

sdk/lib/_internal/compiler/implementation/js_emitter/old_emitter/nsm_emitter.dart

Index: sdk/lib/_internal/compiler/implementation/js_emitter/old_emitter/nsm_emitter.dart
diff --git a/sdk/lib/_internal/compiler/implementation/js_emitter/old_emitter/nsm_emitter.dart b/sdk/lib/_internal/compiler/implementation/js_emitter/old_emitter/nsm_emitter.dart
deleted file mode 100644
index 36351753178ceaa3a55188d735f60c55d933901e..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/compiler/implementation/js_emitter/old_emitter/nsm_emitter.dart
+++ /dev/null
@@ -1,388 +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) {
-    // Do not generate no such method handlers if there is no class.
-    if (compiler.codegenWorld.directlyInstantiatedClasses.isEmpty) return;
-
-    String noSuchMethodName = namer.publicInstanceMethodNameByArity(
-        Compiler.NO_SUCH_METHOD, Compiler.NO_SUCH_METHOD_ARG_COUNT);
-
-    // Keep track of the JavaScript names we've already added so we
-    // do not introduce duplicates (bad for code size).
-    Map<String, Selector> addedJsNames = new Map<String, Selector>();
-
-    void addNoSuchMethodHandlers(String ignore, Set<Selector> selectors) {
-      // Cache the object class and type.
-      ClassElement objectClass = compiler.objectClass;
-      DartType objectType = objectClass.rawType;
-
-      for (Selector selector in selectors) {
-        TypeMask mask = selector.mask;
-        if (mask == null) {
-          mask = new TypeMask.subclass(compiler.objectClass, compiler.world);
-        }
-
-        if (!mask.needsNoSuchMethodHandling(selector, compiler.world)) continue;
-        String jsName = namer.invocationMirrorInternalName(selector);
-        addedJsNames[jsName] = selector;
-        String reflectionName = emitter.getReflectionName(selector, jsName);
-        if (reflectionName != null) {
-          emitter.mangledFieldNames[jsName] = reflectionName;
-        }
-      }
-    }
-
-    compiler.codegenWorld.invokedNames.forEach(addNoSuchMethodHandlers);
-    compiler.codegenWorld.invokedGetters.forEach(addNoSuchMethodHandlers);
-    compiler.codegenWorld.invokedSetters.forEach(addNoSuchMethodHandlers);
-
-    // 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);
-
-    jsAst.Expression generateMethod(String jsName, Selector selector) {
-      // Values match JSInvocationMirror in js-helper library.
-      int type = selector.invocationMirrorKind;
-      List<String> parameterNames =
-          new List.generate(selector.argumentCount, (i) => '\$$i');
-
-      List<jsAst.Expression> argNames =
-          selector.getOrderedNamedArguments().map((String name) =>
-              js.string(name)).toList();
-
-      String methodName = selector.invocationMirrorMemberName;
-      String internalName = namer.invocationMirrorInternalName(selector);
-      String reflectionName = emitter.getReflectionName(selector, internalName);
-      if (!haveVeryFewNoSuchMemberHandlers &&
-          isTrivialNsmHandler(type, argNames, selector, internalName) &&
-          reflectionName == null) {
-        trivialNsmHandlers.add(selector);
-        return null;
-      }
-
-      assert(backend.isInterceptedName(Compiler.NO_SUCH_METHOD));
-      jsAst.Expression expression = js('this.#(this, #(#, #, #, #, #))', [
-          noSuchMethodName,
-          namer.elementAccess(backend.getCreateInvocationMirror()),
-          js.string(compiler.enableMinification ?
-              internalName : methodName),
-          js.string(internalName),
-          js.number(type),
-          new jsAst.ArrayInitializer.from(parameterNames.map(js)),
-          new jsAst.ArrayInitializer.from(argNames)]);
-
-      if (backend.isInterceptedName(selector.name)) {
-        return js(r'function($receiver, #) { return # }',
-                  [parameterNames, expression]);
-      } else {
-        return js(r'function(#) { return # }', [parameterNames, expression]);
-      }
-    }
-
-    for (String jsName in addedJsNames.keys.toList()..sort()) {
-      Selector selector = addedJsNames[jsName];
-      jsAst.Expression method = generateMethod(jsName, selector);
-      if (method != null) {
-        addProperty(jsName, method);
-        String reflectionName = emitter.getReflectionName(selector, jsName);
-        if (reflectionName != null) {
-          bool accessible = compiler.world.allFunctions.filter(selector).any(
-              (Element e) => backend.isAccessibleByReflection(e));
-          addProperty('+$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, String internalName) {
-    if (!generateTrivialNsmHandlers) return false;
-    // Check for interceptor calling convention.
-    if (backend.isInterceptedName(selector.name)) {
-      // We can handle the calling convention used by intercepted names in the
-      // diff encoding, but we don't use that for non-minified code.
-      if (!compiler.enableMinification) return false;
-      String shortName = namer.invocationMirrorInternalName(selector);
-      if (shortName.length > MAX_MINIFIED_LENGTH_FOR_DIFF_ENCODING) {
-        return false;
-      }
-    }
-    // Check for named arguments.
-    if (argNames.length != 0) return false;
-    // Check for unexpected name (this doesn't really happen).
-    if (internalName.startsWith(namer.getterPrefix[0])) return type == 1;
-    if (internalName.startsWith(namer.setterPrefix[0])) 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;
-    // Sort by calling convention, JS name length and by JS name.
-    trivialNsmHandlers.sort((a, b) {
-      bool aIsIntercepted = backend.isInterceptedName(a.name);
-      bool bIsIntercepted = backend.isInterceptedName(b.name);
-      if (aIsIntercepted != bIsIntercepted) return aIsIntercepted ? -1 : 1;
-      String aName = namer.invocationMirrorInternalName(a);
-      String bName = namer.invocationMirrorInternalName(b);
-      if (aName.length != bName.length) return aName.length - bName.length;
-      return aName.compareTo(bName);
-    });
-
-    // Find out how many selectors there are with the special calling
-    // convention.
-    int firstNormalSelector = trivialNsmHandlers.length;
-    for (int i = 0; i < trivialNsmHandlers.length; i++) {
-      if (!backend.isInterceptedName(trivialNsmHandlers[i].name)) {
-        firstNormalSelector = i;
-        break;
-      }
-    }
-
-    // Get the short names (JS names, perhaps minified).
-    Iterable<String> shorts = trivialNsmHandlers.map((selector) =>
-         namer.invocationMirrorInternalName(selector));
-    final diffShorts = <String>[];
-    var diffEncoding = new StringBuffer();
-
-    // 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());
-    }
-
-    bool minify = compiler.enableMinification;
-    bool useDiffEncoding = minify && shorts.length > 30;
-
-    int previous = 0;
-    int nameCounter = 0;
-    for (String short in shorts) {
-      // Emit period that resets the diff base to zero when we switch to normal
-      // calling convention (this avoids the need to code negative diffs).
-      if (useDiffEncoding && nameCounter == firstNormalSelector) {
-        diffEncoding.write(".");
-        previous = 0;
-      }
-      if (short.length <= MAX_MINIFIED_LENGTH_FOR_DIFF_ENCODING &&
-          useDiffEncoding) {
-        int base63 = fromBase88(short);
-        int diff = base63 - previous;
-        previous = base63;
-        String base26Diff = toBase26(diff);
-        diffEncoding.write(base26Diff);
-      } else {
-        if (useDiffEncoding || diffEncoding.length != 0) {
-          diffEncoding.write(",");
-        }
-        diffEncoding.write(short);
-      }
-      nameCounter++;
-    }
-
-    // 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 = namer.elementAccess(
-        backend.getCreateInvocationMirror());
-    String noSuchMethodName = namer.publicInstanceMethodNameByArity(
-        Compiler.NO_SUCH_METHOD, Compiler.NO_SUCH_METHOD_ARG_COUNT);
-    var type = 0;
-    if (useDiffEncoding) {
-      statements.add(js.statement('''{
-          var objectClassObject =
-                  collectedClasses[#],    // # is name of class Object.
-              shortNames = #.split(","),  // # is diffEncoding.
-              nameNumber = 0,
-              diffEncodedString = shortNames[0],
-              calculatedShortNames = [0, 1];    // 0, 1 are args for splice.
-          // 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) {
-            if (objectClassObject instanceof Array)
-              objectClassObject = objectClassObject[1];
-            for (var i = 0; i < diffEncodedString.length; i++) {
-              var codes = [],
-                  diff = 0,
-                  digit = diffEncodedString.charCodeAt(i);
-              if (digit == ${$PERIOD}) {
-                nameNumber = 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);
-              }
-              calculatedShortNames.push(
-                String.fromCharCode.apply(String, codes));
-            }
-            shortNames.splice.apply(shortNames, calculatedShortNames);
-          }
-        }''', [
-            js.string(namer.getNameOfClass(objectClass)),
-            js.string('$diffEncoding')]));
-    } else {
-      // No useDiffEncoding version.
-      Iterable<String> longs = trivialNsmHandlers.map((selector) =>
-             selector.invocationMirrorMemberName);
-      statements.add(js.statement(
-          'var objectClassObject = collectedClasses[#],'
-          '    shortNames = #.split(",")', [
-              js.string(namer.getNameOfClass(objectClass)),
-              js.string('$diffEncoding')]));
-      if (!minify) {
-        statements.add(js.statement('var longNames = #.split(",")',
-                js.string(longs.join(','))));
-      }
-      statements.add(js.statement(
-          'if (objectClassObject instanceof Array)'
-          '  objectClassObject = objectClassObject[1];'));
-    }
-
-    // TODO(9631): This is no longer valid for native methods.
-    String whatToPatch = emitter.nativeEmitter.handleNoSuchMethod ?
-                         "Object.prototype" :
-                         "objectClassObject";
-
-    List<jsAst.Expression> sliceOffsetArguments =
-        firstNormalSelector == 0
-        ? []
-        : (firstNormalSelector == shorts.length
-            ? [js.number(1)]
-            : [js('(j < #) ? 1 : 0', js.number(firstNormalSelector))]);
-
-    var sliceOffsetParams = sliceOffsetArguments.isEmpty ? [] : ['sliceOffset'];
-
-    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 short = shortNames[j];
-          if (short[0] == "${namer.getterPrefix[0]}") type = 1;
-          if (short[0] == "${namer.setterPrefix[0]}") type = 2;
-          // Generate call to:
-          //
-          //     createInvocationMirror(String name, internalName, type,
-          //         arguments, argumentNames)
-          //
-          $whatToPatch[short] = (function(name, short, type, #) {
-              return function() {
-                return this.#(this,
-                    #(name, short, type,
-                      Array.prototype.slice.call(arguments, #),
-                      []));
-              }
-          })(#[j], short, type, #);
-        }
-      }''', [
-          sliceOffsetParams,  // parameter
-          noSuchMethodName,
-          createInvocationMirror,
-          sliceOffsetParams,  // argument to slice
-          minify ? 'shortNames' : 'longNames',
-          sliceOffsetArguments
-      ]));
-
-    return statements;
-  }
-}