dart2js: Constant folding and specialization for remainder

pkg/compiler/lib/src/js_backend/constant_system_javascript.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.
 
 library dart2js.constant_system.js;
 
 import '../compiler.dart' show Compiler;
 import '../constant_system_dart.dart';
 import '../constants/constant_system.dart';
 import '../constants/values.dart';
@@ skipping 106 matching lines @@
     ConstantValue result = _addOperation.fold(left, right);
     if (result != null && result.isNum) {
       return JAVA_SCRIPT_CONSTANT_SYSTEM.convertToJavaScriptConstant(result);
     }
     return result;
   }
 
   apply(left, right) => _addOperation.apply(left, right);
 }
 
+class JavaScriptRemainderOperation extends ArithmeticNumOperation {
+  String get name => 'remainder';
+
+  const JavaScriptRemainderOperation();
+
+  int foldInts(int left, int right) {
+    if (right == 0) return null;
+    return left.remainder(right);
+  }
+
+  num foldNums(num left, num right) => left.remainder(right);
+  apply(left, right) => left.remainder(right);
+}
+
 class JavaScriptBinaryArithmeticOperation implements BinaryOperation {
   final BinaryOperation dartArithmeticOperation;
 
   const JavaScriptBinaryArithmeticOperation(this.dartArithmeticOperation);
 
   String get name => dartArithmeticOperation.name;
 
   ConstantValue fold(ConstantValue left, ConstantValue right) {
     ConstantValue result = dartArithmeticOperation.fold(left, right);
     if (result == null) return result;
@@ skipping 89 matching lines @@
   final identity = const JavaScriptIdentityOperation();
   final ifNull = const IfNullOperation();
   final lessEqual = const LessEqualOperation();
   final less = const LessOperation();
   final modulo =
       const JavaScriptBinaryArithmeticOperation(const ModuloOperation());
   final multiply =
       const JavaScriptBinaryArithmeticOperation(const MultiplyOperation());
   final negate = const JavaScriptNegateOperation();
   final not = const NotOperation();
+  final remainder = const JavaScriptRemainderOperation();
   final shiftLeft =
       const JavaScriptBinaryBitOperation(const ShiftLeftOperation());
   final shiftRight = const JavaScriptShiftRightOperation();
   final subtract =
       const JavaScriptBinaryArithmeticOperation(const SubtractOperation());
   final truncatingDivide = const JavaScriptBinaryArithmeticOperation(
       const TruncatingDivideOperation());
   final codeUnitAt = const CodeUnitAtRuntimeOperation();
   final round = const JavaScriptRoundOperation();
 
@@ skipping 193 matching lines @@
       result.add(keyList);
     } else {
       // Add the keys individually to avoid generating an unused list constant
       // for the keys.
       result.addAll(keys);
     }
     result.addAll(values);
     return result;
   }
 }