Add JavaScript AST.

lib/compiler/implementation/ssa/codegen_helpers.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.
 
 /**
  * Instead of emitting each SSA instruction with a temporary variable
  * mark instructions that can be emitted at their use-site.
  * For example, in:
  *   t0 = 4;
  *   t1 = 3;
@@ skipping 307 matching lines @@
     }
 
     // If [thenInput] is defined in the first predecessor, then it is only used
     // by [phi] and can be generated at use site.
     if (thenInput.block === end.predecessors[0]) {
       assert(thenInput.usedBy.length == 1);
       markAsGenerateAtUseSite(thenInput);
     }
   }
 }
-
-// Precedence information for JavaScript operators.
-class JSPrecedence {
-   // Used as precedence for something that's not even an expression.
-  static final int STATEMENT_PRECEDENCE      = 0;
-  // Precedences of JS operators.
-  static final int EXPRESSION_PRECEDENCE     = 1;
-  static final int ASSIGNMENT_PRECEDENCE     = 2;
-  static final int CONDITIONAL_PRECEDENCE    = 3;
-  static final int LOGICAL_OR_PRECEDENCE     = 4;
-  static final int LOGICAL_AND_PRECEDENCE    = 5;
-  static final int BITWISE_OR_PRECEDENCE     = 6;
-  static final int BITWISE_XOR_PRECEDENCE    = 7;
-  static final int BITWISE_AND_PRECEDENCE    = 8;
-  static final int EQUALITY_PRECEDENCE       = 9;
-  static final int RELATIONAL_PRECEDENCE     = 10;
-  static final int SHIFT_PRECEDENCE          = 11;
-  static final int ADDITIVE_PRECEDENCE       = 12;
-  static final int MULTIPLICATIVE_PRECEDENCE = 13;
-  static final int PREFIX_PRECEDENCE         = 14;
-  static final int POSTFIX_PRECEDENCE        = 15;
-  static final int CALL_PRECEDENCE           = 16;
-  // We never use "new MemberExpression" without arguments, so we can
-  // combine CallExpression and MemberExpression without ambiguity.
-  static final int MEMBER_PRECEDENCE         = CALL_PRECEDENCE;
-  static final int PRIMARY_PRECEDENCE        = 17;
-
-  // The operators that an occur in HBinaryOp.
-  static final Map<String, JSBinaryOperatorPrecedence> binary = const {
-    "||" : const JSBinaryOperatorPrecedence(LOGICAL_OR_PRECEDENCE,
-                                            LOGICAL_AND_PRECEDENCE),
-    "&&" : const JSBinaryOperatorPrecedence(LOGICAL_AND_PRECEDENCE,
-                                            BITWISE_OR_PRECEDENCE),
-    "|" : const JSBinaryOperatorPrecedence(BITWISE_OR_PRECEDENCE,
-                                           BITWISE_XOR_PRECEDENCE),
-    "^" : const JSBinaryOperatorPrecedence(BITWISE_XOR_PRECEDENCE,
-                                           BITWISE_AND_PRECEDENCE),
-    "&" : const JSBinaryOperatorPrecedence(BITWISE_AND_PRECEDENCE,
-                                           EQUALITY_PRECEDENCE),
-    "==" : const JSBinaryOperatorPrecedence(EQUALITY_PRECEDENCE,
-                                            RELATIONAL_PRECEDENCE),
-    "!=" : const JSBinaryOperatorPrecedence(EQUALITY_PRECEDENCE,
-                                            RELATIONAL_PRECEDENCE),
-    "===" : const JSBinaryOperatorPrecedence(EQUALITY_PRECEDENCE,
-                                             RELATIONAL_PRECEDENCE),
-    "!==" : const JSBinaryOperatorPrecedence(EQUALITY_PRECEDENCE,
-                                             RELATIONAL_PRECEDENCE),
-    "<" : const JSBinaryOperatorPrecedence(RELATIONAL_PRECEDENCE,
-                                           SHIFT_PRECEDENCE),
-    ">" : const JSBinaryOperatorPrecedence(RELATIONAL_PRECEDENCE,
-                                           SHIFT_PRECEDENCE),
-    "<=" : const JSBinaryOperatorPrecedence(RELATIONAL_PRECEDENCE,
-                                            SHIFT_PRECEDENCE),
-    ">=" : const JSBinaryOperatorPrecedence(RELATIONAL_PRECEDENCE,
-                                            SHIFT_PRECEDENCE),
-    "<<" : const JSBinaryOperatorPrecedence(SHIFT_PRECEDENCE,
-                                            ADDITIVE_PRECEDENCE),
-    ">>" : const JSBinaryOperatorPrecedence(SHIFT_PRECEDENCE,
-                                            ADDITIVE_PRECEDENCE),
-    ">>>" : const JSBinaryOperatorPrecedence(SHIFT_PRECEDENCE,
-                                             ADDITIVE_PRECEDENCE),
-    "+" : const JSBinaryOperatorPrecedence(ADDITIVE_PRECEDENCE,
-                                           MULTIPLICATIVE_PRECEDENCE),
-    "-" : const JSBinaryOperatorPrecedence(ADDITIVE_PRECEDENCE,
-                                           MULTIPLICATIVE_PRECEDENCE),
-    "*" : const JSBinaryOperatorPrecedence(MULTIPLICATIVE_PRECEDENCE,
-                                           PREFIX_PRECEDENCE),
-    "/" : const JSBinaryOperatorPrecedence(MULTIPLICATIVE_PRECEDENCE,
-                                           PREFIX_PRECEDENCE),
-    "%" : const JSBinaryOperatorPrecedence(MULTIPLICATIVE_PRECEDENCE,
-                                           PREFIX_PRECEDENCE),
-  };
-}
-
-class JSBinaryOperatorPrecedence {
-  final int left;
-  final int right;
-  const JSBinaryOperatorPrecedence(this.left, this.right);
-  // All binary operators (excluding assignment) are left associative.
-  int get precedence() => left;
-}