1 /*
2  * [The "BSD license"]
3  * Copyright (c) 2011 Terence Parr
4  * All rights reserved.
5  *
6  * Conversion to C#:
7  * Copyright (c) 2011 Sam Harwell, Pixel Mine, Inc.
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 namespace Antlr3.Runtime.Test.BuildOptions
34 {
35     using System.Collections.Generic;
36     using Antlr.Runtime.Tree;
37 
38     using BigInteger = System.Numerics.BigInteger;
39     using Console = System.Console;
40 
41     partial class DebugTreeGrammar
42     {
43         /** Points to functions tracked by tree builder. */
44         private List<CommonTree> functionDefinitions;
45 
46         /** Remember local variables. Currently, this is only the function parameter.
47          */
48         private readonly IDictionary<string, BigInteger> localMemory = new Dictionary<string, BigInteger>();
49 
50         /** Remember global variables set by =. */
51         private IDictionary<string, BigInteger> globalMemory = new Dictionary<string, BigInteger>();
52 
53         /** Set up an evaluator with a node stream; and a set of function definition ASTs. */
DebugTreeGrammar(CommonTreeNodeStream nodes, List<CommonTree> functionDefinitions)54         public DebugTreeGrammar(CommonTreeNodeStream nodes, List<CommonTree> functionDefinitions)
55             : this(nodes)
56         {
57             this.functionDefinitions = functionDefinitions;
58         }
59 
60         /** Set up a local evaluator for a nested function call. The evaluator gets the definition
61          *  tree of the function; the set of all defined functions (to find locally called ones); a
62          *  pointer to the global variable memory; and the value of the function parameter to be
63          *  added to the local memory.
64          */
DebugTreeGrammar(CommonTree function, List<CommonTree> functionDefinitions, IDictionary<string, BigInteger> globalMemory, BigInteger paramValue)65         private DebugTreeGrammar(CommonTree function,
66                      List<CommonTree> functionDefinitions,
67                      IDictionary<string, BigInteger> globalMemory,
68                      BigInteger paramValue)
69             // Expected tree for function: ^(FUNC ID ( INT | ID ) expr)
70             : this(new CommonTreeNodeStream(function.GetChild(2)), functionDefinitions)
71         {
72             this.globalMemory = globalMemory;
73             localMemory[function.GetChild(1).Text] = paramValue;
74         }
75 
76         /** Find matching function definition for a function name and parameter
77          *  value. The first definition is returned where (a) the name matches
78          *  and (b) the formal parameter agrees if it is defined as constant.
79          */
findFunction(string name, BigInteger paramValue)80         private CommonTree findFunction(string name, BigInteger paramValue)
81         {
82             foreach (CommonTree f in functionDefinitions)
83             {
84                 // Expected tree for f: ^(FUNC ID (ID | INT) expr)
85                 if (f.GetChild(0).Text.Equals(name))
86                 {
87                     // Check whether parameter matches
88                     CommonTree formalPar = (CommonTree)f.GetChild(1);
89                     if (formalPar.Token.Type == INT
90                         && !BigInteger.Parse(formalPar.Token.Text).Equals(paramValue))
91                     {
92                         // Constant in formalPar list does not match actual value -> no match.
93                         continue;
94                     }
95                     // Parameter (value for INT formal arg) as well as fct name agrees!
96                     return f;
97                 }
98             }
99             return null;
100         }
101 
102         /** Get value of name up call stack. */
getValue(string name)103         internal BigInteger getValue(string name)
104         {
105             BigInteger value;
106             if (localMemory.TryGetValue(name, out value) && value != null)
107             {
108                 return value;
109             }
110             if (globalMemory.TryGetValue(name, out value) && value != null)
111             {
112                 return value;
113             }
114             // not found in local memory or global memory
115             Console.Error.WriteLine("undefined variable " + name);
116             return BigInteger.Zero;
117         }
118     }
119 }
120