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C-Breeze C Compiler Infrastructure [ Project home page] |
scope_walker.cc
Go to the documentation of this file.00001 // $Id: scope_walker.cc,v 1.3 2003/08/07 23:13:51 pnav Exp $ 00002 // ---------------------------------------------------------------------- 00003 // 00004 // C-Breeze 00005 // C Compiler Framework 00006 // 00007 // Copyright (c) 2000 University of Texas at Austin 00008 // 00009 // Samuel Z. Guyer 00010 // Daniel A. Jimenez 00011 // Calvin Lin 00012 // 00013 // Permission is hereby granted, free of charge, to any person 00014 // obtaining a copy of this software and associated documentation 00015 // files (the "Software"), to deal in the Software without 00016 // restriction, including without limitation the rights to use, copy, 00017 // modify, merge, publish, distribute, sublicense, and/or sell copies 00018 // of the Software, and to permit persons to whom the Software is 00019 // furnished to do so, subject to the following conditions: 00020 // 00021 // The above copyright notice and this permission notice shall be 00022 // included in all copies or substantial portions of the Software. 00023 // 00024 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 00025 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 00026 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 00027 // NONINFRINGEMENT. IN NO EVENT SHALL THE UNIVERSITY OF TEXAS AT 00028 // AUSTIN BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER 00029 // IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF 00030 // OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 00031 // THE SOFTWARE. 00032 // 00033 // We acknowledge the C-to-C Translator from MIT Laboratory for 00034 // Computer Science for inspiring parts of the C-Breeze design. 00035 // 00036 // ---------------------------------------------------------------------- 00037 00038 #include "c_breeze.h" 00039 #include "scope_walker.h" 00040 00041 // ------------------------------------------------------------ 00042 // Constructor 00043 // ------------------------------------------------------------ 00044 00045 scope_walker::scope_walker(unitNode * u) 00046 : Walker(Both, Subtree), 00047 _unit(u), 00048 _ids(new Identifiers_table()), 00049 _tags(new Tags_table()), 00050 _externs(new Externals_table()), 00051 _symbol_level(0), 00052 _in_su(0), 00053 _in_enum(false), 00054 _in_formals(0) 00055 {} 00056 00057 scope_walker::~scope_walker() 00058 { 00059 //delete _ids; 00060 //delete _tags; 00061 //delete _externs; 00062 } 00063 00064 // ------------------------------------------------------------ 00065 // Keep track of context 00066 // ------------------------------------------------------------ 00067 00068 void scope_walker::at_suespec(suespecNode * the_suespec, Order ord) 00069 { 00070 NodeType owner = the_suespec->owner(); 00071 00072 if (ord == Preorder) 00073 if (owner == Enum) 00074 _in_enum++; 00075 else 00076 _in_su++; 00077 else 00078 if (owner == Enum) 00079 _in_enum--; 00080 else 00081 _in_su--; 00082 } 00083 00084 void scope_walker::at_func(funcNode * the_func, Order ord) 00085 { 00086 if (ord == Preorder) 00087 _in_formals++; 00088 else 00089 _in_formals--; 00090 } 00091 00092 // ------------------------------------------------------------ 00093 // Handle scope changes 00094 // ------------------------------------------------------------ 00095 00096 void scope_walker::at_block(blockNode * the_block, Order ord) 00097 { 00098 if (ord == Preorder) 00099 enter_scope(); 00100 00101 if (ord == Postorder) 00102 exit_scope(); 00103 } 00104 00105 // ------------------------------------------------------------ 00106 // Symbol table scope 00107 // ------------------------------------------------------------ 00108 00109 void scope_walker::enter_scope() 00110 { 00111 ids()->enter_scope(); 00112 tags()->enter_scope(); 00113 externs()->enter_scope(); 00114 00115 ++_symbol_level; 00116 } 00117 00118 void scope_walker::exit_scope() 00119 { 00120 if (_symbol_level == 0) 00121 CBZ::SyntaxError(string("missing '{' detected")); 00122 else { 00123 ids()->exit_scope(); 00124 tags()->exit_scope(); 00125 externs()->exit_scope(); 00126 00127 --_symbol_level; 00128 } 00129 } 00130