hphp/compiler/statement/catch_statement.cpp

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-2013 Facebook, Inc. (http://www.facebook.com)     |
   6    +----------------------------------------------------------------------+
   7    | This source file is subject to version 3.01 of the PHP license,      |
   8    | that is bundled with this package in the file LICENSE, and is        |
   9    | available through the world-wide-web at the following url:           |
  10    | http://www.php.net/license/3_01.txt                                  |
  11    | If you did not receive a copy of the PHP license and are unable to   |
  12    | obtain it through the world-wide-web, please send a note to          |
  13    | license@php.net so we can mail you a copy immediately.               |
  14    +----------------------------------------------------------------------+
  15 */
  16
  17 #include "hphp/compiler/statement/catch_statement.h"
  18 #include "hphp/compiler/analysis/analysis_result.h"
  19 #include "hphp/compiler/analysis/block_scope.h"
  20 #include "hphp/compiler/analysis/function_scope.h"
  21 #include "hphp/compiler/analysis/variable_table.h"
  22 #include "hphp/compiler/expression/modifier_expression.h"
  23 #include "hphp/compiler/expression/scalar_expression.h"
  24 #include "hphp/compiler/analysis/code_error.h"
  25 #include "hphp/util/util.h"
  26 #include "hphp/compiler/analysis/class_scope.h"
  27 #include "hphp/compiler/option.h"
  28
  29 using namespace HPHP;
  30
  31 ///////////////////////////////////////////////////////////////////////////////
  32 // constructors/destructors
  33
  34 CatchStatement::CatchStatement
  35 (STATEMENT_CONSTRUCTOR_PARAMETERS,
  36  const std::string &className, const std::string &variable,
  37  StatementPtr stmt)
  38   : Statement(STATEMENT_CONSTRUCTOR_PARAMETER_VALUES(CatchStatement)),
  39     StaticClassName(ExpressionPtr(
  40                       new ScalarExpression(scope, loc,
  41                                            T_STRING, className, false))),
  42     m_variable(new SimpleVariable(scope, loc, variable)),
  43     m_stmt(stmt), m_valid(true) {
  44   m_variable->setContext(Expression::LValue);
  45 }
  46
  47 CatchStatement::CatchStatement
  48 (STATEMENT_CONSTRUCTOR_PARAMETERS,
  49  const std::string &className, const std::string &variable,
  50  StatementPtr stmt, StatementPtr finallyStmt)
  51   : Statement(STATEMENT_CONSTRUCTOR_PARAMETER_VALUES(CatchStatement)),
  52     StaticClassName(ExpressionPtr(
  53                       new ScalarExpression(scope, loc,
  54                                            T_STRING, className, false))),
  55     m_variable(new SimpleVariable(scope, loc, variable)),
  56     m_stmt(stmt), m_finallyStmt(finallyStmt), m_valid(true) {
  57   m_variable->setContext(Expression::LValue);
  58 }
  59
  60 StatementPtr CatchStatement::clone() {
  61   CatchStatementPtr stmt(new CatchStatement(*this));
  62   stmt->m_stmt = Clone(m_stmt);
  63   stmt->m_variable = Clone(m_variable);
  64   stmt->m_finallyStmt = Clone(m_finallyStmt);
  65   return stmt;
  66 }
  67
  68 ///////////////////////////////////////////////////////////////////////////////
  69 // parser functions
  70
  71 ///////////////////////////////////////////////////////////////////////////////
  72 // static analysis functions
  73
  74 void CatchStatement::analyzeProgram(AnalysisResultPtr ar) {
  75   addUserClass(ar, m_className);
  76   m_variable->analyzeProgram(ar);
  77   (void)resolveClass();
  78   if (m_stmt) m_stmt->analyzeProgram(ar);
  79   if (m_variable->isThis()) {
  80     // catch (Exception $this) { ... }
  81     // See note in alias_manager.cpp about why this forces a variable table
  82     VariableTablePtr variables(getScope()->getVariables());
  83     variables->forceVariants(ar, VariableTable::AnyVars);
  84     variables->setAttribute(VariableTable::ContainsLDynamicVariable);
  85   }
  86 }
  87
  88 ConstructPtr CatchStatement::getNthKid(int n) const {
  89   switch (n) {
  90     case 0:
  91       return m_variable;
  92     case 1:
  93       return m_stmt;
  94     case 2:
  95       return m_finallyStmt;
  96     default:
  97       assert(false);
  98       break;
  99   }
 100   return ConstructPtr();
 101 }
 102
 103 int CatchStatement::getKidCount() const {
 104   return 2 + (m_finallyStmt ? 1 : 0);
 105 }
 106
 107 void CatchStatement::setNthKid(int n, ConstructPtr cp) {
 108   switch (n) {
 109     case 0:
 110       m_variable = dynamic_pointer_cast<SimpleVariable>(cp);
 111       break;
 112     case 1:
 113       m_stmt = dynamic_pointer_cast<Statement>(cp);
 114       break;
 115     case 2:
 116       m_finallyStmt = dynamic_pointer_cast<Statement>(cp);
 117     default:
 118       assert(false);
 119       break;
 120   }
 121 }
 122
 123 void CatchStatement::inferTypes(AnalysisResultPtr ar) {
 124   ClassScopePtr cls = resolveClassWithChecks();
 125   TypePtr type;
 126   m_valid = cls || isRedeclared();
 127
 128   // This can never be a specific exception type, because a future exception
 129   // class may be re-declaring, then generated code like this won't work with
 130   // DynamicObjectData: p_exception v_e = e;
 131   type = Type::Object;
 132
 133   m_variable->inferAndCheck(ar, type, true);
 134   if (m_stmt) m_stmt->inferTypes(ar);
 135 }
 136
 137 ///////////////////////////////////////////////////////////////////////////////
 138
 139 void CatchStatement::outputCodeModel(CodeGenerator &cg) {
 140   cg.printObjectHeader("CatchStatement", 4);
 141   cg.printPropertyHeader("class");
 142   cg.printTypeExpression(m_origClassName);
 143   cg.printPropertyHeader("variableName");
 144   cg.printValue(m_variable->getName());
 145   cg.printPropertyHeader("block");
 146   cg.printAsEnclosedBlock(m_stmt);
 147   cg.printPropertyHeader("sourceLocation");
 148   cg.printLocation(this->getLocation());
 149   cg.printObjectFooter();
 150 }
 151
 152 ///////////////////////////////////////////////////////////////////////////////
 153 // code generation functions
 154
 155 void CatchStatement::outputPHP(CodeGenerator &cg, AnalysisResultPtr ar) {
 156   cg_printf(" catch (%s $%s) ", m_origClassName.c_str(),
 157             m_variable->getName().c_str());
 158   cg_indentBegin("{\n");
 159   if (m_stmt) m_stmt->outputPHP(cg, ar);
 160   cg_indentEnd("}");
 161 }