[Lldb-commits] [lldb] r111053 - in /lldb/trunk: include/lldb/Expression/ClangExpressionVariable.h source/Expression/ClangExpressionVariable.cpp

[Sean Callanan]

Author: spyffe
Date: Fri Aug 13 17:52:29 2010
New Revision: 111053

URL: http://llvm.org/viewvc/llvm-project?rev=111053&view=rev
Log:
Documented ClangExpressionVariable(List), and
cleaned up its API slightly.

Modified:
    lldb/trunk/include/lldb/Expression/ClangExpressionVariable.h
    lldb/trunk/source/Expression/ClangExpressionVariable.cpp

Modified: lldb/trunk/include/lldb/Expression/ClangExpressionVariable.h
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/include/lldb/Expression/ClangExpressionVariable.h?rev=111053&r1=111052&r2=111053&view=diff
==============================================================================
--- lldb/trunk/include/lldb/Expression/ClangExpressionVariable.h (original)
+++ lldb/trunk/include/lldb/Expression/ClangExpressionVariable.h Fri Aug 13 17:52:29 2010
@@ -24,33 +24,83 @@
 
 namespace lldb_private {
 
+//----------------------------------------------------------------------
+/// @class ClangExpressionVariableList ClangExpressionVariable.h "lldb/Expression/ClangExpressionVariable.h"
+/// @brief Manages local variables that the expression interpreter uses.
+///
+/// The DWARF interpreter, when interpreting expressions, occasionally
+/// needs to interact with chunks of memory corresponding to local variable 
+/// values.  These locals are distinct from the externally-defined values
+/// handled by ClangExpressionDeclMap, and do not persist between expressions
+/// so they are not handled by ClangPersistentVariables.  They are kept in a 
+/// list, which is encapsulated in ClangEpxressionVariableList.
+//----------------------------------------------------------------------
 class ClangExpressionVariableList
 {
 public:
+    //----------------------------------------------------------------------
+    /// Constructor
+    //----------------------------------------------------------------------
     ClangExpressionVariableList();
+    
+    //----------------------------------------------------------------------
+    /// Destructor
+    //----------------------------------------------------------------------
     ~ClangExpressionVariableList();
 
+    //----------------------------------------------------------------------
+    /// Get or create the chunk of data corresponding to a given VarDecl.
+    ///
+    /// @param[in] var_decl
+    ///     The Decl for which a chunk of memory is to be allocated.
+    ///
+    /// @param[out] idx
+    ///     The index of the Decl in the list of variables.
+    ///
+    /// @param[in] can_create
+    ///     True if the memory should be created if necessary.
+    ///
+    /// @return
+    ///     A Value for the allocated memory.  NULL if the Decl couldn't be 
+    ///     found and can_create was false, or if some error occurred during
+    ///     allocation.
+    //----------------------------------------------------------------------
     Value *
-    GetVariableForVarDecl (clang::ASTContext &ast_context, 
-                           const clang::VarDecl *var_decl, 
+    GetVariableForVarDecl (const clang::VarDecl *var_decl, 
                            uint32_t& idx, 
                            bool can_create);
 
+    //----------------------------------------------------------------------
+    /// Get the chunk of data corresponding to a given index into the list.
+    ///
+    /// @param[in] idx
+    ///     The index of the Decl in the list of variables.
+    ///
+    /// @return
+    ///     The value at the given index, or NULL if there is none.
+    //----------------------------------------------------------------------
     Value *
     GetVariableAtIndex (uint32_t idx);
-    
-    uint32_t
-    AppendValue (Value *value); // takes ownership
-
 private:
+    //----------------------------------------------------------------------
+    /// @class ClangExpressionVariable ClangExpressionVariable.h "lldb/Expression/ClangExpressionVariable.h"
+    /// @brief Manages one local variable for the expression interpreter.
+    ///
+    /// The expression interpreter uses specially-created Values to hold its
+    /// temporary locals.  These Values contain data buffers holding enough
+    /// space to contain a variable of the appropriate type.  The VarDecls
+    /// are only used while creating the list and generating the DWARF code for
+    /// an expression; when interpreting the DWARF, the variables are identified
+    /// only by their index into the list of variables.
+    //----------------------------------------------------------------------
     struct ClangExpressionVariable
     {
-        const clang::VarDecl    *m_var_decl;
-        Value                   *m_value;
+        const clang::VarDecl    *m_var_decl;    ///< The VarDecl corresponding to the parsed local.
+        Value                   *m_value;       ///< The LLDB Value containing the data for the local.
     };
     
     typedef std::vector<ClangExpressionVariable> Variables;
-    Variables m_variables;
+    Variables m_variables;                                  ///< The list of variables used by the expression.
 };
 
 } // namespace lldb_private

Modified: lldb/trunk/source/Expression/ClangExpressionVariable.cpp
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Expression/ClangExpressionVariable.cpp?rev=111053&r1=111052&r2=111053&view=diff
==============================================================================
--- lldb/trunk/source/Expression/ClangExpressionVariable.cpp (original)
+++ lldb/trunk/source/Expression/ClangExpressionVariable.cpp Fri Aug 13 17:52:29 2010
@@ -33,14 +33,14 @@
 }
 
 Value *
-ValueForDecl(ASTContext &ast_context, const VarDecl *var_decl)
+ValueForDecl(const VarDecl *var_decl)
 {
     Value *ret = new Value;
         
     ret->SetContext(Value::eContextTypeOpaqueClangQualType, 
                     var_decl->getType().getAsOpaquePtr());
     
-    uint64_t bit_width = ast_context.getTypeSize(var_decl->getType());
+    uint64_t bit_width = var_decl->getASTContext().getTypeSize(var_decl->getType());
     
     uint32_t byte_size = (bit_width + 7 ) / 8;
     
@@ -50,7 +50,7 @@
 }
 
 Value *
-ClangExpressionVariableList::GetVariableForVarDecl (ASTContext &ast_context, const VarDecl *var_decl, uint32_t& idx, bool can_create)
+ClangExpressionVariableList::GetVariableForVarDecl (const VarDecl *var_decl, uint32_t& idx, bool can_create)
 {
     uint32_t num_variables = m_variables.size();
     uint32_t var_index;
@@ -71,7 +71,7 @@
     
     ClangExpressionVariable val;
     val.m_var_decl = var_decl;
-    val.m_value = ValueForDecl(ast_context, var_decl);
+    val.m_value = ValueForDecl(var_decl);
     m_variables.push_back(val);
     
     return m_variables.back().m_value;
@@ -85,16 +85,3 @@
     
     return NULL;
 }
-
-uint32_t
-ClangExpressionVariableList::AppendValue (Value *value)
-{
-    uint32_t idx = m_variables.size();
-    
-    ClangExpressionVariable val;
-    val.m_var_decl = NULL;
-    val.m_value = value;
-    
-    m_variables.push_back(val);
-    return idx;
-}