Fixed the "expression" command object to use the StackFrame::GetValueForExpressionPath()

function and also hooked up better error reporting for when things fail.

Fixed issues with trying to display children of pointers when none are
supposed to be shown (no children for function pointers, and more like this).
This was causing child value objects to be made that were correctly firing
an assertion.

llvm-svn: 121841

1 files changed, 25 insertions, 76 deletions

diff --git a/lldb/source/Core/ValueObject.cpp b/lldb/source/Core/ValueObject.cpp
index 60b1009ad7a..2f82d49bd0b 100644
--- a/lldb/source/Core/ValueObject.cpp
+++ b/lldb/source/Core/ValueObject.cpp
@@ -1203,10 +1203,11 @@ ValueObject::CreateConstantValue (ExecutionContextScope *exe_scope, const ConstS
 }
 
 lldb::ValueObjectSP
-ValueObject::Dereference (ExecutionContextScope *exe_scope, Error *error_ptr)
+ValueObject::Dereference (ExecutionContextScope *exe_scope, Error &error)
 {
     lldb::ValueObjectSP valobj_sp;
-    if (IsPointerType())
+    const bool is_pointer_type = IsPointerType();
+    if (is_pointer_type)
     {
         bool omit_empty_base_classes = true;
 
@@ -1249,98 +1250,46 @@ ValueObject::Dereference (ExecutionContextScope *exe_scope, Error *error_ptr)
                                                    child_is_base_class));
         }
     }
+
+    if (valobj_sp)
+    {
+        error.Clear();
+    }
     else
     {
-        if (error_ptr)
-            error_ptr->SetErrorString("can't dereference a non-pointer value");
+        StreamString strm;
+        GetExpressionPath(strm);
+
+        if (is_pointer_type)
+            error.SetErrorStringWithFormat("dereference failed: (%s) %s", GetTypeName().AsCString("<invalid type>"), strm.GetString().c_str());
+        else
+            error.SetErrorStringWithFormat("not a pointer type: (%s) %s", GetTypeName().AsCString("<invalid type>"), strm.GetString().c_str());
     }
 
     return valobj_sp;
 }
 
-    
-
-//lldb::ValueObjectSP
-//ValueObject::Dereference (ExecutionContextScope *exe_scope, Error *error_ptr)
-//{
-//    lldb::ValueObjectSP valobj_sp;
-//    if (IsPointerType())
-//    {
-//        UpdateValueIfNeeded(exe_scope);
-//        if (m_error.Success())
-//        {
-//            lldb::AddressType address_type = eAddressTypeInvalid;
-//            const bool scalar_is_load_address = true;
-//            lldb::addr_t addr = GetPointerValue (address_type, scalar_is_load_address);
-//            if (addr != LLDB_INVALID_ADDRESS)
-//            {
-//                switch (address_type)
-//                {
-//                    case eAddressTypeInvalid:
-//                        if (error_ptr)
-//                            error_ptr->SetErrorString("value is not in memory");
-//                        break;
-//                    case eAddressTypeFile:
-//                    case eAddressTypeLoad:
-//                    case eAddressTypeHost:
-//                    {
-//                        clang::ASTContext *ast = GetClangAST();
-//                        clang_type_t clang_type = ClangASTType::GetPointeeType (GetClangType());
-//                        if (ast && clang_type)
-//                        {
-//                            std::string name (1, '*');
-//                            name.append (m_name.AsCString(""));
-//                            valobj_sp.reset (new ValueObjectConstResult (ast, 
-//                                                                         ClangASTContext::CreatePointerType (ast, clang_type),
-//                                                                         ConstString (name.c_str()),
-//                                                                         addr, 
-//                                                                         address_type,
-//                                                                         m_data.GetAddressByteSize()));
-//                        }
-//                        else
-//                        {
-//                            if (error_ptr)
-//                                error_ptr->SetErrorString("invalid clang type info");
-//                        }
-//                    }
-//                    break;
-//                }
-//            }
-//            else
-//            {
-//                if (error_ptr)
-//                    error_ptr->SetErrorString("failed to extract pointer value");
-//            }
-//        }
-//        else
-//        {
-//            if (error_ptr)
-//                *error_ptr = m_error;
-//        }
-//    }
-//    else
-//    {
-//        if (error_ptr)
-//            error_ptr->SetErrorString("can't dereference a non-pointer value");
-//    }
-//
-//    return valobj_sp;
-//}
-    
-lldb::ValueObjectSP
-ValueObject::AddressOf ()
+    lldb::ValueObjectSP
+ValueObject::AddressOf (Error &error)
 {
     lldb::ValueObjectSP valobj_sp;
-
     lldb::AddressType address_type = eAddressTypeInvalid;
     const bool scalar_is_load_address = false;
     lldb::addr_t addr = GetAddressOf (address_type, scalar_is_load_address);
+    error.Clear();
     if (addr != LLDB_INVALID_ADDRESS)
     {
         switch (address_type)
         {
+        default:
         case eAddressTypeInvalid:
+            {
+                StreamString expr_path_strm;
+                GetExpressionPath(expr_path_strm);
+                error.SetErrorStringWithFormat("'%s' is not in memory", expr_path_strm.GetString().c_str());
+            }
             break;
+
         case eAddressTypeFile:
         case eAddressTypeLoad:
         case eAddressTypeHost: