Add an "experimental" setting to disable injecting local variables into expressions.

This feature was added to solve a lookup problem in expressions when local variables
shadow ivars.  That solution requires fully realizing all local variables to evaluate
any expression, and can cause significant performance problems when evaluating 
expressions in frames that have many complex locals.

Until we get a better solution, this setting mitigates the problem when you don't
have local variables that shadow ivars.

<rdar://problem/27226122>

llvm-svn: 274783

1 files changed, 7 insertions, 3 deletions

diff --git a/lldb/source/Expression/ExpressionSourceCode.cpp b/lldb/source/Expression/ExpressionSourceCode.cpp
index d82ed608407..2d41d1a8b44 100644
--- a/lldb/source/Expression/ExpressionSourceCode.cpp
+++ b/lldb/source/Expression/ExpressionSourceCode.cpp
@@ -200,7 +200,8 @@ bool ExpressionSourceCode::GetText (std::string &text, lldb::LanguageType wrappi
     const char *target_specific_defines = "typedef signed char BOOL;\n";
     std::string module_macros;
     
-    if (Target *target = exe_ctx.GetTargetPtr())
+    Target *target = exe_ctx.GetTargetPtr();
+    if (target)
     {
         if (target->GetArchitecture().GetMachine() == llvm::Triple::aarch64)
         {
@@ -278,8 +279,11 @@ bool ExpressionSourceCode::GetText (std::string &text, lldb::LanguageType wrappi
         ConstString object_name;
         if (Language::LanguageIsCPlusPlus(frame->GetLanguage()))
         {
-            lldb::VariableListSP var_list_sp = frame->GetInScopeVariableList(false, true);
-            AddLocalVariableDecls(var_list_sp, lldb_local_var_decls);
+            if (target->GetInjectLocalVariables(&exe_ctx))
+            {
+                lldb::VariableListSP var_list_sp = frame->GetInScopeVariableList(false, true);
+                AddLocalVariableDecls(var_list_sp, lldb_local_var_decls);
+            }
         }
     }