[lldb] Introduce StackFrameRecognizer [take 2]

This patch introduces a concept of "frame recognizer" and "recognized frame". This should be an extensible mechanism that retrieves information about special frames based on ABI, arguments or other special properties of that frame, even without source code. A few examples where that could be useful could be 1) objc_exception_throw, where we'd like to get the current exception, 2) terminate_with_reason and extracting the current terminate string, 3) recognizing Objective-C frames and automatically extracting the receiver+selector, or perhaps all arguments (based on selector).

Differential Revision: https://reviews.llvm.org/D44603

llvm-svn: 345686

1 files changed, 7 insertions, 0 deletions

diff --git a/lldb/source/Interpreter/OptionGroupVariable.cpp b/lldb/source/Interpreter/OptionGroupVariable.cpp
index 1bcddb4b49f7..f35aeb6aa555 100644
--- a/lldb/source/Interpreter/OptionGroupVariable.cpp
+++ b/lldb/source/Interpreter/OptionGroupVariable.cpp
@@ -28,6 +28,9 @@ static constexpr OptionDefinition g_variable_options[] = {
     {LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "no-args", 'a',
      OptionParser::eNoArgument, nullptr, {}, 0, eArgTypeNone,
      "Omit function arguments."},
+    {LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "no-recognized-args", 't',
+     OptionParser::eNoArgument, nullptr, {}, 0, eArgTypeNone,
+     "Omit recognized function arguments."},
     {LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "no-locals", 'l',
      OptionParser::eNoArgument, nullptr, {}, 0, eArgTypeNone,
      "Omit local variables."},
@@ -101,6 +104,9 @@ OptionGroupVariable::SetOptionValue(uint32_t option_idx,
   case 's':
     show_scope = true;
     break;
+  case 't':
+    show_recognized_args = false;
+    break;
   case 'y':
     error = summary.SetCurrentValue(option_arg);
     break;
@@ -119,6 +125,7 @@ OptionGroupVariable::SetOptionValue(uint32_t option_idx,
 void OptionGroupVariable::OptionParsingStarting(
     ExecutionContext *execution_context) {
   show_args = true;     // Frame option only
+  show_recognized_args = true; // Frame option only
   show_locals = true;   // Frame option only
   show_globals = false; // Frame option only
   show_decl = false;