[Lldb-commits] [lldb] [lldb] Create ThreadPlanStepOut ctor that never skips frames (PR #136163)

[Felipe de Azevedo Piovezan via lldb-commits]

https://github.com/felipepiovezan updated https://github.com/llvm/llvm-project/pull/136163

>From d1f15f7a23b75d7b68989ac84b1c4b5991fb120d Mon Sep 17 00:00:00 2001
From: Felipe de Azevedo Piovezan <fpiovezan at apple.com>
Date: Thu, 17 Apr 2025 09:36:22 -0700
Subject: [PATCH 1/2] [lldb] Create ThreadPlanStepOut ctor that never skips
 frames

The function QueueThreadPlanForStepOutNoShouldStop has the semantics of
"go this parent frame"; ThreadPlanStepOut needs to respect that, not
skipping over any frames it finds uninteresting. This commit creates a
constructor that respects such instruction.
---
 lldb/include/lldb/Target/ThreadPlanStepOut.h |  9 ++++++++
 lldb/source/Target/Thread.cpp                |  5 ++---
 lldb/source/Target/ThreadPlanStepOut.cpp     | 22 ++++++++++++++++++++
 3 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/lldb/include/lldb/Target/ThreadPlanStepOut.h b/lldb/include/lldb/Target/ThreadPlanStepOut.h
index e414a6e0a2d49..9a62f6102d368 100644
--- a/lldb/include/lldb/Target/ThreadPlanStepOut.h
+++ b/lldb/include/lldb/Target/ThreadPlanStepOut.h
@@ -17,6 +17,9 @@ namespace lldb_private {
 
 class ThreadPlanStepOut : public ThreadPlan, public ThreadPlanShouldStopHere {
 public:
+  /// Creates a thread plan to step out from frame_idx, skipping parent frames
+  /// that artificial and hidden frames. Also skips frames without debug info
+  /// based on step_out_avoids_code_without_debug_info.
   ThreadPlanStepOut(Thread &thread, SymbolContext *addr_context,
                     bool first_insn, bool stop_others, Vote report_stop_vote,
                     Vote report_run_vote, uint32_t frame_idx,
@@ -24,6 +27,12 @@ class ThreadPlanStepOut : public ThreadPlan, public ThreadPlanShouldStopHere {
                     bool continue_to_next_branch = false,
                     bool gather_return_value = true);
 
+  /// Creates a thread plan to step out from frame_idx to frame_idx + 1.
+  ThreadPlanStepOut(Thread &thread, bool stop_others, Vote report_stop_vote,
+                    Vote report_run_vote, uint32_t frame_idx,
+                    bool continue_to_next_branch = false,
+                    bool gather_return_value = true);
+
   ~ThreadPlanStepOut() override;
 
   void GetDescription(Stream *s, lldb::DescriptionLevel level) override;
diff --git a/lldb/source/Target/Thread.cpp b/lldb/source/Target/Thread.cpp
index accc4708c24e1..b0e0f1e67c060 100644
--- a/lldb/source/Target/Thread.cpp
+++ b/lldb/source/Target/Thread.cpp
@@ -1360,9 +1360,8 @@ ThreadPlanSP Thread::QueueThreadPlanForStepOutNoShouldStop(
   const bool calculate_return_value =
       false; // No need to calculate the return value here.
   ThreadPlanSP thread_plan_sp(new ThreadPlanStepOut(
-      *this, addr_context, first_insn, stop_other_threads, report_stop_vote,
-      report_run_vote, frame_idx, eLazyBoolNo, continue_to_next_branch,
-      calculate_return_value));
+      *this, stop_other_threads, report_stop_vote, report_run_vote, frame_idx,
+      continue_to_next_branch, calculate_return_value));
 
   ThreadPlanStepOut *new_plan =
       static_cast<ThreadPlanStepOut *>(thread_plan_sp.get());
diff --git a/lldb/source/Target/ThreadPlanStepOut.cpp b/lldb/source/Target/ThreadPlanStepOut.cpp
index f2606403016a6..0628451a5abf9 100644
--- a/lldb/source/Target/ThreadPlanStepOut.cpp
+++ b/lldb/source/Target/ThreadPlanStepOut.cpp
@@ -83,6 +83,28 @@ ThreadPlanStepOut::ThreadPlanStepOut(
                      continue_to_next_branch);
 }
 
+ThreadPlanStepOut::ThreadPlanStepOut(Thread &thread, bool stop_others,
+                                     Vote report_stop_vote,
+                                     Vote report_run_vote, uint32_t frame_idx,
+                                     bool continue_to_next_branch,
+                                     bool gather_return_value)
+    : ThreadPlan(ThreadPlan::eKindStepOut, "Step out", thread, report_stop_vote,
+                 report_run_vote),
+      ThreadPlanShouldStopHere(this), m_return_bp_id(LLDB_INVALID_BREAK_ID),
+      m_return_addr(LLDB_INVALID_ADDRESS), m_stop_others(stop_others),
+      m_immediate_step_from_function(nullptr),
+      m_calculate_return_value(gather_return_value) {
+  SetFlagsToDefault();
+  m_step_from_insn = thread.GetRegisterContext()->GetPC(0);
+
+  StackFrameSP return_frame_sp = thread.GetStackFrameAtIndex(frame_idx + 1);
+  StackFrameSP immediate_return_from_sp =
+      thread.GetStackFrameAtIndex(frame_idx);
+
+  SetupReturnAddress(return_frame_sp, immediate_return_from_sp, frame_idx,
+                     continue_to_next_branch);
+}
+
 void ThreadPlanStepOut::SetupReturnAddress(
     StackFrameSP return_frame_sp, StackFrameSP immediate_return_from_sp,
     uint32_t frame_idx, bool continue_to_next_branch) {

>From b1665da9637d16d91ba7a08ff9ad884c0b87c490 Mon Sep 17 00:00:00 2001
From: Felipe de Azevedo Piovezan <fpiovezan at apple.com>
Date: Thu, 17 Apr 2025 13:48:08 -0700
Subject: [PATCH 2/2] fixup! Update comment

---
 lldb/include/lldb/Target/ThreadPlanStepOut.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lldb/include/lldb/Target/ThreadPlanStepOut.h b/lldb/include/lldb/Target/ThreadPlanStepOut.h
index 9a62f6102d368..ad4434be14120 100644
--- a/lldb/include/lldb/Target/ThreadPlanStepOut.h
+++ b/lldb/include/lldb/Target/ThreadPlanStepOut.h
@@ -18,8 +18,8 @@ namespace lldb_private {
 class ThreadPlanStepOut : public ThreadPlan, public ThreadPlanShouldStopHere {
 public:
   /// Creates a thread plan to step out from frame_idx, skipping parent frames
-  /// that artificial and hidden frames. Also skips frames without debug info
-  /// based on step_out_avoids_code_without_debug_info.
+  /// if they are artificial or hidden frames. Also skips frames without debug
+  /// info based on step_out_avoids_code_without_debug_info.
   ThreadPlanStepOut(Thread &thread, SymbolContext *addr_context,
                     bool first_insn, bool stop_others, Vote report_stop_vote,
                     Vote report_run_vote, uint32_t frame_idx,