From e2d0db0617ba4250d30e9952395e91ddf18b2e0f Mon Sep 17 00:00:00 2001
From: Grant Karapetyan <gkarapetyan@adalisk.com>
Date: Wed, 28 Sep 2022 17:02:11 +0400
Subject: [PATCH 1/2] Print active timer branch on crash

---
 source/MRMesh/MRLog.cpp      |  3 +++
 source/MRMesh/MRTimer.cpp    | 47 ++++++++++++++++++++++++++++++------
 source/MRMesh/MRTimer.h      | 10 +++++---
 source/MRViewer/MRViewer.cpp |  1 +
 4 files changed, 50 insertions(+), 11 deletions(-)

diff --git a/source/MRMesh/MRLog.cpp b/source/MRMesh/MRLog.cpp
index 0bb33a8a0889..f03b16882108 100644
--- a/source/MRMesh/MRLog.cpp
+++ b/source/MRMesh/MRLog.cpp
@@ -3,6 +3,7 @@
 #include "MRSystem.h"
 #include "MRStringConvert.h"
 #include "MRPch/MRSpdlog.h"
+#include "MRTimer.h"
 
 #ifndef __EMSCRIPTEN__
 #include <boost/stacktrace.hpp>
@@ -35,6 +36,8 @@ void crashSignalHandler( int signal )
     auto stacktrace = boost::stacktrace::stacktrace();
     for ( const auto& frame : stacktrace )
         spdlog::critical( "{} {} {}", frame.name(), frame.source_file(), frame.source_line() );
+
+    MR::printCurrentTimerBranch();
     std::exit( signal );
 }
 #endif
diff --git a/source/MRMesh/MRTimer.cpp b/source/MRMesh/MRTimer.cpp
index 3b306cc88516..275d7ecd7ff9 100644
--- a/source/MRMesh/MRTimer.cpp
+++ b/source/MRMesh/MRTimer.cpp
@@ -11,6 +11,7 @@ namespace MR
 
 struct TimeRecord
 {
+    TimeRecord* parent = nullptr;
     int count = 0;
     nanoseconds time = {};
     std::map<std::string, TimeRecord> children;
@@ -82,32 +83,64 @@ void printTimingTreeAtEnd( bool on )
     rootTimeRecord.printTreeInDtor = on;
 }
 
+void printCurrentTimerBranch()
+{
+    Timer t( "Print Timer branch leaf" );
+    const TimeRecord* active = currentRecord;
+    auto& logger = rootTimeRecord.loggerHandle;
+    if ( !logger )
+        return;
+    while ( active )
+    {
+        if ( !active->parent )
+        {
+            logger->info( "Root" );
+            break;
+        }
+        for ( const auto& child : active->parent->children )
+        {
+            if ( &child.second != active )
+                continue;
+            logger->info( child.first );
+            break;
+        }
+        active = active->parent;
+    }
+}
+
 void printTimingTreeAndStop()
 {
     rootTimeRecord.printTree();
     printTimingTreeAtEnd( false );
 }
 
-void Timer::restart( std::string name )
+void Timer::restart( const std::string& name )
 {
     finish();
+    start( name );
+}
+
+void Timer::start( const std::string& name )
+{
     if ( std::this_thread::get_id() != mainThreadId )
         return;
-    name_ = std::move( name );
     start_ = high_resolution_clock::now();
-    parent_ = currentRecord;
-    currentRecord = &currentRecord->children[name_];
+    auto parent = currentRecord;
+    currentRecord = &parent->children[name];
+    currentRecord->parent = parent;
 }
 
 void Timer::finish()
 {
-    if ( !parent_ )
+    auto& currentParent = currentRecord->parent;
+    if ( !currentParent )
         return;
 
     currentRecord->time += high_resolution_clock::now() - start_;
     ++currentRecord->count;
-    currentRecord = parent_;
-    parent_ = nullptr;
+
+    currentRecord = currentParent;
+    currentParent = nullptr;
 }
 
 } //namespace MR
diff --git a/source/MRMesh/MRTimer.h b/source/MRMesh/MRTimer.h
index 2c91653b269c..a53633a784e6 100644
--- a/source/MRMesh/MRTimer.h
+++ b/source/MRMesh/MRTimer.h
@@ -15,10 +15,11 @@ struct TimeRecord;
 class Timer
 {
 public:
-    Timer( std::string name ) { restart( std::move( name ) ); }
+    Timer( const std::string& name ) { start( name ); }
     ~Timer() { finish(); }
 
-    MRMESH_API void restart( std::string name );
+    MRMESH_API void restart( const std::string& name );
+    MRMESH_API void start( const std::string& name );
     MRMESH_API void finish();
 
     Timer( const Timer & ) = delete;
@@ -29,14 +30,15 @@ class Timer
     std::chrono::duration<double> secondsPassed() const { return std::chrono::high_resolution_clock::now() - start_; }
 
 private:
-    TimeRecord * parent_ = nullptr;
     std::chrono::time_point<std::chrono::high_resolution_clock> start_;
-    std::string name_;
 };
 
 /// enables or disables printing of timing tree when application terminates
 MRMESH_API void printTimingTreeAtEnd( bool on );
 
+/// prints current timer branch
+MRMESH_API void printCurrentTimerBranch();
+
 /// prints the current timing tree, then calls printTimingTreeAtEnd( false );
 MRMESH_API void printTimingTreeAndStop();
 
diff --git a/source/MRViewer/MRViewer.cpp b/source/MRViewer/MRViewer.cpp
index 555a22f9edf9..16c5bdb0bfaa 100644
--- a/source/MRViewer/MRViewer.cpp
+++ b/source/MRViewer/MRViewer.cpp
@@ -227,6 +227,7 @@ int launchDefaultViewer( const Viewer::LaunchParams& params, const ViewerSetup&
         auto stacktrace = boost::stacktrace::stacktrace();
         for ( const auto& frame : stacktrace )
             spdlog::critical( "{} {} {}", frame.name(), frame.source_file(), frame.source_line() );
+        printCurrentTimerBranch();
         res = 1;
     }
 

From 32c2a51d073f3d1693d9edda3d9a7b27655b15fb Mon Sep 17 00:00:00 2001
From: Grant Karapetyan <gkarapetyan@adalisk.com>
Date: Wed, 28 Sep 2022 18:09:43 +0400
Subject: [PATCH 2/2] Fix UB

---
 source/MRMesh/MRTimer.cpp | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/source/MRMesh/MRTimer.cpp b/source/MRMesh/MRTimer.cpp
index 275d7ecd7ff9..e52370ac2959 100644
--- a/source/MRMesh/MRTimer.cpp
+++ b/source/MRMesh/MRTimer.cpp
@@ -132,7 +132,7 @@ void Timer::start( const std::string& name )
 
 void Timer::finish()
 {
-    auto& currentParent = currentRecord->parent;
+    auto currentParent = currentRecord->parent;
     if ( !currentParent )
         return;
 
@@ -140,7 +140,6 @@ void Timer::finish()
     ++currentRecord->count;
 
     currentRecord = currentParent;
-    currentParent = nullptr;
 }
 
 } //namespace MR