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Copyright © 2017 Samsung. All Rights Reserved.

Debugger and Profiler for Tizen .NET Igor Kulaychuk i.kulaychuk@samsung.com

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Igor Kulaychuk •  Leading Software Engineer at Samsung R&D Institute Russia •  Part of Tizen .NET team •  Responsible for development of Debugger for Tizen .NET Experience: •  Development of testing and debugging tools for Android/Tizen •  C/C++/Linux/ptrace

About me

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Visual Studio Tools for Tizen .NET Debugger / Profiler

–  overview –  demo

Outline

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Application Development

Tizen  .NET  •  Visual  Studio  integra5on  •  Xamarin.Forms  •  Tizen  Emulator  •  .NET  Core  •  Tizen  pla;orm-­‐specific  API  

C and EFL HTML5 OR   ?  

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Visual Studio integration https://github.com/Microsoft/MIEngine Modified .NET Core https://github.com/dotnet/coreclr Debugger is based on LLDB

Debugger

Visual Studio

MIEngine sdb LLDB

App

.NET Core

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•  Application: – FizzBuzz (bug: prints “Buzz” on 15)

•  Debugging scenario:

– Put breakpoint at the start of new list item generation code – Add condition currentNumber  ==  15  – Step through code and find where the bug occurs

Debugger Demo

1  2  Fizz  4  Buzz  …  14  FizzBuzz  16  

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DEMO Debugger demo

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Profiler

Visual Studio integration using custom profiler UI Profiler is based on Linux Trace Toolkit Next Generation http://lttng.org

Visual Studio

Profiler UI sdb LTTng

App

.NET Core

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•  Application: – Run application under Profiler

•  Profiling scenario:

– Observer CPU/Memory consumption in real time – View Profiler session file – View hot lines

Profiler Demo

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DEMO Profiler demo

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Build, debug and profile your applications using .NET with Visual Studio •  Download at: https://developer.tizen.org/ •  Contact me: i.kulaychuk@samsung.com https://github.com/ayuckhulk

Conclusion

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Thank you!

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Implementation details

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App

•  GDB/MI – line based text interface to debugger •  MIEngine – open source Visual Studio MI Debug engine

(by Microsoft) – works with gdb, lldb, clrdbg

•  GDB JIT – provides the debugger info for code generated at runtime

Implementation details

Visual Studio MIEngine sdb lldb-mi .NET

Core GDB  JIT  

Modify

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•  Generate ELF in memory with DWARF debug info – Line numbers – Local variables with scopes – Method arguments – Types

.NET Core modifications - DWARF

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•  On method compilation – Generate ELF in memory – Trigger __jit_debug_register_code function – debugger consumes generated ELF from

__jit_debug_descriptor variable

.NET Core modifications - GDBJIT

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•  License •  Relatively easy to add a new language •  Supports different architectures •  Has GDB/MI implementation •  .NET Core has a plugin for inspecting runtime internals

LLDB – Why?

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•  ThreadPlan •  Method native code does not exist before it is called •  Step-over for exceptions handlers are really step-in

LLDB - Stepping

try  {          SomeMethod();  }  catch  (Exception  e)  {          ShowError(e);  }  

void  SomeMethod()  {          DoSomething();  }  

step-in internal breakpoint

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•  Formatters – Decimals, strings etc. – Display {MyClass}  instead of 0x0000FFFFF730966A etc.

•  Synthetics – Hide internal class variables (like _count  for arrays) – Show inherited fields like CLRDBG

LLDB – Data visualization

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Thank you!