This was last updated in January 2019. It may be out of date. If you want me to update it or have any questions, please contact me by email at: clattner@nondot.org.

Chris Lattner

My overall objective is to improve large software systems through the development of novel techniques as well as the application of known engineering principles. I am a proven technical leader, who likes to grapple with hard engineering problems that most people assume are impossible to solve. I enjoy leading by example and getting my hands dirty in code. I have worked in many spaces, including things as diverse as low level machine code optimization, compiler optimization, programming language design, IDE features, built the Swift Playgrounds iPad app, and ran a team at Tesla applying a diverse range of tech in the autonomous car space (including machine learning, computer vision, sensors and non-vision perception, robotics planning and control, mapping, cloud infrastructure, embedded systems, and simulation), and have built and managed an array of AI-related teams in Google Brain.

I am the founder and chief architect of the open source LLVM Compiler Infrastructure project, and serve on the board of directors of the LLVM Foundation. LLVM has grown to include a broad range of compiler, debugger, and runtime library technologies. Assembled out of this technology are things like the Clang compiler, the LLDB debugger, the Clang Static Analyzer, and other low-level tools. LLVM is widely used for academic research projects, has been adopted for commercial use by several companies, and has a broad and growing developer base. For more information, please see the LLVM web page: http://llvm.org/.

I am also the founder of the Swift Programming Language, which is open source at Swift.org and GitHub. Swift has been steadily and rapidly growing ever since its launch, with over 100,000 apps in the Apple app stores, is installed on millions of developer workstations, and is widely loved by people who use it. Since its release as open source, Swift is rapidly growing in the server space and in other domains outside of the traditional Apple developer community.

I am a strong leader and have excellent communication skills (both verbal and written). I occasionally give talks explaining and evangelizing TensorFlow, Swift, LLVM, Clang, and other technologies I have worked on. I also co-founded and contribute to the Swift Community Podcast in my spare time.

Resume Contents:

• Awards
• Work History
• Education
• Invited Talks
• Writen Work and Publications
• Other Interests and Activities

Awards and Recognition

Notable awards:

• 2016: Recognized as one of Wired's "25 Geniuses who are creating the future of business".
• 2014: Received the Test of Time Award for the most influential paper of CGO 2004 (awarded at CGO 2014).
• 2013: Received the 2013 Distinguished Alumni Achievement Award by the University of Illinois Computer Science Department.
• 2012: LLVM was awarded the ACM Software Systems Award which recognizes a software system that has had a lasting influence, reflected in contributions to concepts, in commercial acceptance, or both (across the entire software industry). Previous recipients include Java, Apache, the World-Wide Web, SMALLTALK, UNIX, and many other notable software systems.
• 2010: Received the ACM SIGPLAN Programming Languages Software Award in recognition of my work on LLVM. SIGPLAN is the ACM Organization focusing on Programming Language Design and Implementation. Being the first year this was awarded is notable, because all programming language software systems were eligible.

Work History

Google

• Senior Director and Distinguished Engineer, TensorFlow Infrastructure and Technologies
  August 2017 - current

  The TensorFlow team is an incredibly dynamic and fast moving team, incorporating multiple cross-cutting concerns that I love to work on and with. This includes complex product issues, Open Source infrastructure, deep technical challenges, new hardware platforms, and a race with the rest of the industry. At the time of this writing (Jan 2019) I'm driving three main projects:

  • TensorFlow Accelerator Support and Compiler Infrastructure: I lead teams responsible for TensorFlow CPU, GPU and TPU ("Tensor Processing Units") support, including the XLA compiler team, and TensorFlow graph transformations.

  • Swift for TensorFlow: Swift for TensorFlow rethinks machine learning development by opening the programming language to extension and change - allowing us to solve old problems in new ways. This project includes a combination of compiler, runtime, and programming language design and implementation work. I imagined, advocated for, coded the initial prototype and many of the subsystems after that; recruited, hired and trained an exceptional engineering team; we drove it to an open source launch and are continuing to build out and iterate on infrastructure. We are now intentionally maintaining a low profile as we are building out infrastructure, but aim to start pushing for it in the first half of 2019. If you'd like to participate or follow along, please join our community.

  • MLIR: A New Compiler Infrastructure for Machine Learning: I am driving a (still in stealth mode) project to build key compiler and runtime infrastructure underlying TensorFlow and its support for a very wide range of high performance accelerators. This project is driven by the increased generality of new hardware and programming models, as well as the need to enable rapid bringup of new hardware - sometimes with wildly different capabilities and target markets. This is a large scale project pushing the boundaries of fundamental compiler technology - we are aware of and build on key concepts from existing systems, but are innovating in all areas of compiler architecture and design. We expect to announce and open-source this project when the time is right.

  Incidentally, I'm actively hiring a for a large number of engineer, manager, and tech lead positions (up to Director / Principle Engineer level) for the above projects - if you are experienced and interested, please get in touch with me.

Tesla

• VP Autopilot Software
  January 30 - June 20, 2017

  When I joined Tesla, it was in the midst of a hardware transition from "Hardware 1" Autopilot (based primarily on MobileEye for vision processing) to "Hardware 2", which uses an in-house designed TeslaVision stack. The team was facing many tough challenges given the nature of the transition. My primary contributions over these fast five months were:

  • We evolved Autopilot for HW2 from its first early release (which had few capabilities and was limited to 45mph on highways) to effectively parity with HW1, and surpassing it in some ways (e.g. silky smooth control).
  • This required building and shipping numerous features for HW2, including: support for local roads, Parallel Autopark, High Speed Autosteer, Summon, Lane Departure Warning, Automatic Lane Change, Low Speed AEB, Full Speed Autosteer, Pedal Misapplication Mitigation, Auto High Beams, Side Collision Avoidance, Full Speed AEB, Perpendicular Autopark, and 'silky smooth' performance.
  • This was done by shipping a total of 7 major feature releases, as well as numerous minor releases to support factory, service, and other narrow markets.
  • One of Tesla's huge advantages in the autonomous driving space is that it has tens of thousands of cars already on the road. We built infrastructure to take advantage of this, allowing the collection of image and video data from this fleet, as well as building big data infrastructure in the cloud to process and use it.
  • I defined and drove the feature roadmap, drove the technical architecture for future features, and managed the implementation for the next exciting features to come.
  • I advocated for and drove a major rewrite of the deep net architecture in the vision stack, leading to significantly better precision, recall, and inference performance.
  • I ended up growing the Autopilot Software team by over 50%. I personally interviewed most of the accepted candidates.
  • I improved internal infrastructure and processes that I cannot go into detail about.
  • I was closely involved with others in the broader Autopilot program, including future hardware support, legal, homologation, regulatory, marketing, etc.

  Overall I learned a lot, worked hard, met a lot of great people, and had a lot of fun. I'm still a firm believer in Tesla, its mission, and the exceptional Autopilot team: I wish them well.

Apple

• Apple: Developer Tools Department
  Senior Director and Architect, Developer Tools Department
  January 2013 - January 2017

  In January 2013, I took over management and leadership of the entire Developer Tools department at Apple (~200 people). In addition to languages (Swift and Objective-C), compilers and low-level tools, I took on responsibility for the Xcode IDE, Instruments performance analysis tool, Apple Java releases, and a variety of internal tools.

  In this time period, my team shipped a number of major Xcode releases, including Xcode 4.6, 5.x, 6.x, 7.x, and 8.x, each with major feature enhancements. Some of my more notable contributions include:

  • ARM64: Over a 3 year span, I drove definition, bringup and implementation work of the ARM64 (aka Aarch64) compiler toolchain - the first production quality compiler for this architecture in the world - which shipped in Xcode 5. This enabled the iPhone 5s, which shocked the world with its 64-bit support and superb performance. In addition to compiler work, I contributed to the design of a new Objective-C runtime object model for the architecture, and I personally contributed the "TBI" feature to ARM, which was incorporated in the Aarch64 architecture.
  • iPhone GPU Compiler: we implemented a completely new LLVM-based runtime GPU shader compiler. This started shipping in iOS7 to support the iPhone 5s - which featured a VLIW PowerVR Rogue GPU derivative, and has been extended to support later iPhone hardware as it comes out. Compared to the vendor compiler it replaced, this GPU compiler produces code that runs slightly faster, and takes much less compile time to generate it.
  • Xcode 5 was a major release, notable for me in that it was the first release with a completely LLVM-based low-level toolchain (Clang, LLDB, etc) - it dropped the last support for GCC and GDB. This transition was largely driven by the ARM64 architecture transition.
  • Swift: The most prominent feature of Xcode 6 was Swift, a new programming language that I had been personally driving since 2010. In addition to the language design and implementation, I drove much of the compiler architecture (e.g. the SIL high-level IR), the REPL and Playgrounds feature designs, drove and coordinated the rest of the team to implement full Xcode and documentation support for a language that was still rapidly evolving. We managed to keep extremely tight secrecy until a great launch at WWDC 2014.
  • I was the primary proponent for the Official Swift Blog and wrote many of the posts.
  • I drove Swift Open Source to happen, and was extensively involved defining exactly what that meant.
  • I was one of the few core people who drove Swift Playgrounds for iPad, including conception, design, implementation, and iteration.
  • I was a member of Apple's senior executive leadership team, and drove a number of internal things that I can't talk about.
  
  
• Apple: Developer Tools Group
  Director and Architect, Low-Level Tools
  September 2011 - January 2013

  This timeframe has included numerous technical and team achievements across a wide range of domains. For example:

  • Apple shipped the Mac OS X 10.8 and iOS 6 releases, and they were built with Clang - llvm-gcc is obsolete, and GCC is long gone.
  • We invested major effort into compiler implementation and tuning for the custom Apple CPU design known as the "Apple A6". The exceptional CPU performance of the iPhone 5 was a result of a joint effort between the Apple silicon and LLVM teams.
  • I personally drove LLDB to production quality and to become the default debugger in Xcode.
  • I drove the new "Objective-C Literal Syntax" language extensions, making many common situations in Objective-C much more syntactically elegant.
  • We shipped Xcode 4.3, 4.4, and 4.5 releases, and I was a key part of the high level feature planning and decision processes that defined the features and shaped the releases.
  
  
• Apple: Developer Tools Group
  Senior Manager and Architect, Low-Level Tools
  June 2010 - September 2011

  I managed the teams responsible for compilers, the LLDB debugger, Objective-C and C++ runtimes, assembler, linker, dynamic loader, etc. I am continuing my work improving the Apple developer tools, and continue to contribute daily to the open source LLVM technologies. During this time period my team switched Mac OS/X Lion and iOS5 to build with llvm-gcc and clang (off of GCC 4.2) and oversaw the final release of Xcode 4.0 in March (as well as subsequent updates).

  Xcode 4.2 was a specific achievement in that it is the first release where all of its compilers are LLVM-based (GCC 4.2 is no longer included). Xcode 4.2 also includes the "Automatic Reference Counting (ARC) Objective-C language feature (see also wikipedia). ARC has revolutionized Objective-C programming by automating memory management without the runtime overhead of a garbage collector. I personally defined and drove this feature late in the schedule of iOS5 and Lion. This is notable for the short schedule for the project, the extensive cross-functional work required, and the extensive backwards compatibility issues that had to be addressed (making it a very technically complex problem).

• Apple: Developer Tools Group
  Senior Manager of Compilers and Low-Level Tools, Compiler Architect
  September 2009 - June 2010

  My work in this time period culminated in the release of the Xcode 4 preview at WWDC, which included a preview release of Clang C++ support, a new C++ Standard Library, a much faster and memory efficient system linker, a new X86 assembler (which is integrated into the clang compiler, providing faster compile times), and countless smaller improvements throughout the toolchain.

  Xcode 4 itself now features deep integration of the Clang parser for code completion, syntax highlighting, indexing, live warning and error messages, and the new 'Fix-It' feature in which the compiler informs the UI how to automatically corrects small errors. LLVM-GCC is the default compiler in Xcode 4.

  The Xcode 4 preview also includes the first public release of LLDB to which I served as a consultant and contributed directly to turning it into an open source project.

• Apple: Developer Tools Group
  Manager of Compilers and Low-Level Tools, Compiler Architect
  July 2008 - September 2009

  In this time period, I was a second level manager running the teams responsible for Clang, LLVM, GCC, and other parts of the Apple toolchain (assembler, linker, etc). I directly managed the Clang team, contributed daily to both the Clang and LLVM projects, and continued in my role as compiler architect and lead on the Open Source LLVM/Clang projects.

  During this period my team brought Clang 1.0 to production quality as a brand new C and Objective-C compiler for X86-32 and X86-64. We also productized and shipped the Xcode static analyzer, a new compiler-rt library (which replaced libgcc in Snow Leopard) and many enhancements to existing components in the operating system.

• Apple: Developer Tools Group
  LLVM Compiler Group Manager and Compiler Architect
  December 2006 - July 2008

  In this time period, my group expanded use of LLVM within Apple, supported new clients, built new features, and extended LLVM in many ways. We shipped llvm-gcc 4.2 in the Xcode 3.1 and major improvements for it in the Xcode 3.1.1 release.

  In addition to llvm-gcc, much of the work during this time was focused on Mac OS 10.6 development. I made major contributions to design and implementation of the "Blocks" language feature as well as to the architecture and design of the language and compiler aspects of the OpenCL GPGPU technology.

  Finally, during this period I architected and started implementation of a suite of front-end technologies based on LLVM, named "Clang".

• Apple Computer Inc: Developer Tools Group
  Senior Compiler Engineer and Tech Lead
  June 2005 - December 2006

  I drove LLVM productization, features and applications at Apple. LLVM link-time optimization support is now integrated into the Apple system linker, and LLVM is used by the Apple OpenGL group for several different purposes. My main contributions during this time was a new llvm-gcc4 front-end, significant improvements to the X86 and PowerPC backends, a wide range of optimization improvements and new optimizers, significant improvement to the target-independent code generator, and leadership for the rest of the team.

Graduate School Work

• University of Illinois at Urbana Champaign
  Research Assistant
  Fall 2000 - Spring 2005

  I worked on numerous projects at UIUC, the most important being LLVM and Data Structure Analysis (DSA). At Illinois, I designed and built most of the fundamental aspects of LLVM, establishing the architecture for things to come and building most of the scalar, loop and interprocedural optimizers. I also built most of the target-independent code generator, X86 backend, JIT, llvm-gcc3 front-end, and much more. Finally, I wrote many papers.

• Microsoft Research: Programmer Productivity Research Center
  Research Intern
  Summer 2004

  I worked on the Microsoft Phoenix compiler infrastructure, building an experimental bridge between the Microsoft compiler and the LLVM compiler (which allowed LLVM to compile and run .NET code). In the process, I identified and fixed numerous bugs in the (still in early development) Microsoft compiler.

IBM NUMA-Q / Sequent Computer Systems:

• Operating Systems Group
  Software Engineer Contractor
  May '00 - Aug '00

  I virtualized the Linux Kernel to run as a user-level application under the Dynix/PTX operating system. This provided 100% compatibility with existing Linux binaries, but this project was never productized.

• Compilers & Tools Group
  Software Engineer Contractor
  May '99 - Dec '99

  I was involved with the 4.5 release of Sequent's PTX OS, which added kernel threads. I was primarily involved porting the Java Virtual Machine from user-level threads to native threads, but also debugged many kernel issues in the pthreads implementation. I also added thread awareness to the system debugger.

• Operating Systems Group
  Software Engineer Intern
  Jan '99 - Apr '99

  I worked 16 hrs/wk developing an online remote kernel debugger based on GDB.

• Compilers & Tools Group
  Software Engineer Intern
  May-Aug, Dec '98

  My primary work was to port Sun's Java Virtual Machine to the Dynix/PTX OS. This involved work in both C & Java, in systems as varied as user-level threads, garbage collection, and asynchronous I/O.

Education

University of Illinois, Urbana-Champaign - Urbana, Illinois - GPA: 4.0

• Ph.D. Computer Science: Spring 2002 - Spring 2005
  Thesis: "Macroscopic Data Structure Analysis and Optimization"
• M.S. Computer Science: Fall 2000 - Fall 2002
  Thesis: "LLVM: An Infrastructure for Multi-Stage Optimization"

University of Portland - Portland, Oregon - GPA: 3.9

• B.S. Computer Science: Fall 1996 - Spring 2000

Invited Talks

1. "Concurrency with Chris Lattner", discussing my proposed concurrency model for Swift 6
   Swift Unwrapped Podcast, September 4, 2017
2. "WWDC 2017 Swift Panel"
   Realm WWDC Panel, June 8, 2017.
3. "Interview: My personal backstory"
   SwiftCoders Podcast, Episode 37, January 23, 2017.
4. "Interview: Swift history and design" (transcript)
   Accidental Tech Podcast, Episode 205, January 19, 2017.
5. "Swift: Opportunities for Language and Compiler Research"
   IBM PL Day 2016, Yorktown Heights, NY, December 2016.
6. "Swift 3 Introduction, Platform State of the Union" - Section starts at 16:30
   2016 Apple World Wide Developer Conference (WWDC), San Francisco, CA, June 2016.
7. "What's New in Swift 3" - Middle third of the talk
   2016 Apple World Wide Developer Conference (WWDC), San Francisco, CA, June 2016.
8. "Keynote: Swift & Xcode Playgrounds Demo"
   IBM Interconnect 2016, Las Vegas, NV, February 2016.
9. "Swift's High-Level IR: A Case Study of Complementing LLVM IR with Language-Specific Optimization - second half of talk
   2015 LLVM Developer's Meeting, San Jose, CA, November 2015.
10. Swift 2 Introduction, Platform State of the Union - Section starts at 56:40
    2015 Apple World Wide Developer Conference (WWDC), San Francisco, CA, June 2015.
11. What's new in Swift 2 - First half of talk
    2015 Apple World Wide Developer Conference (WWDC), San Francisco, CA, June 2015.
12. "Apple Keynote, Swift Launch Demo - Swift Launch, starts at 103:50 my demo starts at 107:15
    2014 Apple World Wide Developer Conference (WWDC), San Francisco, CA, June 2014.
13. "LLVM - The Early Days - first half of a talk
    2013 LLVM Developer's Meeting, San Francisco, CA, November 2013.
14. "LLVM and Clang - Advancing Compilers and Tools
    Opening Keynote, 2013 Central and Eastern European Software Engineering Conference in Russia (CEE-SECR 2013), Moscow, Russia, October 2013.
    Selected as the best invited talk by conference attendees.
15. "What's New in Xcode 5
    2013 Apple World Wide Developer Conference (WWDC), San Francisco, CA, June 2013.
16. "Developer Tools Kickoff" (shared talk)
    2012 Apple World Wide Developer Conference (WWDC), San Francisco, CA, June 2012.
17. "Increasing Industry Impact of Compiler Optimization Research"
    Opening Keynote, 2012 International Symposium on Code Generation and Optimization (CGO'12), San Jose, CA, April 2012.
18. "LLVM and Clang: Advancing Compiler Technology
    Keynote, Free and Open Source Developers' European Meeting (FOSDEM'11), Brussels, Belgium, February 2011.
19. "What's New in the LLVM Compiler" (shared talk)
    2010 Apple World Wide Developer Conference (WWDC), San Francisco, CA, June 2010.
20. "State of Clang" (shared talk) and several other pieces of the meeting, such as the introduction, open discussion forum, etc.
    LLVM Developer Meeting, Cupertino, CA, Oct 2009.
21. "Developer Tools State of the Union" (shared talk)
    2009 Apple World Wide Developer Conference (WWDC), San Francisco, CA, June 2009.
22. "Compiler State of the Union" (shared talk)
    2009 Apple World Wide Developer Conference (WWDC), San Francisco, CA, June 2009.
23. "Introduction to the LLVM Compiler System"
    Plenary Talk, ACAT 2008: Advanced Computing and Analysis Techniques in Physics Research, Erice, Sicily, Italy, November 2008.
24. "Compiler State of the Union" (shared talk)
    2008 Apple World Wide Developer Conference (WWDC), San Francisco, CA, June 2008.
25. "LLVM Compiler In Depth" (shared talk)
    2008 Apple World Wide Developer Conference (WWDC), San Francisco, CA, June 2008.
26. "LLVM and Clang: Next Generation Compiler Technology"
    BSDCan 2008, Ottawa, Canada, May 16-17, 2008.
27. "The LLVM Compiler System"
    2007 O'Reilly Open Source Convention, Portland, OR, July 2007.
28. "LLVM 2.0 and Beyond!"
    Google Tech Talk, Mountain View, CA, July 25, 2007.
29. "Taking Advantage of Compiler Advances" (shared talk)
    2007 Apple World Wide Developer Conference (WWDC), San Francisco, CA, June 2007.
30. "LLVM in OpenGL and for Dynamic Languages" (and several others)
    LLVM Developer Meeting, Cupertino, CA, May 2007.
31. "The LLVM Compiler System"
    2007 Bossa Conference on Open Source, Mobile Internet and Multimedia, Recife, Brazil, March 2007.
32. "Introduction to the LLVM Compiler Infrastructure"
    2006 Itanium Conference and Expo, San Jose, California, April 2006.

Writen Work and Publications

Here are some of the more interesting things I've written:

• In 2011, I wrote a chapter on LLVM for "The Architecture of Open Source Applications," a book on software design. It explains traditional compiler design, what makes LLVM different, how library-based design impacts applicability of the code, and how some simple optimizations work.
• May 2011: I wrote a treatise about undefined behavior in C, describing how it works, why and why it is so problematic. I wrote this when working on Swift, and because I was tired of explaining the same old problems in C over and over.

Since joining industry, I rarely take time to write papers about my work, preferring instead to focus on building new great things. That said, LLVM is widely used as a basis for many current and past research projects by other people.

1. "Making Context-sensitive Points-to Analysis with Heap Cloning Practical For The Real World"
   Chris Lattner, Andrew Lenharth, and Vikram Adve
   PLDI 2007, San Diego, CA, June 2007
2. "Automatic Pool Allocation: Improving Performance by Controlling Data Structure Layout in the Heap"
   Chris Lattner & Vikram Adve
   PLDI 2005, Chicago, IL, June 2005.
   Awarded PLDI 2005 Best Paper Award
3. "Automatic Pointer Compression for Linked Data Structures"
   Chris Lattner & Vikram Adve
   ACM SIGPLAN 2005 Workshop on Memory System Performance (MSP'05) Chicago, IL, June 2005.
4. "Memory Safety Without Runtime Checks or Garbage Collection"
   Dinakar Dhurjati, Sumant Kowshik, Vikram Adve & Chris Lattner
   2005 Transactions in Embedded Computing Systems (TECS'05)
   Journal Publication
5. "The LLVM Compiler Framework and Infrastructure Tutorial"
   Chris Lattner & Vikram Adve
   LCPC'04 Workshop on Compiler Research Infrastructures, West Lafayette, Indiana, Sep. 2004.
6. "LLVM: An Aggressive Compilation Framework for Life-Long Program Analysis and Transformation"
   Chris Lattner & Vikram Adve
   CGO 2004, San Jose, CA, March 2004.
   Best Student Presenter Award
   Test of Time Award for the most influential paper of CGO 2004 (awarded at CGO 2014).
7. "LLVA: A Low-level Virtual Instruction Set Architecture"
   Vikram Adve, Chris Lattner, Michael Brukman, Anand Shukla, & Brian Gaeke
   MICRO-36 2003, San Diego, CA, December 2003.
8. "Memory Safety Without Runtime Checks or Garbage Collection"
   Dinakar Dhurjati, Sumant Kowshik, Vikram Adve, & Chris Lattner
   Proc. Languages Compilers and Tools for Embedded Systems 2003 (LCTES 03), San Diego, CA, June 2003.
9. "Architecture For a Next-Generation GCC"
   Chris Lattner & Vikram Adve
   First Annual GCC Developers' Summit, Ottawa, Canada, May 2003.
10. "Automatic Pool Allocation for Disjoint Data Structures"
    Chris Lattner & Vikram Adve
    ACM SIGPLAN 2002 Workshop on Memory System Performance (MSP'02), Berlin, Germany, June 2002.
11. "Developing a Graphical Robotics Simulator"
    Ming-Shu Hsu & Chris Lattner
    IASTED International Conference, Modeling & Simulation (MS'99)

Other Interests and Activities

In addition to technical activities:

• I am married (to Tanya), have two kids (Zac and Riley), and three dog (Zoey, Copper, Annie).
• I co-founded and contribute to the Swift Community Podcast in my spare time.
• I enjoy woodworking, downhill skiing, swimming, and walking our dogs.
• I was a competitive fencer and was president of the University of Illinois Classical Fencing club. I taught an introduction to fencing class in 2003-2004, with a class of ~15 people.