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What Is LLVM? and a Status Update
What is LLVM? And a Status Update. Approved for public release Hal Finkel Leadership Computing Facility Argonne National Laboratory Clang, LLVM, etc. ✔ LLVM is a liberally-licensed(*) infrastructure for creating compilers, other toolchain components, and JIT compilation engines. ✔ Clang is a modern C++ frontend for LLVM ✔ LLVM and Clang will play significant roles in exascale computing systems! (*) Now under the Apache 2 license with the LLVM Exception LLVM/Clang is both a research platform and a production-quality compiler. 2 A role in exascale? Current/Future HPC vendors are already involved (plus many others)... Apple + Google Intel (Many millions invested annually) + many others (Qualcomm, Sony, Microsoft, Facebook, Ericcson, etc.) ARM LLVM IBM Cray NVIDIA (and PGI) Academia, Labs, etc. AMD 3 What is LLVM: LLVM is a multi-architecture infrastructure for constructing compilers and other toolchain components. LLVM is not a “low-level virtual machine”! LLVM IR Architecture-independent simplification Architecture-aware optimization (e.g. vectorization) Assembly printing, binary generation, or JIT execution Backends (Type legalization, instruction selection, register allocation, etc.) 4 What is Clang: LLVM IR Clang is a C++ frontend for LLVM... Code generation Parsing and C++ Source semantic analysis (C++14, C11, etc.) Static analysis ● For basic compilation, Clang works just like gcc – using clang instead of gcc, or clang++ instead of g++, in your makefile will likely “just work.” ● Clang has a scalable LTO, check out: https://clang.llvm.org/docs/ThinLTO.html 5 The core LLVM compiler-infrastructure components are one of the subprojects in the LLVM project. These components are also referred to as “LLVM.” 6 What About Flang? ● Started as a collaboration between DOE and NVIDIA/PGI. -
A DSL for Resource Checking Using Finite State Automaton-Driven Symbolic Execution Code
Open Comput. Sci. 2021; 11:107–115 Research Article Endre Fülöp and Norbert Pataki* A DSL for Resource Checking Using Finite State Automaton-Driven Symbolic Execution https://doi.org/10.1515/comp-2020-0120 code. Compilers validate the syntactic elements, referred Received Mar 31, 2020; accepted May 28, 2020 variables, called functions to name a few. However, many problems may remain undiscovered. Abstract: Static analysis is an essential way to find code Static analysis is a widely-used method which is by smells and bugs. It checks the source code without exe- definition the act of uncovering properties and reasoning cution and no test cases are required, therefore its cost is about software without observing its runtime behaviour, lower than testing. Moreover, static analysis can help in restricting the scope of tools to those which operate on the software engineering comprehensively, since static anal- source representation, the code written in a single or mul- ysis can be used for the validation of code conventions, tiple programming languages. While most static analysis for measuring software complexity and for executing code methods are designed to detect anomalies (called bugs) in refactorings as well. Symbolic execution is a static analy- software code, the methods they employ are varied [1]. One sis method where the variables (e.g. input data) are inter- major difference is the level of abstraction at which the preted with symbolic values. code is represented [2]. Because static analysis is closely Clang Static Analyzer is a powerful symbolic execution related to the compilation of the code, the formats used engine based on the Clang compiler infrastructure that to represent the different abstractions are not unique to can be used with C, C++ and Objective-C. -
SMT-Based Refutation of Spurious Bug Reports in the Clang Static Analyzer
SMT-Based Refutation of Spurious Bug Reports in the Clang Static Analyzer Mikhail R. Gadelha∗, Enrico Steffinlongo∗, Lucas C. Cordeiroy, Bernd Fischerz, and Denis A. Nicole∗ ∗University of Southampton, UK. yUniversity of Manchester, UK. zStellenbosch University, South Africa. Abstract—We describe and evaluate a bug refutation extension bit in a is one, and (a & 1) ˆ 1 inverts the last bit in a. for the Clang Static Analyzer (CSA) that addresses the limi- The analyzer, however, produces the following (spurious) bug tations of the existing built-in constraint solver. In particular, report when analyzing the program: we complement CSA’s existing heuristics that remove spurious bug reports. We encode the path constraints produced by CSA as Satisfiability Modulo Theories (SMT) problems, use SMT main.c:4:12: warning: Dereference of null solvers to precisely check them for satisfiability, and remove pointer (loaded from variable ’z’) bug reports whose associated path constraints are unsatisfi- return *z; able. Our refutation extension refutes spurious bug reports in ˆ˜ 8 out of 12 widely used open-source applications; on aver- age, it refutes ca. 7% of all bug reports, and never refutes 1 warning generated. any true bug report. It incurs only negligible performance overheads, and on average adds 1.2% to the runtime of the The null pointer dereference reported here means that CSA full Clang/LLVM toolchain. A demonstration is available at claims to nevertheless have found a path where the dereference https://www.youtube.com/watch?v=ylW5iRYNsGA. of z is reachable. Such spurious bug reports are in practice common; in our I. -
Openbsd Gaming Resource
OPENBSD GAMING RESOURCE A continually updated resource for playing video games on OpenBSD. Mr. Satterly Updated August 7, 2021 P11U17A3B8 III Title: OpenBSD Gaming Resource Author: Mr. Satterly Publisher: Mr. Satterly Date: Updated August 7, 2021 Copyright: Creative Commons Zero 1.0 Universal Email: [email protected] Website: https://MrSatterly.com/ Contents 1 Introduction1 2 Ways to play the games2 2.1 Base system........................ 2 2.2 Ports/Editors........................ 3 2.3 Ports/Emulators...................... 3 Arcade emulation..................... 4 Computer emulation................... 4 Game console emulation................. 4 Operating system emulation .............. 7 2.4 Ports/Games........................ 8 Game engines....................... 8 Interactive fiction..................... 9 2.5 Ports/Math......................... 10 2.6 Ports/Net.......................... 10 2.7 Ports/Shells ........................ 12 2.8 Ports/WWW ........................ 12 3 Notable games 14 3.1 Free games ........................ 14 A-I.............................. 14 J-R.............................. 22 S-Z.............................. 26 3.2 Non-free games...................... 31 4 Getting the games 33 4.1 Games............................ 33 5 Former ways to play games 37 6 What next? 38 Appendices 39 A Clones, models, and variants 39 Index 51 IV 1 Introduction I use this document to help organize my thoughts, files, and links on how to play games on OpenBSD. It helps me to remember what I have gone through while finding new games. The biggest reason to read or at least skim this document is because how can you search for something you do not know exists? I will show you ways to play games, what free and non-free games are available, and give links to help you get started on downloading them. -
DVD-Libre 2005-04 Y 2 Pr W W Pr B - 3 T T T T S De Ca SI 5 Sc Re Ra Q 1 Po 3 Ph I Sa Dic Dic 2 4 W Ex ( H N C T
(continuación) - CDCheck 3.1.4.0 - CDex 1.51 - Celestia 1.3.2 - Centarsia 1.3 - Chain Reaction - Check4me 2.03 - Checky 2.5 - Chomp 1.4.5 - ClamWin 0.83 - Clan Bomber 1.05 - Cobian Backup 6.1.1.264 - Cobian Internet Tools 1.0.0.10 - ColorCop 5.3 - ColorWiz 1.0 - Combinaisons Junior Plus 2.70 - Continental 2.1 - Crack Attack! 1.1.08 - Crimson Editor 3.70 - CubeTest 0.9.3 - DBDesigner 4.0.5.6 - DeepBurner 1.3.6.168 - Deslizzzp 3.3 - Dev-C++ 4.9.9.2 - Dia Win32 0.94 - DirGraph 2.0 - DVD-Libre Disk Imager 1.4 - Domino Puzzle 0.1a - DominOSA 1.71 - DomiSol 1.2 - Doxygen 1.4.1 - Dragonboard 0.8c - Drawing for children 2.0 - DVD Identifier 3.6.2 - e-Counter 3.1.2004 - EasyISO 1.3 - EasyPHP cdlibre.org 1.8 - Eclipse 3.0.1 - Eclipse Language Pack 3.0.x - Eclipse Modeling Framework 2.0.1 - Eclipse Visual Editor 1.0.2 - Emilia Pinball 0.30c - Enigma 0.81 - EQTabla 4.0.050208 - Eraser 5.7 - Everest 2005-04 Dictionary 3.10 beta - Everest Dictionary 3.10 beta Completo - Exact Audio Copy 0.95 prebeta 5 - Exodus 0.9.0.0 - Fall - FileMenu Tools 4.1 - FileZilla 2.2.12a - Find Favorites 1.11 - Firebird 1.5.2 - Flexible Renamer 7.3 - FloboPuyo 0.20 - FolderQuote 1.0 - foobar2000 0.8.3 - FooBilliard 3.0 - Foxit PDF Reader 1.2.0.115 - FractalExplorer 2.02 - FractalForge 2.8.2 - FrameFun 1.0.5.0 - Free Download DVD-Libre es una recopilación de programas para Windows: Manager 1.5.256 - Free Pascal 1.0.10 - FreeCiv 1.14.2 - FreeMind 0.7.1 - Frozen Bubble Enhanced ● libres / gratuitos al menos para uso personal o educativo 1.0 - Gaim 1.1.4 - GanttProject 1.10.3 -
Compiling and Makefiles
Compiling C Programs Makefiles Compiling and Makefiles 2501ICT/7421ICTNathan René Hexel School of Information and Communication Technology Griffith University Semester 1, 2012 René Hexel Compiling and Makefiles Compiling C Programs Makefiles Outline 1 Compiling C Programs 2 Makefiles Using the make Utility Makefiles for Objective-C Code Makefiles for C++ Code René Hexel Compiling and Makefiles Compiling C Programs Makefiles Compiling C Programs Integrated Development Environment (IDE) Eclipse, XCode, Visual C++, Project Center, . Compiles programs at the press of a button (like BlueJ) Often difficult to customise Very rarely support multiple platforms and languages Command Line Requires manual invocation Requires knowledge of command line parameters Can be tedious for large projects Cross-platform and -language compilers (e.g. clang) Makefiles Combine the best of both worlds Recompile a complex project with a simple make command René Hexel Compiling and Makefiles Compiling C Programs Makefiles Getting a Command Line Interface Via Dwarf ssh dwarf.ict.griffith.edu.au using putty (Windows) Via a local Terminal Mac OS X: e.g. Applications / Utilities / Terminal.app Linux: e.g. through the Gnome program menu Windows: e.g. Start / Programs / Programming Tools / GNUstep / Shell ) Enter commands to compile your program Hit Return (or Enter) after every command! René Hexel Compiling and Makefiles Compiling C Programs Makefiles Compiling a C program using clang or gcc Once on the command line change to the directory (folder) your program is in cd /my/example/directory -
ENCM 335 Fall 2018: Command-Line C Programming on Macos
page 1 of 4 ENCM 335 Fall 2018: Command-line C programming on macOS Steve Norman Department of Electrical & Computer Engineering University of Calgary September 2018 Introduction This document is intended to help students who would like to do ENCM 335 C pro- gramming on an Apple Mac laptop or desktop computer. A note about software versions The information in this document was prepared using the latest versions of macOS Sierra version 10.12.6 and Xcode 9.2, the latest version of Xcode available for that version of macOS. Things should work for you if you have other but fairly recent versions of macOS and Xcode. If you have versions that are several years old, though you may experience difficulties that I'm not able to help with. Essential Software There are several key applications needed to do command-line C programming on a Mac. Web browser I assume you all know how to use a web browser to find course documents, so I won't say anything more about web browsers here. Finder Finder is the tool built in to macOS for browsing folders and files. It really helps if you're fluent with its features. Terminal You'll need Terminal to enter commands and look at output of commands. To start it up, look in Utilities, which is a folder within the Applications folder. It probably makes sense to drag the icon for Terminal to the macOS Dock, so that you can launch it quickly. macOS Terminal runs the same bash shell that runs in Cygwin Terminal, so commands like cd, ls, mkdir, and so on, are all available on your Mac. -
Compiling Linux with LLVM
Open Source Open Possibilities Compiling Linux with LLVM Presented by: Mark Charlebois Presentation Date: 06/07/2012 PAGE 1 Open Source Open Possibilities Agenda Why would I want to use Clang to compile Linux? Status updates: cross compiling for ARM with Clang building Linux kernel with Clang running Linux compiled with Clang To do list PAGE 2 Open Source Open Possibilities Open Source Open Possibilities Why Would I Want to Use Clang to Compile Linux? PAGE 3 Open Source Open Possibilities Better Diagnostics $ gcc-4.2 -fsyntax-only t.c t.c:7: error: invalid operands to binary + (have 'int' and 'struct A') $ clang -fsyntax-only t.c t.c:7:39: error: invalid operands to binary expression ('int' and 'struct A') return y + func(y ? ((SomeA.X + 40) + SomeA) / 42 + SomeA.X : SomeA.X); ~~~~~~~~~~~~~~ ^ ~~~~~ See http://clang.llvm.org/diagnostics.html for more examples GCC extensions: all extensions are explicitly recognized as such and marked with extension diagnostics, which can be mapped to warnings, errors, or just ignored. Google builds their products also with Clang just for the better debug output Rich diagnostic output enables auto-generation of patches PAGE 4 Open Source Open Possibilities Fix-it Hints "Fix-it" hints provide advice for fixing small, localized problems in source code. $ clang t.c t.c:5:28: warning: use of GNU old-style field designator extension struct point origin = { x: 0.0, y: 0.0 }; ~~ ^ .x = t.c:5:36: warning: use of GNU old-style field designator extension struct point origin = { x: 0.0, y: 0.0 }; ~~ ^ .y = PAGE 5 -
Code Transformation and Analysis Using Clang and LLVM Static and Dynamic Analysis
Code transformation and analysis using Clang and LLVM Static and Dynamic Analysis Hal Finkel1 and G´abor Horv´ath2 Computer Science Summer School 2017 1 Argonne National Laboratory 2 Ericsson and E¨otv¨osLor´adUniversity Table of contents 1. Introduction 2. Static Analysis with Clang 3. Instrumentation and More 1 Introduction Space of Techniques During this set of lectures we'll cover a space of techniques for the analysis and transformation of code using LLVM. Each of these techniques have overlapping areas of applicability: Static Analysis LLVM Instrumentation Source Transformation 2 Space of Techniques When to use source-to-source transformation: • When you need to use the instrumented code with multiple compilers. • When you intend for the instrumentation to become a permanent part of the code base. You'll end up being concerned with the textual formatting of the instrumentation if humans also need to maintain or enhance this same code. 3 Space of Techniques When to use Clang's static analysis: • When the analysis can be performed on an AST representation. • When you'd like to maintain a strong connection to the original source code. • When false negatives are acceptable (i.e. it is okay if you miss problems). https://clang-analyzer.llvm.org/ 4 Space of Techniques When to use IR instrumentation: • When the necessary conditions can be (or can only be) detected at runtime (often in conjunction with a specialized runtime library). • When you require stronger coverage guarantees than static analysis. • When you'd like to reduce the cost of the instrumentation by running optimizations before the instrumentation is inserted, after the instrumentation is inserted, or both. -
Walnut Creek CDROM Spring 1995 Catalog 1-800-786-9907 • 1-510-674-0821 Fax the Best of Walnut Creek CDROM Is Yours Free*
Walnut Creek CDROM Spring 1995 Catalog 1-800-786-9907 • 1-510-674-0821 Fax The Best of Walnut Creek CDROM is yours Free*. The • You’ll also get fonts, fractals, Best of Walnut Creek CDROM music, clipart, and more. 600 lets you explore in-depth what MegaBytes in total! Walnut Creek CDROM has to offer. • Boot images from our Unix for PC discs so you will With samples from all of our know if your hardware will products, you’ll be able to see boot Slackware Linux or what our CDROM’s will do for FreeBSD you, before you buy. This CDROM contains: • The Walnut Creek CDROM digital catalog - photos and • Index listings of all the descriptions of our all titles programs, photos, and files on all Walnut Creek CDROM If you act now, we’ll include titles $5.00 good toward the purchase of all Walnut Creek CDROM • The best from each disc titles. If you’re only going to including Hobbes OS/2, own one CDROM, this should CICA MS Windows, Simtel be it! March, 1995. MSDOS, Giga Games, Internet Info, Teacher 2000, Call, write, fax, or email your Ultra Mac-Games and Ultra order to us today! Mac-Utilities * The disc is without cost, but the regular shipping charge still applies. • You get applications, games, utilities, photos, gifs, documents, ray-tracings, and animations 2 CALL NOW! 1-800-786-9907 Phone: +1-510-674-0783 • Fax: +1-510-674-0821 • Email: [email protected] • WWW: http://WWW.cdrom.com/ (Alphabetical Index on page 39.) Hi, Sampler - (Best of Walnut Creek) 2 This is Jack and I’ve got another great batch of CICA for Windows 4 Music Workshop 5 CDROM’s for you. -
LLVM Sanitizers
LLVM and the state of sanitizers on BSD Speaker : David Carlier Software engineer living in Ireland, contribute to various opensource projects directly or indirectly related to FreeBSD and OpenBSD mainly, from enterprise solutions to more entertaining ones like video games, contributor LLVM since end of 2017, committer since May 2018. Write time to time for BSDMag. Status on FreeBSD and OpenBSD How it had started ? ● It often starts from “frustration” :-). ● Indeed, after having tried fuzzer under Linux, I realized it was not supported under FreeBSD. ● After this came Xray instrumentation and MemorySanitizer. ● Somewhere in between, started to port UndefinedBehaviorSanitizer, libFuzzer and Xray as well.. ● After getting into enough people's nerves, you get commit access. Where are we ? FreeBSD OpenBSD asan ubsan safestack libFuzzer msan Xray instrumentation libFuzzer Cannot have asan/msan/tsan Xray instrumentation ASLR cannot be disabled Cannot map large regions ubsan (shadow memory) What is fuzzing all about ? ● It is a testing technique, “invented” in late 80'a by Barton Miller, when basically you try to give random data to your software and its dependencies included. ● Inputs source come from what call “corpus” ● It is good to find particular set of bugs, based on input handling basically while trying to cover as much as possible code paths by mutating these inputs. ● Ideally running long, as the data will undergo some “mutation” in the process, as necessary until it crashes eventually. ● Completes traditional unit tests set too. What corpus means ? ● Place holder for inputs, inputs which suit the particular software. ● Let's imagine an image library reader which relies on specific binary format header to recognise if it is png/jpeg and so on. -
Using Clang-Tidy and Clang-Format.Pdf
Using clang-tidy and clang-format Linux Plumbers Conf 2020 - LLVM MC Miguel Ojeda, Nathan Huckleberry What is Clang Tooling? ● Clang is one of the LLVM compiler frontends ● But it is also designed as a platform for building source level tools ○ Syntax checking ○ Automatic fixing of compile errors ○ Code formatting ○ Refactoring ○ Linting ○ Static code analysis ○ … What could the kernel use Clang Tooling for? ● In the kernel we already use a lot of custom tools ○ sparse ○ spatch (Coccinelle) ○ checkpatch.pl ○ … ● Clang Tooling allows us to build more of them ○ Without having to deal with parsing C code ○ With support for all C extensions we use ○ With easy access to the AST (Abstract Syntax Tree) clang-format — What is it? ● A tool to format C-like code ○ Supports different languages ○ Many configurable rules and heuristics ○ Very fast ○ Good enough ● Allows us to spend less time on formatting and reviewing style ● Kernel style already pre-configured for you ○ Overriding the global style for particular subsystems is possible ○ See .clang-format clang-format — Example static inline void cpuhp_lock_acquire ( bool bringup ){ lock_map_acquire ( bringup ? & cpuhp_state_up_map : & cpuhp_state_down_map ); } clang-format — Example static inline void cpuhp_lock_acquire ( bool bringup ){ lock_map_acquire ( bringup ? & cpuhp_state_up_map : & cpuhp_state_down_map ); } static inline void cpuhp_lock_acquire(bool bringup) { lock_map_acquire(bringup ? &cpuhp_state_up_map : &cpuhp_state_down_map); } clang-format — Common use cases ● Re-formatting blocks ○ After indenting to keep line length within the limit ○ After refactoring and moving code around ● Re-formatting full files ● Sorting #includes ● Aligning ○ Variable blocks (on types or on the =) ○ Multi-line macro continuations (\) ● Reflowing comments ● ... clang-format — Kernel use cases ● Re-formatting patches ○ Clang provided script: clang-format-diff.py ○ Useful to spot coding style mistakes, typos, etc.