Free Pascal Reference guide Reference guide for Free Pascal, version 3.2.2 Document version 3.2.2 May 2021 Michaël Van Canneyt Contents 1 Pascal Tokens 12 1.1 Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182 13.1 Allowed C constructs in Free Pascal . . . . . . . . . . . . . . . . . . . . . . . . . . 187 14.1 Unsupported modifiers . . . as the reference for the Pascal language as implemented by the Free Pascal compiler. It describes all Pascal constructs supported by Free Pascal, and lists all supported data types. It does not, however

today • Very quick review of concurrency and lock-free programming • Review the “bread and butter” of lock-free design patterns • Define wait-free algorithms, understand the definition and practical an elegant wait-free algorithm and wait-free design • Some simple benchmarks Some assumed knowledge • You know what std::atomic does and what it is used for • You’ve heard of lock-free programming and Obstruction free (progress in isolation): A single thread executed in isolation will complete the operation in a bounded number of steps. • Obstruction-free algorithms are immune to deadlock • Lock free (at

CPPCON 2020 / CPPCON 2020 / MACRO-FREE TESTING MACRO-FREE TESTING WITH C++20 WITH C++20 | | | | HTTPS://BOOST-EXT.GITHUB.IO/UT/CPPCON-2020 HTTPS://BOOST-EXT.GITHUB.IO/UT/CPPCON-2020 KRIS@JUSIAK SINGLE (2K LOC) WITH NO EXTERNAL DEPENDENCIES (2K LOC) WITH NO EXTERNAL DEPENDENCIES MACRO-FREE (✔ ) MACRO-FREE (✔ ) (*) LIMITATIONS MAY APPLY (*) LIMITATIONS MAY APPLY HTTPS://GITHUB.COM/BOOST-EXT/UT SINGLE (2K LOC) WITH NO EXTERNAL DEPENDENCIES (2K LOC) WITH NO EXTERNAL DEPENDENCIES MACRO-FREE (✔ ) MACRO-FREE (✔ ) FEATURES ( FEATURES ( , , , , , , , , , , , , , , ) (*) LIMITATIONS MAY APPLY

Free Pascal User’s Guide User’s Guide for Free Pascal, Version 3.2.2 Document version 3.2.2 May 2021 Michaël Van Canneyt Florian Klämpfl Contents 1 Introduction 7 1.1 About this document . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 7 Porting and portable code 95 7.1 Free Pascal compiler modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 7.2 Turbo Pascal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 8 Utilities that come with Free Pascal 106 8.1 Demo programs and examples . . . . . . . . . . . . . . . . . . . . . . . . . . .

Free Pascal Programmer’s Guide Programmer’s Guide for Free Pascal, Version 3.2.2 Document version 3.2.2 May 2021 Michaël Van Canneyt Contents 1 Compiler directives 14 1.1 Introduction . . . . . . Register table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 6.3 Calling mechanisms in Free Pascal . . . . . . . . . . . . . . . . . . . . . . . . . . . 86 6.4 Stack frame when calling a nested OF TABLES About this document This is the programmer’s manual for Free Pascal. It describes some of the peculiarities of the Free Pascal compiler, and provides a glimpse of how the compiler generates

head) ● Busy polling on full / empty vs. sync using system calls ● Blocking / non blocking / wait-free ● Data ownership or just value propagation 13 CppCon 2024 | Erez Strauss | Lockfree, MPMC Queue instructions ● std::atomic - provides load / store / compare_exchange ● std::atomic::is_always_lock_free ● Load and Store of aligned 8 bytes ● CAS ( old-expected, new-value ) - atomic Compare And Swap

reliable sources such as Boost.Lockfree? ● Writing such a fifo is a fairly gentle introduction to lock free programming. ● There are some interesting performance optimizations that can be made. ● You may net/home/lock-free-algorithms/queues/unbounded-spsc-queue https://www.dpdk.org/ 3● Single producer: one producer (aka writer) thread ● Single consumer: one consumer (aka reader) thread ● Lock-free: it doesn’t doesn’t use mutex locks. At any point of time, some thread will make progress. ● Wait-free: each thread moves forward regardless of other threads. ● [Circular] Fifo [or Queue]: a single, fixed-size buffer

Deferred reclamation, i.e., garbage collection in C++ Some assumed knowledge • You’ve heard of lock-free programming and know what a compare_exchange is • You know roughly what atomic does and what it is Deferred reclamation, i.e., garbage collection in C++ Some assumed knowledge • You’ve heard of lock-free programming and know what a compare_exchange is • You know roughly what atomic does and what it is danielanderson.net std::atomic How many lines does it take to implement a lock-free & memory-safe stack? template struct Stack { struct Node { T t; shared_ptr

- Enroll in our Godot Game Development Mini-Degree to master 2D and 3D game development with the free, open-source Godot game engine © Zenva Pty Ltd 2020. All rights reserved Godot Game - Enroll in our Godot Game Development Mini-Degree to master 2D and 3D game development with the free, open-source Godot game engine © Zenva Pty Ltd 2020. All rights reserved Before diving into this - Enroll in our Godot Game Development Mini-Degree to master 2D and 3D game development with the free, open-source Godot game engine © Zenva Pty Ltd 2020. All rights reserved Table of Contents