Bicho de sete cabeças. It's not a seven-headed beast. It's not rocket science.Cassio Neri Fast conversion from floating-point numbers CppCon 2024 - Aurora (Independent Researcher)MeMe O Neri's equationMe

Andreas Fertig Write unique code! Fast and small C++ When efficiency matters Presentation Material CppCon, Aurora CO, 2024-09-17© 2024 Andreas Fertig AndreasFertig.com All rights reserved All programs Fertig v1.0 Fast and small C++ 2 Andreas Fertig v1.0 Fast and small C++ 3 Fast and small C++ © 2024 Andreas Fertig https://AndreasFertig.com post@AndreasFertig.com 4Andreas Fertig v1.0 Fast and small std::unique_ptr{fopen("SomeFile.txt", "r"), &fclose}; Andreas Fertig v1.0 Fast and small C++ 5 Fast and small C++ © 2024 Andreas Fertig https://AndreasFertig.com post@AndreasFertig.com

C++ still does not have reflection (introspection): we have to “pick our poison”: • Doing the conversion manually (good luck, you’ll need it) • Automating: • Preprocessing (my poison of choice, twice

Making Games Start Fast A Story About ConcurrencyOnce upon a time, in the early 2000s...We had a small clock speed cap issue...But the solution was easy! Core 🔥🔥🔥 Core 1 Core 2 Core 3 Core 4The Data has to be loaded, but does it have to loaded now? ◉ Our goal is to display the main menu as fast as possible ◉ We can continue loading in background 65Side by Side Comparison 66Loading audio

RapidJSON Boost.JSON simdjson 0 10 20 30 40 Library Time in ms fully validating pull parser fast, O(1) memory usage implicitly define schema github.com/think-cell/think-cell-library Jonathan Müller "Jonathan Müller", "speaker": true, "talks": [ { "title": "Express your expectations", "subtitle": "A fast, compliant JSON pull parser..." } ] } Jonathan Müller — @foonathan Express your expectations CppCon log(object.name) console.log(object.talks[0].subtitle) console.log(object.foo) Jonathan Müller A fast, compliant JSON pull parser for writing robust applications undefined Jonathan Müller — @foonathan

interesting problems • Intra-register sorting • Fast linear median-of-seven filter • Fast small-kernel convolution • Faster (?) UTF-8 to UTF-32 conversion (with AVX2) • No heavy code, but lots of pictures ksize(7) ksize(9) ksize(11) ksize(13) ksize(15)Copyright © 2020 Bob Steagall UTF-8 to UTF-32 Conversion Algorithm 32 CppCon 2020 - Adventures in SIMD ThinkingCopyright © 2020 Bob Steagall K E W B C Bob Steagall K E W B C O M P U T I N G 34 CppCon 2020 - Adventures in SIMD Thinking The Basic Conversion Algorithm (UTF-8 to UTF-32) KEWB_ALIGN_FN std::ptrdiff_t UtfUtils::BasicConvert(char8_t const*

TOFEETPERMINUTE (double)196.9 #define TOMPH (double)2.237 #define TOKPH (double)3.6 // meters to.. conversion #define TONAUTICALMILES (1.0 / 1852.0) #define TOMILES (1.0 / 1609.344) #define TOKILOMETER 0) CppCon 2024: Improving our safety with a quantities and units library The proliferation of conversion macros 13• O�en more than once in the repository #define RAD_TO_DEG (180 / PI) #define RAD_TO_DEG 2957805f CppCon 2024: Improving our safety with a quantities and units library The proliferation of conversion macros 14void DistanceBearing(double lat1, double lon1, double lat2, double

Next C++ Motivation, Existing Practice, Challenges... 21 Quick Start 2 Strong Interfaces 3 As fast as (or even faster) than double 4 User Experience 5 Framework Basics 6 Environment, compatibility 2020 | A Physical Units Library For the Next C++ Agenda 31 Quick Start 2 Strong Interfaces 3 As fast as (or even faster) than double 4 User Experience 5 Framework Basics 6 Environment, compatibility • As fast as double CppCon 2020 | A Physical Units Library For the Next C++ Requirements 10• Compile-time safety • The best possible user experience – compiler errors – debugging • As fast as double

cases this process results in calling the expected overload ○ however, it can get complicated very fast . . . ○ data type conversions can be messy ○ pointer / reference data types may not resolve as expected implicit conversion 22Overload Resolution ● Type Conversions ○ example of an implicit conversion char str[] = "ABC"; int data = str[0]; // data will equal 65 ○ explicit conversion ■ static_cast another type of explicit conversion called an functional cast if (std::string(“root”) == current_directory) { // do something } 23Overload Resolution ● Standard Conversion Categories ○ exact match