News

Building a safety critical memory manager for self driving cars -- Illya Rudkin

What does it take to build a C++ memory manager for safety critical applications such as autonomous vehicles?

Codeplay's Safety-Critical Memory Manager

by Illya Rudkin

From the article

In my experience, when implementing an application, the memory management part of its design is very often overlooked. That is also the case when considering the design for a Safety-Critical (SC) system. This blog post talks about why a memory manager should be considered in the design, especially for an SC system, and why the designers of such systems should consider implementing it first, before doing anything else.

Codeplay has created a Safety-Critical Memory Manager (SCMM) as part of its strategy to build an SC tool set, including implementations of open standards (such as OpenCL) for building artificial intelligence in automotive systems. We believe that an SCMM is a fundamental foundation stone to help us achieve and verify the safety goals for our systems in different problem domains.

 

A “sorted view”--Nick Athanasiou

Sorting can be done many ways.

A “sorted view”

by Nick Athanasiou

From the article:

This installment elaborates on the creation of a “sorted_view” utility. The “References” section contains links to the complete code; throughout the article, we provide demos and snippets to showcase and explain the implementations. The section on modernizing the code contains real world applications of the following C++17 features:

  1. structured bindings
  2. template argument deduction for class templates

Order Your Members

How ordering members can impact performance.

Order Your Members

by Jonas Devlieghere

From the article:

The article highlights the impact that different choices regarding the ordering of members in a struct can have on the performance of your code. A lot can be achieved by taking into account some general guidelines.

(Not) detecting bugs--Andrzej Krzemieński

Undefined behaviour can be dangerous.

(Not) detecting bugs

by Andrzej Krzemieński

From the article:

The following code contains a bug. A developer has spent quite some time looking for the source. The intent of this code is to iterate over two vectors simultaneously, from the first up to the one-before-last element. Thus the most interesting tools that will be employed will be boost::zip_iterator and std::prev.

#include <boost/iterator/zip_iterator.hpp>
#include <boost/tuple/tuple.hpp>
#include <vector>

using zip_iter = boost::zip_iterator<
                   boost::tuple<
                     std::vector<int>::iterator,
                     std::vector<int>::iterator
                   >
                 >;
int main()
{
  std::vector<int> v1 = {1, 2, 3, 4, 0};
  std::vector<int> v2 = {2, 3, 5, 7, 0};
    
  zip_iter beg {boost::make_tuple(v1.begin(), v2.begin())};
  zip_iter end {boost::make_tuple(v1.end(), v2.end())};
  
  auto process = [](zip_iter::reference){};
  std::for_each(beg, std::prev(end), process);
}

Add a const here, delete a const there…--Bruce Dawson

Why constness is important in one article. Can be even better with constexpr.

Add a const here, delete a const there…

by Bruce Dawson

From the article:

I just completed a series of changes that shrunk the Chrome browser’s on-disk size on Windows by over a megabyte, moved about 500 KB of data from its read/write data segments to its read-only data segments, and reduced its private working set by about 200 KB per-process. The amusing thing about this series of changes is that they consisted entirely of removing const from some places, and adding const to others. Compilers be weird...