Krister Walfridsson’s old blog

I have started blogging again! But I am too annoyed at Blogger, so the new posts will be published in my new blog: https://kristerw.github.i...

Software inefficiencies often show up as wasteful memory operations, and many research tools can detect various cases of this. One such too...

LLVM optimizes power sums, such as int sum(int count) { int result = 0; for (int j = 0; j < count; ++j) result += j*j; ret...

GCC 1.27 was released in 1988 and is the first version of GCC supporting the x86 CPU. I thought it would be fun to make it work on my deskt...

I have done some Commodore 64 programming over the holidays. The C64 is old , but I think there are things that can be learned from dealing...

The performance of programs depend surprisingly much on things that “should not” matter (such as the order files are passed to the linker )...

Inlining is important for C++ performance, but the compiler must be careful not to increase the code size too much. GCC’s inlining process ...

It is easy to use quick-bench to benchmark small C++ functions, but it is hard to ensure they are measuring what is intended. Take this b...