nikic's Blog

This is my second year working on LLVM at Red Hat. Similar to last year’s blog post, I want to summarize some of the things I’ve worked on this year.
Opaque pointers
The opaque pointer migration is the main task I worked on last year, and it carried substantially over into this year as well....

Unlike miscompilations, reducing compiler crashes to a minimal test case is a straightforward process, which always follows the same general approach, and is supported by high-quality reduction tooling.
However, I don’t think the entire process (and some of the edge cases) is documented anywhere, so I am trying to remedy that....

Scalar evolution (SE or SCEV) models how values change inside loops. It can answer questions like “how many iterations does this loop perform?” and “What value does this variable have on the Nth iteration?” As such, it is the main building block for...

Conceptually, the backend of an optimizing compiler is supposed to be the part that performs CPU architecture specific optimizations, while the middle-end is target-independent. In reality, the middle-end does need to take certain properties of the target...