https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103554
--- Comment #7 from Avi Kivity <avi at scylladb dot com> --- Sorry, I was unclear. That's the entire program with a huge number of slp opportunities. Each iteration in the program is ~40k instructions. It's not directly related to the test case, which is artificial, and arose from me exploring the differences between gcc and clang code generation. It does demonstrate that clang's slp is counterproductive. I promise to repeat the experiment with gcc once it stops ICEing.
