[Bug tree-optimization/77544] [6/7 Regression] segfault at -O0 - infinite loop in simplification

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77544

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
The issue is inconsistent folding done by associates split_tree when facing
~X vs -X - 1.  I have a patch.