[Bug tree-optimization/100061] Comparison guarding undefined behaviour disappears

[rguenth at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100061

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
It needs quite some refactoring to distinguish the short-circuiting case from
the non-short-circuiting one.

 if (b > c + 1)
   if (b > c)

is OK to combine while

 if (b > c)
   if (b > c + 1)

is not.