[Bug tree-optimization/106070] [13 Regression] Wrong code with -O1 since r13-469-g9a53101caadae1b5

[rearnsha at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106070

--- Comment #10 from Richard Earnshaw <rearnsha at gcc dot gnu.org> ---
the testcase in the committed patch, that is.