https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123153
--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Victor Do Nascimento <[email protected]>: https://gcc.gnu.org/g:24bf392581ea6d931afc1e97d90d6a2d6bdaa183 commit r16-6243-g24bf392581ea6d931afc1e97d90d6a2d6bdaa183 Author: Victor Do Nascimento <[email protected]> Date: Wed Dec 17 14:43:41 2025 +0000 Fix profile_probability constructor arg [PR123153] Given that profile probability is computed as an unsigned integer value in the [0, max_probability = (uint32_t) 1 << (n_bits - 2)] range (as opposed to a [0, 1] float), 50/50 likeihoods are encoded as `even()', mapping to `max_probability / 2'. The previous use of 0.5 for an even probability was, as a consequence of the implicit `double' -> `uint32_t' conversion, silently set to 0 by GCC when not using the `-Wconversion' flag. We therefore replace the erroneous `probability (0.5, GUESSED)' initialization with its correct `profile_probability::even ()' counterpart. gcc/ChangeLog: PR tree-optimization/123153 * tree-vect-loop-manip.cc (slpeel_tree_duplicate_loop_to_edge_cfg): use profile_probability::even () for even likelihood.
