[Bug rtl-optimization/85072] g++ -O1 consumes all memory

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85072

--- Comment #7 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Vladimir Makarov <vmakarov@gcc.gnu.org>:

https://gcc.gnu.org/g:43afcb3a83c3648141285d80cd3d8a562047fb43

commit r16-5876-g43afcb3a83c3648141285d80cd3d8a562047fb43
Author: Vladimir N. Makarov <vmakarov@redhat.com>
Date:   Wed Dec 3 13:42:41 2025 -0500

    [PR85072, LRA]: Set a limit for considering other reload pseudo preferences

    Compilation of test in PR85072 takes a lot of time and memory, e.g. 17
    minutes and 23 GB memory on AMD 9900X.  The function in question has one
million
    program points and one million pseudos. The culprits are
    live_reload_and_inheritance_pseudos bitmaps which are used to consider
    other reload pseudo preferences when assigning a register to a given
    pseudo.  The patch introduces a constraint regarding when those
    preferences are considered.  The patch decreases compilation time to
    about 10 minutes and memory consumption to about 2GB.

    gcc/ChangeLog:

            PR rtl-optimization/85072
            * lra-assigns.cc (init_live_reload_and_inheritance_pseudos):
            Improve calculation of live_reload_and_inheritance_pseudos and set
            a constraint to do this.
            * params.opt
            (lra-max-pseudos-points-log2-considered-for-preferences): New.
            * doc/invoke.texi
            (lra-max-pseudos-points-log2-considered-for-preferences): Document
            it.