[Bug middle-end/104885] ICE in compiling new test case g++.dg/other/pr84964.C after r12-7607-ga717376e99fb33

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104885

--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Roger Sayle <sayle@gcc.gnu.org>:

https://gcc.gnu.org/g:41d1f11f5f693a2a06c65c9467a28dfeb02aed85

commit r12-7833-g41d1f11f5f693a2a06c65c9467a28dfeb02aed85
Author: Roger Sayle <roger@nextmovesoftware.com>
Date:   Sat Mar 26 08:10:27 2022 -1000

    PR middle-end/104885: Fix ICE with large stack frame on powerpc64.

    My recent testcase for PR c++/84964.C stress tests the middle-end by
    attempting to pass a UINT_MAX sized structure on the stack.  Although
    my fix to PR84964 avoids the ICE after sorry on x86_64 and similar
    targets, a related issue still exists on powerpc64 (and similar
    ACCUMULATE_OUTGOING_ARGS/ARGS_GROW_DOWNWARD targets) which don't
    issue a "sorry, unimplemented" message, but instead ICE elsewhere.

    After attempting several alternate fixes, the simplest solution is
    to just defensively check in mark_stack_region_used that the upper
    bound of the region lies within the allocated stack_usage_map
    array, which is of size highest_outgoing_arg_in_use.  When this isn't
    the case, the code now follows the same path as for variable sized
    regions, and uses stack_usage_watermark rather than a map.

    2022-03-26  Roger Sayle  <roger@nextmovesoftware.com>

    gcc/ChangeLog
            PR middle-end/104885
            * calls.cc (mark_stack_region_used): Check that the region
            is within the allocated size of stack_usage_map.