[Bug target/100782] [11 Regression] sh4 ICEs on -O2 -fPIE -fstack-protector: internal compiler error: in curr_insn_transform, at lra-constraints.c:4132

[slyfox at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100782

--- Comment #4 from Sergei Trofimovich <slyfox at gcc dot gnu.org> ---
Bisected down to r11-4577

commit 44fbc9c6e02ca5b8f98f25b514ed7588e7ba733d
Author: Vladimir N. Makarov <vmakarov@redhat.com>
Date:   Fri Oct 30 15:05:22 2020 -0400

    Take insn scratch RA requirements into account in IRA.

      The patch changes insn scratches which require registers for all
    insn alternatives (in other words w/o X constraint in scratch
    constraint string).  This is done before IRA staring its work.  LRA
    still continue to change the rest scratches (with X constraint and in
    insn created during IRA) into pseudos.  As before the patch at the end
    of LRA work, spilled scratch pseudos (for which X constraint was
    chosen) changed into scratches back.