[Bug target/97684] New: [11 Regression] ICE in reg_preferred_class, at reginfo.c:789

[asolokha at gmx dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97684

            Bug ID: 97684
           Summary: [11 Regression] ICE in reg_preferred_class, at
                    reginfo.c:789
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---
            Target: powerpc-*-linux-gnu

gcc-11.0.0-alpha20201101 snapshot (g:590febb5f6624f78b36402a7c9a9c318978f1efa)
ICEs when compiling the following testcase w/ -mcpu=power9 -O2
-flive-range-shrinkage -fselective-scheduling -fno-plt:

void
uc (void);

void
hb ()
{
  uc ();
  uc ();
  hb (0);
}

% powerpc-e300c3-linux-gnu-gcc-11.0.0 -mcpu=power9 -O2 -flive-range-shrinkage
-fselective-scheduling -fno-plt -c eij2zyqf.c
during RTL pass: ira
eij2zyqf.c: In function 'hb':
eij2zyqf.c:10:1: internal compiler error: in reg_preferred_class, at
reginfo.c:789
   10 | }
      | ^
0x677ffe reg_preferred_class(int)
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-11.0.0_alpha20201101/work/gcc-11-20201101/gcc/reginfo.c:789
0xbe27e4 update_equiv_regs
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-11.0.0_alpha20201101/work/gcc-11-20201101/gcc/ira.c:3516
0xbe92c2 ira
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-11.0.0_alpha20201101/work/gcc-11-20201101/gcc/ira.c:5498
0xbe92c2 execute
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-11.0.0_alpha20201101/work/gcc-11-20201101/gcc/ira.c:5861