[Bug rtl-optimization/94291] New: [10 Regression] ICE: in reg_or_subregno, at jump.c:1928 at -Og

[zsojka at seznam dot cz]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94291

            Bug ID: 94291
           Summary: [10 Regression] ICE: in reg_or_subregno, at
                    jump.c:1928 at -Og
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zsojka at seznam dot cz
  Target Milestone: ---
              Host: x86_64-pc-linux-gnu
            Target: armv7a-hardfloat-linux-gnueabi

Created attachment 48100
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=48100&action=edit
reduced testcase

Compiler output:
$ armv7a-hardfloat-linux-gnueabi-gcc -Og testcase.c
during RTL pass: combine
testcase.c: In function 'foo':
testcase.c:9:1: internal compiler error: in reg_or_subregno, at jump.c:1928
    9 | }
      | ^
0x6a4bbd reg_or_subregno(rtx_def const*)
        /repo/gcc-trunk/gcc/jump.c:1928
0x1983a69 try_combine
        /repo/gcc-trunk/gcc/combine.c:4355
0x1988c63 combine_instructions
        /repo/gcc-trunk/gcc/combine.c:1303
0x1988c63 rest_of_handle_combine
        /repo/gcc-trunk/gcc/combine.c:15059
0x1988c63 execute
        /repo/gcc-trunk/gcc/combine.c:15104
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

$ armv7a-hardfloat-linux-gnueabi-gcc -v
Using built-in specs.
COLLECT_GCC=/repo/gcc-trunk/binary-latest-armv7a-hardfloat/bin/armv7a-hardfloat-linux-gnueabi-gcc
COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-r10-7327-20200323085706-g2fa4b1ffd6e-checking-yes-rtl-df-extra-pr94286-armv7a-hardfloat/bin/../libexec/gcc/armv7a-hardfloat-linux-gnueabi/10.0.1/lto-wrapper
Target: armv7a-hardfloat-linux-gnueabi
Configured with: /repo/gcc-trunk//configure --enable-languages=c,c++
--enable-valgrind-annotations --disable-nls --enable-checking=yes,rtl,df,extra
--with-cloog --with-ppl --with-isl --with-float=hard --with-fpu=vfpv4
--with-arch=armv7-a --with-sysroot=/usr/armv7a-hardfloat-linux-gnueabi
--build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu
--target=armv7a-hardfloat-linux-gnueabi
--with-ld=/usr/bin/armv7a-hardfloat-linux-gnueabi-ld
--with-as=/usr/bin/armv7a-hardfloat-linux-gnueabi-as --disable-libstdcxx-pch
--prefix=/repo/gcc-trunk//binary-trunk-r10-7327-20200323085706-g2fa4b1ffd6e-checking-yes-rtl-df-extra-pr94286-armv7a-hardfloat
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 10.0.1 20200323 (experimental) (GCC)