[Bug target/118170] New: ICE: in riscv_sched_variable_issue, at config/riscv/riscv.cc:9790 with -mcpu=tt-ascalon-d8 and _Float16

[zsojka at seznam dot cz via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118170

            Bug ID: 118170
           Summary: ICE: in riscv_sched_variable_issue, at
                    config/riscv/riscv.cc:9790 with -mcpu=tt-ascalon-d8
                    and _Float16
           Product: gcc
           Version: 15.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zsojka at seznam dot cz
  Target Milestone: ---
              Host: x86_64-pc-linux-gnu
            Target: riscv64-unknown-linux-gnu

Created attachment 59946
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=59946&action=edit
reduced testcase

Compiler output:
$ riscv64-unknown-linux-gnu-gcc -O2 -mcpu=tt-ascalon-d8 testcase.c 
during RTL pass: sched1
testcase.c: In function 'foo':
testcase.c:7:1: internal compiler error: in riscv_sched_variable_issue, at
config/riscv/riscv.cc:9790
    7 | }
      | ^
0x35e74e1 internal_error(char const*, ...)
        /repo/gcc-trunk/gcc/diagnostic-global-context.cc:517
0x10b7c37 fancy_abort(char const*, int, char const*)
        /repo/gcc-trunk/gcc/diagnostic.cc:1722
0xc27518 riscv_sched_variable_issue
        /repo/gcc-trunk/gcc/config/riscv/riscv.cc:9790
0xc27518 riscv_sched_variable_issue
        /repo/gcc-trunk/gcc/config/riscv/riscv.cc:9770
0x311cadd schedule_block(basic_block_def**, void*)
        /repo/gcc-trunk/gcc/haifa-sched.cc:6928
0x17ffe2a schedule_region
        /repo/gcc-trunk/gcc/sched-rgn.cc:3213
0x17ffe2a schedule_insns()
        /repo/gcc-trunk/gcc/sched-rgn.cc:3535
0x180026c schedule_insns()
        /repo/gcc-trunk/gcc/sched-rgn.cc:3521
0x180026c rest_of_handle_sched
        /repo/gcc-trunk/gcc/sched-rgn.cc:3739
0x180026c execute
        /repo/gcc-trunk/gcc/sched-rgn.cc:3849
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.


$ riscv64-unknown-linux-gnu-gcc -v
Using built-in specs.
COLLECT_GCC=/repo/gcc-trunk/binary-latest-riscv64/bin/riscv64-unknown-linux-gnu-gcc
COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-20241221071321-r15-6405-g0b63840e07132f-checking-yes-rtl-df-extra-riscv64/bin/../libexec/gcc/riscv64-unknown-linux-gnu/15.0.0/lto-wrapper
Target: riscv64-unknown-linux-gnu
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-isa-spec=2.2
--with-sysroot=/usr/riscv64-unknown-linux-gnu --build=x86_64-pc-linux-gnu
--host=x86_64-pc-linux-gnu --target=riscv64-unknown-linux-gnu
--with-ld=/usr/bin/riscv64-unknown-linux-gnu-ld
--with-as=/usr/bin/riscv64-unknown-linux-gnu-as --disable-multilib
--enable-libsanitizer --disable-libstdcxx-pch
--prefix=/repo/gcc-trunk//binary-trunk-20241221071321-r15-6405-g0b63840e07132f-checking-yes-rtl-df-extra-riscv64
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 15.0.0 20241221 (experimental) (GCC)