[Bug rtl-optimization/94014] New: ICE: in model_update_limit_points_in_group, at haifa-sched.c:1988 with -fsched-pressure --param=sched-pressure-algorithm=2

[zsojka at seznam dot cz]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94014

            Bug ID: 94014
           Summary: ICE: in model_update_limit_points_in_group, at
                    haifa-sched.c:1988 with -fsched-pressure
                    --param=sched-pressure-algorithm=2
           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: riscv64-unknown-linux-gnu

Created attachment 47956
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=47956&action=edit
reduced testcase

This ICE triggers sometimes during testing, the compiler flags are quite
similar; this testcase is one of the smaller ones triggering this ICE.

Compiler output:
$ riscv64-unknown-linux-gnu-gcc -O2 -fno-if-conversion -fsched-pressure
-fno-split-wide-types --param=max-sched-extend-regions-iters=2
--param=sched-pressure-algorithm=2 testcase.c 
during RTL pass: sched1
testcase.c: In function 'foo':
testcase.c:9:1: internal compiler error: in model_update_limit_points_in_group,
at haifa-sched.c:1986
    9 | }
      | ^
0x85ed62 model_update_limit_points_in_group
        /repo/gcc-trunk/gcc/haifa-sched.c:1986
0x85ed62 model_update_limit_points
        /repo/gcc-trunk/gcc/haifa-sched.c:1997
0x85ed62 schedule_insn
        /repo/gcc-trunk/gcc/haifa-sched.c:4089
0x157807b schedule_block(basic_block_def**, void*)
        /repo/gcc-trunk/gcc/haifa-sched.c:6897
0xe547e7 schedule_region
        /repo/gcc-trunk/gcc/sched-rgn.c:3183
0xe547e7 schedule_insns()
        /repo/gcc-trunk/gcc/sched-rgn.c:3522
0xe54c33 schedule_insns()
        /repo/gcc-trunk/gcc/sched-rgn.c:3508
0xe54c33 rest_of_handle_sched
        /repo/gcc-trunk/gcc/sched-rgn.c:3726
0xe54c33 execute
        /repo/gcc-trunk/gcc/sched-rgn.c:3834
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.

$ 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-r10-6995-20200303110626-g9b4f00dd3f7-checking-yes-rtl-df-extra-riscv64/bin/../libexec/gcc/riscv64-unknown-linux-gnu/10.0.1/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-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
--disable-libstdcxx-pch
--prefix=/repo/gcc-trunk//binary-trunk-r10-6995-20200303110626-g9b4f00dd3f7-checking-yes-rtl-df-extra-riscv64
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 10.0.1 20200303 (experimental) (GCC)