[Bug target/112903] New: ICE: in df_scan_verify, at df-scan.cc:4239 with -O -fdump-rtl-pro_and_epilogue

[Bug target/112903] New: ICE: in df_scan_verify, at df-scan.cc:4239 with -O -fdump-rtl-pro_and_epilogue

[iamanonymous.cs at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112903

            Bug ID: 112903
           Summary: ICE: in df_scan_verify, at df-scan.cc:4239 with -O
                    -fdump-rtl-pro_and_epilogue
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: iamanonymous.cs at gmail dot com
  Target Milestone: ---

*******************************************************************************
OS and Platform:
$ uname -a:
Linux ubuntu 4.15.0-213-generic #224-Ubuntu SMP Mon Jun 19 13:30:12 UTC 2023
x86_64 x86_64 x86_64 GNU/Linux
*******************************************************************************
gcc version:
$ gcc -v
Using built-in specs.
COLLECT_GCC=/root/gcc_set/202311291030/bin/gcc
COLLECT_LTO_WRAPPER=/root/gcc_set/202311291030/libexec/gcc/x86_64-pc-linux-gnu/14.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc/configure --prefix=/root/gcc_set/202311291030
--with-gmp=/root/build_essential --with-mpfr=/root/build_essential
--with-mpc=/root/build_essential --enable-languages=c,c++ --disable-multilib
--with-sanitizer=address,undefined,thread,leak
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 14.0.0 20231129 (experimental) (GCC) 

git version: 99fa0bfd63d97825c4221dcd3123940f1d0e6291
*******************************************************************************
Program:
$ cat mutant.c
int __RTL (startwith ("pro_and_epilogue")) a ()
{
(function ""
  (insn-chain
    (block 2
      (edge-from b )
      (cnote 6 [bb 2] NOTE_INSN_BASIC_BLOCK)
      (cjump_insn 0 (set (pc)
                    (if_then_else (ge (reg flags)
                            (const_int 0))
                        (label_ref 16)
                        (pc))) )
    ) (block 3
      (cnote 1 [bb 3] NOTE_INSN_BASIC_BLOCK)
      (cjump_insn 9 (set (pc)
                    (label_ref 20)) )
    ) (block 4
      (edge-from 2)
      (clabel 16 2)
      (cnote 7 [bb 4] NOTE_INSN_BASIC_BLOCK)
    ) (block 5
      (edge-from 4 (flags "FALLTHRU"))
      (edge-from 3)
      (clabel 20 3)
      (cnote 21 [bb 5] NOTE_INSN_BASIC_BLOCK)
      (edge-to exit (flags "FALLTHRU"))
    ) ) )  
}

*******************************************************************************
Command Lines:
$ gcc -O -fdump-rtl-pro_and_epilogue mutant.c
during RTL pass: dse2
mutant.c: In function ‘a’:
mutant.c:28:1: internal compiler error: in df_scan_verify, at df-scan.cc:4239
   28 | }
      | ^
0x76308c df_scan_verify()
        ../../gcc/gcc/df-scan.cc:4239
0xb3d8f4 df_verify()
        ../../gcc/gcc/df-core.cc:1834
0xb3d8f4 df_analyze_1
        ../../gcc/gcc/df-core.cc:1221
0x1dfbc79 rest_of_handle_dse
        ../../gcc/gcc/dse.cc:3711
0x1dfbc79 execute
        ../../gcc/gcc/dse.cc:3787
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.


Also ICE on trunk, compiler explorer: https://godbolt.org/z/ooM769Yvd

[Bug target/112903] ICE: in df_scan_verify, at df-scan.cc:4239 with -O -fdump-rtl-pro_and_epilogue

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112903

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dmalcolm at gcc dot gnu.org,
                   |                            |rguenth at gcc dot gnu.org
             Target|                            |x86_64-*-*

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Uh, not sure if we want RTL FE fuzzing.  startwith ("pro_and_epilogue")
or similar is probably not expected to work without spending work on it.