[Bug target/110800] New: [gcn] ICE (segfault) 'during RTL pass: jump' in delete_trivially_dead_insns -> count_reg_usage

[Bug target/110800] New: [gcn] ICE (segfault) 'during RTL pass: jump' in delete_trivially_dead_insns -> count_reg_usage

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110800

            Bug ID: 110800
           Summary: [gcn] ICE (segfault) 'during RTL pass: jump' in
                    delete_trivially_dead_insns -> count_reg_usage
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: burnus at gcc dot gnu.org
                CC: grahams at gcc dot gnu.org
  Target Milestone: ---
            Target: amdgcn-amdhsa

Testcase is test_target_PureVirDestr.cpp at
https://github.com/SOLLVE/sollve_vv/pull/751

Simply go to any sollve_vv directory, run "wget" on
https://raw.githubusercontent.com/SOLLVE/sollve_vv/a3be96d534124e744acc979e2e33b402a1b330cd/tests/5.2/unified_shared_mem/test_target_PureVirDestr.cpp


And then compile, e.g. as follows. (Tested with mainline; comments in the pull
request indicate that OG13 fails identically.)

g++ -foffload-options=-march=gfx90a -fopenmp -I ompvv/ -DVERBOSE_MODE=1
test_target_PureVirDestr.cpp



The segfault happens for:

#0  0x00000000019175cc in count_reg_usage (x=<optimized out>, counts=0x2e618e0,
dest=<optimized out>, incr=1) at gcc/rtl.h:1934
1934      return REG_CHECK (x)->regno;

which is called (same function) as

1511      return XEXP (insn, 3);

which is called in

#2  0x000000000191c86b in delete_trivially_dead_insns (insns=<optimized out>,
nreg=514)    at gcc/cse.cc:7012
7012              count_reg_usage (insn, counts, NULL_RTX, 1);
(gdb) p debug_rtx(insn)
(insn 132 133 119 7 (set (reg:DI 508)
        (reg:DI -1)) "test_target_PureVirDestr.cpp":57:5 8 {*movdi_insn}
     (nil))



The ICE is:

during RTL pass: jump
test_target_PureVirDestr.cpp: In member function '__ct_base ':
test_target_PureVirDestr.cpp:57:5: internal compiler error: Segmentation fault
   57 |     }
      |     ^
0x101ad9f crash_signal  gcc/toplev.cc:314
0x7f463959408f ???  sysv/linux/x86_64/sigaction.c:0
0x19175cc count_reg_usage  gcc/cse.cc:6748
0x19173ea count_reg_usage  gcc/cse.cc:6788
0x191c86a delete_trivially_dead_insns(rtx_insn*, int)
        gcc/cse.cc:7012
0x18dc5c6 execute  gcc/cfgcleanup.cc:3237
...
gcn mkoffload: fatal error:
../../install/bin/x86_64-none-linux-gnu-accel-amdgcn-amdhsa-gcc returned 1 exit
status
compilation terminated.
lto-wrapper: fatal error:
.../install/libexec/gcc/x86_64-none-linux-gnu/14.0.0//accel/amdgcn-amdhsa/mkoffload
returned 1 exit status

[Bug target/110800] [gcn] ICE (segfault) 'during RTL pass: jump' in delete_trivially_dead_insns -> count_reg_usage when C++ exceptions are enabled + used

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110800

Tobias Burnus <burnus at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[gcn] ICE (segfault)        |[gcn] ICE (segfault)
                   |'during RTL pass: jump' in  |'during RTL pass: jump' in
                   |delete_trivially_dead_insns |delete_trivially_dead_insns
                   |-> count_reg_usage          |-> count_reg_usage when C++
                   |                            |exceptions are enabled +
                   |                            |used

--- Comment #1 from Tobias Burnus <burnus at gcc dot gnu.org> ---
The ICE is turned into plenty of linker errors (such as 'undefined symbol:
operator delete[](void*)') when compiling with:

   -fno-exceptions

It seems as if something goes wrong when exceptions are encountered. Still, an
ICE is wrong.

For the sister testcase, test_target_struct_obj_access.cpp (same pull request),
it fails with tons of:
  cc45cyOP.mkoffload.2.s:2601:1: error: symbol '.LEHE1' is already defined

That's actually how I found the -fno-exception as LEHE is added in
  gcc/except.cc:      ASM_GENERATE_INTERNAL_LABEL (reg_start_lab, "LEHB",
call_site_base + i);
  gcc/final.cc:     ASM_OUTPUT_DEBUG_LABEL (asm_out_file, "LEHB",