[Bug tree-optimization/108367] New: [12/13 Regression] ICE: verify_ssa failed (error: definition in block 4 does not dominate use in block 3)

[Bug tree-optimization/108367] New: [12/13 Regression] ICE: verify_ssa failed (error: definition in block 4 does not dominate use in block 3)

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108367

            Bug ID: 108367
           Summary: [12/13 Regression] ICE: verify_ssa failed (error:
                    definition in block 4 does not dominate use in block
                    3)
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code, openacc
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---

gcc 13.0.0 20230108 snapshot (g:e3a4bd0bbdccdde0cff85f93064b01a44fb10d2a) ICEs
when compiling libgomp/testsuite/libgomp.oacc-c-c++-common/pr89376.c w/ -Os
-fopenacc -fno-tree-fre -fno-tree-vrp -g:

% gcc-13 -Os -fopenacc -fno-tree-fre -fno-tree-vrp -g -c
libgomp/testsuite/libgomp.oacc-c-c++-common/pr89376.c
libgomp/testsuite/libgomp.oacc-c-c++-common/pr89376.c: In function
'main._omp_fn.0':
libgomp/testsuite/libgomp.oacc-c-c++-common/pr89376.c:14:1: error: definition
in block 4 does not dominate use in block 3
   14 | }
      | ^
for SSA_NAME: rw_7 in statement:
# DEBUG rw => rw_7
during GIMPLE pass: parloops
libgomp/testsuite/libgomp.oacc-c-c++-common/pr89376.c:14:1: internal compiler
error: verify_ssa failed
0x1149446 verify_ssa(bool, bool)
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20230108/work/gcc-13-20230108/gcc/tree-ssa.cc:1211
0xdfea25 execute_function_todo
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20230108/work/gcc-13-20230108/gcc/passes.cc:2098
0xdfee5e execute_todo
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20230108/work/gcc-13-20230108/gcc/passes.cc:2145

[Bug tree-optimization/108367] [12/13 Regression] ICE: verify_ssa failed (error: definition in block 4 does not dominate use in block 3) since r12-5138-ge82c382971664d6f

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108367

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2023-01-11
            Summary|[12/13 Regression] ICE:     |[12/13 Regression] ICE:
                   |verify_ssa failed (error:   |verify_ssa failed (error:
                   |definition in block 4 does  |definition in block 4 does
                   |not dominate use in block   |not dominate use in block
                   |3)                          |3) since
                   |                            |r12-5138-ge82c382971664d6f
   Target Milestone|---                         |12.3
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
                 CC|                            |aldyh at gcc dot gnu.org,
                   |                            |marxin at gcc dot gnu.org

--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
Started with r12-5138-ge82c382971664d6f.

[Bug tree-optimization/108367] [12/13 Regression] ICE: verify_ssa failed (error: definition in block 4 does not dominate use in block 3) since r12-5138-ge82c382971664d6f

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108367

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
The OACC parloops pass adds a loop-around edge which short-cuts the definition
of the debug use.  I don't see anywhere how that handles debug stmts - maybe it
gets fixed during lowering ... (yes, with -fno-checking it looks OK after
ompexpssa1).

The offending rev. is most certainly not the cause of the actual issue.

[Bug tree-optimization/108367] [12/13 Regression] ICE: verify_ssa failed (error: definition in block 4 does not dominate use in block 3) since r12-5138-ge82c382971664d6f

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108367

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2

[Bug tree-optimization/108367] [12/13/14 Regression] ICE: verify_ssa failed (error: definition in block 4 does not dominate use in block 3) since r12-5138-ge82c382971664d6f

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108367

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|12.3                        |12.4

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 12.3 is being released, retargeting bugs to GCC 12.4.