[Bug middle-end/107236] New: [OpenMP] ICE for reverse offload: in expand_GOMP_TARGET_REV, at internal-fn.cc:376

[Bug middle-end/107236] New: [OpenMP] ICE for reverse offload: in expand_GOMP_TARGET_REV, at internal-fn.cc:376

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107236

            Bug ID: 107236
           Summary: [OpenMP] ICE for reverse offload: in
                    expand_GOMP_TARGET_REV, at internal-fn.cc:376
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code, openmp
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: burnus at gcc dot gnu.org
  Target Milestone: ---

Created attachment 53696
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=53696&action=edit
Testcase - compile as: gfortran -fopenmp test.f90

This only shows up if ENABLE_OFFLOADING is true during the GCC build.

The attached testcase fails with:

rev-test-ice.f90:5:33: internal compiler error: in expand_GOMP_TARGET_REV, at
internal-fn.cc:376
    5 |   !$omp target device(ancestor:1)
      |                                 ^
0x791309 expand_GOMP_TARGET_REV
       
/net/build1-fossa-cs/scratch/tburnus/fsf.mainline.x86_64-linux-gnu-amdgcn/src/gcc-mainline/gcc/internal-fn.cc:376
0xb2c147 expand_call_stmt

[Bug middle-end/107236] [OpenMP] ICE for reverse offload: in expand_GOMP_TARGET_REV, at internal-fn.cc:376

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107236

--- Comment #1 from Tobias Burnus <burnus at gcc dot gnu.org> ---
The problem seems to be that:

execute_omp_device_lower ()
...
        tree lhs = gimple_call_lhs (stmt), rhs = NULL_TREE;
        tree type = lhs ? TREE_TYPE (lhs) : integer_type_node;
        switch (gimple_call_internal_fn (stmt))
          {
          case IFN_GOMP_TARGET_REV:
is never reached.

Thus, IFN_GOMP_TARGET_REV remains - and the assert that IFN_GOMP_TARGET_REV has
been removed fails, leading to the ICE.

It seems as if pass_omp_device_lower::gate(...) wrongly skips the generated
nested
function for parallel. The current check is:

      return (!(fun->curr_properties & PROP_gimple_lomp_dev)
              || (flag_openmp
                  && cgraph_node::get (fun->decl)->calls_declare_variant_alt));

[Bug middle-end/107236] [OpenMP] ICE for reverse offload: in expand_GOMP_TARGET_REV, at internal-fn.cc:376

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107236

--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Tobias Burnus <burnus@gcc.gnu.org>:

https://gcc.gnu.org/g:178ac530fe67e4f2fc439cc4ce89bc19d571ca31

commit r13-3455-g178ac530fe67e4f2fc439cc4ce89bc19d571ca31
Author: Tobias Burnus <tobias@codesourcery.com>
Date:   Mon Oct 24 15:19:00 2022 +0200

    OpenMP: Fix reverse offload GOMP_TARGET_REV IFN corner cases [PR107236]

    For 'target parallel' and similarly nested directives, cgraph_node's
    calls_declare_variant_alt was not set in the parent region node but in
    cfun->decl. Hence, pass_omp_device_lower did not process handle the
    internal function GOMP_TARGET_REV. - Solution is to set it to the
    DECL_CONTEXT, which is set in adjust_context_and_scope.

    The cgraph_node::create_clone issue is exposed with -O2 for the existing
    libgomp.fortran/reverse-offload-1.f90.

            PR middle-end/107236

    gcc/ChangeLog:
            * omp-expand.cc (expand_omp_target): Set calls_declare_variant_alt
            in DECL_CONTEXT and not to cfun->decl.
            * cgraphclones.cc (cgraph_node::create_clone): Copy also the
            node's calls_declare_variant_alt value.

    gcc/testsuite/ChangeLog:
            * gfortran.dg/gomp/target-device-ancestor-6.f90: New test.

[Bug middle-end/107236] [OpenMP] ICE for reverse offload: in expand_GOMP_TARGET_REV, at internal-fn.cc:376

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107236

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |FIXED

--- Comment #3 from Tobias Burnus <burnus at gcc dot gnu.org> ---
FIXED on GCC 13/mainline.