[Bug hsa/70857] [6/7 Regression] ICE with -fopenmp -fopenacc in insert_vi_for_tree, at tree-ssa-structalias.c:2813

["tschwinge at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70857

Thomas Schwinge <tschwinge at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |openacc
                 CC|                            |tschwinge at gcc dot gnu.org,
                   |                            |vries at gcc dot gnu.org

--- Comment #3 from Thomas Schwinge <tschwinge at gcc dot gnu.org> ---
I had a cursory look at this.  The ICE with
gcc/testsuite/gfortran.dg/gomp/gridify-1.f90 occurs for "-fopenacc -fopenmp
-O1", and disappears for "-fno-openacc", or alternatively to that, also
disappears if "hsa" offloading is disabled using the "-foffload" option. 
Backtrace:

    #1  0x0000000000da4d7c in insert_vi_for_tree (t=0x7ffff68d7258,
vi=vi@entry=0x20b8d40) at [...]/source-gcc/gcc/tree-ssa-structalias.c:2821
    #2  0x0000000000da9edb in create_function_info_for (decl=0x7ffff6a8ed20,
name=0x7ffff6a946c0 "vector_square_._omp_fn.0", 
        add_id=add_id@entry=false, nonlocal_p=nonlocal_p@entry=false) at
[...]/source-gcc/gcc/tree-ssa-structalias.c:5686
    #3  0x0000000000daf7c9 in ipa_pta_execute () at
[...]/source-gcc/gcc/tree-ssa-structalias.c:7703
    #4  0x0000000000db0a62 in (anonymous namespace)::pass_ipa_pta::execute
(this=0x1fa35e0) at [...]/source-gcc/gcc/tree-ssa-structalias.c:8041
    #5  0x0000000000afdd3d in execute_one_pass (pass=pass@entry=0x1fa35e0) at
[...]/source-gcc/gcc/passes.c:2344
    #6  0x0000000000afeac2 in execute_ipa_pass_list (pass=0x1fa35e0) at
[...]/source-gcc/gcc/passes.c:2774
    #7  0x0000000000afeaee in execute_ipa_pass_list (pass=0x1fa3580) at
[...]/source-gcc/gcc/passes.c:2786
    #8  0x00000000007e3805 in ipa_passes () at
[...]/source-gcc/gcc/cgraphunit.c:2266
    #9  symbol_table::compile (this=this@entry=0x7ffff68d10a8) at
[...]/source-gcc/gcc/cgraphunit.c:2405
    #10 0x00000000007e5b9a in symbol_table::finalize_compilation_unit
(this=0x7ffff68d10a8) at [...]/source-gcc/gcc/cgraphunit.c:2565
    #11 0x0000000000bc3a8a in compile_file () at
[...]/source-gcc/gcc/toplev.c:488
    #12 0x00000000005fd99d in do_compile () at
[...]/source-gcc/gcc/toplev.c:1987
    #13 toplev::main (this=this@entry=0x7fffffffcd60, argc=argc@entry=27,
argv=argv@entry=0x7fffffffce68) at [...]/source-gcc/gcc/toplev.c:2095
    #14 0x00000000005ff4d7 in main (argc=27, argv=0x7fffffffce68) at
[...]/source-gcc/gcc/main.c:39

This is the first pass_ipa_pta, run within pass_ipa_oacc, if "-fopenacc" is in
effect.  (That is required for OpenACC kernels processing; Tom CCed for your
information.)

    (gdb) break insert_vi_for_tree
    Breakpoint 4 at 0xd94660: file [...]/source-gcc/gcc/tree-ssa-structalias.c,
line 2817.
    (gdb) c
    Continuing.
    Breakpoint 4, insert_vi_for_tree (t=0x7ffff6aa50e0, vi=0x2091340)
    Breakpoint 4, insert_vi_for_tree (t=0x7ffff68d7258, vi=0x2091430)
    Breakpoint 4, insert_vi_for_tree (t=0x7ffff6a7f680, vi=0x2091480)
    Breakpoint 4, insert_vi_for_tree (t=0x7ffff6a8ee00, vi=0x20914d0)
    Breakpoint 4, insert_vi_for_tree (t=0x7ffff68d72d0, vi=0x20915c0)
    Breakpoint 4, insert_vi_for_tree (t=0x7ffff6a7f500, vi=0x2091610)
    Breakpoint 4, insert_vi_for_tree (t=0x7ffff6a8ed20, vi=0x2091660)
    Breakpoint 4, insert_vi_for_tree (t=0x7ffff68d7258, vi=0x2091750)

That is, unexpectedly, the same "t" that we've already seen in the second hit
of that breakpoint, and thus the second gcc_assert will trigger:

    /* Map from trees to variable infos.  */
    static hash_map<tree, varinfo_t> *vi_for_tree;
    [...]
    /* Insert ID as the variable id for tree T in the vi_for_tree map.  */

    static void
    insert_vi_for_tree (tree t, varinfo_t vi)
    {
      gcc_assert (vi);
      gcc_assert (!vi_for_tree->put (t, vi));
    }

    (gdb) call debug_tree(t)
     <result_decl 0x7ffff68d7258 D.3465
        type <void_type 0x7ffff68e6150 void VOID
            align 8 symtab 0 alias set -1 canonical type 0x7ffff68e6150
            pointer_to_this <pointer_type 0x7ffff68e62a0>>
        ignored VOID file
source-gcc/gcc/testsuite/gfortran.dg/gomp/gridify-1.f90 line 7 col 0
        align 8 context <function_decl 0x7ffff6a8ed20
vector_square_._omp_fn.0>>