[Bug tree-optimization/79472] [8 Regression] x86-64: Switch table generation fails if default case has different code

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79472

--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Author: jakub
Date: Wed May  3 07:49:43 2017
New Revision: 247538

URL: https://gcc.gnu.org/viewcvs?rev=247538&root=gcc&view=rev
Log:
        PR tree-optimization/79472
        * tree-switch-conversion.c (struct switch_conv_info): Add
        contiguous_range and default_case_nonstandard fields.
        (collect_switch_conv_info): Compute contiguous_range and
        default_case_nonstandard fields, don't clear final_bb if
        contiguous_range and only the default case doesn't have the required
        structure.
        (check_all_empty_except_final): Set default_case_nonstandard instead
        of failing if contiguous_range and the default case doesn't have empty
        block.
        (check_final_bb): Add SWTCH argument, don't fail if contiguous_range
        and only the default case doesn't have the required constants.  Skip
        virtual phis.
        (gather_default_values): Skip virtual phis.  Allow non-NULL CASE_LOW
        if default_case_nonstandard.
        (build_constructors): Build constant 1 just once.  Assert that default
        values aren't inserted in between cases if contiguous_range.  Skip
        virtual phis.
        (build_arrays): Skip virtual phis.
        (prune_bbs): Add DEFAULT_BB argument, don't remove that bb.
        (fix_phi_nodes): Don't add e2f phi arg if default_case_nonstandard.
        Handle virtual phis.
        (gen_inbound_check): Handle default_case_nonstandard case.
        (process_switch): Adjust check_final_bb caller.  Call
        gather_default_values with the first non-default case instead of
        default case if default_case_nonstandard.

        * gcc.dg/tree-ssa/vrp40.c: Add -fno-tree-switch-conversion to
dg-options.
        * gcc.dg/tree-ssa/vrp113.c: New test.
        * gcc.dg/tree-ssa/cswtch-3.c: New test.
        * gcc.dg/tree-ssa/cswtch-4.c: New test.
        * gcc.dg/tree-ssa/cswtch-5.c: New test.

Added:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/cswtch-3.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/cswtch-4.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/cswtch-5.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/vrp113.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.dg/tree-ssa/vrp40.c
    trunk/gcc/tree-switch-conversion.c