[Bug target/48808] ICE in spill_failure, at reload1.c:2113

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

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48808

Ian Bolton <ibolton at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |ice-on-valid-code
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2011.05.03 10:54:06
                 CC|                            |ibolton at gcc dot gnu.org
     Ever Confirmed|0                           |1
      Known to fail|                            |4.7.0

--- Comment #1 from Ian Bolton <ibolton at gcc dot gnu.org> 2011-05-03 10:54:06 UTC ---
Confirmed on r173122 of trunk, using the command-line args provided by the
reporter.

I have managed to traced it back to happening somewhere between r172185 (works)
and r172316 (ICEs) of trunk.  Looking through the Changelogs for "reload", the
most likely candidates are:

r172297 | cltang | 2011-04-12 05:42:55 +0100 (Tue, 12 Apr 2011) | 10 lines

2011-04-11  Chung-Lin Tang  <cltang@codesourcery.com>
            Richard Earnshaw  <rearnsha@arm.com>

        PR target/48250
        * config/arm/arm.c (arm_legitimize_reload_address): Update cases
        to use sign-magnitude offsets. Reject unsupported unaligned
        cases. Add detailed description in comments.
        * config/arm/arm.md (reload_outdf): Disable for ARM mode; change
        condition from TARGET_32BIT to TARGET_ARM.

r172231 | aesok | 2011-04-09 20:10:45 +0100 (Sat, 09 Apr 2011) | 8 lines

        * expr.c (expand_expr_real_1): Use add_to_hard_reg_set function
        instead of loop.
        * sel-sched.c (mark_unavailable_hard_regs): Likewise.
        * function.c (record_hard_reg_sets): Likewise.
        * ira.c (compute_regs_asm_clobbered): Likewise.
        * sched-deps.c (sched_analyze_1): Likewise.
        * reload1.c (mark_reload_reg_in_use, choose_reload_regs): Likewise.

r172197 | danglin | 2011-04-08 17:21:39 +0100 (Fri, 08 Apr 2011) | 12 lines

        PR target/48366
        * config/pa/pa.c (hppa_register_move_cost): Increase to 18 cost of
        move from floating point to shift amount register .
        (emit_move_sequence): Remove secondary reload support for floating
        point to shift amount amount register copies.
        (pa_secondary_reload): Return GENERAL_REGS for floating point/shift
        amount register copies.
        * config/pa/pa32-regs.h (HARD_REGNO_MODE_OK): For shift amount
        register, return false if mode isn't a scalar integer mode.
        * config/pa/pa64-regs.h (HARD_REGNO_MODE_OK): Likewise.

I don't have more time to devote to investigating this today, but hopefully
someone else will be able to work out which change it was.