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[Bug middle-end/46837] induct compiled with -ffast-math -fschedule-insns -fsched-pressure -O3 ~30% slower


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46837

Steven Bosscher <steven at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2010.12.08 00:35:39
                 CC|                            |steven at gcc dot gnu.org
     Ever Confirmed|0                           |1

--- Comment #4 from Steven Bosscher <steven at gcc dot gnu.org> 2010-12-08 00:35:39 UTC ---
Re. comment #2: For the i386 backends -fschedule-insns is disabled even at -O2
and -O3. See gcc/config/i386/i386.c:ix86_option_optimization_table:

static const struct default_options ix86_option_optimization_table[] =
  {
    /* Turn off -fschedule-insns by default.  It tends to make the
       problem with not enough registers even worse.  */
#ifdef INSN_SCHEDULING
    { OPT_LEVELS_ALL, OPT_fschedule_insns, NULL, 0 },
#endif


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