PR opt/12617

[Jan Hubicka <jh at suse dot cz>]

Hi,
this patch reorders ifcvt and bbro so we don't end up with strange
artefacts.  Apparently no one remembers exactly why we did it other way
around, one possible explanation is that it allows more ifcvt to happen,
but Andreas kindly SPEC tested it and the results are positive.  I am
not sure I can send the results so just summary:


Size of binaries:
 164.gzip: Base: 62604 bytes
 164.gzip: Peak: 62604 bytes
 175.vpr: Base: 167322 bytes
 175.vpr: Peak: 167322 bytes
 176.gcc: Base: 1605961 bytes
 176.gcc: Peak: 1605193 bytes
 181.mcf: Base: 25525 bytes
 181.mcf: Peak: 25525 bytes
 186.crafty: Base: 224346 bytes
 186.crafty: Peak: 224346 bytes
 197.parser: Base: 143568 bytes
 197.parser: Peak: 143568 bytes
 252.eon: Base: 635177 bytes
 252.eon: Peak: 635177 bytes
 253.perlbmk: Base: 666949 bytes
 253.perlbmk: Peak: 666949 bytes
 254.gap: Base: 542358 bytes
 254.gap: Peak: 542358 bytes
 255.vortex: Base: 683474 bytes
 255.vortex: Peak: 683410 bytes
 256.bzip2: Base: 53888 bytes
 256.bzip2: Peak: 53888 bytes
 300.twolf: Base: 221391 bytes
 300.twolf: Peak: 221391 bytes
 =============================
 Total: Base: 5032563 bytes
 Total: Peak: 5031731 bytes

Compile time is 1% better and score is one spec point higher (down in
the noise)

	PR opt/12617
	* toplev.c (dump_file_index): Reorder ce3 and bbro.
	(dump_file): Likewise.
	(rest_of_compilation): Likewise.
Index: toplev.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/toplev.c,v
retrieving revision 1.855
diff -c -3 -p -r1.855 toplev.c
*** toplev.c	29 Dec 2003 09:25:45 -0000	1.855
--- toplev.c	29 Dec 2003 10:16:27 -0000
*************** enum dump_file_index
*** 277,284 ****
    DFI_flow2,
    DFI_peephole2,
    DFI_rnreg,
-   DFI_bbro,
    DFI_ce3,
    DFI_branch_target_load,
    DFI_sched2,
    DFI_stack,
--- 277,284 ----
    DFI_flow2,
    DFI_peephole2,
    DFI_rnreg,
    DFI_ce3,
+   DFI_bbro,
    DFI_branch_target_load,
    DFI_sched2,
    DFI_stack,
*************** static struct dump_file_info dump_file[D
*** 328,335 ****
    { "flow2",	'w', 1, 0, 0 },
    { "peephole2", 'z', 1, 0, 0 },
    { "rnreg",	'n', 1, 0, 0 },
-   { "bbro",	'B', 1, 0, 0 },
    { "ce3",	'E', 1, 0, 0 },
    { "btl",	'd', 1, 0, 0 }, /* Yes, duplicate enable switch.  */
    { "sched2",	'R', 1, 0, 0 },
    { "stack",	'k', 1, 0, 0 },
--- 328,335 ----
    { "flow2",	'w', 1, 0, 0 },
    { "peephole2", 'z', 1, 0, 0 },
    { "rnreg",	'n', 1, 0, 0 },
    { "ce3",	'E', 1, 0, 0 },
+   { "bbro",	'B', 1, 0, 0 },
    { "btl",	'd', 1, 0, 0 }, /* Yes, duplicate enable switch.  */
    { "sched2",	'R', 1, 0, 0 },
    { "stack",	'k', 1, 0, 0 },
*************** rest_of_compilation (tree decl)
*** 3460,3473 ****
      }
  #endif
  
-   if (optimize > 0)
-     {
-       if (flag_rename_registers || flag_cprop_registers)
- 	rest_of_handle_regrename (decl, insns);
- 
-       rest_of_handle_reorder_blocks (decl, insns);
-     }
- 
    if (flag_if_conversion2)
      {
        timevar_push (TV_IFCVT2);
--- 3460,3465 ----
*************** rest_of_compilation (tree decl)
*** 3479,3501 ****
        timevar_pop (TV_IFCVT2);
      }
  
!     if (flag_branch_target_load_optimize2)
!       {
! 	/* Leave this a warning for now so that it is possible to experiment
! 	   with running this pass twice.  In 3.6, we should either make this
! 	   an error, or use separate dump files.  */
! 	if (flag_branch_target_load_optimize)
! 	  warning ("branch target register load optimization is not intended "
! 		   "to be run twice");
  
! 	open_dump_file (DFI_branch_target_load, decl);
  
! 	branch_target_load_optimize (insns, true);
  
! 	close_dump_file (DFI_branch_target_load, print_rtl_with_bb, insns);
  
! 	ggc_collect ();
!       }
  
  #ifdef INSN_SCHEDULING
    if (optimize > 0 && flag_schedule_insns_after_reload)
--- 3471,3501 ----
        timevar_pop (TV_IFCVT2);
      }
  
!   if (optimize > 0)
!     {
!       if (flag_rename_registers || flag_cprop_registers)
! 	rest_of_handle_regrename (decl, insns);
  
!       rest_of_handle_reorder_blocks (decl, insns);
!     }
! 
!   if (flag_branch_target_load_optimize2)
!     {
!       /* Leave this a warning for now so that it is possible to experiment
! 	 with running this pass twice.  In 3.6, we should either make this
! 	 an error, or use separate dump files.  */
!       if (flag_branch_target_load_optimize)
! 	warning ("branch target register load optimization is not intended "
! 		 "to be run twice");
  
!       open_dump_file (DFI_branch_target_load, decl);
  
!       branch_target_load_optimize (insns, true);
  
!       close_dump_file (DFI_branch_target_load, print_rtl_with_bb, insns);
! 
!       ggc_collect ();
!     }
  
  #ifdef INSN_SCHEDULING
    if (optimize > 0 && flag_schedule_insns_after_reload)