common.opt (freschedule-modulo-scheduled-loops): New flag.

2004-08-08  Mostafa Hagog  <mustafa@il.ibm.com>
	Ayal Zaks <zaks@il.ibm.com>

	* common.opt (freschedule-modulo-scheduled-loops): New flag.
	* final.c (final_scan_insn): Handle NOTE_DISABLE_SCHED_OF_BLOCK.
	* modulo-sched.c (sms_schedule): Emit a note to disable scheduling
	when -freschedule-modulo-scheduled-loops flag is not specified.
	(sms_schedule_by_order, ps_insn_advance_column, add_node_to_ps,
	add_node_to_ps, ps_has_conflicts, ps_add_node_check_conflicts):
	More accurate placing of insn in row of partial schedule.
	(ps_insn_find_column): New function.
	* rtl.h (NOTE_DISABLE_SCHED_OF_BLOCK): New note.
	* sched-rgn.c (sched_is_disabled_for_current_region_p): New.
	(schedule_region): Use sched_is_disabled_for_current_region_p.
	* docs/invoke.texi: Document -freschedule-modulo-scheduled-loops.

Co-Authored-By: Ayal Zaks <zaks@il.ibm.com>

From-SVN: r85696

gcc/ChangeLog

+2004-08-08  Mostafa Hagog  <mustafa@il.ibm.com>
+	Ayal Zaks <zaks@il.ibm.com>
+
+	* common.opt (freschedule-modulo-scheduled-loops): New flag.
+	* final.c (final_scan_insn): Handle NOTE_DISABLE_SCHED_OF_BLOCK.
+	* modulo-sched.c (sms_schedule): Emit a note to disable scheduling
+	when -freschedule-modulo-scheduled-loops flag is not specified.
+	(sms_schedule_by_order, ps_insn_advance_column, add_node_to_ps,
+	add_node_to_ps, ps_has_conflicts, ps_add_node_check_conflicts):
+	More accurate placing of insn in row of partial schedule.
+	(ps_insn_find_column): New function.
+	* rtl.h (NOTE_DISABLE_SCHED_OF_BLOCK): New note.
+	* sched-rgn.c (sched_is_disabled_for_current_region_p): New.
+	(schedule_region): Use sched_is_disabled_for_current_region_p.
+	* docs/invoke.texi: Document -freschedule-modulo-scheduled-loops.
+
 2004-08-07  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* config/i386/i386.c (ix86_expand_clrmem): Revert the last

gcc/common.opt

@@ -543,6 +543,10 @@ fnew-ra
 Common Report Var(flag_new_regalloc)
 Use graph-coloring register allocation
 
+freschedule-modulo-scheduled-loops
+Common Report Var(flag_resched_modulo_sched)
+Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
+
 fnon-call-exceptions
 Common Report Var(flag_non_call_exceptions)
 Support synchronous non-call exceptions

gcc/doc/invoke.texi

@@ -308,8 +308,8 @@ in the following sections.
 -fsched-spec-load-dangerous  @gol
 -fsched-stalled-insns=@var{n} -sched-stalled-insns-dep=@var{n} @gol
 -fsched2-use-superblocks @gol
--fsched2-use-traces  -fsignaling-nans @gol
--fsingle-precision-constant  @gol
+-fsched2-use-traces -freschedule-modulo-scheduled-loops @gol
+-fsignaling-nans -fsingle-precision-constant  @gol
 -fstrength-reduce  -fstrict-aliasing  -ftracer  -fthread-jumps @gol
 -funroll-all-loops  -funroll-loops  -fpeel-loops @gol
 -funswitch-loops  -fold-unroll-loops  -fold-unroll-all-loops @gol
@@ -4393,6 +4393,12 @@ reality and hurt the performance.  This only makes
 sense when scheduling after register allocation, i.e.@: with
 @option{-fschedule-insns2} or at @option{-O2} or higher.
 
+@item -freschedule-modulo-scheduled-loops
+@opindex fscheduling-in-modulo-scheduled-loops
+The modulo scheduling comes before the traditional scheduling, if a loop was modulo scheduled
+we may want to prevent the later scheduling passes from changing its schedule, we use this
+option to control that.
+
 @item -fcaller-saves
 @opindex fcaller-saves
 Enable values to be allocated in registers that will be clobbered by

gcc/final.c

@@ -1704,6 +1704,7 @@ final_scan_insn (rtx insn, FILE *file, int optimize ATTRIBUTE_UNUSED,
 	case NOTE_INSN_FUNCTION_END:
 	case NOTE_INSN_REPEATED_LINE_NUMBER:
 	case NOTE_INSN_EXPECTED_VALUE:
+	case NOTE_DISABLE_SCHED_OF_BLOCK:
 	  break;
 
 	case NOTE_INSN_UNLIKELY_EXECUTED_CODE:

gcc/rtl.h

@@ -983,6 +983,12 @@ enum insn_note
   /* Generated at the start of a duplicated exit test.  */
   NOTE_INSN_LOOP_VTOP,
 
+  /* Mark that a block shouldn't be scheduled.  This is currently
+     used in modulo scheduling. Modulo scheduling  adds this note
+     to the blocks of the modulo-scheduled loops to disable scheduling
+     them in the later traditional scheduling passes.  */
+  NOTE_DISABLE_SCHED_OF_BLOCK,
+
   /* This kind of note is generated at the end of the function body,
      just before the return insn or return label.  In an optimizing
      compilation it is deleted by the first jump optimization, after

gcc/sched-rgn.c

@@ -117,6 +117,7 @@ static int *out_edges;
 static int is_cfg_nonregular (void);
 static int build_control_flow (struct edge_list *);
 static void new_edge (int, int);
+static bool sched_is_disabled_for_current_region_p (void);
 
 /* A region is the main entity for interblock scheduling: insns
    are allowed to move between blocks in the same region, along
@@ -2332,6 +2333,37 @@ debug_dependencies (void)
   fprintf (sched_dump, "\n");
 }
 
+/* Returns true if all the basic blocks of the current region have
+   NOTE_DISABLE_SCHED_OF_BLOCK which means not to schedule that region.  */
+static bool
+sched_is_disabled_for_current_region_p (void)
+{
+  rtx first_bb_insn, last_bb_insn, insn;
+  int bb;
+
+  for (bb = 0; bb < current_nr_blocks; bb++)
+    {
+      bool disable_sched = false;
+      /* Searching for NOTE_DISABLE_SCHED_OF_BLOCK note between the
+         start and end of the basic block. */
+      get_block_head_tail (BB_TO_BLOCK (bb), &first_bb_insn,
+			   &last_bb_insn);
+      for (insn = last_bb_insn; insn != NULL && insn != first_bb_insn;
+           insn = PREV_INSN (insn))
+      	if (GET_CODE (insn) == NOTE
+	    && (NOTE_LINE_NUMBER (insn)
+	        == NOTE_DISABLE_SCHED_OF_BLOCK))
+          {
+              disable_sched = true;
+	      break;
+          }
+      if (! disable_sched)
+	return false;
+    }
+
+  return true;
+}
+
 /* Schedule a region.  A region is either an inner loop, a loop-free
    subroutine, or a single basic block.  Each bb in the region is
    scheduled after its flow predecessors.  */
@@ -2347,6 +2379,11 @@ schedule_region (int rgn)
   current_nr_blocks = RGN_NR_BLOCKS (rgn);
   current_blocks = RGN_BLOCKS (rgn);
 
+  /* Don't schedule region that is marked by
+     NOTE_DISABLE_SCHED_OF_BLOCK.  */
+  if (sched_is_disabled_for_current_region_p ())
+    return;
+
   init_deps_global ();
 
   /* Initializations for region data dependence analysis.  */