haifa-sched.c: Include "hashtab.h"

	* haifa-sched.c: Include "hashtab.h"
	(sched_no_dce): New global variable.
	(INSN_EXACT_TICK, INSN_TICK_ESTIMATE, FEEDS_BACKTRACK_INSN,
	SHADOW_P): New macros.
	(last_clock_var, cycle_issued_insns): Move declarations.
	(must_backtrack): New static variable.
	(struct delay_pair): New structure.
	(delay_htab, delay_htab_i2): New static variables.
	(delay_hash_i1, delay_hash_i2, delay_i1_eq, delay_i2_eq,
	record_delay_slot_pair, pair_delay, add_delay_dependencies): New
	functions.
	(dep_cost_1): If delay pairs exist, try to look up the insns and
	use the correct pair delay if we find them.
	(rank-for_schedule): Tweak priority for insns that must be scheduled
	soon to avoid backtracking.
	(queue_insn): Detect conditions which force backtracking.
	(ready_add): Likewise.
	(struct sched_block_state): Add member shadows_only_p.
	(struct haifa_save_data): New structure.
	(backtrack_queue): New static variable.
	(mark_backtrack_feeds, copy_insn_list, save_backtrack_point,
	unschedule_insns_until, restore_last_backtrack_point,
	free_topmost_backtrack_point, free_backtrack_queue,
	estimate_insn_tick, estimate_shadow_tick): New functions.
	(prune_ready_list): New arg shadows_only_p.  All callers changed.
	If true, remove everything that isn't SHADOW_P.  Look up delay
	pairs and estimate ticks to avoid scheduling the first insn too
	early.
	(verify_shadows): New function.
	(schedule_block): Add machinery to enable backtracking.
	(sched_init): Take sched_no_dce into account when setting
	DF_LR_RUN_DCE.
	(free_delay_pairs): New function.
	(init_h_i_d): Initialize INSN_EXACT_TICK.
	* Makefile.in (haifa-sched.o): Add $(HASHTAB_H).
	* sched-deps.c (sd_unresolve_dep): New function.
	* sched-int.h (struct haifa_sched_info): New fields save_state
	and restore_state.
	(struct _haifa_insn_data): New fields exact_tick, tick_estimate,
	feeds_backtrack_insn and shadow_p.
	(DO_BACKTRACKING): New value in enum SCHED_FLAGS.
	(sched_no_dce): Declare variable.
	(record_delay_slot_pair, free_delay_pairs, add_delay_dependencies,
	sd_unresolve_dep): Declare functions.
	* modulo-sched.c (sms_sched_info): Clear the two new fields.
	* sched-rgn.c (rgn_const_sched_info): Likewise.
	* sel-sched-ir.c (sched_sel_haifa_sched_info): Likewise.
	* sched-ebb.c (save_ebb_state, restore_ebb_state): New functions.
	(ebb_sched_info): Add them for the two new fields.
	(add_deps_for_risky_insns): Call add_delay_dependencies.

From-SVN: r176255

gcc/ChangeLog

+2011-07-14  Bernd Schmidt  <bernds@codesourcery.com>
+
+	* haifa-sched.c: Include "hashtab.h"
+	(sched_no_dce): New global variable.
+	(INSN_EXACT_TICK, INSN_TICK_ESTIMATE, FEEDS_BACKTRACK_INSN,
+	SHADOW_P): New macros.
+	(last_clock_var, cycle_issued_insns): Move declarations.
+	(must_backtrack): New static variable.
+	(struct delay_pair): New structure.
+	(delay_htab, delay_htab_i2): New static variables.
+	(delay_hash_i1, delay_hash_i2, delay_i1_eq, delay_i2_eq,
+	record_delay_slot_pair, pair_delay, add_delay_dependencies): New
+	functions.
+	(dep_cost_1): If delay pairs exist, try to look up the insns and
+	use the correct pair delay if we find them.
+	(rank-for_schedule): Tweak priority for insns that must be scheduled
+	soon to avoid backtracking.
+	(queue_insn): Detect conditions which force backtracking.
+	(ready_add): Likewise.
+	(struct sched_block_state): Add member shadows_only_p.
+	(struct haifa_save_data): New structure.
+	(backtrack_queue): New static variable.
+	(mark_backtrack_feeds, copy_insn_list, save_backtrack_point,
+	unschedule_insns_until, restore_last_backtrack_point,
+	free_topmost_backtrack_point, free_backtrack_queue,
+	estimate_insn_tick, estimate_shadow_tick): New functions.
+	(prune_ready_list): New arg shadows_only_p.  All callers changed.
+	If true, remove everything that isn't SHADOW_P.  Look up delay
+	pairs and estimate ticks to avoid scheduling the first insn too
+	early.
+	(verify_shadows): New function.
+	(schedule_block): Add machinery to enable backtracking.
+	(sched_init): Take sched_no_dce into account when setting
+	DF_LR_RUN_DCE.
+	(free_delay_pairs): New function.
+	(init_h_i_d): Initialize INSN_EXACT_TICK.
+	* Makefile.in (haifa-sched.o): Add $(HASHTAB_H).
+	* sched-deps.c (sd_unresolve_dep): New function.
+	* sched-int. (struct haifa_sched_info): New fields save_state
+	and restore_state.
+	(struct _haifa_insn_data): New fields exact_tick, tick_estimate,
+	feeds_backtrack_insn and shadow_p.
+	(DO_BACKTRACKING): New value in enum SCHED_FLAGS.
+	(sched_no_dce): Declare variable.
+	(record_delay_slot_pair, free_delay_pairs, add_delay_dependencies,
+	sd_unresolve_dep): Declare functions.
+	* modulo-sched.c (sms_sched_info): Clear the two new fields.
+	* sched-rgn.c (rgn_const_sched_info): Likewise.
+	* sel-sched-ir.c (sched_sel_haifa_sched_info): Likewise.
+	* sched-ebb.c (save_ebb_state, restore_ebb_state): New functions.
+	(ebb_sched_info): Add them for the two new fields.
+	(add_deps_for_risky_insns): Call add_delay_dependencies.
+
 2011-07-13  Michael Meissner  <meissner@linux.vnet.ibm.com>
 
 	* config/rs6000/rs6000.opt (-mpointers-to-nested-functions):

gcc/Makefile.in

@@ -3397,7 +3397,8 @@ modulo-sched.o : modulo-sched.c $(DDG_H) $(CONFIG_H) $(CONFIG_H) $(SYSTEM_H) \
 haifa-sched.o : haifa-sched.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) $(RTL_H) \
    $(SCHED_INT_H) $(REGS_H) hard-reg-set.h $(FLAGS_H) insn-config.h $(FUNCTION_H) \
    $(INSN_ATTR_H) $(DIAGNOSTIC_CORE_H) $(RECOG_H) $(EXCEPT_H) $(TM_P_H) $(TARGET_H) output.h \
-   $(PARAMS_H) $(DBGCNT_H) $(CFGLOOP_H) ira.h $(EMIT_RTL_H) $(COMMON_TARGET_H)
+   $(PARAMS_H) $(DBGCNT_H) $(CFGLOOP_H) ira.h $(EMIT_RTL_H) $(COMMON_TARGET_H) \
+   $(HASHTAB_H)
 sched-deps.o : sched-deps.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) \
    $(RTL_H) $(SCHED_INT_H) $(REGS_H) hard-reg-set.h $(FLAGS_H) insn-config.h \
    $(FUNCTION_H) $(INSN_ATTR_H) $(DIAGNOSTIC_CORE_H) $(RECOG_H) $(EXCEPT_H) cselib.h \

gcc/modulo-sched.c

@@ -283,6 +283,7 @@ static struct haifa_sched_info sms_sched_info =
   0, 0,
 
   NULL, NULL, NULL, NULL,
+  NULL, NULL,
   0
 };
 

gcc/sched-deps.c

@@ -1301,6 +1301,28 @@ sd_resolve_dep (sd_iterator_def sd_it)
 		 INSN_RESOLVED_FORW_DEPS (pro));
 }
 
+/* Perform the inverse operation of sd_resolve_dep.  Restore the dependence
+   pointed to by SD_IT to unresolved state.  */
+void
+sd_unresolve_dep (sd_iterator_def sd_it)
+{
+  dep_node_t node = DEP_LINK_NODE (*sd_it.linkp);
+  dep_t dep = DEP_NODE_DEP (node);
+  rtx pro = DEP_PRO (dep);
+  rtx con = DEP_CON (dep);
+
+  if ((current_sched_info->flags & DO_SPECULATION)
+      && (DEP_STATUS (dep) & SPECULATIVE))
+    move_dep_link (DEP_NODE_BACK (node), INSN_RESOLVED_BACK_DEPS (con),
+		   INSN_SPEC_BACK_DEPS (con));
+  else
+    move_dep_link (DEP_NODE_BACK (node), INSN_RESOLVED_BACK_DEPS (con),
+		   INSN_HARD_BACK_DEPS (con));
+
+  move_dep_link (DEP_NODE_FORW (node), INSN_RESOLVED_FORW_DEPS (pro),
+		 INSN_FORW_DEPS (pro));
+}
+
 /* Make TO depend on all the FROM's producers.
    If RESOLVED_P is true add dependencies to the resolved lists.  */
 void

gcc/sched-ebb.c

@@ -74,6 +74,25 @@ static void ebb_add_block (basic_block, basic_block);
 static basic_block advance_target_bb (basic_block, rtx);
 static void ebb_fix_recovery_cfg (int, int, int);
 
+/* Allocate memory and store the state of the frontend.  Return the allocated
+   memory.  */
+static void *
+save_ebb_state (void)
+{
+  int *p = XNEW (int);
+  *p = sched_rgn_n_insns;
+  return p;
+}
+
+/* Restore the state of the frontend from P_, then free it.  */
+static void
+restore_ebb_state (void *p_)
+{
+  int *p = (int *)p_;
+  sched_rgn_n_insns = *p;
+  free (p_);
+}
+
 /* Return nonzero if there are more insns that should be scheduled.  */
 
 static int
@@ -295,6 +314,10 @@ static struct haifa_sched_info ebb_sched_info =
   begin_schedule_ready,
   begin_move_insn,
   advance_target_bb,
+
+  save_ebb_state,
+  restore_ebb_state,
+
   SCHED_EBB
   /* We can create new blocks in begin_schedule_ready ().  */
   | NEW_BBS
@@ -377,76 +400,80 @@ add_deps_for_risky_insns (rtx head, rtx tail)
   basic_block last_block = NULL, bb;
 
   for (insn = head; insn != next_tail; insn = NEXT_INSN (insn))
-    if (control_flow_insn_p (insn))
-      {
-	bb = BLOCK_FOR_INSN (insn);
-	bb->aux = last_block;
-	last_block = bb;
-	last_jump = insn;
-      }
-    else if (INSN_P (insn) && last_jump != NULL_RTX)
-      {
-	classification = haifa_classify_insn (insn);
-	prev = last_jump;
-	switch (classification)
-	  {
-	  case PFREE_CANDIDATE:
-	    if (flag_schedule_speculative_load)
-	      {
-		bb = earliest_block_with_similiar_load (last_block, insn);
-		if (bb)
-		  {
-		    bb = (basic_block) bb->aux;
-		    if (!bb)
-		      break;
-		    prev = BB_END (bb);
-		  }
-	      }
-	    /* Fall through.  */
-	  case TRAP_RISKY:
-	  case IRISKY:
-	  case PRISKY_CANDIDATE:
-	    /* ??? We could implement better checking PRISKY_CANDIDATEs
-	       analogous to sched-rgn.c.  */
-	    /* We can not change the mode of the backward
-	       dependency because REG_DEP_ANTI has the lowest
-	       rank.  */
-	    if (! sched_insns_conditions_mutex_p (insn, prev))
-	      {
-		dep_def _dep, *dep = &_dep;
-
-		init_dep (dep, prev, insn, REG_DEP_ANTI);
-
-		if (!(current_sched_info->flags & USE_DEPS_LIST))
-		  {
-		    enum DEPS_ADJUST_RESULT res;
-
-		    res = sd_add_or_update_dep (dep, false);
-
-		    /* We can't change an existing dependency with
-		       DEP_ANTI.  */
-		    gcc_assert (res != DEP_CHANGED);
-		  }
-		else
-		  {
-		    if ((current_sched_info->flags & DO_SPECULATION)
-			&& (spec_info->mask & BEGIN_CONTROL))
-		      DEP_STATUS (dep) = set_dep_weak (DEP_ANTI, BEGIN_CONTROL,
-						       MAX_DEP_WEAK);
-
-		    sd_add_or_update_dep (dep, false);
-
-		    /* Dep_status could have been changed.
-		       No assertion here.  */
-		  }
-	      }
-
-            break;
-
-          default:
-            break;
-	  }
-      }
+    {
+      add_delay_dependencies (insn);
+      if (control_flow_insn_p (insn))
+	{
+	  bb = BLOCK_FOR_INSN (insn);
+	  bb->aux = last_block;
+	  last_block = bb;
+	  last_jump = insn;
+	}
+      else if (INSN_P (insn) && last_jump != NULL_RTX)
+	{
+	  classification = haifa_classify_insn (insn);
+	  prev = last_jump;
+
+	  switch (classification)
+	    {
+	    case PFREE_CANDIDATE:
+	      if (flag_schedule_speculative_load)
+		{
+		  bb = earliest_block_with_similiar_load (last_block, insn);
+		  if (bb)
+		    {
+		      bb = (basic_block) bb->aux;
+		      if (!bb)
+			break;
+		      prev = BB_END (bb);
+		    }
+		}
+	      /* Fall through.  */
+	    case TRAP_RISKY:
+	    case IRISKY:
+	    case PRISKY_CANDIDATE:
+	      /* ??? We could implement better checking PRISKY_CANDIDATEs
+		 analogous to sched-rgn.c.  */
+	      /* We can not change the mode of the backward
+		 dependency because REG_DEP_ANTI has the lowest
+		 rank.  */
+	      if (! sched_insns_conditions_mutex_p (insn, prev))
+		{
+		  dep_def _dep, *dep = &_dep;
+
+		  init_dep (dep, prev, insn, REG_DEP_ANTI);
+
+		  if (!(current_sched_info->flags & USE_DEPS_LIST))
+		    {
+		      enum DEPS_ADJUST_RESULT res;
+
+		      res = sd_add_or_update_dep (dep, false);
+
+		      /* We can't change an existing dependency with
+			 DEP_ANTI.  */
+		      gcc_assert (res != DEP_CHANGED);
+		    }
+		  else
+		    {
+		      if ((current_sched_info->flags & DO_SPECULATION)
+			  && (spec_info->mask & BEGIN_CONTROL))
+			DEP_STATUS (dep) = set_dep_weak (DEP_ANTI, BEGIN_CONTROL,
+							 MAX_DEP_WEAK);
+
+		      sd_add_or_update_dep (dep, false);
+
+		      /* Dep_status could have been changed.
+			 No assertion here.  */
+		    }
+		}
+
+	      break;
+
+	    default:
+	      break;
+	    }
+	}
+    }
   /* Maintain the invariant that bb->aux is clear after use.  */
   while (last_block)
     {

gcc/sched-int.h

@@ -603,6 +603,13 @@ struct haifa_sched_info
      The first parameter is the current basic block in EBB.  */
   basic_block (*advance_target_bb) (basic_block, rtx);
 
+  /* Allocate memory, store the frontend scheduler state in it, and
+     return it.  */
+  void *(*save_state) (void);
+  /* Restore frontend scheduler state from the argument, and free the
+     memory.  */
+  void (*restore_state) (void *);
+
   /* ??? FIXME: should use straight bitfields inside sched_info instead of
      this flag field.  */
   unsigned int flags;
@@ -762,10 +769,18 @@ struct _haifa_insn_data
      used to note timing constraints for the insns in the pending list.  */
   int tick;
 
+  /* For insns that are scheduled at a fixed difference from another,
+     this records the tick in which they must be ready.  */
+  int exact_tick;
+
   /* INTER_TICK is used to adjust INSN_TICKs of instructions from the
      subsequent blocks in a region.  */
   int inter_tick;
 
+  /* Used temporarily to estimate an INSN_TICK value for an insn given
+     current knowledge.  */
+  int tick_estimate;
+
   /* See comment on QUEUE_INDEX macro in haifa-sched.c.  */
   int queue_index;
 
@@ -775,6 +790,14 @@ struct _haifa_insn_data
      moved load insn and this one.  */
   unsigned int fed_by_spec_load : 1;
   unsigned int is_load_insn : 1;
+  /* Nonzero if this insn has negative-cost forward dependencies against
+     an already scheduled insn.  */
+  unsigned int feeds_backtrack_insn : 1;
+
+  /* Nonzero if this insn is a shadow of another, scheduled after a fixed
+     delay.  We only emit shadows at the end of a cycle, with no other
+     real insns following them.  */
+  unsigned int shadow_p : 1;
 
   /* '> 0' if priority is valid,
      '== 0' if priority was not yet computed,
@@ -1017,7 +1040,8 @@ enum SCHED_FLAGS {
      Results in generation of data and control speculative dependencies.
      Requires USE_DEPS_LIST set.  */
   DO_SPECULATION = USE_DEPS_LIST << 1,
-  SCHED_RGN = DO_SPECULATION << 1,
+  DO_BACKTRACKING = DO_SPECULATION << 1,
+  SCHED_RGN = DO_BACKTRACKING << 1,
   SCHED_EBB = SCHED_RGN << 1,
   /* Scheduler can possibly create new basic blocks.  Used for assertions.  */
   NEW_BBS = SCHED_EBB << 1,
@@ -1304,7 +1328,11 @@ extern int *ebb_head;
 extern int current_nr_blocks;
 extern int current_blocks;
 extern int target_bb;
+extern bool sched_no_dce;
 
+extern void record_delay_slot_pair (rtx, rtx, int);
+extern void free_delay_pairs (void);
+extern void add_delay_dependencies (rtx);
 extern bool sched_is_disabled_for_current_region_p (void);
 extern void sched_rgn_init (bool);
 extern void sched_rgn_finish (void);
@@ -1478,6 +1506,7 @@ extern dep_t sd_find_dep_between (rtx, rtx, bool);
 extern void sd_add_dep (dep_t, bool);
 extern enum DEPS_ADJUST_RESULT sd_add_or_update_dep (dep_t, bool);
 extern void sd_resolve_dep (sd_iterator_def);
+extern void sd_unresolve_dep (sd_iterator_def);
 extern void sd_copy_back_deps (rtx, rtx, bool);
 extern void sd_delete_dep (sd_iterator_def);
 extern void sd_debug_lists (rtx, sd_list_types_def);

gcc/sched-rgn.c

@@ -2371,6 +2371,7 @@ static const struct haifa_sched_info rgn_const_sched_info =
   begin_schedule_ready,
   NULL,
   advance_target_bb,
+  NULL, NULL,
   SCHED_RGN
 };
 

gcc/sel-sched-ir.c

@@ -5700,6 +5700,10 @@ static struct haifa_sched_info sched_sel_haifa_sched_info =
   NULL, /* begin_schedule_ready */
   NULL, /* begin_move_insn */
   NULL, /* advance_target_bb */
+
+  NULL,
+  NULL,
+
   SEL_SCHED | NEW_BBS
 };