2009-01-05 Vladimir Makarov <vmakarov@redhat.com>

	PR rtl-optimization/38583
	* params.h (IRA_MAX_CONFLICT_TABLE_SIZE): New macro.

	* params.def (ira-max-conflict-table-size): New.

	* doc/invoke.texi (ira-max-conflict-table-size): Decribe.
	
	* ira.h (ira_conflicts_p): New external definition.
	
	* ira-conflicts.c (build_conflict_bit_table): Do not build too big
	table.  Report this.  Return result of building.
	(ira_build_conflicts): Use ira_conflicts_p.  Check result of
	building conflict table.

	* ira-color.c (fast_allocation): Use num instead of
	ira_allocnos_num.
	(ira_color): Use ira_conflicts_p.
	
	* global.c: Include ira.h.
	(pseudo_for_reload_consideration_p, build_insn_chain): Use
	ira_conflicts_p.

	* Makefile.in (global.o): Add ira.h.
	
	* ira-build.c (mark_all_loops_for_removal,
	propagate_some_info_from_allocno): New.
	(remove_unnecessary_allocnos): Call
	propagate_some_info_from_allocno.
	(remove_low_level_allocnos): New.
	(remove_unnecessary_regions): Add parameter.  Call
	mark_all_loops_for_removal and remove_low_level_allocnos.  Pass
	parameter to remove_unnecessary_regions.
	(ira_build): Remove all regions but root if the conflict table was
	not built.  Update conflict hard regs for allocnos crossing calls.

	* ira.c (ira_conflicts_p): New global.
	(ira): Define and use ira_conflicts_p.

	* reload1.c (compute_use_by_pseudos, reload, count_pseudo,
	count_spilled_pseudo, find_reg, alter_reg, finish_spills,
	emit_input_reload_insns, delete_output_reload): Use
	ira_conflicts_p.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@143112 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 47 insertions, 18 deletions

diff --git a/gcc/ira-conflicts.c b/gcc/ira-conflicts.c
index ff116b5da8a..244d3bc9b3e 100644
--- a/gcc/ira-conflicts.c
+++ b/gcc/ira-conflicts.c
@@ -60,8 +60,10 @@ static IRA_INT_TYPE **conflicts;
 
 
 
-/* Build allocno conflict table by processing allocno live ranges.  */
-static void
+/* Build allocno conflict table by processing allocno live ranges.
+   Return true if the table was built.  The table is not built if it
+   is too big.  */
+static bool
 build_conflict_bit_table (void)
 {
   int i, num, id, allocated_words_num, conflict_bit_vec_words_num;
@@ -74,6 +76,26 @@ build_conflict_bit_table (void)
   int allocno_set_words;
 
   allocno_set_words = (ira_allocnos_num + IRA_INT_BITS - 1) / IRA_INT_BITS;
+  allocated_words_num = 0;
+  FOR_EACH_ALLOCNO (allocno, ai)
+    {
+      if (ALLOCNO_MAX (allocno) < ALLOCNO_MIN (allocno))
+	  continue;
+      conflict_bit_vec_words_num
+	= ((ALLOCNO_MAX (allocno) - ALLOCNO_MIN (allocno) + IRA_INT_BITS)
+	   / IRA_INT_BITS);
+      allocated_words_num += conflict_bit_vec_words_num;
+      if ((unsigned long long) allocated_words_num * sizeof (IRA_INT_TYPE)
+	  > (unsigned long long) IRA_MAX_CONFLICT_TABLE_SIZE * 1024 * 1024)
+	{
+	  if (internal_flag_ira_verbose > 0 && ira_dump_file != NULL)
+	    fprintf
+	      (ira_dump_file,
+	       "+++Conflict table will be too big(>%dMB) -- don't use it\n",
+	       IRA_MAX_CONFLICT_TABLE_SIZE);
+	  return false;
+	}
+    }
   allocnos_live = sparseset_alloc (ira_allocnos_num);
   conflicts = (IRA_INT_TYPE **) ira_allocate (sizeof (IRA_INT_TYPE *)
 					      * ira_allocnos_num);
@@ -134,6 +156,7 @@ build_conflict_bit_table (void)
 	sparseset_clear_bit (allocnos_live, ALLOCNO_NUM (r->allocno));
     }
   sparseset_free (allocnos_live);
+  return true;
 }
 
 
@@ -743,29 +766,34 @@ ira_build_conflicts (void)
   ira_allocno_iterator ai;
   HARD_REG_SET temp_hard_reg_set;
 
-  if (optimize)
+  if (ira_conflicts_p)
     {
-      build_conflict_bit_table ();
-      build_conflicts ();
-      ira_traverse_loop_tree (true, ira_loop_tree_root, NULL, add_copies);
-      /* We need finished conflict table for the subsequent call.  */
-      if (flag_ira_region == IRA_REGION_ALL
-	  || flag_ira_region == IRA_REGION_MIXED)
-	propagate_copies ();
-      /* Now we can free memory for the conflict table (see function
-	 build_allocno_conflicts for details).  */
-      FOR_EACH_ALLOCNO (a, ai)
+      ira_conflicts_p = build_conflict_bit_table ();
+      if (ira_conflicts_p)
 	{
-	  if (ALLOCNO_CONFLICT_ALLOCNO_ARRAY (a) != conflicts[ALLOCNO_NUM (a)])
-	    ira_free (conflicts[ALLOCNO_NUM (a)]);
+	  build_conflicts ();
+	  ira_traverse_loop_tree (true, ira_loop_tree_root, NULL, add_copies);
+	  /* We need finished conflict table for the subsequent call.  */
+	  if (flag_ira_region == IRA_REGION_ALL
+	      || flag_ira_region == IRA_REGION_MIXED)
+	    propagate_copies ();
+	  /* Now we can free memory for the conflict table (see function
+	     build_allocno_conflicts for details).  */
+	  FOR_EACH_ALLOCNO (a, ai)
+	    {
+	      if (ALLOCNO_CONFLICT_ALLOCNO_ARRAY (a)
+		  != conflicts[ALLOCNO_NUM (a)])
+		ira_free (conflicts[ALLOCNO_NUM (a)]);
+	    }
+	  ira_free (conflicts);
 	}
-      ira_free (conflicts);
     }
   if (! CLASS_LIKELY_SPILLED_P (BASE_REG_CLASS))
     CLEAR_HARD_REG_SET (temp_hard_reg_set);
   else
     {
-      COPY_HARD_REG_SET (temp_hard_reg_set, reg_class_contents[BASE_REG_CLASS]);
+      COPY_HARD_REG_SET (temp_hard_reg_set,
+			 reg_class_contents[BASE_REG_CLASS]);
       AND_COMPL_HARD_REG_SET (temp_hard_reg_set, ira_no_alloc_regs);
       AND_HARD_REG_SET (temp_hard_reg_set, call_used_reg_set);
     }
@@ -796,6 +824,7 @@ ira_build_conflicts (void)
 	    }
 	}
     }
-  if (optimize && internal_flag_ira_verbose > 2 && ira_dump_file != NULL)
+  if (optimize && ira_conflicts_p
+      && internal_flag_ira_verbose > 2 && ira_dump_file != NULL)
     print_conflicts (ira_dump_file, false);
 }