function.h (has_bb_partition): New rtl_data flag.

2013-05-15  Teresa Johnson  <tejohnson@google.com>

	* function.h (has_bb_partition): New rtl_data flag.
        (bb_reorder_complete): Ditto.
	* cfgcleanup.c (try_crossjump_to_edge): Check for has_bb_partition
        instead of flag_reorder_blocks_and_partition.
        * cfgrtl.c (verify_hot_cold_block_grouping): Moved from bb-reorder.c,
        with some enhancements.
        (rtl_verify_flow_info_1): Call verify_hot_cold_block_grouping.
	* bb-reorder.c (connect_traces): Check for has_bb_partition
        instead of flag_reorder_blocks_and_partition.
	(verify_hot_cold_block_grouping): Moved to cfgrtl.c.
	(reorder_basic_blocks): Set bb_reorder_complete flag, remove call to
        verify_hot_cold_block_grouping.
	(partition_hot_cold_basic_blocks): Set has_bb_partition.

From-SVN: r198934

gcc/ChangeLog

+2013-05-15  Teresa Johnson  <tejohnson@google.com>
+
+	* function.h (has_bb_partition): New rtl_data flag.
+	(bb_reorder_complete): Ditto.
+	* cfgcleanup.c (try_crossjump_to_edge): Check for has_bb_partition
+	instead of flag_reorder_blocks_and_partition.
+	* cfgrtl.c (verify_hot_cold_block_grouping): Moved from bb-reorder.c,
+	with some enhancements.
+	(rtl_verify_flow_info_1): Call verify_hot_cold_block_grouping.
+	* bb-reorder.c (connect_traces): Check for has_bb_partition
+	instead of flag_reorder_blocks_and_partition.
+	(verify_hot_cold_block_grouping): Moved to cfgrtl.c.
+	(reorder_basic_blocks): Set bb_reorder_complete flag, remove call to
+	verify_hot_cold_block_grouping.
+	(partition_hot_cold_basic_blocks): Set has_bb_partition.
+
 2013-05-15  Ramana Radhakrishnan  <ramana.radhakrishnan@arm.com>
 
 	PR target/19599

gcc/bb-reorder.c

@@ -1053,7 +1053,7 @@ connect_traces (int n_traces, struct trace *traces)
   current_partition = BB_PARTITION (traces[0].first);
   two_passes = false;
 
-  if (flag_reorder_blocks_and_partition)
+  if (crtl->has_bb_partition)
     for (i = 0; i < n_traces && !two_passes; i++)
       if (BB_PARTITION (traces[0].first)
 	  != BB_PARTITION (traces[i].first))
@@ -1262,7 +1262,7 @@ connect_traces (int n_traces, struct trace *traces)
 		      }
 		  }
 
-	      if (flag_reorder_blocks_and_partition)
+	      if (crtl->has_bb_partition)
 		try_copy = false;
 
 	      /* Copy tiny blocks always; copy larger blocks only when the
@@ -2068,43 +2068,6 @@ add_reg_crossing_jump_notes (void)
 	add_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX);
 }
 
-/* Verify, in the basic block chain, that there is at most one switch
-   between hot/cold partitions. This is modelled on
-   rtl_verify_flow_info_1, but it cannot go inside that function
-   because this condition will not be true until after
-   reorder_basic_blocks is called.  */
-
-static void
-verify_hot_cold_block_grouping (void)
-{
-  basic_block bb;
-  int err = 0;
-  bool switched_sections = false;
-  int current_partition = 0;
-
-  FOR_EACH_BB (bb)
-    {
-      if (!current_partition)
-	current_partition = BB_PARTITION (bb);
-      if (BB_PARTITION (bb) != current_partition)
-	{
-	  if (switched_sections)
-	    {
-	      error ("multiple hot/cold transitions found (bb %i)",
-		     bb->index);
-	      err = 1;
-	    }
-	  else
-	    {
-	      switched_sections = true;
-	      current_partition = BB_PARTITION (bb);
-	    }
-	}
-    }
-
-  gcc_assert(!err);
-}
-
 /* Reorder basic blocks.  The main entry point to this file.  FLAGS is
    the set of flags to pass to cfg_layout_initialize().  */
 
@@ -2157,8 +2120,9 @@ reorder_basic_blocks (void)
       dump_flow_info (dump_file, dump_flags);
     }
 
-  if (flag_reorder_blocks_and_partition)
-    verify_hot_cold_block_grouping ();
+  /* Signal that rtl_verify_flow_info_1 can now verify that there
+     is at most one switch between hot/cold sections.  */
+  crtl->bb_reorder_complete = true;
 }
 
 /* Determine which partition the first basic block in the function
@@ -2503,6 +2467,8 @@ partition_hot_cold_basic_blocks (void)
   if (!crossing_edges.exists ())
     return 0;
 
+  crtl->has_bb_partition = true;
+
   /* Make sure the source of any crossing edge ends in a jump and the
      destination of any crossing edge has a label.  */
   add_labels_and_missing_jumps (crossing_edges);

gcc/cfgcleanup.c

@@ -1864,7 +1864,7 @@ try_crossjump_to_edge (int mode, edge e1, edge e2,
      partition boundaries).  See the comments at the top of
      bb-reorder.c:partition_hot_cold_basic_blocks for complete details.  */
 
-  if (flag_reorder_blocks_and_partition && reload_completed)
+  if (crtl->has_bb_partition && reload_completed)
     return false;
 
   /* Search backward through forwarder blocks.  We don't need to worry

gcc/cfgrtl.c

@@ -2058,6 +2058,44 @@ get_last_bb_insn (basic_block bb)
 
   return end;
 }
+
+/* Verify, in the basic block chain, that there is at most one switch
+   between hot/cold partitions. This condition will not be true until
+   after reorder_basic_blocks is called.  */
+
+static void
+verify_hot_cold_block_grouping (void)
+{
+  basic_block bb;
+  int err = 0;
+  bool switched_sections = false;
+  int current_partition = BB_UNPARTITIONED;
+
+  if (!crtl->bb_reorder_complete)
+    return;
+
+  FOR_EACH_BB (bb)
+    {
+      if (current_partition != BB_UNPARTITIONED
+          && BB_PARTITION (bb) != current_partition)
+	{
+	  if (switched_sections)
+	    {
+	      error ("multiple hot/cold transitions found (bb %i)",
+		     bb->index);
+	      err = 1;
+	    }
+	  else
+            switched_sections = true;
+
+          if (!crtl->has_bb_partition)
+            error ("partition found but function partition flag not set");
+	}
+      current_partition = BB_PARTITION (bb);
+    }
+
+  gcc_assert(!err);
+}
 
 /* Verify the CFG and RTL consistency common for both underlying RTL and
    cfglayout RTL.
@@ -2072,6 +2110,7 @@ get_last_bb_insn (basic_block bb)
      and NOTE_INSN_BASIC_BLOCK
    - verify that no fall_thru edge crosses hot/cold partition boundaries
    - verify that there are no pending RTL branch predictions
+   - verify that there is a single hot/cold partition boundary after bbro
 
    In future it can be extended check a lot of other stuff as well
    (reachability of basic blocks, life information, etc. etc.).  */
@@ -2323,6 +2362,8 @@ rtl_verify_flow_info_1 (void)
 	  }
     }
 
+  verify_hot_cold_block_grouping();
+
   /* Clean up.  */
   return err;
 }

gcc/function.h

@@ -446,6 +446,15 @@ struct GTY(()) rtl_data {
      sched2) and is useful only if the port defines LEAF_REGISTERS.  */
   bool uses_only_leaf_regs;
 
+  /* Nonzero if the function being compiled has undergone hot/cold partitioning
+     (under flag_reorder_blocks_and_partition) and has at least one cold
+     block.  */
+  bool has_bb_partition;
+
+  /* Nonzero if the function being compiled has completed the bb reordering
+     pass.  */
+  bool bb_reorder_complete;
+
   /* Like regs_ever_live, but 1 if a reg is set or clobbered from an
      asm.  Unlike regs_ever_live, elements of this array corresponding
      to eliminable regs (like the frame pointer) are set if an asm