This patch fixes an lto profiledbootstrap failure with

-freorder-blocks-and-partition enabled. Currently compgotos
is the only pass that goes into cfglayout mode after bb reordering,
which is undesireable (and in the case of -freorder-blocks-and-partition
can cause illegal partitioning) because of the optimizations performed
on the cfg when going into cfglayout mode. Moved compgoto before
bb reordering to avoid these problems.

2013-11-18  Teresa Johnson  <tejohnson@google.com>

	* gcc/cfgrtl.c (cfg_layout_initialize): Assert if we
	try to go into cfglayout after bb reordering.
	* gcc/passes.def: Move compgotos before bb reordering
	since it goes into cfglayout.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@204985 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 498f780..d49af50 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2013-11-18  Teresa Johnson  <tejohnson@google.com>
+
+       * gcc/cfgrtl.c (cfg_layout_initialize): Assert if we
+       try to go into cfglayout after bb reordering.
+       * gcc/passes.def: Move compgotos before bb reordering
+       since it goes into cfglayout.
+
 2013-11-18  Bernd Schmidt  <bernds@codesourcery.com>
 
        * cgraphunit.c (ipa_passes): Don't execute all_lto_gen_passes.

diff --git a/gcc/cfgrtl.c b/gcc/cfgrtl.c
index c7ee7ee..1f99aa1 100644 (file)
--- a/gcc/cfgrtl.c
+++ b/gcc/cfgrtl.c
@@ -4204,6 +4204,15 @@ cfg_layout_initialize (unsigned int flags)
   rtx x;
   basic_block bb;
 
+  /* Once bb reordering is complete, cfg layout mode should not be re-entered.
+     Entering cfg layout mode will perform optimizations on the cfg that
+     could affect the bb layout negatively or even require fixups. An
+     example of the latter is if edge forwarding performed when optimizing
+     the cfg layout required moving a block from the hot to the cold section
+     under -freorder-blocks-and-partition. This would create an illegal
+     partitioning unless some manual fixup was performed.  */
+  gcc_assert (!crtl->bb_reorder_complete);
+
   initialize_original_copy_tables ();
 
   cfg_layout_rtl_register_cfg_hooks ();

diff --git a/gcc/passes.def b/gcc/passes.def
index 8480991..0aba1d9 100644 (file)
--- a/gcc/passes.def
+++ b/gcc/passes.def
@@ -382,6 +382,7 @@ along with GCC; see the file COPYING3.  If not see
          NEXT_PASS (pass_regrename);
          NEXT_PASS (pass_cprop_hardreg);
          NEXT_PASS (pass_fast_rtl_dce);
+         NEXT_PASS (pass_duplicate_computed_gotos);
          NEXT_PASS (pass_reorder_blocks);
          NEXT_PASS (pass_branch_target_load_optimize2);
          NEXT_PASS (pass_leaf_regs);
@@ -393,7 +394,6 @@ along with GCC; see the file COPYING3.  If not see
              NEXT_PASS (pass_stack_regs_run);
          POP_INSERT_PASSES ()
          NEXT_PASS (pass_compute_alignments);
-         NEXT_PASS (pass_duplicate_computed_gotos);
          NEXT_PASS (pass_variable_tracking);
          NEXT_PASS (pass_free_cfg);
          NEXT_PASS (pass_machine_reorg);