* cgraph.h (symtab_node_base): Add definition, alias and analyzed

	flags; reorder rest of fields in more consistent way.
	(varpool_node): Remove analyzed, finalized and alias.
	(cgraph_ndoe): Likewise.
	(symtab_alias_ultimate_target): New function.
	(cgraph_function_node): Move offline.
	(cgraph_reset_node): Declare.
	(cgraph_comdat_can_be_unshared_p): Remove.
	(varpool_remove_initializer): Declare.
	(varpool_first_defined_variable, varpool_next_defined_variable
	cgraph_first_defined_function, cgraph_next_defined_function): Update.
	(cgraph_function_with_gimple_body_p): Update.
	(varpool_all_refs_explicit_p): Update.
	(symtab_alias_target): New function.
	(cgraph_alias_aliased_node, varpool_alias_aliased_node): Rename to ...
	(cgraph_alias_target, varpool_alias_target): .. this one; simplify.
	(cgraph_function_or_thunk_node): Simplify using symtab_alias_ultimate_target.
	(varpool_variable_node): Likewise.
	* cgraph.c (cgraph_create_function_alias): Update.
	(cgraph_add_thunk): Update.
	(cgraph_remove_node): Update.
	(dump_cgraph_node): Do not dump removed flags.
	(cgraph_function_body_availability): Update.
	(cgraph_propagate_frequency): Update.
	(verify_cgraph_node): Check sanity of local flag.
	(cgraph_function_node): Move here from cgraph.h; revamp for
	cgraph_function_or_thunk_node.
	* lto-symtab.c (lto_varpool_replace_node): Update.
	(lto_symtab_resolve_can_prevail_p): Update.
	(lto_symtab_merge_cgraph_nodes): Update.
	* ipa-cp.c (determine_versionability, initialize_node_lattices,
	propagate_constants_accross_call, devirtualization_time_bonus,
	ipcp_propagate_stage): Update.
	* tree-emutls.c (create_emultls_var, ipa_lower_emutls): Update.
	* ipa-inline-transform.c (clone_inlined_nodes, preserve_function_body_p): Update.
	* ipa-reference.c (propagate): Update.
	(write_node_summary_p): Update.
	* toplev.c (wrapup_global_declaration_2): Update.
	* cgraphunit.c (cgraph_analyze_function): Rename to ...
	(analyze_function) ... this one.
	(cgraph_process_new_functions): Update.
	(cgraph_reset_node): Export.
	(cgraph_finalize_function): Update.
	(cgraph_add_new_function): Update.
	(process_function_and_variable_attributes): Update.
	(varpool_finalize_decl): Update.
	(symbol_finalized): Remove.
	(symbol_finalized_and_needed): Rename to ...
	(symbol_defined_and_needed): ... update.
	(cgraph_analyze_functions): Update.
	(handle_alias_pairs): Update.
	(mark_functions_to_output): Update.
	(assemble_thunk): Update.
	(output_in_order): Update.
	(output_weakrefs): Update.
	(finalize_compilation_unit): Update.
	* lto-cgraph.c (reachable_from_other_partition_p, lto_output_node,
	lto_output_varpool_node, compute_ltrans_boundary, input_overwrite_node,
	input_node, input_varpool_node): Update.
	* dbxout.c (dbxout_expand_expr): Update.
	* cgraphclones.c (cgraph_clone_node): Update.
	(cgraph_copy_node_for_versioning): Update.
	(cgraph_materialize_clone): Update.
	(cgraph_materialize_all_clones): Update.
	* ipa-pure-const.c (analyze_function, pure_const_write_summary,
	propagate_pure_const, propagate_nothrow): Update.
	* lto-streamer-out.c (lto_output, write_symbol): Update.
	* ipa-utils.c (ipa_reverse_postorder): Update.
	* ipa-inline.c (can_inline_edge_p): Update.
	(update_caller_keys, ipa_inline): Update.
	* dwarf2out.c (reference_to_unused,
	premark_types_used_by_global_vars_helper): Update.
	* tree-eh.c (tree_could_trap_p): Update.
	* ipa-split.c (consider_split, execute_split_functions): Update.
	* ipa.c (cgraph_non_local_node_p_1, cgraph_local_node_p,
	 has_addr_references_p): Update;
	move ahead in file for better readability.
	(process_references): Simplify.
	(symtab_remove_unreachable_nodes): Update; cleanup way function/var
	bodies are removed.
	(cgraph_comdat_can_be_unshared_p): Make static.
	(cgraph_externally_visible_p): Update.
	(varpool_externally_visible_p): Update.
	(function_and_variable_visibility): Update.
	* trans-mem.c (get_cg_data, ipa_tm_mayenterirr_function,
	ipa_tm_mark_force_output_node): Update.
	* ipa-inline-analysis.c (dump_inline_summary, initialize_inline_failed,
	estimate_edge_devirt_benefit, inline_generate_summary,
	inline_write_summary): Update.
	* gimple-fold.c (can_refer_decl_in_current_unit_p): Update.
	* ipa-prop.c (ipa_compute_jump_functions): Update.
	(ipa_print_node_params, ipa_prop_read_section, ipa_update_after_lto_read,
	read_replacements_section): Update.
	* varasm.c (mark_decl_referenced): Update.
	(assemble_alias, dump_tm_clone_pairs): Update.
	* tree-inline.c (copy_bb): Update.
	(estimate_num_insns, optimize_inline_calls, tree_function_versioning):
	Update.
	* symtab.c (dump_symtab_base): Print new flags.
	(verify_symtab_base): Verify new flags.
	(symtab_alias_ultimate_target): New function.
	* tree-ssa-structalias.c (get_constraint_for_ssa_var,
	create_variable_info_for, associate_varinfo_to_alias, ipa_pta_execute):
	Update.
	* passes.c (ipa_write_summaries, ipa_write_optimization_summaries): Update.
	* i386.c (ix86_get_function_versions_dispatcher,
	ix86_generate_version_dispatcher_body): Update.
	(fold_builtin_cpu): Use varpool_add_new_variable.
	* varpool.c (varpool_remove_initializer): Break out from ...
	(varpool_remove_node): ... this one.
	(dump_varpool_node, varpool_node_for_asm,
	cgraph_variable_initializer_availability, varpool_analyze_node,
	varpool_assemble_decl, varpool_remove_unreferenced_decls,
	varpool_finalize_named_section_flags, varpool_create_variable_alias): Update

	* decl.c (java_mark_decl_local): Update for new symtab flags.

	* tree.c (cp_fix_function_decl_p): Update for new symtab flags.
	* decl2.c )var_finalized_p, cp_write_global_declarations): Likewise.

	* lto.c (has_analyzed_clone_p, lto_materialize_function): Update for new symtab
	flags.
	* lto-partition.c (get_symbol_class, lto_balanced_map): Likewise.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@199422 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 34 insertions, 6 deletions

diff --git a/gcc/ipa-split.c b/gcc/ipa-split.c
index 107c7a90d95..e786478981e 100644
--- a/gcc/ipa-split.c
+++ b/gcc/ipa-split.c
@@ -367,23 +367,46 @@ consider_split (struct split_point *current, bitmap non_ssa_vars,
   unsigned int i;
   int incoming_freq = 0;
   tree retval;
+  bool back_edge = false;
 
   if (dump_file && (dump_flags & TDF_DETAILS))
     dump_split_point (dump_file, current);
 
   FOR_EACH_EDGE (e, ei, current->entry_bb->preds)
-    if (!bitmap_bit_p (current->split_bbs, e->src->index))
-      incoming_freq += EDGE_FREQUENCY (e);
+    {
+      if (e->flags & EDGE_DFS_BACK)
+	back_edge = true;
+      if (!bitmap_bit_p (current->split_bbs, e->src->index))
+        incoming_freq += EDGE_FREQUENCY (e);
+    }
 
   /* Do not split when we would end up calling function anyway.  */
   if (incoming_freq
       >= (ENTRY_BLOCK_PTR->frequency
 	  * PARAM_VALUE (PARAM_PARTIAL_INLINING_ENTRY_PROBABILITY) / 100))
     {
-      if (dump_file && (dump_flags & TDF_DETAILS))
-	fprintf (dump_file,
-		 "  Refused: incoming frequency is too large.\n");
-      return;
+      /* When profile is guessed, we can not expect it to give us
+	 realistic estimate on likelyness of function taking the
+	 complex path.  As a special case, when tail of the function is
+	 a loop, enable splitting since inlining code skipping the loop
+	 is likely noticeable win.  */
+      if (back_edge
+	  && profile_status != PROFILE_READ
+	  && incoming_freq < ENTRY_BLOCK_PTR->frequency)
+	{
+	  if (dump_file && (dump_flags & TDF_DETAILS))
+	    fprintf (dump_file,
+		     "  Split before loop, accepting despite low frequencies %i %i.\n",
+		     incoming_freq,
+		     ENTRY_BLOCK_PTR->frequency);
+	}
+      else
+	{
+	  if (dump_file && (dump_flags & TDF_DETAILS))
+	    fprintf (dump_file,
+		     "  Refused: incoming frequency is too large.\n");
+	  return;
+	}
     }
 
   if (!current->header_size)
@@ -1533,6 +1556,11 @@ execute_split_functions (void)
       return 0;
     }
 
+  /* We enforce splitting after loop headers when profile info is not
+     available.  */
+  if (profile_status != PROFILE_READ)
+    mark_dfs_back_edges ();
+
   /* Initialize bitmap to track forbidden calls.  */
   forbidden_dominators = BITMAP_ALLOC (NULL);
   calculate_dominance_info (CDI_DOMINATORS);