tree-ssa-loop-ivcanon.c: New file.

	* tree-ssa-loop-ivcanon.c: New file.
	* tree-ssa-loop-manip.c (create_iv): New function.
	* Makefile.in (tree-ssa-loop-ivcanon.o): Add.
	(tree-ssa-loop.o, tree-ssa-loop-manip.o): Add SCEV_H dependency.
	* cfgloop.c (mark_single_exit_loops): New function.
	(verify_loop_structure): Verify single-exit loops.
	* cfgloop.h (struct loop): Add single_exit field.
	(LOOPS_HAVE_MARKED_SINGLE_EXITS): New constant.
	(mark_single_exit_loops): Declare.
	(tree_num_loop_insns): Declare.
	* cfgloopmanip.c (update_single_exits_after_duplication): New function.
	(duplicate_loop_to_header_edge): Use it.
	* common.opt (fivcanon): New flag.
	* timevar.def (TV_TREE_LOOP_IVCANON, TV_COMPLETE_UNROLL): New timevars.
	* tree-cfg.c (tree_find_edge_insert_loc): Return newly created block.
	(bsi_commit_edge_inserts_1): Pass null to tree_find_edge_insert_loc.
	(bsi_insert_on_edge_immediate): New function.
	* tree-flow.h (bsi_insert_on_edge_immediate,
	canonicalize_induction_variables, tree_unroll_loops_completely,
	create_iv): Declare.
	* tree-optimize.c (init_tree_optimization_passes): Add
	pass_iv_canon and pass_complete_unroll.
	* tree-pass.h (pass_iv_canon, pass_complete_unroll): Declare.
	* tree-scalar-evolution.c (get_loop_exit_condition,
	get_exit_conditions_rec, number_of_iterations_in_loop,
	scev_initialize): Use single_exit information.
	* tree-ssa-loop-niter.c (number_of_iterations_cond): Record
	missing assumptions.
	(loop_niter_by_eval):  Return number of iterations as unsigned
	int.
	* tree-ssa-loop.c (tree_ssa_loop_init): Mark single exit loops.
	(tree_ssa_loop_ivcanon, gate_tree_ssa_loop_ivcanon, pass_iv_canon,
	tree_complete_unroll, gate_tree_complete_unroll, pass_complete_unroll):
	New passes.
	(tree_ssa_loop_done): Call free_numbers_of_iterations_estimates.
	* tree-ssanames.c (make_ssa_name): Allow creating ssa name before
	the defining statement is ready.
	* tree-vectorizer.c (vect_create_iv_simple): Removed.
	(vect_create_index_for_array_ref, vect_transform_loop_bound):
	Use create_iv.
	(vect_transform_loop_bound): Use single_exit information.
	(vect_analyze_loop_form): Cleanup bogus tests.
	(vectorize_loops): Do not call flow_loop_scan.
	* tree.h (may_negate_without_overflow_p): Declare.
	* fold-const.c (may_negate_without_overflow_p): Split out from ...
	(negate_expr_p): ... this function.
	(tree_expr_nonzero_p): Handle overflowed constants correctly.
	* doc/invoke.texi (-fivcanon): Document.
	* doc/passes.texi: Document canonical induction variable creation.

	* gcc.dg/tree-ssa/loop-1.c: New test.

From-SVN: r86516

1 files changed, 72 insertions, 2 deletions

diff --git a/gcc/tree-ssa-loop.c b/gcc/tree-ssa-loop.c
index 666dab6..5b5ec05 100644
--- a/gcc/tree-ssa-loop.c
+++ b/gcc/tree-ssa-loop.c
@@ -101,6 +101,10 @@ tree_ssa_loop_init (void)
   current_loops = tree_loop_optimizer_init (dump_file);
   if (!current_loops)
     return;
+
+  /* Find the loops that are exited just through a single edge.  */
+  mark_single_exit_loops (current_loops);
+
   scev_initialize (current_loops);
 }
   
@@ -187,6 +191,72 @@ struct tree_opt_pass pass_vectorize =
   TODO_dump_func			/* todo_flags_finish */
 };
 
+/* Canonical induction variable creation pass.  */
+
+static void
+tree_ssa_loop_ivcanon (void)
+{
+  if (!current_loops)
+    return;
+
+  canonicalize_induction_variables (current_loops);
+}
+
+static bool
+gate_tree_ssa_loop_ivcanon (void)
+{
+  return flag_ivcanon != 0;
+}
+
+struct tree_opt_pass pass_iv_canon =
+{
+  "ivcanon",				/* name */
+  gate_tree_ssa_loop_ivcanon,		/* gate */
+  tree_ssa_loop_ivcanon,	       	/* execute */
+  NULL,					/* sub */
+  NULL,					/* next */
+  0,					/* static_pass_number */
+  TV_TREE_LOOP_IVCANON,	  		/* tv_id */
+  PROP_cfg | PROP_ssa,			/* properties_required */
+  0,					/* properties_provided */
+  0,					/* properties_destroyed */
+  0,					/* todo_flags_start */
+  TODO_dump_func                	/* todo_flags_finish */
+};
+
+/* Complete unrolling of loops.  */
+
+static void
+tree_complete_unroll (void)
+{
+  if (!current_loops)
+    return;
+
+  tree_unroll_loops_completely (current_loops);
+}
+
+static bool
+gate_tree_complete_unroll (void)
+{
+  return flag_unroll_loops != 0;
+}
+
+struct tree_opt_pass pass_complete_unroll =
+{
+  "cunroll",				/* name */
+  gate_tree_complete_unroll,		/* gate */
+  tree_complete_unroll,		       	/* execute */
+  NULL,					/* sub */
+  NULL,					/* next */
+  0,					/* static_pass_number */
+  TV_COMPLETE_UNROLL,	  		/* tv_id */
+  PROP_cfg | PROP_ssa,			/* properties_required */
+  0,					/* properties_provided */
+  0,					/* properties_destroyed */
+  0,					/* todo_flags_start */
+  TODO_dump_func                	/* todo_flags_finish */
+};
+
 /* Loop optimizer finalization.  */
 
 static void
@@ -195,12 +265,12 @@ tree_ssa_loop_done (void)
   if (!current_loops)
     return;
 
-  scev_finalize ();
-
 #ifdef ENABLE_CHECKING
   verify_loop_closed_ssa ();
 #endif
 
+  free_numbers_of_iterations_estimates (current_loops);
+  scev_finalize ();
   loop_optimizer_finalize (current_loops,
 			   (dump_flags & TDF_DETAILS ? dump_file : NULL));
   current_loops = NULL;