* cfgloopanal.c (get_loop_hot_path): New function.

	* tree-ssa-lop-ivcanon.c (struct loop_size): Add CONSTANT_IV,
	NUM_NON_PURE_CALLS_ON_HOT_PATH, NUM_PURE_CALLS_ON_HOT_PATH,
	NUM_BRANCHES_ON_HOT_PATH.
	(tree_estimate_loop_size): Compute the new values.
	(try_unroll_loop_completely): Disable unrolling of loops with only
	calls or too many branches.
	(tree_unroll_loops_completely): Deal also with outer loops of hot loops.
	* cfgloop.h (get_loop_hot_path): Declare.
	* params.def (PARAM_MAX_PEEL_BRANCHES): New parameters.
	* invoke.texi (max-peel-branches): Document.

	* gcc.dg/tree-ssa/loop-1.c: Make to look like a good unroling candidate still.
	* gcc.dg/tree-ssa/loop-23.c: Likewise.
	* gcc.dg/tree-ssa/cunroll-1.c: Unrolling now happens early.
	* gcc.dg/tree-prof/unroll-1.c: Remove confused dg-options.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@193246 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 33 insertions, 0 deletions

diff --git a/gcc/cfgloopanal.c b/gcc/cfgloopanal.c
index c3cf3edf9b9..ba7c2626635 100644
--- a/gcc/cfgloopanal.c
+++ b/gcc/cfgloopanal.c
@@ -483,3 +483,36 @@ single_likely_exit (struct loop *loop)
   VEC_free (edge, heap, exits);
   return found;
 }
+
+
+/* Gets basic blocks of a LOOP.  Header is the 0-th block, rest is in dfs
+   order against direction of edges from latch.  Specially, if
+   header != latch, latch is the 1-st block.  */
+
+VEC (basic_block, heap) *
+get_loop_hot_path (const struct loop *loop)
+{
+  basic_block bb = loop->header;
+  VEC (basic_block, heap) *path = NULL;
+  bitmap visited = BITMAP_ALLOC (NULL);
+
+  while (true)
+    {
+      edge_iterator ei;
+      edge e;
+      edge best = NULL;
+
+      VEC_safe_push (basic_block, heap, path, bb);
+      bitmap_set_bit (visited, bb->index);
+      FOR_EACH_EDGE (e, ei, bb->succs)
+        if ((!best || e->probability > best->probability)
+	    && !loop_exit_edge_p (loop, e)
+	    && !bitmap_bit_p (visited, e->dest->index))
+	  best = e;
+      if (!best || best->dest == loop->header)
+	break;
+      bb = best->dest;
+    }
+  BITMAP_FREE (visited);
+  return path;
+}