* cfgloop.h (DLTHE_FLAG_COMPLETTE_PEEL): New flag.

	* cfgloopmanip.c (duplicate_loop_to_header_edge): Special case
	profile updating for complette unrolling.
	* loop-unroll.c (peel_loop_completely): Use it.
	* tree-ssa-loop-ivcanon.c (try_unroll_loop_completely): Likewise.
	(tree_unroll_loops_completely): Disable code growing unrolling of cold
	loops.

	* update-conroll.c: New testcase.
	* update-conroll-2.c: New testcase.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@102687 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 22 insertions, 1 deletions

diff --git a/gcc/cfgloopmanip.c b/gcc/cfgloopmanip.c
index 648e8372ff8..1e364279403 100644
--- a/gcc/cfgloopmanip.c
+++ b/gcc/cfgloopmanip.c
@@ -913,7 +913,28 @@ duplicate_loop_to_header_edge (struct loop *loop, edge e, struct loops *loops,
 				? prob_pass_wont_exit
 				: prob_pass_thru;
 
-      if (is_latch)
+      /* Complette peeling is special as the probability of exit in last
+         copy becomes 1.  */
+      if (flags & DLTHE_FLAG_COMPLETTE_PEEL)
+	{
+	  int wanted_freq = EDGE_FREQUENCY (e);
+
+	  if (wanted_freq > freq_in)
+	    wanted_freq = freq_in;
+
+	  gcc_assert (!is_latch);
+	  /* First copy has frequency of incomming edge.  Each subseqeuent
+	     frequency should be reduced by prob_pass_wont_exit.  Caller
+	     should've managed the flags so all except for original loop
+	     has won't exist set.  */
+	  scale_act = RDIV (wanted_freq * REG_BR_PROB_BASE, freq_in);
+	  /* Now simulate the duplication adjustments and compute header
+	     frequency of the last copy.  */
+	  for (i = 0; i < ndupl; i++)
+            wanted_freq = RDIV (wanted_freq * scale_step[i], REG_BR_PROB_BASE);
+	  scale_main = RDIV (wanted_freq * REG_BR_PROB_BASE, freq_in);
+	}
+      else if (is_latch)
 	{
 	  prob_pass_main = TEST_BIT (wont_exit, 0)
 				? prob_pass_wont_exit