Call compute_outgoing_frequencies at expand

2017-07-17  Tom de Vries  <tom@codesourcery.com>

	PR middle-end/81030
	* cfgbuild.c (find_many_sub_basic_blocks): Add and handle update_freq
	parameter.
	* cfgbuild.h (find_many_sub_basic_blocks): Add update_freq parameter.
	* cfgexpand.c (pass_expand::execute): Call find_many_sub_basic_blocks
	with update_freq == true.

	* gcc.dg/pr81030.c: New test.

---
 gcc/cfgbuild.c                 |  4 ++--
 gcc/cfgbuild.h                 |  3 ++-
 gcc/cfgexpand.c                |  2 +-
 gcc/testsuite/gcc.dg/pr81030.c | 29 +++++++++++++++++++++++++++++
 4 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/gcc/cfgbuild.c b/gcc/cfgbuild.c
index 56a2cb9..78036fe 100644
--- a/gcc/cfgbuild.c
+++ b/gcc/cfgbuild.c
@@ -594,7 +594,7 @@ compute_outgoing_frequencies (basic_block b)
    and create edges.  */
 
 void
-find_many_sub_basic_blocks (sbitmap blocks)
+find_many_sub_basic_blocks (sbitmap blocks, bool update_freq)
 {
   basic_block bb, min, max;
   bool found = false;
@@ -677,7 +677,7 @@ find_many_sub_basic_blocks (sbitmap blocks)
 	  }
 	else
 	  /* If nothing changed, there is no need to create new BBs.  */
-	  if (EDGE_COUNT (bb->succs) == n_succs[bb->index])
+	  if (!update_freq && EDGE_COUNT (bb->succs) == n_succs[bb->index])
 	    continue;
 
 	compute_outgoing_frequencies (bb);
diff --git a/gcc/cfgbuild.h b/gcc/cfgbuild.h
index afda5ac..0c58590 100644
--- a/gcc/cfgbuild.h
+++ b/gcc/cfgbuild.h
@@ -23,6 +23,7 @@ along with GCC; see the file COPYING3.  If not see
 extern bool inside_basic_block_p (const rtx_insn *);
 extern bool control_flow_insn_p (const rtx_insn *);
 extern void rtl_make_eh_edge (sbitmap, basic_block, rtx);
-extern void find_many_sub_basic_blocks (sbitmap);
+extern void find_many_sub_basic_blocks (sbitmap block,
+					bool update_freq = false);
 
 #endif /* GCC_CFGBUILD_H */
diff --git a/gcc/cfgexpand.c b/gcc/cfgexpand.c
index 3e1d24d..e030a86 100644
--- a/gcc/cfgexpand.c
+++ b/gcc/cfgexpand.c
@@ -6464,7 +6464,7 @@ pass_expand::execute (function *fun)
 
   auto_sbitmap blocks (last_basic_block_for_fn (fun));
   bitmap_ones (blocks);
-  find_many_sub_basic_blocks (blocks);
+  find_many_sub_basic_blocks (blocks, true);
   purge_all_dead_edges ();
 
   expand_stack_alignment ();
diff --git a/gcc/testsuite/gcc.dg/pr81030.c b/gcc/testsuite/gcc.dg/pr81030.c
new file mode 100644
index 0000000..23da6e5
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr81030.c
@@ -0,0 +1,29 @@
+/* { dg-do compile } */
+/* { dg-options "-O1" } */
+
+void __assert_fail (const char *, const char *, unsigned int, const char *);
+
+int a, b, c, d, e, f, h;
+unsigned char g;
+
+int main ()
+{
+  int i, *j = &b;
+  if (a)
+    {
+      if (h)
+	{
+	  int **k = &j;
+	  d = 0;
+	  *k = &e;
+	}
+      else
+	for (b = 0; b > -28; b = g)
+	  ;
+      c || !j ? : __assert_fail ("c || !j", "small.c", 20, "main");
+      if (f)
+	for (i = 0; i < 1; i++)
+	  ;
+    }
+  return 0;
+}