[PATCH GCC][02/13]Skip distribution if there is no loop

[Bin Cheng]

Hi,
this is a simple patch skipping distribution if there is no loop at all.

Bootstrap and test on x86_64 and AArch64.  Is it OK?

Thanks,
bin

2017-06-07  Bin Cheng  <bin.ch...@arm.com>

        * cfgloop.h (pass_loop_distribution::execute): Skip if no loops.
From eb6a795331efde92fd6df1c6e612fb1ffa9f482f Mon Sep 17 00:00:00 2001
From: Bin Cheng <binch...@e108451-lin.cambridge.arm.com>
Date: Fri, 9 Jun 2017 09:30:40 +0100
Subject: [PATCH 02/14] fast-return-20170607.txt

---
 gcc/tree-loop-distribution.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/gcc/tree-loop-distribution.c b/gcc/tree-loop-distribution.c
index a60454b..9f0c801 100644
--- a/gcc/tree-loop-distribution.c
+++ b/gcc/tree-loop-distribution.c
@@ -1758,6 +1758,9 @@ pass_loop_distribution::execute (function *fun)
   control_dependences *cd = NULL;
   auto_vec<loop_p> loops_to_be_destroyed;
 
+  if (number_of_loops (fun) <= 1)
+    return 0;
+
   FOR_ALL_BB_FN (bb, fun)
     {
       gimple_stmt_iterator gsi;
-- 
1.9.1