From: jakub <jakub@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Tue, 22 Jan 2019 09:58:23 +0000 (+0000)
Subject: 	PR tree-optimization/88044
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d92b55096267c339f6aab2678c50b31794570a58;p=thirdparty%2Fgcc.git

	PR tree-optimization/88044
	* tree-ssa-loop-niter.c (number_of_iterations_cond): If condition
	is false in the first iteration, but !every_iteration, return false
	instead of true with niter->niter zero.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@268143 138bc75d-0d04-0410-961f-82ee72b054a4
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 64f920ece339..feda772ffc6d 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,10 @@
 2019-01-22  Jakub Jelinek  <jakub@redhat.com>
 
+	PR tree-optimization/88044
+	* tree-ssa-loop-niter.c (number_of_iterations_cond): If condition
+	is false in the first iteration, but !every_iteration, return false
+	instead of true with niter->niter zero.
+
 	PR rtl-optimization/88904
 	* cfgcleanup.c (thread_jump): Verify cond2 doesn't mention
 	any nonequal registers before processing BB_END (b).
diff --git a/gcc/tree-ssa-loop-niter.c b/gcc/tree-ssa-loop-niter.c
index 622d18abacb5..470b6a295be5 100644
--- a/gcc/tree-ssa-loop-niter.c
+++ b/gcc/tree-ssa-loop-niter.c
@@ -1824,6 +1824,8 @@ number_of_iterations_cond (struct loop *loop,
   tree tem = fold_binary (code, boolean_type_node, iv0->base, iv1->base);
   if (tem && integer_zerop (tem))
     {
+      if (!every_iteration)
+	return false;
       niter->niter = build_int_cst (unsigned_type_for (type), 0);
       niter->max = 0;
       return true;