8078426: mb/jvm/compiler/InterfaceCalls/testAC2 - assert(predicate_proj == 0L) failed: only one predicate entry expected
Summary: split if finds predicates on several incoming paths when unswitched's loops are optimized out
Reviewed-by: kvn
--- a/hotspot/src/share/vm/opto/ifnode.cpp Wed Apr 29 12:23:48 2015 -0700
+++ b/hotspot/src/share/vm/opto/ifnode.cpp Wed Apr 29 14:43:12 2015 -0700
@@ -234,16 +234,24 @@
// Make a region merging constants and a region merging the rest
uint req_c = 0;
Node* predicate_proj = NULL;
+ int nb_predicate_proj = 0;
for (uint ii = 1; ii < r->req(); ii++) {
if (phi->in(ii) == con1) {
req_c++;
}
Node* proj = PhaseIdealLoop::find_predicate(r->in(ii));
if (proj != NULL) {
- assert(predicate_proj == NULL, "only one predicate entry expected");
+ nb_predicate_proj++;
predicate_proj = proj;
}
}
+ if (nb_predicate_proj > 1) {
+ // Can happen in case of loop unswitching and when the loop is
+ // optimized out: it's not a loop anymore so we don't care about
+ // predicates.
+ assert(!r->is_Loop(), "this must not be a loop anymore");
+ predicate_proj = NULL;
+ }
Node* predicate_c = NULL;
Node* predicate_x = NULL;
bool counted_loop = r->is_CountedLoop();
--- a/hotspot/src/share/vm/opto/loopPredicate.cpp Wed Apr 29 12:23:48 2015 -0700
+++ b/hotspot/src/share/vm/opto/loopPredicate.cpp Wed Apr 29 14:43:12 2015 -0700
@@ -89,7 +89,7 @@
//
// We will create a region to guard the uct call if there is no one there.
// The true projecttion (if_cont) of the new_iff is returned.
-// This code is also used to clone predicates to clonned loops.
+// This code is also used to clone predicates to cloned loops.
ProjNode* PhaseIdealLoop::create_new_if_for_predicate(ProjNode* cont_proj, Node* new_entry,
Deoptimization::DeoptReason reason) {
assert(cont_proj->is_uncommon_trap_if_pattern(reason), "must be a uct if pattern!");
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/compiler/loopopts/TestSplitIfUnswitchedLoopsEliminated.java Wed Apr 29 14:43:12 2015 -0700
@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+/**
+ * @test
+ * @bug 8078426
+ * @summary split if finds predicates on several incoming paths when unswitched's loops are optimized out
+ * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:-UseOnStackReplacement -XX:-BackgroundCompilation -XX:-UseCompressedOops TestSplitIfUnswitchedLoopsEliminated
+ *
+ */
+
+
+public class TestSplitIfUnswitchedLoopsEliminated {
+
+ static class A {
+ int f;
+ }
+
+ static A aa = new A();
+ static A aaa = new A();
+
+ static int test_helper(int stop, boolean unswitch) {
+ A a = null;
+ for (int i = 3; i < 10; i++) {
+ if (unswitch) {
+ a = null;
+ } else {
+ a = aa;
+ int v = a.f;
+ }
+ }
+ if (stop != 4) {
+ a = aaa;
+ }
+ if (a != null) {
+ return a.f;
+ }
+ return 0;
+ }
+
+ static int test(boolean unswitch) {
+ int stop = 1;
+ for (; stop < 3; stop *= 4) {
+ }
+ return test_helper(stop, unswitch);
+ }
+
+ public static void main(String[] args) {
+ for (int i = 0; i < 20000; i++) {
+ test_helper(10, i%2 == 0);
+ test(i%2 == 0);
+ }
+ }
+}