8247763: assert(outer->outcnt() == 2) failed: 'only phis' failure in LoopNode::verify_strip_mined()

Reviewed-by: kvn, thartmann

Author: rwestrel

src/hotspot/share/opto/loopopts.cpp

@@ -909,6 +909,9 @@ void PhaseIdealLoop::try_move_store_after_loop(Node* n) {
 
             // Compute latest point this store can go
             Node* lca = get_late_ctrl(n, get_ctrl(n));
+            if (lca->is_OuterStripMinedLoop()) {
+              lca = lca->in(LoopNode::EntryControl);
+            }
             if (n_loop->is_member(get_loop(lca))) {
               // LCA is in the loop - bail out
               _igvn.replace_node(hook, n);

test/hotspot/jtreg/compiler/loopstripmining/TestStoreSunkToOuterLoop.java

@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2020, Red Hat, Inc. 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 8247763
+ * @summary assert(outer->outcnt() == 2) failed: 'only phis' failure in LoopNode::verify_strip_mined()
+ *
+ * @run main/othervm -Xcomp -XX:CompileOnly=TestStoreSunkToOuterLoop TestStoreSunkToOuterLoop
+ *
+ */
+
+public class TestStoreSunkToOuterLoop {
+
+    public static final int N = 400;
+    public static long instanceCount=-62761L;
+    public static boolean bFld=false;
+    public static int iArrFld[]=new int[N];
+
+    public void mainTest() {
+
+        int i15=226, i16=54621, i19=780;
+        float f3=0.671F, f4=-101.846F;
+
+        i15 = 1;
+        do {
+            if (bFld) continue;
+            for (i16 = 1; i16 < 101; ++i16) {
+                iArrFld[i16 - 1] = i15;
+                instanceCount = i16;
+            }
+        } while (++i15 < 248);
+        f3 += -2061721519L;
+        for (f4 = 324; f4 > 3; f4--) {
+            for (i19 = 4; i19 < 78; ++i19) {
+                f3 -= -11;
+            }
+        }
+
+        System.out.println(instanceCount);
+    }
+
+    public static void main(String[] strArr) {
+        TestStoreSunkToOuterLoop _instance = new TestStoreSunkToOuterLoop();
+        for (int i = 0; i < 10; i++ ) {
+            _instance.mainTest();
+        }
+    }
+}