From d58ebe4882c0dfcb2f185e948c5c838f2d867e6b Mon Sep 17 00:00:00 2001
Date: Wed, 12 Jun 2019 20:43:23 +0000
Subject: [PATCH] fix-fastdebug-jdk-crash-when-running-a-jtreg-case
 
Summary: The problem happens when c1’s loop optimizations encounter a non natural loop for which one entry is an exception handler.Backport the patch from openjdk9
LLT:
Bug url: https://bugs.openjdk.java.net/browse/JDK-8134883

---
 hotspot/src/share/vm/c1/c1_IR.cpp             |  7 +-
 .../TestRangeCheckExceptionHandlerLoop.jasm   | 89 +++++++++++++++++++
 ...estRangeCheckExceptionHandlerLoopMain.java | 41 +++++++++
 3 files changed, 134 insertions(+), 3 deletions(-)
 create mode 100644 hotspot/test/compiler/rangechecks/TestRangeCheckExceptionHandlerLoop.jasm
 create mode 100644 hotspot/test/compiler/rangechecks/TestRangeCheckExceptionHandlerLoopMain.java

diff --git a/hotspot/src/share/vm/c1/c1_IR.cpp b/hotspot/src/share/vm/c1/c1_IR.cpp
index 0984098764..b500d5cf79 100644
--- a/hotspot/src/share/vm/c1/c1_IR.cpp
+++ b/hotspot/src/share/vm/c1/c1_IR.cpp
@@ -578,11 +578,8 @@ void ComputeLinearScanOrder::count_edges(BlockBegin* cur, BlockBegin* parent) {
     assert(is_visited(cur), "block must be visisted when block is active");
     assert(parent != NULL, "must have parent");
 
-    cur->set(BlockBegin::linear_scan_loop_header_flag);
     cur->set(BlockBegin::backward_branch_target_flag);
 
-    parent->set(BlockBegin::linear_scan_loop_end_flag);
-
     // When a loop header is also the start of an exception handler, then the backward branch is
     // an exception edge. Because such edges are usually critical edges which cannot be split, the
     // loop must be excluded here from processing.
@@ -591,6 +588,10 @@ void ComputeLinearScanOrder::count_edges(BlockBegin* cur, BlockBegin* parent) {
       _iterative_dominators = true;
       return;
     }
+
+    cur->set(BlockBegin::linear_scan_loop_header_flag);
+    parent->set(BlockBegin::linear_scan_loop_end_flag);
+
     assert(parent->number_of_sux() == 1 && parent->sux_at(0) == cur,
            "loop end blocks must have one successor (critical edges are split)");
 
diff --git a/hotspot/test/compiler/rangechecks/TestRangeCheckExceptionHandlerLoop.jasm b/hotspot/test/compiler/rangechecks/TestRangeCheckExceptionHandlerLoop.jasm
new file mode 100644
index 0000000000..2befe6db09
--- /dev/null
+++ b/hotspot/test/compiler/rangechecks/TestRangeCheckExceptionHandlerLoop.jasm
@@ -0,0 +1,89 @@
+/*
+ * 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.
+ *
+ */
+
+super public class TestRangeCheckExceptionHandlerLoop
+	version 51:0
+{
+
+
+public Method "<init>":"()V"
+	stack 1 locals 1
+{
+		aload_0;
+		invokespecial	Method java/lang/Object."<init>":"()V";
+		return;
+}
+
+/* This method has an irreducible loop, with 2 entries, one is the exception handler
+
+    static void test(boolean flag, int[] array, Exception exception) throws Exception {
+        int i = 0;
+        if (flag) {
+            try {
+                throw exception;
+            } catch(Exception e) {
+                array[i] = 0;
+                i++;
+            }
+        }
+        if (i < 10) {
+            throw exception; // caught by exception handler above as well
+        }
+    }
+*/
+public static Method test:"(Z[ILjava/lang/Exception;)V"
+	throws java/lang/Exception
+	stack 3 locals 5
+{
+		iconst_0;
+		istore_3;
+		iload_0;
+		ifeq	L17;
+		try t0;
+		aload_2;
+		athrow;
+		endtry t0;
+		catch t0 java/lang/Exception;
+		catch t1 java/lang/Exception;
+		stack_frame_type full;
+		locals_map int, class "[I", class java/lang/Exception, int;
+		stack_map class java/lang/Exception;
+		astore	4;
+		aload_1;
+		iload_3;
+		iconst_0;
+		iastore;
+		iinc	3, 1;
+	L17:	stack_frame_type same;
+		iload_3;
+		bipush	10;
+		if_icmpge	L25;
+		try t1;
+		aload_2;
+		athrow;
+		endtry t1;
+	L25:	stack_frame_type same;
+		return;
+}
+} // end Class TestRangeCheckExceptionHandlerLoop
diff --git a/hotspot/test/compiler/rangechecks/TestRangeCheckExceptionHandlerLoopMain.java b/hotspot/test/compiler/rangechecks/TestRangeCheckExceptionHandlerLoopMain.java
new file mode 100644
index 0000000000..32df890bc0
--- /dev/null
+++ b/hotspot/test/compiler/rangechecks/TestRangeCheckExceptionHandlerLoopMain.java
@@ -0,0 +1,41 @@
+/*
+ * 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 8134883
+ * @summary C1's range check elimination breaks with a non-natural loop that an exception handler as one entry
+ * @compile TestRangeCheckExceptionHandlerLoop.jasm
+ * @run main/othervm -XX:-BackgroundCompilation -XX:-UseOnStackReplacement TestRangeCheckExceptionHandlerLoopMain
+ */
+
+public class TestRangeCheckExceptionHandlerLoopMain {
+    public static void main(String[] args) throws Exception {
+        Exception exception = new Exception();
+        int[] array = new int[10];
+        for (int i = 0; i < 20000; i++) {
+            TestRangeCheckExceptionHandlerLoop.test(false, array, exception);
+        }
+    }
+}
-- 
2.19.0