8306997: C2: "malformed control flow" assert due to missing safepoint on backedge with a switch

Reviewed-by: thartmann, kvn
This commit is contained in:
Roland Westrelin 2023-05-03 08:29:01 +00:00
parent 462b1df758
commit e0774bed2d
3 changed files with 106 additions and 2 deletions
src/hotspot/share/opto
test/hotspot/jtreg/compiler/parsing

@ -435,7 +435,7 @@ void Parse::do_tableswitch() {
// generate decision tree, using trichotomy when possible
int rnum = len+2;
bool makes_backward_branch = false;
bool makes_backward_branch = (default_dest <= bci());
SwitchRange* ranges = NEW_RESOURCE_ARRAY(SwitchRange, rnum);
int rp = -1;
if (lo_index != min_jint) {
@ -526,7 +526,7 @@ void Parse::do_lookupswitch() {
}
int rnum = len*2+1;
bool makes_backward_branch = false;
bool makes_backward_branch = (default_dest <= bci());
SwitchRange* ranges = NEW_RESOURCE_ARRAY(SwitchRange, rnum);
int rp = -1;
for (int j = 0; j < len; j++) {

@ -0,0 +1,67 @@
/*
* Copyright (c) 2023, 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.
*/
super public class MissingSafepointOnSwitch
version 52:0
{
public Method "<init>":"()V"
stack 1 locals 1
{
aload_0;
invokespecial Method java/lang/Object."<init>":"()V";
return;
}
/* Same as:
public static void test(boolean flag, int v) {
if (flag) {
loop:
for (; ; ) {
switch(v) {
case 0:
case 1:
case 2:
break loop;
default:
}
}
}
}
but with the default: set to the loop entry
*/
public static Method test:"(ZI)V"
stack 1 locals 2
{
iload_0;
ifeq L32;
L4: stack_frame_type same;
iload_1;
tableswitch{ //0 to 2
0: L32;
1: L32;
2: L32;
default: L4 };
L32: stack_frame_type same;
return;
}
} // end Class TestMissingSafepointOnSwitch

@ -0,0 +1,37 @@
/*
* Copyright (c) 2023, 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 8306997
* @summary C2: "malformed control flow" assert due to missing safepoint on backedge with a switch
* @compile MissingSafepointOnSwitch.jasm
* @run main/othervm -Xcomp -XX:CompileOnly=MissingSafepointOnSwitch::test TestMissingSafepointOnSwitch
*/
public class TestMissingSafepointOnSwitch {
public static void main(String[] args) {
MissingSafepointOnSwitch.test(false, 0);
}
}