infernap12/jdk
1
0
Fork 0
mirror of https://github.com/openjdk/jdk.git synced 2026-04-05 04:31:36 +00:00
Code Issues Packages Projects Releases Wiki Activity

Merge

Browse Source
This commit is contained in:
Jesper Wilhelmsson 2017-03-20 23:49:33 +01:00
commit 65d9c94add
2 changed files with 79 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
hotspot/src/share/vm/opto/lcm.cpp
View File

@ -254,10 +254,12 @@ void PhaseCFG::implicit_null_check(Block* block, Node *proj, Node *val, int allo
const TypePtr *adr_type = NULL; // Do not need this return value here
const Node* base = mach->get_base_and_disp(offset, adr_type);
if (base == NULL || base == NodeSentinel) {
// Narrow oop address doesn't have base, only index
if( val->bottom_type()->isa_narrowoop() &&
MacroAssembler::needs_explicit_null_check(offset) )
continue; // Give up if offset is beyond page size
// Narrow oop address doesn't have base, only index.
// Give up if offset is beyond page size or if heap base is not protected.
if (val->bottom_type()->isa_narrowoop() &&
(MacroAssembler::needs_explicit_null_check(offset) ||
!Universe::narrow_oop_use_implicit_null_checks()))
continue;
// cannot reason about it; is probably not implicit null exception
} else {
const TypePtr* tptr;
@ -269,12 +271,17 @@ void PhaseCFG::implicit_null_check(Block* block, Node *proj, Node *val, int allo
// only regular oops are expected here
tptr = base->bottom_type()->is_ptr();
}
// Give up if offset is not a compile-time constant
if( offset == Type::OffsetBot || tptr->_offset == Type::OffsetBot )
// Give up if offset is not a compile-time constant.
if (offset == Type::OffsetBot || tptr->_offset == Type::OffsetBot)
continue;
offset += tptr->_offset; // correct if base is offseted
if( MacroAssembler::needs_explicit_null_check(offset) )
continue; // Give up is reference is beyond 4K page size
// Give up if reference is beyond page size.
if (MacroAssembler::needs_explicit_null_check(offset))
continue;
// Give up if base is a decode node and the heap base is not protected.
if (base->is_Mach() && base->as_Mach()->ideal_Opcode() == Op_DecodeN &&
!Universe::narrow_oop_use_implicit_null_checks())
continue;
}
}

64
hotspot/test/compiler/c2/TestNPEHeapBased.java Normal file
View File

@ -0,0 +1,64 @@
/*
* Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2017 SAP SE. 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 8176518
* @summary Invalid ImplicitNullChecks when heap base not protected
*
* @run main/othervm -XX:ObjectAlignmentInBytes=16 -XX:HeapBaseMinAddress=64g
* -XX:-TieredCompilation -Xbatch
* compiler.c2.TestNPEHeapBased
* @requires vm.bits == "64"
*/
package compiler.c2;
public class TestNPEHeapBased {
TestNPEHeapBased instance = null;
int i = 0;
public void set_i(int value) {
instance.i = value;
}
static final int loop_cnt = 200000;
public static void main(String args[]){
TestNPEHeapBased xyz = new TestNPEHeapBased();
xyz.instance = xyz;
for (int x = 0; x < loop_cnt; x++) xyz.set_i(x);
xyz.instance = null;
try {
xyz.set_i(0);
} catch (NullPointerException npe) {
System.out.println("Got expected NullPointerException:");
npe.printStackTrace();
return;
}
throw new InternalError("NullPointerException is missing!");
}
}