# HG changeset patch # User rasbold # Date 1400694899 25200 # Node ID 42d9a5f067283c33633650d368eb88520686894b # Parent 41daa2e6e52d6b2d9d8acd57980b789cc7df15dc 8043354: OptimizePtrCompare too aggressive when allocations are present Summary: In bcEscapeAnalyzer update the _allocated_escapes flag if a var escapes the method. Reviewed-by: kvn diff -r 41daa2e6e52d -r 42d9a5f06728 src/share/vm/ci/bcEscapeAnalyzer.cpp --- a/src/share/vm/ci/bcEscapeAnalyzer.cpp Fri May 30 13:30:07 2014 -0700 +++ b/src/share/vm/ci/bcEscapeAnalyzer.cpp Wed May 21 10:54:59 2014 -0700 @@ -158,6 +158,9 @@ void BCEscapeAnalyzer::set_method_escape(ArgumentMap vars) { clear_bits(vars, _arg_local); + if (vars.contains_allocated()) { + _allocated_escapes = true; + } } void BCEscapeAnalyzer::set_global_escape(ArgumentMap vars, bool merge) { diff -r 41daa2e6e52d -r 42d9a5f06728 test/compiler/EscapeAnalysis/TestAllocatedEscapesPtrComparison.java --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/test/compiler/EscapeAnalysis/TestAllocatedEscapesPtrComparison.java Wed May 21 10:54:59 2014 -0700 @@ -0,0 +1,107 @@ +/* + * Copyright 2014 Google, 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 8043354 + * @summary bcEscapeAnalyzer allocated_escapes not conservative enough + * @run main/othervm -XX:CompileOnly=.visitAndPop TestAllocatedEscapesPtrComparison + * @author Chuck Rasbold rasbold@google.com + */ + +/* + * Test always passes with -XX:-OptmimizePtrCompare + */ + +import java.util.ArrayList; +import java.util.List; + +public class TestAllocatedEscapesPtrComparison { + + static TestAllocatedEscapesPtrComparison dummy; + + class Marker { + } + + List markerList = new ArrayList<>(); + + // Suppress compilation of this method, it must be processed + // by the bytecode escape analyzer. + + // Make a new marker and put it on the List + Marker getMarker() { + // result escapes through markerList + final Marker result = new Marker(); + markerList.add(result); + return result; + } + + void visit(int depth) { + // Make a new marker + getMarker(); + + // Call visitAndPop every once in a while + // Cap the depth of our recursive visits + if (depth % 10 == 2) { + visitAndPop(depth + 1); + } else if (depth < 15) { + visit(depth + 1); + } + } + + void visitAndPop(int depth) { + // Random dummy allocation to force EscapeAnalysis to process this method + dummy = new TestAllocatedEscapesPtrComparison(); + + // Make a new marker + Marker marker = getMarker(); + + visit(depth + 1); + + // Walk and pop the marker list up to the current marker + boolean found = false; + for (int i = markerList.size() - 1; i >= 0; i--) { + Marker removed = markerList.remove(i); + + // In the failure, EA mistakenly converts this comparison to false + if (removed == marker) { + found = true; + break; + } + } + + if (!found) { + throw new RuntimeException("test fails"); + } + } + + + public static void main(String args[]) { + TestAllocatedEscapesPtrComparison tc = new TestAllocatedEscapesPtrComparison(); + + // Warmup and run enough times + for (int i = 0; i < 20000; i++) { + tc.visit(0); + } + } +}