From 7fa2f229fbee68112cbdd18b811d95721adfe2ec Mon Sep 17 00:00:00 2001 From: Maurizio Cimadamore Date: Fri, 4 Oct 2024 09:45:50 +0000 Subject: [PATCH] 8341127: Extra call to MethodHandle::asType from memory segment var handles fails to inline Reviewed-by: psandoz, redestad, jvernee --- .../java/lang/invoke/MethodHandle.java | 16 +- .../foreign/LoopOverNonConstantAsType.java | 138 ++++++++++++++++++ 2 files changed, 152 insertions(+), 2 deletions(-) create mode 100644 test/micro/org/openjdk/bench/java/lang/foreign/LoopOverNonConstantAsType.java diff --git a/src/java.base/share/classes/java/lang/invoke/MethodHandle.java b/src/java.base/share/classes/java/lang/invoke/MethodHandle.java index 104248c27e6..d3270600707 100644 --- a/src/java.base/share/classes/java/lang/invoke/MethodHandle.java +++ b/src/java.base/share/classes/java/lang/invoke/MethodHandle.java @@ -27,6 +27,8 @@ package java.lang.invoke; import jdk.internal.loader.ClassLoaders; +import jdk.internal.vm.annotation.DontInline; +import jdk.internal.vm.annotation.ForceInline; import jdk.internal.vm.annotation.IntrinsicCandidate; import java.lang.constant.ClassDesc; @@ -856,6 +858,7 @@ public abstract sealed class MethodHandle implements Constable * @throws WrongMethodTypeException if the conversion cannot be made * @see MethodHandles#explicitCastArguments */ + @ForceInline public final MethodHandle asType(MethodType newType) { // Fast path alternative to a heavyweight {@code asType} call. // Return 'this' if the conversion will be a no-op. @@ -867,7 +870,7 @@ public abstract sealed class MethodHandle implements Constable if (at != null) { return at; } - return setAsTypeCache(asTypeUncached(newType)); + return setAsTypeCache(newType); } private MethodHandle asTypeCached(MethodType newType) { @@ -885,7 +888,16 @@ public abstract sealed class MethodHandle implements Constable return null; } - private MethodHandle setAsTypeCache(MethodHandle at) { + /* + * We disable inlining here to prevent complex code in the slow path + * of MethodHandle::asType from being inlined into that method. + * Excessive inlining into MethodHandle::asType can cause that method + * to become too big, which will then cause performance issues during + * var handle and method handle calls. + */ + @DontInline + private MethodHandle setAsTypeCache(MethodType newType) { + MethodHandle at = asTypeUncached(newType); // Don't introduce a strong reference in the cache if newType depends on any class loader other than // current method handle already does to avoid class loader leaks. if (isSafeToCache(at.type)) { diff --git a/test/micro/org/openjdk/bench/java/lang/foreign/LoopOverNonConstantAsType.java b/test/micro/org/openjdk/bench/java/lang/foreign/LoopOverNonConstantAsType.java new file mode 100644 index 00000000000..1fbe431b2f2 --- /dev/null +++ b/test/micro/org/openjdk/bench/java/lang/foreign/LoopOverNonConstantAsType.java @@ -0,0 +1,138 @@ +/* + * Copyright (c) 2024, 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. + */ +package org.openjdk.bench.java.lang.foreign; + +import java.lang.foreign.Arena; +import java.lang.foreign.MemorySegment; + +import org.openjdk.jmh.annotations.Benchmark; +import org.openjdk.jmh.annotations.BenchmarkMode; +import org.openjdk.jmh.annotations.CompilerControl; +import org.openjdk.jmh.annotations.Fork; +import org.openjdk.jmh.annotations.Measurement; +import org.openjdk.jmh.annotations.Mode; +import org.openjdk.jmh.annotations.OutputTimeUnit; +import org.openjdk.jmh.annotations.Param; +import org.openjdk.jmh.annotations.Setup; +import org.openjdk.jmh.annotations.State; +import org.openjdk.jmh.annotations.TearDown; +import org.openjdk.jmh.annotations.Warmup; +import sun.misc.Unsafe; + +import java.lang.invoke.MethodHandle; +import java.lang.invoke.MethodHandles; +import java.lang.reflect.Proxy; +import java.net.URL; +import java.net.URLClassLoader; +import java.util.Arrays; +import java.util.concurrent.TimeUnit; + +import static java.lang.foreign.ValueLayout.*; + +@BenchmarkMode(Mode.AverageTime) +@Warmup(iterations = 5, time = 500, timeUnit = TimeUnit.MILLISECONDS) +@Measurement(iterations = 10, time = 500, timeUnit = TimeUnit.MILLISECONDS) +@State(org.openjdk.jmh.annotations.Scope.Thread) +@OutputTimeUnit(TimeUnit.MILLISECONDS) +@Fork(value = 3, jvmArgsAppend = { "-XX:-TieredCompilation" }) +public class LoopOverNonConstantAsType extends JavaLayouts { + + static final Unsafe unsafe = Utils.unsafe; + + static final int ELEM_SIZE = 1_000_000; + static final int CARRIER_SIZE = (int)JAVA_LONG.byteSize(); + static final int ALLOC_SIZE = ELEM_SIZE * CARRIER_SIZE; + + @Param({"false", "true"}) + public boolean asTypeCompiled; + + Arena arena; + MemorySegment segment; + long unsafe_addr; + + @Setup + public void setup() { + unsafe_addr = unsafe.allocateMemory(ALLOC_SIZE); + for (int i = 0; i < ELEM_SIZE; i++) { + unsafe.putInt(unsafe_addr + (i * CARRIER_SIZE) , i); + } + arena = Arena.ofConfined(); + segment = arena.allocate(ALLOC_SIZE, 1); + for (int i = 0; i < ELEM_SIZE; i++) { + VH_INT.set(segment, (long) i, i); + } + if (asTypeCompiled) { + compileAsType(); + } + } + + public interface T { } + + static final int TYPE_SIZE = 100; + static final Class[] types; + + static { + types = new Class[TYPE_SIZE]; + ClassLoader customLoader = new URLClassLoader(new URL[0], LoopOverNonConstantAsType.class.getClassLoader()); + for (int i = 0 ; i < TYPE_SIZE ; i++) { + types[i] = Proxy.newProxyInstance(customLoader, + new Class[] { T.class }, (_, _, _) -> null).getClass(); + } + } + + void compileAsType() { + for (Class type : types) { + MethodHandle handle = MethodHandles.zero(Object.class); + Class[] args = new Class[254]; + Arrays.fill(args, Object.class); + handle = MethodHandles.dropArguments(handle, 0, args); + for (int j = 0; j < args.length ; j++) { + handle = handle.asType(handle.type().changeParameterType(j, type)); + } + } + } + + @TearDown + public void tearDown() { + arena.close(); + unsafe.freeMemory(unsafe_addr); + } + + @Benchmark + public long unsafe_loop() { + long res = 0; + for (int i = 0; i < ELEM_SIZE; i ++) { + res += unsafe.getLong(unsafe_addr + (i * CARRIER_SIZE)); + } + return res; + } + + @Benchmark + public long segment_loop() { + long sum = 0; + for (int i = 0; i < ELEM_SIZE; i++) { + sum += segment.get(JAVA_LONG, i * CARRIER_SIZE); + } + return sum; + } +}