--- a/src/java.base/share/classes/java/lang/invoke/StringConcatFactory.java Tue Apr 16 21:29:33 2019 +0000
+++ b/src/java.base/share/classes/java/lang/invoke/StringConcatFactory.java Wed Apr 17 00:06:38 2019 +0200
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2015, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2019, 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
@@ -26,6 +26,7 @@
package java.lang.invoke;
import jdk.internal.misc.Unsafe;
+import jdk.internal.misc.VM;
import jdk.internal.org.objectweb.asm.ClassWriter;
import jdk.internal.org.objectweb.asm.Label;
import jdk.internal.org.objectweb.asm.MethodVisitor;
@@ -191,6 +192,8 @@
*/
private static final ProxyClassesDumper DUMPER;
+ private static final Class<?> STRING_HELPER;
+
static {
// In case we need to double-back onto the StringConcatFactory during this
// static initialization, make sure we have the reasonable defaults to complete
@@ -202,15 +205,20 @@
// DEBUG = false; // implied
// DUMPER = null; // implied
- Properties props = GetPropertyAction.privilegedGetProperties();
+ try {
+ STRING_HELPER = Class.forName("java.lang.StringConcatHelper");
+ } catch (Throwable e) {
+ throw new AssertionError(e);
+ }
+
final String strategy =
- props.getProperty("java.lang.invoke.stringConcat");
+ VM.getSavedProperty("java.lang.invoke.stringConcat");
CACHE_ENABLE = Boolean.parseBoolean(
- props.getProperty("java.lang.invoke.stringConcat.cache"));
+ VM.getSavedProperty("java.lang.invoke.stringConcat.cache"));
DEBUG = Boolean.parseBoolean(
- props.getProperty("java.lang.invoke.stringConcat.debug"));
+ VM.getSavedProperty("java.lang.invoke.stringConcat.debug"));
final String dumpPath =
- props.getProperty("java.lang.invoke.stringConcat.dumpClasses");
+ VM.getSavedProperty("java.lang.invoke.stringConcat.dumpClasses");
STRATEGY = (strategy == null) ? DEFAULT_STRATEGY : Strategy.valueOf(strategy);
CACHE = CACHE_ENABLE ? new ConcurrentHashMap<>() : null;
@@ -1519,6 +1527,33 @@
static MethodHandle generate(MethodType mt, Recipe recipe) throws Throwable {
+ // Fast-path two-argument Object + Object concatenations
+ if (recipe.getElements().size() == 2) {
+ // Two object arguments
+ if (mt.parameterCount() == 2 &&
+ !mt.parameterType(0).isPrimitive() &&
+ !mt.parameterType(1).isPrimitive()) {
+ return SIMPLE;
+ }
+ // One element is a constant
+ if (mt.parameterCount() == 1 && !mt.parameterType(0).isPrimitive()) {
+ MethodHandle mh = SIMPLE;
+ // Insert constant element
+
+ // First recipe element is a constant
+ if (recipe.getElements().get(0).getTag() == TAG_CONST &&
+ recipe.getElements().get(1).getTag() != TAG_CONST) {
+ return MethodHandles.insertArguments(mh, 0,
+ recipe.getElements().get(0).getValue());
+ } else if (recipe.getElements().get(1).getTag() == TAG_CONST &&
+ recipe.getElements().get(0).getTag() != TAG_CONST) {
+ return MethodHandles.insertArguments(mh, 1,
+ recipe.getElements().get(1).getValue());
+ }
+ // else... fall-through to slow-path
+ }
+ }
+
// Create filters and obtain filtered parameter types. Filters would be used in the beginning
// to convert the incoming arguments into the arguments we can process (e.g. Objects -> Strings).
// The filtered argument type list is used all over in the combinators below.
@@ -1626,13 +1661,6 @@
return mh;
}
- @ForceInline
- private static byte[] newArray(long indexCoder) {
- byte coder = (byte)(indexCoder >> 32);
- int index = (int)indexCoder;
- return (byte[]) UNSAFE.allocateUninitializedArray(byte.class, index << coder);
- }
-
private static MethodHandle prepender(Class<?> cl) {
return PREPENDERS.computeIfAbsent(cl, PREPEND);
}
@@ -1659,16 +1687,15 @@
}
};
+ private static final MethodHandle SIMPLE;
private static final MethodHandle NEW_STRING;
private static final MethodHandle NEW_ARRAY;
private static final ConcurrentMap<Class<?>, MethodHandle> PREPENDERS;
private static final ConcurrentMap<Class<?>, MethodHandle> MIXERS;
private static final long INITIAL_CODER;
- static final Class<?> STRING_HELPER;
static {
try {
- STRING_HELPER = Class.forName("java.lang.StringConcatHelper");
MethodHandle initCoder = lookupStatic(Lookup.IMPL_LOOKUP, STRING_HELPER, "initialCoder", long.class);
INITIAL_CODER = (long) initCoder.invoke();
} catch (Throwable e) {
@@ -1678,8 +1705,9 @@
PREPENDERS = new ConcurrentHashMap<>();
MIXERS = new ConcurrentHashMap<>();
+ SIMPLE = lookupStatic(Lookup.IMPL_LOOKUP, STRING_HELPER, "simpleConcat", String.class, Object.class, Object.class);
NEW_STRING = lookupStatic(Lookup.IMPL_LOOKUP, STRING_HELPER, "newString", String.class, byte[].class, long.class);
- NEW_ARRAY = lookupStatic(Lookup.IMPL_LOOKUP, MethodHandleInlineCopyStrategy.class, "newArray", byte[].class, long.class);
+ NEW_ARRAY = lookupStatic(Lookup.IMPL_LOOKUP, STRING_HELPER, "newArray", byte[].class, long.class);
}
}
@@ -1692,22 +1720,8 @@
// no instantiation
}
- private static class ObjectStringifier {
-
- // We need some additional conversion for Objects in general, because String.valueOf(Object)
- // may return null. String conversion rules in Java state we need to produce "null" String
- // in this case, so we provide a customized version that deals with this problematic corner case.
- private static String valueOf(Object value) {
- String s;
- return (value == null || (s = value.toString()) == null) ? "null" : s;
- }
-
- // Could have used MethodHandles.lookup() instead of Lookup.IMPL_LOOKUP, if not for the fact
- // java.lang.invoke Lookups are explicitly forbidden to be retrieved using that API.
- private static final MethodHandle INSTANCE =
- lookupStatic(Lookup.IMPL_LOOKUP, ObjectStringifier.class, "valueOf", String.class, Object.class);
-
- }
+ private static final MethodHandle OBJECT_INSTANCE =
+ lookupStatic(Lookup.IMPL_LOOKUP, STRING_HELPER, "stringOf", String.class, Object.class);
private static class FloatStringifiers {
private static final MethodHandle FLOAT_INSTANCE =
@@ -1751,7 +1765,7 @@
*/
static MethodHandle forMost(Class<?> t) {
if (!t.isPrimitive()) {
- return ObjectStringifier.INSTANCE;
+ return OBJECT_INSTANCE;
} else if (t == float.class) {
return FloatStringifiers.FLOAT_INSTANCE;
} else if (t == double.class) {