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A maven release for nashorn. Changed nothing, just put it to maven.
/*
* Copyright (c) 2010, 2014, 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. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* 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 jdk.nashorn.internal.codegen;
import static jdk.nashorn.internal.codegen.CompilerConstants.ARGUMENTS_VAR;
import static jdk.nashorn.internal.codegen.CompilerConstants.EXPLODED_ARGUMENT_PREFIX;
import java.lang.invoke.MethodType;
import java.net.URL;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Deque;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import jdk.nashorn.internal.ir.AccessNode;
import jdk.nashorn.internal.ir.CallNode;
import jdk.nashorn.internal.ir.Expression;
import jdk.nashorn.internal.ir.FunctionNode;
import jdk.nashorn.internal.ir.IdentNode;
import jdk.nashorn.internal.ir.Node;
import jdk.nashorn.internal.ir.visitor.SimpleNodeVisitor;
import jdk.nashorn.internal.objects.Global;
import jdk.nashorn.internal.runtime.Context;
import jdk.nashorn.internal.runtime.logging.DebugLogger;
import jdk.nashorn.internal.runtime.logging.Loggable;
import jdk.nashorn.internal.runtime.logging.Logger;
import jdk.nashorn.internal.runtime.options.Options;
/**
* An optimization that attempts to turn applies into calls. This pattern
* is very common for fake class instance creation, and apply
* introduces expensive args collection and boxing
*
*
* var Class = {
* create: function() {
* return function() { //vararg
* this.initialize.apply(this, arguments);
* }
* }
* };
*
* Color = Class.create();
*
* Color.prototype = {
* red: 0, green: 0, blue: 0,
* initialize: function(r,g,b) {
* this.red = r;
* this.green = g;
* this.blue = b;
* }
* }
*
* new Color(17, 47, 11);
*
*/
@Logger(name="apply2call")
public final class ApplySpecialization extends SimpleNodeVisitor implements Loggable {
private static final boolean USE_APPLY2CALL = Options.getBooleanProperty("nashorn.apply2call", true);
private final DebugLogger log;
private final Compiler compiler;
private final Set changed = new HashSet<>();
private final Deque> explodedArguments = new ArrayDeque<>();
private final Deque callSiteTypes = new ArrayDeque<>();
private static final String ARGUMENTS = ARGUMENTS_VAR.symbolName();
/**
* Apply specialization optimization. Try to explode arguments and call
* applies as calls if they just pass on the "arguments" array and
* "arguments" doesn't escape.
*
* @param compiler compiler
*/
public ApplySpecialization(final Compiler compiler) {
this.compiler = compiler;
this.log = initLogger(compiler.getContext());
}
@Override
public DebugLogger getLogger() {
return log;
}
@Override
public DebugLogger initLogger(final Context context) {
return context.getLogger(this.getClass());
}
@SuppressWarnings("serial")
private static class TransformFailedException extends RuntimeException {
TransformFailedException(final FunctionNode fn, final String message) {
super(massageURL(fn.getSource().getURL()) + '.' + fn.getName() + " => " + message, null, false, false);
}
}
@SuppressWarnings("serial")
private static class AppliesFoundException extends RuntimeException {
AppliesFoundException() {
super("applies_found", null, false, false);
}
}
private static final AppliesFoundException HAS_APPLIES = new AppliesFoundException();
private boolean hasApplies(final FunctionNode functionNode) {
try {
functionNode.accept(new SimpleNodeVisitor() {
@Override
public boolean enterFunctionNode(final FunctionNode fn) {
return fn == functionNode;
}
@Override
public boolean enterCallNode(final CallNode callNode) {
if (isApply(callNode)) {
throw HAS_APPLIES;
}
return true;
}
});
} catch (final AppliesFoundException e) {
return true;
}
log.fine("There are no applies in ", DebugLogger.quote(functionNode.getName()), " - nothing to do.");
return false; // no applies
}
/**
* Arguments may only be used as args to the apply. Everything else is disqualified
* We cannot control arguments if they escape from the method and go into an unknown
* scope, thus we are conservative and treat any access to arguments outside the
* apply call as a case of "we cannot apply the optimization".
*/
private static void checkValidTransform(final FunctionNode functionNode) {
final Set argumentsFound = new HashSet<>();
final Deque> stack = new ArrayDeque<>();
//ensure that arguments is only passed as arg to apply
functionNode.accept(new SimpleNodeVisitor() {
private boolean isCurrentArg(final Expression expr) {
return !stack.isEmpty() && stack.peek().contains(expr); //args to current apply call
}
private boolean isArguments(final Expression expr) {
if (expr instanceof IdentNode && ARGUMENTS.equals(((IdentNode)expr).getName())) {
argumentsFound.add(expr);
return true;
}
return false;
}
private boolean isParam(final String name) {
for (final IdentNode param : functionNode.getParameters()) {
if (param.getName().equals(name)) {
return true;
}
}
return false;
}
@Override
public Node leaveIdentNode(final IdentNode identNode) {
if (isParam(identNode.getName())) {
throw new TransformFailedException(lc.getCurrentFunction(), "parameter: " + identNode.getName());
}
// it's OK if 'argument' occurs as the current argument of an apply
if (isArguments(identNode) && !isCurrentArg(identNode)) {
throw new TransformFailedException(lc.getCurrentFunction(), "is 'arguments': " + identNode.getName());
}
return identNode;
}
@Override
public boolean enterCallNode(final CallNode callNode) {
final Set callArgs = new HashSet<>();
if (isApply(callNode)) {
final List argList = callNode.getArgs();
if (argList.size() != 2 || !isArguments(argList.get(argList.size() - 1))) {
throw new TransformFailedException(lc.getCurrentFunction(), "argument pattern not matched: " + argList);
}
callArgs.addAll(callNode.getArgs());
}
stack.push(callArgs);
return true;
}
@Override
public Node leaveCallNode(final CallNode callNode) {
stack.pop();
return callNode;
}
});
}
@Override
public boolean enterCallNode(final CallNode callNode) {
return !explodedArguments.isEmpty();
}
@Override
public Node leaveCallNode(final CallNode callNode) {
//apply needs to be a global symbol or we don't allow it
final List newParams = explodedArguments.peek();
if (isApply(callNode)) {
final List newArgs = new ArrayList<>();
for (final Expression arg : callNode.getArgs()) {
if (arg instanceof IdentNode && ARGUMENTS.equals(((IdentNode)arg).getName())) {
newArgs.addAll(newParams);
} else {
newArgs.add(arg);
}
}
changed.add(lc.getCurrentFunction().getId());
final CallNode newCallNode = callNode.setArgs(newArgs).setIsApplyToCall();
if (log.isEnabled()) {
log.fine("Transformed ",
callNode,
" from apply to call => ",
newCallNode,
" in ",
DebugLogger.quote(lc.getCurrentFunction().getName()));
}
return newCallNode;
}
return callNode;
}
private void pushExplodedArgs(final FunctionNode functionNode) {
int start = 0;
final MethodType actualCallSiteType = compiler.getCallSiteType(functionNode);
if (actualCallSiteType == null) {
throw new TransformFailedException(lc.getCurrentFunction(), "No callsite type");
}
assert actualCallSiteType.parameterType(actualCallSiteType.parameterCount() - 1) != Object[].class : "error vararg callsite passed to apply2call " + functionNode.getName() + " " + actualCallSiteType;
final TypeMap ptm = compiler.getTypeMap();
if (ptm.needsCallee()) {
start++;
}
start++; // we always use this
assert functionNode.getNumOfParams() == 0 : "apply2call on function with named paramaters!";
final List newParams = new ArrayList<>();
final long to = actualCallSiteType.parameterCount() - start;
for (int i = 0; i < to; i++) {
newParams.add(new IdentNode(functionNode.getToken(), functionNode.getFinish(), EXPLODED_ARGUMENT_PREFIX.symbolName() + (i)));
}
callSiteTypes.push(actualCallSiteType);
explodedArguments.push(newParams);
}
@Override
public boolean enterFunctionNode(final FunctionNode functionNode) {
// Cheap tests first
if (!(
// is the transform globally enabled?
USE_APPLY2CALL
// Are we compiling lazily? We can't known the number and types of the actual parameters at
// the caller when compiling eagerly, so this only works with on-demand compilation.
&& compiler.isOnDemandCompilation()
// Does the function even reference the "arguments" identifier (without redefining it)? If not,
// it trivially can't have an expression of form "f.apply(self, arguments)" that this transform
// is targeting.
&& functionNode.needsArguments()
// Does the function have eval? If so, it can arbitrarily modify arguments so we can't touch it.
&& !functionNode.hasEval()
// Finally, does the function declare any parameters explicitly? We don't support that. It could
// be done, but has some complications. Therefore only a function with no explicit parameters
// is considered.
&& functionNode.getNumOfParams() == 0))
{
return false;
}
if (!Global.isBuiltinFunctionPrototypeApply()) {
log.fine("Apply transform disabled: apply/call overridden");
assert !Global.isBuiltinFunctionPrototypeCall() : "call and apply should have the same SwitchPoint";
return false;
}
if (!hasApplies(functionNode)) {
return false;
}
if (log.isEnabled()) {
log.info("Trying to specialize apply to call in '",
functionNode.getName(),
"' params=",
functionNode.getParameters(),
" id=",
functionNode.getId(),
" source=",
massageURL(functionNode.getSource().getURL()));
}
try {
checkValidTransform(functionNode);
pushExplodedArgs(functionNode);
} catch (final TransformFailedException e) {
log.info("Failure: ", e.getMessage());
return false;
}
return true;
}
/**
* Try to do the apply to call transformation
* @return true if successful, false otherwise
*/
@Override
public Node leaveFunctionNode(final FunctionNode functionNode) {
FunctionNode newFunctionNode = functionNode;
final String functionName = newFunctionNode.getName();
if (changed.contains(newFunctionNode.getId())) {
newFunctionNode = newFunctionNode.clearFlag(lc, FunctionNode.USES_ARGUMENTS).
setFlag(lc, FunctionNode.HAS_APPLY_TO_CALL_SPECIALIZATION).
setParameters(lc, explodedArguments.peek());
if (log.isEnabled()) {
log.info("Success: ",
massageURL(newFunctionNode.getSource().getURL()),
'.',
functionName,
"' id=",
newFunctionNode.getId(),
" params=",
callSiteTypes.peek());
}
}
callSiteTypes.pop();
explodedArguments.pop();
return newFunctionNode;
}
private static boolean isApply(final CallNode callNode) {
final Expression f = callNode.getFunction();
return f instanceof AccessNode && "apply".equals(((AccessNode)f).getProperty());
}
private static String massageURL(final URL url) {
if (url == null) {
return "";
}
final String str = url.toString();
final int slash = str.lastIndexOf('/');
if (slash == -1) {
return str;
}
return str.substring(slash + 1);
}
}