/*
* 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.runtime;
import static jdk.nashorn.internal.lookup.Lookup.MH;
import java.io.IOException;
import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;
import java.lang.ref.Reference;
import java.lang.ref.SoftReference;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.IdentityHashMap;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.LinkedBlockingDeque;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import jdk.nashorn.internal.codegen.Compiler;
import jdk.nashorn.internal.codegen.Compiler.CompilationPhases;
import jdk.nashorn.internal.codegen.CompilerConstants;
import jdk.nashorn.internal.codegen.FunctionSignature;
import jdk.nashorn.internal.codegen.Namespace;
import jdk.nashorn.internal.codegen.OptimisticTypesPersistence;
import jdk.nashorn.internal.codegen.TypeMap;
import jdk.nashorn.internal.codegen.types.Type;
import jdk.nashorn.internal.ir.Block;
import jdk.nashorn.internal.ir.ForNode;
import jdk.nashorn.internal.ir.FunctionNode;
import jdk.nashorn.internal.ir.IdentNode;
import jdk.nashorn.internal.ir.LexicalContext;
import jdk.nashorn.internal.ir.Node;
import jdk.nashorn.internal.ir.SwitchNode;
import jdk.nashorn.internal.ir.Symbol;
import jdk.nashorn.internal.ir.TryNode;
import jdk.nashorn.internal.ir.visitor.SimpleNodeVisitor;
import jdk.nashorn.internal.objects.Global;
import jdk.nashorn.internal.parser.Parser;
import jdk.nashorn.internal.parser.Token;
import jdk.nashorn.internal.parser.TokenType;
import jdk.nashorn.internal.runtime.linker.NameCodec;
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;
/**
* This is a subclass that represents a script function that may be regenerated,
* for example with specialization based on call site types, or lazily generated.
* The common denominator is that it can get new invokers during its lifespan,
* unlike {@code FinalScriptFunctionData}
*/
@Logger(name="recompile")
public final class RecompilableScriptFunctionData extends ScriptFunctionData implements Loggable {
/** Prefix used for all recompiled script classes */
public static final String RECOMPILATION_PREFIX = "Recompilation$";
private static final ExecutorService astSerializerExecutorService = createAstSerializerExecutorService();
/** Unique function node id for this function node */
private final int functionNodeId;
private final String functionName;
/** The line number where this function begins. */
private final int lineNumber;
/** Source from which FunctionNode was parsed. */
private transient Source source;
/**
* Cached form of the AST. Either a {@code SerializedAst} object used by split functions as they can't be
* reparsed from source, or a soft reference to a {@code FunctionNode} for other functions (it is safe
* to be cleared as they can be reparsed).
*/
private volatile Object cachedAst;
/** Token of this function within the source. */
private final long token;
/**
* Represents the allocation strategy (property map, script object class, and method handle) for when
* this function is used as a constructor. Note that majority of functions (those not setting any this.*
* properties) will share a single canonical "default strategy" instance.
*/
private final AllocationStrategy allocationStrategy;
/**
* Opaque object representing parser state at the end of the function. Used when reparsing outer function
* to help with skipping parsing inner functions.
*/
private final Object endParserState;
/** Code installer used for all further recompilation/specialization of this ScriptFunction */
private transient CodeInstaller installer;
private final Map<Integer, RecompilableScriptFunctionData> nestedFunctions;
/** Id to parent function if one exists */
private RecompilableScriptFunctionData parent;
/** Copy of the {@link FunctionNode} flags. */
private final int functionFlags;
private static final MethodHandles.Lookup LOOKUP = MethodHandles.lookup();
private transient DebugLogger log;
private final Map<String, Integer> externalScopeDepths;
private final Set<String> internalSymbols;
private static final int GET_SET_PREFIX_LENGTH = "*et ".length();
private static final long serialVersionUID = 4914839316174633726L;
/**
* Constructor - public as scripts use it
*
* @param functionNode functionNode that represents this function code
* @param installer installer for code regeneration versions of this function
* @param allocationStrategy strategy for the allocation behavior when this function is used as a constructor
* @param nestedFunctions nested function map
* @param externalScopeDepths external scope depths
* @param internalSymbols internal symbols to method, defined in its scope
*/
public RecompilableScriptFunctionData(
final FunctionNode functionNode,
final CodeInstaller installer,
final AllocationStrategy allocationStrategy,
final Map<Integer, RecompilableScriptFunctionData> nestedFunctions,
final Map<String, Integer> externalScopeDepths,
final Set<String> internalSymbols) {
super(functionName(functionNode),
Math.min(functionNode.getParameters().size(), MAX_ARITY),
getDataFlags(functionNode));
this.functionName = functionNode.getName();
this.lineNumber = functionNode.getLineNumber();
this.functionFlags = functionNode.getFlags() | (functionNode.needsCallee() ? FunctionNode.NEEDS_CALLEE : 0);
this.functionNodeId = functionNode.getId();
this.source = functionNode.getSource();
this.endParserState = functionNode.getEndParserState();
this.token = tokenFor(functionNode);
this.installer = installer;
this.allocationStrategy = allocationStrategy;
this.nestedFunctions = smallMap(nestedFunctions);
this.externalScopeDepths = smallMap(externalScopeDepths);
this.internalSymbols = smallSet(new HashSet<>(internalSymbols));
for (final RecompilableScriptFunctionData nfn : nestedFunctions.values()) {
assert nfn.getParent() == null;
nfn.setParent(this);
}
createLogger();
}
private static <K, V> Map<K, V> smallMap(final Map<K, V> map) {
if (map == null || map.isEmpty()) {
return Collections.emptyMap();
} else if (map.size() == 1) {
final Map.Entry<K, V> entry = map.entrySet().iterator().next();
return Collections.singletonMap(entry.getKey(), entry.getValue());
} else {
return map;
}
}
private static <T> Set<T> smallSet(final Set<T> set) {
if (set == null || set.isEmpty()) {
return Collections.emptySet();
} else if (set.size() == 1) {
return Collections.singleton(set.iterator().next());
} else {
return set;
}
}
@Override
public DebugLogger getLogger() {
return log;
}
@Override
public DebugLogger initLogger(final Context ctxt) {
return ctxt.getLogger(this.getClass());
}
/**
* Check if a symbol is internally defined in a function. For example
* if "undefined" is internally defined in the outermost program function,
* it has not been reassigned or overridden and can be optimized
*
* @param symbolName symbol name
* @return true if symbol is internal to this ScriptFunction
*/
public boolean hasInternalSymbol(final String symbolName) {
return internalSymbols.contains(symbolName);
}
/**
* Return the external symbol table
* @param symbolName symbol name
* @return the external symbol table with proto depths
*/
public int getExternalSymbolDepth(final String symbolName) {
final Integer depth = externalScopeDepths.get(symbolName);
return depth == null ? -1 : depth;
}
/**
* Returns the names of all external symbols this function uses.
* @return the names of all external symbols this function uses.
*/
public Set<String> getExternalSymbolNames() {
return Collections.unmodifiableSet(externalScopeDepths.keySet());
}
/**
* Returns the opaque object representing the parser state at the end of this function's body, used to
* skip parsing this function when reparsing its containing outer function.
* @return the object representing the end parser state
*/
public Object getEndParserState() {
return endParserState;
}
/**
* Get the parent of this RecompilableScriptFunctionData. If we are
* a nested function, we have a parent. Note that "null" return value
* can also mean that we have a parent but it is unknown, so this can
* only be used for conservative assumptions.
* @return parent data, or null if non exists and also null IF UNKNOWN.
*/
public RecompilableScriptFunctionData getParent() {
return parent;
}
void setParent(final RecompilableScriptFunctionData parent) {
this.parent = parent;
}
@Override
String toSource() {
if (source != null && token != 0) {
return source.getString(Token.descPosition(token), Token.descLength(token));
}
return "function " + (name == null ? "" : name) + "() { [native code] }";
}
/**
* Initialize transient fields on deserialized instances
*
* @param src source
* @param inst code installer
*/
public void initTransients(final Source src, final CodeInstaller inst) {
if (this.source == null && this.installer == null) {
this.source = src;
this.installer = inst;
} else if (this.source != src || !this.installer.isCompatibleWith(inst)) {
// Existing values must be same as those passed as parameters
throw new IllegalArgumentException();
}
}
@Override
public String toString() {
return super.toString() + '@' + functionNodeId;
}
@Override
public String toStringVerbose() {
final StringBuilder sb = new StringBuilder();
sb.append("fnId=").append(functionNodeId).append(' ');
if (source != null) {
sb.append(source.getName())
.append(':')
.append(lineNumber)
.append(' ');
}
return sb.toString() + super.toString();
}
@Override
public String getFunctionName() {
return functionName;
}
@Override
public boolean inDynamicContext() {
return getFunctionFlag(FunctionNode.IN_DYNAMIC_CONTEXT);
}
private static String functionName(final FunctionNode fn) {
if (fn.isAnonymous()) {
return "";
}
final FunctionNode.Kind kind = fn.getKind();
if (kind == FunctionNode.Kind.GETTER || kind == FunctionNode.Kind.SETTER) {
final String name = NameCodec.decode(fn.getIdent().getName());
return name.substring(GET_SET_PREFIX_LENGTH);
}
return fn.getIdent().getName();
}
private static long tokenFor(final FunctionNode fn) {
final int position = Token.descPosition(fn.getFirstToken());
final long lastToken = Token.withDelimiter(fn.getLastToken());
// EOL uses length field to store the line number
final int length = Token.descPosition(lastToken) - position + (Token.descType(lastToken) == TokenType.EOL ? 0 : Token.descLength(lastToken));
return Token.toDesc(TokenType.FUNCTION, position, length);
}
private static int getDataFlags(final FunctionNode functionNode) {
int flags = IS_CONSTRUCTOR;
if (functionNode.isStrict()) {
flags |= IS_STRICT;
}
if (functionNode.needsCallee()) {
flags |= NEEDS_CALLEE;
}
if (functionNode.usesThis() || functionNode.hasEval()) {
flags |= USES_THIS;
}
if (functionNode.isVarArg()) {
flags |= IS_VARIABLE_ARITY;
}
if (functionNode.getKind() == FunctionNode.Kind.GETTER || functionNode.getKind() == FunctionNode.Kind.SETTER) {
flags |= IS_PROPERTY_ACCESSOR;
}
if (functionNode.isMethod() || functionNode.isClassConstructor()) {
flags |= IS_ES6_METHOD;
}
return flags;
}
@Override
PropertyMap getAllocatorMap(final ScriptObject prototype) {
return allocationStrategy.getAllocatorMap(prototype);
}
@Override
ScriptObject allocate(final PropertyMap map) {
return allocationStrategy.allocate(map);
}
FunctionNode reparse() {
final FunctionNode cachedFunction = getCachedAst();
if (cachedFunction != null) {
assert cachedFunction.isCached();
return cachedFunction;
}
final int descPosition = Token.descPosition(token);
final Context context = Context.getContextTrusted();
final Parser parser = new Parser(
context.getEnv(),
source,
new Context.ThrowErrorManager(),
isStrict(),
// source starts at line 0, so even though lineNumber is the correct declaration line, back off
// one to make it exclusive
lineNumber - 1,
context.getLogger(Parser.class));
if (getFunctionFlag(FunctionNode.IS_ANONYMOUS)) {
parser.setFunctionName(functionName);
}
parser.setReparsedFunction(this);
final FunctionNode program = parser.parse(CompilerConstants.PROGRAM.symbolName(), descPosition,
Token.descLength(token), flags);
// Parser generates a program AST even if we're recompiling a single function, so when we are only
// recompiling a single function, extract it from the program.
return (isProgram() ? program : extractFunctionFromScript(program)).setName(null, functionName);
}
private FunctionNode getCachedAst() {
final Object lCachedAst = cachedAst;
// Are we softly caching the AST?
if (lCachedAst instanceof Reference<?>) {
final FunctionNode fn = (FunctionNode)((Reference<?>)lCachedAst).get();
if (fn != null) {
// Yes we are - this is fast
return cloneSymbols(fn);
}
// Are we strongly caching a serialized AST (for split functions only)?
} else if (lCachedAst instanceof SerializedAst) {
final SerializedAst serializedAst = (SerializedAst)lCachedAst;
// Even so, are we also softly caching the AST?
final FunctionNode cachedFn = serializedAst.cachedAst.get();
if (cachedFn != null) {
// Yes we are - this is fast
return cloneSymbols(cachedFn);
}
final FunctionNode deserializedFn = deserialize(serializedAst.serializedAst);
// Softly cache after deserialization, maybe next time we won't need to deserialize
serializedAst.cachedAst = new SoftReference<>(deserializedFn);
return deserializedFn;
}
// No cached representation; return null for reparsing
return null;
}
/**
* Sets the AST to cache in this function
* @param astToCache the new AST to cache
*/
public void setCachedAst(final FunctionNode astToCache) {
assert astToCache.getId() == functionNodeId; // same function
assert !(cachedAst instanceof SerializedAst); // Can't overwrite serialized AST
final boolean isSplit = astToCache.isSplit();
// If we're caching a split function, we're doing it in the eager pass, hence there can be no other
// cached representation already. In other words, isSplit implies cachedAst == null.
assert !isSplit || cachedAst == null; //
final FunctionNode symbolClonedAst = cloneSymbols(astToCache);
final Reference<FunctionNode> ref = new SoftReference<>(symbolClonedAst);
cachedAst = ref;
// Asynchronously serialize split functions.
if (isSplit) {
astSerializerExecutorService.execute(() -> {
cachedAst = new SerializedAst(symbolClonedAst, ref);
});
}
}
/**
* Creates the AST serializer executor service used for in-memory serialization of split functions' ASTs.
* It is created with an unbounded queue (so it can queue any number of pending tasks). Its core and max
* threads is the same, but they are all allowed to time out so when there's no work, they can all go
* away. The threads will be daemons, and they will time out if idle for a minute. Their priority is also
* slightly lower than normal priority as we'd prefer the CPU to keep running the program; serializing
* split function is a memory conservation measure (it allows us to release the AST), it can wait a bit.
* @return an executor service with above described characteristics.
*/
private static ExecutorService createAstSerializerExecutorService() {
final int threads = Math.max(1, Options.getIntProperty("nashorn.serialize.threads", Runtime.getRuntime().availableProcessors() / 2));
final ThreadPoolExecutor service = new ThreadPoolExecutor(threads, threads, 1, TimeUnit.MINUTES, new LinkedBlockingDeque<>(),
(r) -> {
final Thread t = new Thread(r, "Nashorn AST Serializer");
t.setDaemon(true);
t.setPriority(Thread.NORM_PRIORITY - 1);
return t;
});
service.allowCoreThreadTimeOut(true);
return service;
}
/**
* A tuple of a serialized AST and a soft reference to a deserialized AST. This is used to cache split
* functions. Since split functions are altered from their source form, they can't be reparsed from
* source. While we could just use the {@code byte[]} representation in {@link RecompilableScriptFunctionData#cachedAst}
* we're using this tuple instead to also keep a deserialized AST around in memory to cut down on
* deserialization costs.
*/
private static class SerializedAst {
private final byte[] serializedAst;
private volatile Reference<FunctionNode> cachedAst;
SerializedAst(final FunctionNode fn, final Reference<FunctionNode> cachedAst) {
this.serializedAst = AstSerializer.serialize(fn);
this.cachedAst = cachedAst;
}
}
private FunctionNode deserialize(final byte[] serializedAst) {
final ScriptEnvironment env = installer.getContext().getEnv();
final Timing timing = env._timing;
final long t1 = System.nanoTime();
try {
return AstDeserializer.deserialize(serializedAst).initializeDeserialized(source, new Namespace(env.getNamespace()));
} finally {
timing.accumulateTime("'Deserialize'", System.nanoTime() - t1);
}
}
private FunctionNode cloneSymbols(final FunctionNode fn) {
final IdentityHashMap<Symbol, Symbol> symbolReplacements = new IdentityHashMap<>();
final boolean cached = fn.isCached();
// blockDefinedSymbols is used to re-mark symbols defined outside the function as global. We only
// need to do this when we cache an eagerly parsed function (which currently means a split one, as we
// don't cache non-split functions from the eager pass); those already cached, or those not split
// don't need this step.
final Set<Symbol> blockDefinedSymbols = fn.isSplit() && !cached ? Collections.newSetFromMap(new IdentityHashMap<>()) : null;
FunctionNode newFn = (FunctionNode)fn.accept(new SimpleNodeVisitor() {
private Symbol getReplacement(final Symbol original) {
if (original == null) {
return null;
}
final Symbol existingReplacement = symbolReplacements.get(original);
if (existingReplacement != null) {
return existingReplacement;
}
final Symbol newReplacement = original.clone();
symbolReplacements.put(original, newReplacement);
return newReplacement;
}
@Override
public Node leaveIdentNode(final IdentNode identNode) {
final Symbol oldSymbol = identNode.getSymbol();
if (oldSymbol != null) {
final Symbol replacement = getReplacement(oldSymbol);
return identNode.setSymbol(replacement);
}
return identNode;
}
@Override
public Node leaveForNode(final ForNode forNode) {
return ensureUniqueLabels(forNode.setIterator(lc, getReplacement(forNode.getIterator())));
}
@Override
public Node leaveSwitchNode(final SwitchNode switchNode) {
return ensureUniqueLabels(switchNode.setTag(lc, getReplacement(switchNode.getTag())));
}
@Override
public Node leaveTryNode(final TryNode tryNode) {
return ensureUniqueLabels(tryNode.setException(lc, getReplacement(tryNode.getException())));
}
@Override
public boolean enterBlock(final Block block) {
for(final Symbol symbol: block.getSymbols()) {
final Symbol replacement = getReplacement(symbol);
if (blockDefinedSymbols != null) {
blockDefinedSymbols.add(replacement);
}
}
return true;
}
@Override
public Node leaveBlock(final Block block) {
return ensureUniqueLabels(block.replaceSymbols(lc, symbolReplacements));
}
@Override
public Node leaveFunctionNode(final FunctionNode functionNode) {
return functionNode.setParameters(lc, functionNode.visitParameters(this));
}
@Override
protected Node leaveDefault(final Node node) {
return ensureUniqueLabels(node);
};
private Node ensureUniqueLabels(final Node node) {
// If we're returning a cached AST, we must also ensure unique labels
return cached ? node.ensureUniqueLabels(lc) : node;
}
});
if (blockDefinedSymbols != null) {
// Mark all symbols not defined in blocks as globals
Block newBody = null;
for(final Symbol symbol: symbolReplacements.values()) {
if(!blockDefinedSymbols.contains(symbol)) {
assert symbol.isScope(); // must be scope
assert externalScopeDepths.containsKey(symbol.getName()); // must be known to us as an external
// Register it in the function body symbol table as a new global symbol
symbol.setFlags((symbol.getFlags() & ~Symbol.KINDMASK) | Symbol.IS_GLOBAL);
if (newBody == null) {
newBody = newFn.getBody().copyWithNewSymbols();
newFn = newFn.setBody(null, newBody);
}
assert newBody.getExistingSymbol(symbol.getName()) == null; // must not be defined in the body already
newBody.putSymbol(symbol);
}
}
}
return newFn.setCached(null);
}
private boolean getFunctionFlag(final int flag) {
return (functionFlags & flag) != 0;
}
private boolean isProgram() {
return getFunctionFlag(FunctionNode.IS_PROGRAM);
}
TypeMap typeMap(final MethodType fnCallSiteType) {
if (fnCallSiteType == null) {
return null;
}
if (CompiledFunction.isVarArgsType(fnCallSiteType)) {
return null;
}
return new TypeMap(functionNodeId, explicitParams(fnCallSiteType), needsCallee());
}
private static ScriptObject newLocals(final ScriptObject runtimeScope) {
final ScriptObject locals = Global.newEmptyInstance();
locals.setProto(runtimeScope);
return locals;
}
private Compiler getCompiler(final FunctionNode fn, final MethodType actualCallSiteType, final ScriptObject runtimeScope) {
return getCompiler(fn, actualCallSiteType, newLocals(runtimeScope), null, null);
}
/**
* Returns a code installer for installing new code. If we're using either optimistic typing or loader-per-compile,
* then asks for a code installer with a new class loader; otherwise just uses the current installer. We use
* a new class loader with optimistic typing so that deoptimized code can get reclaimed by GC.
* @return a code installer for installing new code.
*/
private CodeInstaller getInstallerForNewCode() {
final ScriptEnvironment env = installer.getContext().getEnv();
return env._optimistic_types || env._loader_per_compile ? installer.getOnDemandCompilationInstaller() : installer;
}
Compiler getCompiler(final FunctionNode functionNode, final MethodType actualCallSiteType,
final ScriptObject runtimeScope, final Map<Integer, Type> invalidatedProgramPoints,
final int[] continuationEntryPoints) {
final TypeMap typeMap = typeMap(actualCallSiteType);
final Type[] paramTypes = typeMap == null ? null : typeMap.getParameterTypes(functionNodeId);
final Object typeInformationFile = OptimisticTypesPersistence.getLocationDescriptor(source, functionNodeId, paramTypes);
return Compiler.forOnDemandCompilation(
getInstallerForNewCode(),
functionNode.getSource(), // source
isStrict() | functionNode.isStrict(), // is strict
this, // compiledFunction, i.e. this RecompilableScriptFunctionData
typeMap, // type map
getEffectiveInvalidatedProgramPoints(invalidatedProgramPoints, typeInformationFile), // invalidated program points
typeInformationFile,
continuationEntryPoints, // continuation entry points
runtimeScope); // runtime scope
}
/**
* If the function being compiled already has its own invalidated program points map, use it. Otherwise, attempt to
* load invalidated program points map from the persistent type info cache.
* @param invalidatedProgramPoints the function's current invalidated program points map. Null if the function
* doesn't have it.
* @param typeInformationFile the object describing the location of the persisted type information.
* @return either the existing map, or a loaded map from the persistent type info cache, or a new empty map if
* neither an existing map or a persistent cached type info is available.
*/
@SuppressWarnings("unused")
private static Map<Integer, Type> getEffectiveInvalidatedProgramPoints(
final Map<Integer, Type> invalidatedProgramPoints, final Object typeInformationFile) {
if(invalidatedProgramPoints != null) {
return invalidatedProgramPoints;
}
final Map<Integer, Type> loadedProgramPoints = OptimisticTypesPersistence.load(typeInformationFile);
return loadedProgramPoints != null ? loadedProgramPoints : new TreeMap<Integer, Type>();
}
private FunctionInitializer compileTypeSpecialization(final MethodType actualCallSiteType, final ScriptObject runtimeScope, final boolean persist) {
// We're creating an empty script object for holding local variables. AssignSymbols will populate it with
// explicit Undefined values for undefined local variables (see AssignSymbols#defineSymbol() and
// CompilationEnvironment#declareLocalSymbol()).
if (log.isEnabled()) {
log.info("Parameter type specialization of '", functionName, "' signature: ", actualCallSiteType);
}
final boolean persistentCache = persist && usePersistentCodeCache();
String cacheKey = null;
if (persistentCache) {
final TypeMap typeMap = typeMap(actualCallSiteType);
final Type[] paramTypes = typeMap == null ? null : typeMap.getParameterTypes(functionNodeId);
cacheKey = CodeStore.getCacheKey(functionNodeId, paramTypes);
final CodeInstaller newInstaller = getInstallerForNewCode();
final StoredScript script = newInstaller.loadScript(source, cacheKey);
if (script != null) {
Compiler.updateCompilationId(script.getCompilationId());
return script.installFunction(this, newInstaller);
}
}
final FunctionNode fn = reparse();
final Compiler compiler = getCompiler(fn, actualCallSiteType, runtimeScope);
final FunctionNode compiledFn = compiler.compile(fn,
fn.isCached() ? CompilationPhases.COMPILE_ALL_CACHED : CompilationPhases.COMPILE_ALL);
if (persist && !compiledFn.hasApplyToCallSpecialization()) {
compiler.persistClassInfo(cacheKey, compiledFn);
}
return new FunctionInitializer(compiledFn, compiler.getInvalidatedProgramPoints());
}
boolean usePersistentCodeCache() {
return installer != null && installer.getContext().getEnv()._persistent_cache;
}
private MethodType explicitParams(final MethodType callSiteType) {
if (CompiledFunction.isVarArgsType(callSiteType)) {
return null;
}
final MethodType noCalleeThisType = callSiteType.dropParameterTypes(0, 2); // (callee, this) is always in call site type
final int callSiteParamCount = noCalleeThisType.parameterCount();
// Widen parameters of reference types to Object as we currently don't care for specialization among reference
// types. E.g. call site saying (ScriptFunction, Object, String) should still link to (ScriptFunction, Object, Object)
final Class<?>[] paramTypes = noCalleeThisType.parameterArray();
boolean changed = false;
for (int i = 0; i < paramTypes.length; ++i) {
final Class<?> paramType = paramTypes[i];
if (!(paramType.isPrimitive() || paramType == Object.class)) {
paramTypes[i] = Object.class;
changed = true;
}
}
final MethodType generalized = changed ? MethodType.methodType(noCalleeThisType.returnType(), paramTypes) : noCalleeThisType;
if (callSiteParamCount < getArity()) {
return generalized.appendParameterTypes(Collections.<Class<?>>nCopies(getArity() - callSiteParamCount, Object.class));
}
return generalized;
}
private FunctionNode extractFunctionFromScript(final FunctionNode script) {
final Set<FunctionNode> fns = new HashSet<>();
script.getBody().accept(new SimpleNodeVisitor() {
@Override
public boolean enterFunctionNode(final FunctionNode fn) {
fns.add(fn);
return false;
}
});
assert fns.size() == 1 : "got back more than one method in recompilation";
final FunctionNode f = fns.iterator().next();
assert f.getId() == functionNodeId;
if (!getFunctionFlag(FunctionNode.IS_DECLARED) && f.isDeclared()) {
return f.clearFlag(null, FunctionNode.IS_DECLARED);
}
return f;
}
private void logLookup(final boolean shouldLog, final MethodType targetType) {
if (shouldLog && log.isEnabled()) {
log.info("Looking up ", DebugLogger.quote(functionName), " type=", targetType);
}
}
private MethodHandle lookup(final FunctionInitializer fnInit, final boolean shouldLog) {
final MethodType type = fnInit.getMethodType();
logLookup(shouldLog, type);
return lookupCodeMethod(fnInit.getCode(), type);
}
MethodHandle lookup(final FunctionNode fn) {
final MethodType type = new FunctionSignature(fn).getMethodType();
logLookup(true, type);
return lookupCodeMethod(fn.getCompileUnit().getCode(), type);
}
MethodHandle lookupCodeMethod(final Class<?> codeClass, final MethodType targetType) {
return MH.findStatic(LOOKUP, codeClass, functionName, targetType);
}
/**
* Initializes this function data with the eagerly generated version of the code. This method can only be invoked
* by the compiler internals in Nashorn and is public for implementation reasons only. Attempting to invoke it
* externally will result in an exception.
*
* @param functionNode FunctionNode for this data
*/
public void initializeCode(final FunctionNode functionNode) {
// Since the method is public, we double-check that we aren't invoked with an inappropriate compile unit.
if (!code.isEmpty() || functionNode.getId() != functionNodeId || !functionNode.getCompileUnit().isInitializing(this, functionNode)) {
throw new IllegalStateException(name);
}
addCode(lookup(functionNode), null, null, functionNode.getFlags());
}
/**
* Initializes this function with the given function code initializer.
* @param initializer function code initializer
*/
void initializeCode(final FunctionInitializer initializer) {
addCode(lookup(initializer, true), null, null, initializer.getFlags());
}
private CompiledFunction addCode(final MethodHandle target, final Map<Integer, Type> invalidatedProgramPoints,
final MethodType callSiteType, final int fnFlags) {
final CompiledFunction cfn = new CompiledFunction(target, this, invalidatedProgramPoints, callSiteType, fnFlags);
assert noDuplicateCode(cfn) : "duplicate code";
code.add(cfn);
return cfn;
}
/**
* Add code with specific call site type. It will adapt the type of the looked up method handle to fit the call site
* type. This is necessary because even if we request a specialization that takes an "int" parameter, we might end
* up getting one that takes a "double" etc. because of internal function logic causes widening (e.g. assignment of
* a wider value to the parameter variable). However, we use the method handle type for matching subsequent lookups
* for the same specialization, so we must adapt the handle to the expected type.
* @param fnInit the function
* @param callSiteType the call site type
* @return the compiled function object, with its type matching that of the call site type.
*/
private CompiledFunction addCode(final FunctionInitializer fnInit, final MethodType callSiteType) {
if (isVariableArity()) {
return addCode(lookup(fnInit, true), fnInit.getInvalidatedProgramPoints(), callSiteType, fnInit.getFlags());
}
final MethodHandle handle = lookup(fnInit, true);
final MethodType fromType = handle.type();
MethodType toType = needsCallee(fromType) ? callSiteType.changeParameterType(0, ScriptFunction.class) : callSiteType.dropParameterTypes(0, 1);
toType = toType.changeReturnType(fromType.returnType());
final int toCount = toType.parameterCount();
final int fromCount = fromType.parameterCount();
final int minCount = Math.min(fromCount, toCount);
for(int i = 0; i < minCount; ++i) {
final Class<?> fromParam = fromType.parameterType(i);
final Class<?> toParam = toType.parameterType(i);
// If method has an Object parameter, but call site had String, preserve it as Object. No need to narrow it
// artificially. Note that this is related to how CompiledFunction.matchesCallSite() works, specifically
// the fact that various reference types compare to equal (see "fnType.isEquivalentTo(csType)" there).
if (fromParam != toParam && !fromParam.isPrimitive() && !toParam.isPrimitive()) {
assert fromParam.isAssignableFrom(toParam);
toType = toType.changeParameterType(i, fromParam);
}
}
if (fromCount > toCount) {
toType = toType.appendParameterTypes(fromType.parameterList().subList(toCount, fromCount));
} else if (fromCount < toCount) {
toType = toType.dropParameterTypes(fromCount, toCount);
}
return addCode(lookup(fnInit, false).asType(toType), fnInit.getInvalidatedProgramPoints(), callSiteType, fnInit.getFlags());
}
/**
* Returns the return type of a function specialization for particular parameter types.<br>
* <b>Be aware that the way this is implemented, it forces full materialization (compilation and installation) of
* code for that specialization.</b>
* @param callSiteType the parameter types at the call site. It must include the mandatory {@code callee} and
* {@code this} parameters, so it needs to start with at least {@code ScriptFunction.class} and
* {@code Object.class} class. Since the return type of the function is calculated from the code itself, it is
* irrelevant and should be set to {@code Object.class}.
* @param runtimeScope a current runtime scope. Can be null but when it's present it will be used as a source of
* current runtime values that can improve the compiler's type speculations (and thus reduce the need for later
* recompilations) if the specialization is not already present and thus needs to be freshly compiled.
* @return the return type of the function specialization.
*/
public Class<?> getReturnType(final MethodType callSiteType, final ScriptObject runtimeScope) {
return getBest(callSiteType, runtimeScope, CompiledFunction.NO_FUNCTIONS).type().returnType();
}
@Override
synchronized CompiledFunction getBest(final MethodType callSiteType, final ScriptObject runtimeScope, final Collection<CompiledFunction> forbidden, final boolean linkLogicOkay) {
assert isValidCallSite(callSiteType) : callSiteType;
CompiledFunction existingBest = pickFunction(callSiteType, false);
if (existingBest == null) {
existingBest = pickFunction(callSiteType, true); // try vararg last
}
if (existingBest == null) {
existingBest = addCode(compileTypeSpecialization(callSiteType, runtimeScope, true), callSiteType);
}
assert existingBest != null;
//if the best one is an apply to call, it has to match the callsite exactly
//or we need to regenerate
if (existingBest.isApplyToCall()) {
final CompiledFunction best = lookupExactApplyToCall(callSiteType);
if (best != null) {
return best;
}
// special case: we had an apply to call, but we failed to make it fit.
// Try to generate a specialized one for this callsite. It may
// be another apply to call specialization, or it may not, but whatever
// it is, it is a specialization that is guaranteed to fit
existingBest = addCode(compileTypeSpecialization(callSiteType, runtimeScope, false), callSiteType);
}
return existingBest;
}
@Override
public boolean needsCallee() {
return getFunctionFlag(FunctionNode.NEEDS_CALLEE);
}
/**
* Returns the {@link FunctionNode} flags associated with this function data.
* @return the {@link FunctionNode} flags associated with this function data.
*/
public int getFunctionFlags() {
return functionFlags;
}
@Override
MethodType getGenericType() {
// 2 is for (callee, this)
if (isVariableArity()) {
return MethodType.genericMethodType(2, true);
}
return MethodType.genericMethodType(2 + getArity());
}
/**
* Return the function node id.
* @return the function node id
*/
public int getFunctionNodeId() {
return functionNodeId;
}
/**
* Get the source for the script
* @return source
*/
public Source getSource() {
return source;
}
/**
* Return a script function data based on a function id, either this function if
* the id matches or a nested function based on functionId. This goes down into
* nested functions until all leaves are exhausted.
*
* @param functionId function id
* @return script function data or null if invalid id
*/
public RecompilableScriptFunctionData getScriptFunctionData(final int functionId) {
if (functionId == functionNodeId) {
return this;
}
RecompilableScriptFunctionData data;
data = nestedFunctions == null ? null : nestedFunctions.get(functionId);
if (data != null) {
return data;
}
for (final RecompilableScriptFunctionData ndata : nestedFunctions.values()) {
data = ndata.getScriptFunctionData(functionId);
if (data != null) {
return data;
}
}
return null;
}
/**
* Check whether a certain name is a global symbol, i.e. only exists as defined
* in outermost scope and not shadowed by being parameter or assignment in inner
* scopes
*
* @param functionNode function node to check
* @param symbolName symbol name
* @return true if global symbol
*/
public boolean isGlobalSymbol(final FunctionNode functionNode, final String symbolName) {
RecompilableScriptFunctionData data = getScriptFunctionData(functionNode.getId());
assert data != null;
do {
if (data.hasInternalSymbol(symbolName)) {
return false;
}
data = data.getParent();
} while(data != null);
return true;
}
/**
* Restores the {@link #getFunctionFlags()} flags to a function node. During on-demand compilation, we might need
* to restore flags to a function node that was otherwise not subjected to a full compile pipeline (e.g. its parse
* was skipped, or it's a nested function of a deserialized function.
* @param lc current lexical context
* @param fn the function node to restore flags onto
* @return the transformed function node
*/
public FunctionNode restoreFlags(final LexicalContext lc, final FunctionNode fn) {
assert fn.getId() == functionNodeId;
FunctionNode newFn = fn.setFlags(lc, functionFlags);
// This compensates for missing markEval() in case the function contains an inner function
// that contains eval(), that now we didn't discover since we skipped the inner function.
if (newFn.hasNestedEval()) {
assert newFn.hasScopeBlock();
newFn = newFn.setBody(lc, newFn.getBody().setNeedsScope(null));
}
return newFn;
}
// Make sure code does not contain a compiled function with the same signature as compiledFunction
private boolean noDuplicateCode(final CompiledFunction compiledFunction) {
for (final CompiledFunction cf : code) {
if (cf.type().equals(compiledFunction.type())) {
return false;
}
}
return true;
}
private void readObject(final java.io.ObjectInputStream in) throws IOException, ClassNotFoundException {
in.defaultReadObject();
createLogger();
}
private void createLogger() {
log = initLogger(Context.getContextTrusted());
}
}