/*
* Copyright 2005 The Closure Compiler Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.javascript.jscomp;
import com.google.common.base.Preconditions;
import com.google.common.base.Supplier;
import com.google.javascript.jscomp.FunctionInjector.CanInlineResult;
import com.google.javascript.jscomp.FunctionInjector.InliningMode;
import com.google.javascript.jscomp.NodeTraversal.AbstractPostOrderCallback;
import com.google.javascript.jscomp.NodeTraversal.Callback;
import com.google.javascript.rhino.Node;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
/**
* Inlines functions that are divided into two types: "direct call node
* replacement" (aka "direct") and as a block of statements (aka block).
* Function that can be inlined "directly" functions consist of a single
* return statement, everything else is must be inlined as a "block". These
* functions must meet these general requirements:
* - it is not recursive
* - the function does not contain another function -- these may be
* intentional to to limit the scope of closures.
* - function is called only once OR the size of the inline function is smaller
* than the call itself.
* - the function name is not referenced in any other manner
*
* "directly" inlined functions must meet these additional requirements:
* - consists of a single return statement
*
* @author johnlenz@google.com (John Lenz)
*/
class InlineFunctions implements CompilerPass {
// TODO(nicksantos): This needs to be completely rewritten to use scopes
// to do variable lookups. Right now, it assumes that all functions are
// uniquely named variables. There's currently a stopgap scope-check
// to ensure that this doesn't produce invalid code. But in the long run,
// this needs a major refactor.
private final Map<String, FunctionState> fns = new LinkedHashMap<>();
private final Map<Node, String> anonFns = new HashMap<>();
private final AbstractCompiler compiler;
private final FunctionInjector injector;
private final boolean blockFunctionInliningEnabled;
private final boolean inlineGlobalFunctions;
private final boolean inlineLocalFunctions;
private final boolean assumeMinimumCapture;
private final boolean enforceMaxSizeAfterInlining;
private final int maxSizeAfterInlining;
InlineFunctions(AbstractCompiler compiler,
Supplier<String> safeNameIdSupplier,
boolean inlineGlobalFunctions,
boolean inlineLocalFunctions,
boolean blockFunctionInliningEnabled,
boolean assumeStrictThis,
boolean assumeMinimumCapture,
int maxSizeAfterInlining) {
Preconditions.checkArgument(compiler != null);
Preconditions.checkArgument(safeNameIdSupplier != null);
this.compiler = compiler;
this.inlineGlobalFunctions = inlineGlobalFunctions;
this.inlineLocalFunctions = inlineLocalFunctions;
this.blockFunctionInliningEnabled = blockFunctionInliningEnabled;
this.assumeMinimumCapture = assumeMinimumCapture;
this.maxSizeAfterInlining = maxSizeAfterInlining;
this.enforceMaxSizeAfterInlining =
maxSizeAfterInlining != CompilerOptions.UNLIMITED_FUN_SIZE_AFTER_INLINING;
this.injector = new FunctionInjector(
compiler, safeNameIdSupplier, true, assumeStrictThis, assumeMinimumCapture);
}
FunctionState getOrCreateFunctionState(String fnName) {
FunctionState fs = fns.get(fnName);
if (fs == null) {
fs = new FunctionState();
fns.put(fnName, fs);
}
return fs;
}
@Override
public void process(Node externs, Node root) {
Preconditions.checkState(compiler.getLifeCycleStage().isNormalized());
NodeTraversal.traverseEs6(compiler, root, new FindCandidateFunctions());
if (fns.isEmpty()) {
return; // Nothing left to do.
}
NodeTraversal.traverseEs6(compiler, root,
new FindCandidatesReferences(fns, anonFns));
trimCandidatesNotMeetingMinimumRequirements();
if (fns.isEmpty()) {
return; // Nothing left to do.
}
// Store the set of function names eligible for inlining and use this to
// prevent function names from being moved into temporaries during
// expression decomposition. If this movement were allowed it would prevent
// the Inline callback from finding the function calls.
//
// This pass already assumes these are constants, so this is safe for anyone
// using function inlining.
//
Set<String> fnNames = new HashSet<>(fns.keySet());
injector.setKnownConstants(fnNames);
trimCandidatesUsingOnCost();
if (fns.isEmpty()) {
return; // Nothing left to do.
}
resolveInlineConflicts();
decomposeExpressions();
NodeTraversal.traverseEs6(compiler, root,
new CallVisitor(fns, anonFns, new Inline(injector)));
removeInlinedFunctions();
}
private static boolean isAlwaysInlinable(Node fn) {
Preconditions.checkArgument(fn.isFunction());
Node body = NodeUtil.getFunctionBody(fn);
return (!body.hasChildren())
|| (body.hasOneChild() && body.getFirstChild().isReturn());
}
private boolean targetSizeAfterInlineExceedsLimit(
NodeTraversal t, FunctionState fs) {
Node containingFunction = t.getEnclosingFunction();
// Always inline at the top level,
// unless maybeAddFunction has marked fs as not inlinable.
if (containingFunction == null) {
return false;
}
Node inlinedFun = fs.getFn().getFunctionNode();
if (isAlwaysInlinable(inlinedFun)) {
return false;
}
int inlinedFunSize = NodeUtil.countAstSizeUpToLimit(
NodeUtil.getFunctionBody(inlinedFun), maxSizeAfterInlining);
int targetFunSize = NodeUtil.countAstSizeUpToLimit(
containingFunction, maxSizeAfterInlining);
return inlinedFunSize + targetFunSize > maxSizeAfterInlining;
}
/**
* Find functions that might be inlined.
*/
private class FindCandidateFunctions implements Callback {
private int callsSeen = 0;
@Override
public boolean shouldTraverse(
NodeTraversal nodeTraversal, Node n, Node parent) {
// Don't traverse into function bodies
// if we aren't inlining local functions.
return inlineLocalFunctions || nodeTraversal.inGlobalHoistScope();
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
if ((t.inGlobalHoistScope() && inlineGlobalFunctions)
|| (!t.inGlobalHoistScope() && inlineLocalFunctions)) {
findNamedFunctions(t, n, parent);
findFunctionExpressions(t, n);
}
}
public void findNamedFunctions(NodeTraversal t, Node n, Node parent) {
if (!NodeUtil.isStatement(n)) {
// There aren't any interesting functions here.
return;
}
switch (n.getToken()) {
// Functions expressions in the form of:
// var fooFn = function(x) { return ... }
case VAR:
Preconditions.checkState(n.hasOneChild(), n);
Node nameNode = n.getFirstChild();
if (nameNode.isName()
&& nameNode.hasChildren()
&& nameNode.getFirstChild().isFunction()) {
maybeAddFunction(new FunctionVar(n), t.getModule());
}
break;
// Named functions
// function Foo(x) { return ... }
case FUNCTION:
Preconditions.checkState(NodeUtil.isStatementBlock(parent)
|| parent.isLabel());
if (!NodeUtil.isFunctionExpression(n)) {
Function fn = new NamedFunction(n);
maybeAddFunction(fn, t.getModule());
}
break;
default:
break;
}
}
/**
* Find function expressions that are called directly in the form of
* (function(a,b,...){...})(a,b,...)
* or
* (function(a,b,...){...}).call(this,a,b, ...)
*/
public void findFunctionExpressions(NodeTraversal t, Node n) {
switch (n.getToken()) {
// Functions expressions in the form of:
// (function(){})();
case CALL:
Node fnNode = null;
if (n.getFirstChild().isFunction()) {
fnNode = n.getFirstChild();
} else if (NodeUtil.isFunctionObjectCall(n)) {
Node fnIdentifingNode = n.getFirstFirstChild();
if (fnIdentifingNode.isFunction()) {
fnNode = fnIdentifingNode;
}
}
// If a interesting function was discovered, add it.
if (fnNode != null) {
Function fn = new FunctionExpression(fnNode, callsSeen++);
maybeAddFunction(fn, t.getModule());
anonFns.put(fnNode, fn.getName());
}
break;
default:
break;
}
}
}
/**
* Updates the FunctionState object for the given function. Checks if the
* given function matches the criteria for an inlinable function.
*/
private void maybeAddFunction(Function fn, JSModule module) {
String name = fn.getName();
FunctionState fs = getOrCreateFunctionState(name);
// TODO(johnlenz): Maybe "smarten" FunctionState by adding this logic
// to it?
// If the function has multiple definitions, don't inline it.
if (fs.hasExistingFunctionDefinition()) {
fs.setInline(false);
return;
}
Node fnNode = fn.getFunctionNode();
if (enforceMaxSizeAfterInlining
&& !isAlwaysInlinable(fnNode)
&& maxSizeAfterInlining
<= NodeUtil.countAstSizeUpToLimit(fnNode, maxSizeAfterInlining)) {
fs.setInline(false);
return;
}
// verify the function hasn't already been marked as "don't inline"
if (fs.canInline()) {
// store it for use when inlining.
fs.setFn(fn);
if (FunctionInjector.isDirectCallNodeReplacementPossible(
fn.getFunctionNode())) {
fs.inlineDirectly(true);
}
// verify the function meets all the requirements.
// TODO(johnlenz): Minimum requirement checks are about 5% of the
// run-time cost of this pass.
if (!isCandidateFunction(fn)) {
// It doesn't meet the requirements.
fs.setInline(false);
}
// Set the module and gather names that need temporaries.
if (fs.canInline()) {
fs.setModule(module);
Set<String> namesToAlias =
FunctionArgumentInjector.findModifiedParameters(fnNode);
if (!namesToAlias.isEmpty()) {
fs.inlineDirectly(false);
fs.setNamesToAlias(namesToAlias);
}
Node block = NodeUtil.getFunctionBody(fnNode);
if (NodeUtil.referencesThis(block)) {
fs.setReferencesThis(true);
}
if (NodeUtil.containsFunction(block)) {
fs.setHasInnerFunctions(true);
// If there are inner functions, we can inline into global scope
// if there are no local vars or named functions.
// TODO(johnlenz): this can be improved by looking at the possible
// values for locals. If there are simple values, or constants
// we could still inline.
if (!assumeMinimumCapture && hasLocalNames(fnNode)) {
fs.setInline(false);
}
}
}
// Check if block inlining is allowed.
if (fs.canInline() && !fs.canInlineDirectly() && !blockFunctionInliningEnabled) {
fs.setInline(false);
}
}
}
/**
* @param fnNode The function to inspect.
* @return Whether the function has parameters, var, or function declarations.
*/
private static boolean hasLocalNames(Node fnNode) {
Node block = NodeUtil.getFunctionBody(fnNode);
return NodeUtil.getFunctionParameters(fnNode).hasChildren()
|| NodeUtil.has(
block,
new NodeUtil.MatchDeclaration(),
new NodeUtil.MatchShallowStatement());
}
/**
* Checks if the given function matches the criteria for an inlinable
* function.
*/
private boolean isCandidateFunction(Function fn) {
// Don't inline exported functions.
String fnName = fn.getName();
if (compiler.getCodingConvention().isExported(fnName)) {
// TODO(johnlenz): Should we allow internal references to be inlined?
// An exported name can be replaced externally, any inlined instance
// would not reflect this change.
// To allow inlining we need to be able to distinguish between exports
// that are used in a read-only fashion and those that can be replaced
// by external definitions.
return false;
}
// Don't inline this special function
if (compiler.getCodingConvention().isPropertyRenameFunction(fnName)) {
return false;
}
Node fnNode = fn.getFunctionNode();
return injector.doesFunctionMeetMinimumRequirements(fnName, fnNode);
}
/**
* @see CallVisitor
*/
private interface CallVisitorCallback {
public void visitCallSite(
NodeTraversal t, Node callNode, FunctionState fs);
}
/**
* Visit call sites for functions in functionMap.
*/
private static class CallVisitor extends AbstractPostOrderCallback {
protected CallVisitorCallback callback;
private Map<String, FunctionState> functionMap;
private Map<Node, String> anonFunctionMap;
CallVisitor(Map<String, FunctionState> fns,
Map<Node, String> anonFns,
CallVisitorCallback callback) {
this.functionMap = fns;
this.anonFunctionMap = anonFns;
this.callback = callback;
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
switch (n.getToken()) {
// Function calls
case CALL:
Node child = n.getFirstChild();
String name = null;
// NOTE: The normalization pass insures that local names do not
// collide with global names.
if (child.isName()) {
name = child.getString();
} else if (child.isFunction()) {
name = anonFunctionMap.get(child);
} else if (NodeUtil.isFunctionObjectCall(n)) {
Preconditions.checkState(NodeUtil.isGet(child));
Node fnIdentifingNode = child.getFirstChild();
if (fnIdentifingNode.isName()) {
name = fnIdentifingNode.getString();
} else if (fnIdentifingNode.isFunction()) {
name = anonFunctionMap.get(fnIdentifingNode);
}
}
if (name != null) {
FunctionState fs = functionMap.get(name);
// Only visit call-sites for functions that can be inlined.
if (fs != null) {
callback.visitCallSite(t, n, fs);
}
}
break;
default:
break;
}
}
}
/**
* @return Whether the name is used in a way that might be a candidate
* for inlining.
*/
static boolean isCandidateUsage(Node name) {
Node parent = name.getParent();
Preconditions.checkState(name.isName());
if (parent.isVar() || parent.isFunction()) {
// This is a declaration. Duplicate declarations are handle during
// function candidate gathering.
return true;
}
if (parent.isCall() && parent.getFirstChild() == name) {
// This is a normal reference to the function.
return true;
}
// Check for a ".call" to the named function:
// CALL
// GETPROP/GETELEM
// NAME
// STRING == "call"
// This-Value
// Function-parameter-1
// ...
if (NodeUtil.isGet(parent)
&& name == parent.getFirstChild()
&& name.getNext().isString()
&& name.getNext().getString().equals("call")) {
Node grandparent = name.getAncestor(2);
if (grandparent.isCall()
&& grandparent.getFirstChild() == parent) {
// Yep, a ".call".
return true;
}
}
return false;
}
/**
* Find references to functions that are inlinable.
*/
private class FindCandidatesReferences
extends CallVisitor
implements CallVisitorCallback {
FindCandidatesReferences(
Map<String, FunctionState> fns,
Map<Node, String> anonFns) {
super(fns, anonFns, null);
this.callback = this;
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
super.visit(t, n, parent);
if (n.isName()) {
checkNameUsage(n, parent);
}
}
@Override
public void visitCallSite(
NodeTraversal t, Node callNode, FunctionState fs) {
maybeAddReference(t, fs, callNode, t.getModule());
}
void maybeAddReference(NodeTraversal t, FunctionState fs,
Node callNode, JSModule module) {
if (!fs.canInline()) {
return;
}
InliningMode mode = fs.canInlineDirectly()
? InliningMode.DIRECT : InliningMode.BLOCK;
boolean referenceAdded = maybeAddReferenceUsingMode(t, fs, callNode, module, mode);
if (!referenceAdded && mode == InliningMode.DIRECT && blockFunctionInliningEnabled) {
// This reference can not be directly inlined, see if
// block replacement inlining is possible.
mode = InliningMode.BLOCK;
referenceAdded = maybeAddReferenceUsingMode(
t, fs, callNode, module, mode);
}
if (!referenceAdded) {
// Don't try to remove a function if we can't inline all
// the references.
fs.setRemove(false);
}
}
private boolean maybeAddReferenceUsingMode(
NodeTraversal t, FunctionState fs, Node callNode,
JSModule module, InliningMode mode) {
// If many functions are inlined into the same function F in the same
// inlining round, then the size of F may exceed the max size.
// This could be avoided if we bail later, during the inlining phase, eg,
// in Inline#visitCallSite. However, that is not safe, because at that
// point expression decomposition has already run, and we want to
// decompose expressions only for the calls that are actually inlined.
if (enforceMaxSizeAfterInlining
&& targetSizeAfterInlineExceedsLimit(t, fs)) {
return false;
}
Reference candidate = new Reference(callNode, t.getScope(), module, mode);
CanInlineResult result = injector.canInlineReferenceToFunction(
candidate, fs.getFn().getFunctionNode(),
fs.getNamesToAlias(), fs.getReferencesThis(),
fs.hasInnerFunctions());
if (result != CanInlineResult.NO) {
// Yeah!
candidate.setRequiresDecomposition(
result == CanInlineResult.AFTER_PREPARATION);
fs.addReference(candidate);
return true;
}
return false;
}
/**
* Find functions that can be inlined.
*/
private void checkNameUsage(Node n, Node parent) {
Preconditions.checkState(n.isName(), n);
if (isCandidateUsage(n)) {
return;
}
// Other refs to a function name remove its candidacy for inlining
String name = n.getString();
FunctionState fs = fns.get(name);
if (fs == null) {
return;
}
// Unlike normal call/new parameters, references passed to
// JSCompiler_ObjectPropertyString are not aliases of a value, but
// a reference to the name itself, as such the value of the name is
// unknown and can not be inlined.
if (parent.isNew()) {
Node target = parent.getFirstChild();
if (target.isName() && target.getString().equals(
NodeUtil.EXTERN_OBJECT_PROPERTY_STRING)) {
// This method is going to be replaced so don't inline it anywhere.
fs.setInline(false);
}
}
// If the name is being assigned to it can not be inlined.
if (parent.isAssign() && parent.getFirstChild() == n) {
// e.g. bar = something; <== we can't inline "bar"
// so mark the function as uninlinable.
// TODO(johnlenz): Should we just remove it from fns here?
fs.setInline(false);
} else {
// e.g. var fn = bar; <== we can't inline "bar"
// As this reference can't be inlined mark the function as
// unremovable.
fs.setRemove(false);
}
}
}
/**
* Inline functions at the call sites.
*/
private static class Inline implements CallVisitorCallback {
private final FunctionInjector injector;
Inline(FunctionInjector injector) {
this.injector = injector;
}
@Override
public void visitCallSite(
NodeTraversal t, Node callNode, FunctionState fs) {
Preconditions.checkState(fs.hasExistingFunctionDefinition());
if (fs.canInline()) {
Reference ref = fs.getReference(callNode);
// There are two cases ref can be null: if the call site was introduced
// because it was part of a function that was inlined during this pass
// or if the call site was trimmed from the list of references because
// the function couldn't be inlined at this location.
if (ref != null) {
inlineFunction(t, ref, fs);
// Keep track of references that have been inlined so that
// we can verify that none have been missed.
ref.inlined = true;
}
}
}
/**
* Inline a function into the call site.
*/
private void inlineFunction(
NodeTraversal t, Reference ref, FunctionState fs) {
Function fn = fs.getFn();
String fnName = fn.getName();
Node fnNode = fs.getSafeFnNode();
Node newExpr = injector.inline(ref, fnName, fnNode);
if (!newExpr.isEquivalentTo(ref.callNode)) {
t.getCompiler().reportChangeToEnclosingScope(newExpr);
}
t.getCompiler().addToDebugLog("Inlined function: " + fn.getName());
}
}
/**
* Remove entries that aren't a valid inline candidates, from the list of
* encountered names.
*/
private void trimCandidatesNotMeetingMinimumRequirements() {
Iterator<Entry<String, FunctionState>> i;
for (i = fns.entrySet().iterator(); i.hasNext();) {
FunctionState fs = i.next().getValue();
if (!fs.hasExistingFunctionDefinition() || !fs.canInline()) {
i.remove();
}
}
}
/**
* Remove entries from the list of candidates that can't be inlined.
*/
private void trimCandidatesUsingOnCost() {
Iterator<Entry<String, FunctionState>> i;
for (i = fns.entrySet().iterator(); i.hasNext();) {
FunctionState fs = i.next().getValue();
if (fs.hasReferences()) {
// Only inline function if it decreases the code size.
boolean lowersCost = minimizeCost(fs);
if (!lowersCost) {
// It shouldn't be inlined; remove it from the list.
i.remove();
}
} else if (!fs.canRemove()) {
// Don't bother tracking functions without references that can't be
// removed.
i.remove();
}
}
}
/**
* Determines if the function is worth inlining and potentially
* trims references that increase the cost.
* @return Whether inlining the references lowers the overall cost.
*/
private boolean minimizeCost(FunctionState fs) {
if (!inliningLowersCost(fs)) {
// Try again without Block inlining references
if (fs.hasBlockInliningReferences()) {
fs.setRemove(false);
fs.removeBlockInliningReferences();
if (!fs.hasReferences() || !inliningLowersCost(fs)) {
return false;
}
} else {
return false;
}
}
return true;
}
/**
* @return Whether inlining the function reduces code size.
*/
private boolean inliningLowersCost(FunctionState fs) {
return injector.inliningLowersCost(
fs.getModule(),
fs.getFn().getFunctionNode(),
fs.getReferences(),
fs.getNamesToAlias(),
fs.canRemove(),
fs.getReferencesThis());
}
/**
* Size base inlining calculations are thrown off when a function that is
* being inlined also contains calls to functions that are slated for
* inlining.
*
* Specifically, a clone of the FUNCTION node tree is used when the function
* is inlined. Calls in this new tree are not included in the list of function
* references so they won't be inlined (which is what we want). Here we mark
* those functions as non-removable (as they will have new references in the
* cloned node trees).
*
* This prevents a function that would only be inlined because it is
* referenced once from being inlined into multiple call sites because
* the calling function has been inlined in multiple locations or the
* function being removed while there are still references.
*/
private void resolveInlineConflicts() {
for (FunctionState fs : fns.values()) {
resolveInlineConflictsForFunction(fs);
}
}
/**
* @see #resolveInlineConflicts
*/
private void resolveInlineConflictsForFunction(FunctionState fs) {
// Functions that aren't referenced don't cause conflicts.
if (!fs.hasReferences() || !fs.canInline()) {
return;
}
Node fnNode = fs.getFn().getFunctionNode();
Set<String> names = findCalledFunctions(fnNode);
if (!names.isEmpty()) {
// Prevent the removal of the referenced functions.
for (String name : names) {
FunctionState fsCalled = fns.get(name);
if (fsCalled != null && fsCalled.canRemove()) {
fsCalled.setRemove(false);
// For functions that can no longer be removed, check if they should
// still be inlined.
if (!minimizeCost(fsCalled)) {
// It can't be inlined remove it from the list.
fsCalled.setInline(false);
}
}
}
// Make a copy of the Node, so it isn't changed by other inlines.
fs.setSafeFnNode(fs.getFn().getFunctionNode().cloneTree());
}
}
/**
* This functions that may be called directly.
*/
private Set<String> findCalledFunctions(Node node) {
Set<String> changed = new HashSet<>();
findCalledFunctions(NodeUtil.getFunctionBody(node), changed);
return changed;
}
/**
* @see #findCalledFunctions(Node)
*/
private static void findCalledFunctions(
Node node, Set<String> changed) {
Preconditions.checkArgument(changed != null);
// For each referenced function, add a new reference
if (node.isName() && isCandidateUsage(node)) {
changed.add(node.getString());
}
for (Node c = node.getFirstChild(); c != null; c = c.getNext()) {
findCalledFunctions(c, changed);
}
}
/**
* For any call-site that needs it, prepare the call-site for inlining
* by rewriting the containing expression.
*/
private void decomposeExpressions() {
for (FunctionState fs : fns.values()) {
if (fs.canInline()) {
for (Reference ref : fs.getReferences()) {
if (ref.requiresDecomposition) {
injector.maybePrepareCall(ref);
}
}
}
}
}
/**
* Removed inlined functions that no longer have any references.
*/
void removeInlinedFunctions() {
for (FunctionState fs : fns.values()) {
if (fs.canRemove()) {
Function fn = fs.getFn();
Preconditions.checkState(fs.canInline());
Preconditions.checkState(fn != null);
verifyAllReferencesInlined(fs);
fn.remove();
}
}
}
/**
* Sanity check to verify, that expression rewriting didn't
* make a call inaccessible.
*/
void verifyAllReferencesInlined(FunctionState fs) {
for (Reference ref : fs.getReferences()) {
if (!ref.inlined) {
throw new IllegalStateException("Call site missed.\n call: "
+ ref.callNode.toStringTree() + "\n parent: "
+ ref.callNode.getParent().toStringTree());
}
}
}
/**
* Use to track the decisions that have been made about a function.
*/
private static class FunctionState {
private Function fn = null;
private Node safeFnNode = null;
private boolean inline = true;
private boolean remove = true;
private boolean inlineDirectly = false;
private boolean referencesThis = false;
private boolean hasInnerFunctions = false;
private Map<Node, Reference> references = null;
private JSModule module = null;
private Set<String> namesToAlias = null;
boolean hasExistingFunctionDefinition() {
return (fn != null);
}
public void setReferencesThis(boolean referencesThis) {
this.referencesThis = referencesThis;
}
public boolean getReferencesThis() {
return this.referencesThis;
}
public void setHasInnerFunctions(boolean hasInnerFunctions) {
this.hasInnerFunctions = hasInnerFunctions;
}
public boolean hasInnerFunctions() {
return hasInnerFunctions;
}
void removeBlockInliningReferences() {
Iterator<Entry<Node, Reference>> i;
for (i = getReferencesInternal().entrySet().iterator(); i.hasNext();) {
Entry<Node, Reference> entry = i.next();
if (entry.getValue().mode == InliningMode.BLOCK) {
i.remove();
}
}
}
public boolean hasBlockInliningReferences() {
for (Reference r : getReferencesInternal().values()) {
if (r.mode == InliningMode.BLOCK) {
return true;
}
}
return false;
}
public Function getFn() {
return fn;
}
public void setFn(Function fn) {
Preconditions.checkState(this.fn == null);
this.fn = fn;
}
public Node getSafeFnNode() {
return (safeFnNode != null) ? safeFnNode : fn.getFunctionNode();
}
public void setSafeFnNode(Node safeFnNode) {
this.safeFnNode = safeFnNode;
}
public boolean canInline() {
return inline;
}
public void setInline(boolean inline) {
this.inline = inline;
if (!inline) {
// No need to keep references to function that can't be inlined.
references = null;
// Don't remove functions that we aren't inlining.
remove = false;
}
}
public boolean canRemove() {
return remove;
}
public void setRemove(boolean remove) {
this.remove = remove;
}
public boolean canInlineDirectly() {
return inlineDirectly;
}
public void inlineDirectly(boolean directReplacement) {
this.inlineDirectly = directReplacement;
}
public boolean hasReferences() {
return (references != null && !references.isEmpty());
}
private Map<Node, Reference> getReferencesInternal() {
if (references == null) {
return Collections.emptyMap();
}
return references;
}
public void addReference(Reference ref) {
if (references == null) {
references = new LinkedHashMap<>();
}
references.put(ref.callNode, ref);
}
public Collection<Reference> getReferences() {
return getReferencesInternal().values();
}
public Reference getReference(Node n) {
return getReferencesInternal().get(n);
}
public Set<String> getNamesToAlias() {
if (namesToAlias == null) {
return Collections.emptySet();
}
return Collections.unmodifiableSet(namesToAlias);
}
public void setNamesToAlias(Set<String> names) {
namesToAlias = names;
}
public void setModule(JSModule module) {
this.module = module;
}
public JSModule getModule() {
return module;
}
}
/**
* Interface for dealing with function declarations and function
* expressions equally
*/
private static interface Function {
/** Gets the name of the function */
public String getName();
/** Gets the function node */
public Node getFunctionNode();
/** Removes itself from the JavaScript */
public void remove();
public Node getDeclaringBlock();
}
/** NamedFunction implementation of the Function interface */
private class NamedFunction implements Function {
private final Node fn;
public NamedFunction(Node fn) {
this.fn = fn;
}
@Override
public String getName() {
return fn.getFirstChild().getString();
}
@Override
public Node getFunctionNode() {
return fn;
}
@Override
public void remove() {
compiler.reportChangeToEnclosingScope(fn);
NodeUtil.removeChild(fn.getParent(), fn);
}
@Override
public Node getDeclaringBlock() {
return fn.getParent();
}
}
/** FunctionVar implementation of the Function interface */
private class FunctionVar implements Function {
private final Node var;
public FunctionVar(Node var) {
this.var = var;
}
@Override
public String getName() {
return var.getFirstChild().getString();
}
@Override
public Node getFunctionNode() {
return var.getFirstFirstChild();
}
@Override
public void remove() {
compiler.reportChangeToEnclosingScope(var);
NodeUtil.removeChild(var.getParent(), var);
}
@Override
public Node getDeclaringBlock() {
return var.getParent();
}
}
/** FunctionExpression implementation of the Function interface */
private static class FunctionExpression implements Function {
private final Node fn;
private final String fakeName;
public FunctionExpression(Node fn, int index) {
this.fn = fn;
// A number is not a valid function JavaScript identifier
// so we don't need to worry about collisions.
this.fakeName = String.valueOf(index);
}
@Override
public String getName() {
return fakeName;
}
@Override
public Node getFunctionNode() {
return fn;
}
@Override
public void remove() {
// Nothing to do. The function is removed with the call.
}
@Override
public Node getDeclaringBlock() {
return null;
}
}
static class Reference extends FunctionInjector.Reference {
boolean requiresDecomposition = false;
boolean inlined = false;
Reference(
Node callNode, Scope scope, JSModule module,
InliningMode mode) {
super(callNode, scope, module, mode);
}
void setRequiresDecomposition(boolean newVal) {
this.requiresDecomposition = newVal;
}
}
}