@Override
public void visit(NodeTraversal t, Node n, Node parent) {
if ((t.inGlobalScope() && inlineGlobalFunctions)
|| (!t.inGlobalScope() && inlineLocalFunctions)) {
findNamedFunctions(t, n, parent);
findFunctionExpressions(t, n);
}
}
public void enterScope(NodeTraversal t) {
if (t.inGlobalScope()) {
scopes.push(typeSystem.getRootScope());
} else {
scopes.push(typeSystem.getFunctionScope(t.getScopeRoot()));
}
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
if (n.isString() && !parent.isGetProp() && !parent.isRegExp()) {
String str = n.getString();
// "undefined" is special-cased, since it needs to be used when JS code
// is unloading and therefore variable references aren't available.
// This is because of a bug in Firefox.
if ("undefined".equals(str)) {
return;
}
if (blacklist != null && blacklist.reset(str).find()) {
return;
}
if (aliasableStrings == null || aliasableStrings.contains(str)) {
StringOccurrence occurrence = new StringOccurrence(n, parent);
StringInfo info = getOrCreateStringInfo(str);
info.occurrences.add(occurrence);
info.numOccurrences++;
if (t.inGlobalScope() || isInThrowExpression(n)) {
info.numOccurrencesInfrequentlyExecuted++;
}
// The current module.
JSModule module = t.getModule();
if (info.numOccurrences != 1) {
// Check whether the current module depends on the module containing
// the declaration.
if (module != null
&& info.moduleToContainDecl != null
&& module != info.moduleToContainDecl
&& !moduleGraph.dependsOn(module, info.moduleToContainDecl)) {
// We need to declare this string in the deepest module in the
// module dependency graph that both of these modules depend on.
module = moduleGraph.getDeepestCommonDependency(module, info.moduleToContainDecl);
} else {
// use the previously saved insertion location.
return;
}
}
Node varParent = moduleVarParentMap.get(module);
if (varParent == null) {
varParent = compiler.getNodeForCodeInsertion(module);
moduleVarParentMap.put(module, varParent);
}
info.moduleToContainDecl = module;
info.parentForNewVarDecl = varParent;
info.siblingToInsertVarDeclBefore = varParent.getFirstChild();
}
}
}
@Override
public void enterScope(NodeTraversal t) {
if (t.inGlobalScope()) return;
Iterator<Var> it = t.getScope().getVars();
while (it.hasNext()) {
Var current = it.next();
if (current.isBleedingFunction()) {
localBleedingFunctions.add(current);
localBleedingFunctionsPerScope.put(t.getScope().getParent(), current);
}
}
}
/**
* Determines whether a function can be inlined at a particular call site. - Don't inline if the
* calling function contains an inner function and inlining would introduce new globals.
*/
private boolean callMeetsBlockInliningRequirements(
NodeTraversal t, Node callNode, Node fnNode, Set<String> namesToAlias) {
// Note: functions that contain function definitions are filtered out
// in isCanidateFunction.
// TODO(johnlenz): Determining if the called function contains VARs
// or if the caller contains inner functions accounts for 20% of the
// runtime cost of this pass.
// Don't inline functions with var declarations into a scope with inner
// functions as the new vars would leak into the inner function and
// cause memory leaks.
boolean fnContainsVars =
NodeUtil.has(
NodeUtil.getFunctionBody(fnNode),
new NodeUtil.MatchDeclaration(),
new NodeUtil.MatchShallowStatement());
boolean callerContainsFunction = false;
if (!t.inGlobalScope()) {
Node fnCaller = t.getScopeRoot();
Node fnCallerBody = fnCaller.getLastChild();
callerContainsFunction = NodeUtil.containsFunction(fnCallerBody);
}
if (fnContainsVars && callerContainsFunction) {
return false;
}
// If the caller contains functions, verify we aren't adding any
// additional VAR declarations because aliasing is needed.
if (callerContainsFunction) {
Map<String, Node> args =
FunctionArgumentInjector.getFunctionCallParameterMap(
fnNode, callNode, this.safeNameIdSupplier);
boolean hasArgs = !args.isEmpty();
if (hasArgs) {
// Limit the inlining
Set<String> allNamesToAlias = Sets.newHashSet(namesToAlias);
FunctionArgumentInjector.maybeAddTempsForCallArguments(
fnNode, args, allNamesToAlias, compiler.getCodingConvention());
if (!allNamesToAlias.isEmpty()) {
return false;
}
}
}
return true;
}
/**
* @param t The traversal use to reach the call site.
* @param callNode The CALL node.
* @param fnNode The function to evaluate for inlining.
* @param needAliases A set of function parameter names that can not be used without aliasing.
* Returned by getUnsafeParameterNames().
* @param mode Inlining mode to be used.
* @param referencesThis Whether fnNode contains references to its this object.
* @param containsFunctions Whether fnNode contains inner functions.
* @return Whether the inlining can occur.
*/
CanInlineResult canInlineReferenceToFunction(
NodeTraversal t,
Node callNode,
Node fnNode,
Set<String> needAliases,
InliningMode mode,
boolean referencesThis,
boolean containsFunctions) {
// TODO(johnlenz): This function takes too many parameter, without
// context. Modify the API to take a structure describing the function.
// Allow direct function calls or "fn.call" style calls.
if (!isSupportedCallType(callNode)) {
return CanInlineResult.NO;
}
// Limit where functions that contain functions can be inline. Introducing
// an inner function into another function can capture a variable and cause
// a memory leak. This isn't a problem in the global scope as those values
// last until explicitly cleared.
if (containsFunctions && !t.inGlobalScope()) {
// TODO(johnlenz): Allow inlining into any scope without local names or
// inner functions.
return CanInlineResult.NO;
}
// TODO(johnlenz): Add support for 'apply'
if (referencesThis && !NodeUtil.isFunctionObjectCall(callNode)) {
// TODO(johnlenz): Allow 'this' references to be replaced with a
// global 'this' object.
return CanInlineResult.NO;
}
if (mode == InliningMode.DIRECT) {
return canInlineReferenceDirectly(callNode, fnNode);
} else {
return canInlineReferenceAsStatementBlock(t, callNode, fnNode, needAliases);
}
}
/** Returns the function the traversal is currently traversing, or null if in the global scope. */
private static Node getContainingFunction(NodeTraversal t) {
return (t.inGlobalScope()) ? null : t.getScopeRoot();
}
@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.inGlobalScope();
}
@SuppressWarnings("incomplete-switch")
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
if (!n.isCall()) {
return;
}
String callName = n.getFirstChild().getQualifiedName();
TweakFunction tweakFunc = TWEAK_FUNCTIONS_MAP.get(callName);
if (tweakFunc == null) {
return;
}
if (tweakFunc == TweakFunction.GET_COMPILER_OVERRIDES) {
getOverridesCalls.add(new TweakFunctionCall(tweakFunc, n));
return;
}
// Ensure the first parameter (the tweak ID) is a string literal.
Node tweakIdNode = n.getFirstChild().getNext();
if (!tweakIdNode.isString()) {
compiler.report(t.makeError(tweakIdNode, NON_LITERAL_TWEAK_ID_ERROR));
return;
}
String tweakId = tweakIdNode.getString();
// Make sure there is a TweakInfo structure for it.
TweakInfo tweakInfo = allTweaks.get(tweakId);
if (tweakInfo == null) {
tweakInfo = new TweakInfo(tweakId);
allTweaks.put(tweakId, tweakInfo);
}
switch (tweakFunc) {
case REGISTER_BOOLEAN:
case REGISTER_NUMBER:
case REGISTER_STRING:
// Ensure the ID contains only valid characters.
if (!ID_MATCHER.matchesAllOf(tweakId)) {
compiler.report(t.makeError(tweakIdNode, INVALID_TWEAK_ID_ERROR));
}
// Ensure tweaks are registered in the global scope.
if (!t.inGlobalScope()) {
compiler.report(t.makeError(n, NON_GLOBAL_TWEAK_INIT_ERROR, tweakId));
break;
}
// Ensure tweaks are registered only once.
if (tweakInfo.isRegistered()) {
compiler.report(t.makeError(n, TWEAK_MULTIPLY_REGISTERED_ERROR, tweakId));
break;
}
Node tweakDefaultValueNode = tweakIdNode.getNext().getNext();
tweakInfo.addRegisterCall(t.getSourceName(), tweakFunc, n, tweakDefaultValueNode);
break;
case OVERRIDE_DEFAULT_VALUE:
// Ensure tweaks overrides occur in the global scope.
if (!t.inGlobalScope()) {
compiler.report(t.makeError(n, NON_GLOBAL_TWEAK_INIT_ERROR, tweakId));
break;
}
// Ensure tweak overrides occur before the tweak is registered.
if (tweakInfo.isRegistered()) {
compiler.report(t.makeError(n, TWEAK_OVERRIDE_AFTER_REGISTERED_ERROR, tweakId));
break;
}
tweakDefaultValueNode = tweakIdNode.getNext();
tweakInfo.addOverrideDefaultValueCall(
t.getSourceName(), tweakFunc, n, tweakDefaultValueNode);
break;
case GET_BOOLEAN:
case GET_NUMBER:
case GET_STRING:
tweakInfo.addGetterCall(t.getSourceName(), tweakFunc, n);
}
}