Clean up type dependency hashing for QML caching

Instead of passing the engine parameter all the way through the data
structure generator, along with the dependent type data structure that
is unused otherwise, let's simply provide a function object for the
dependency hashing.

This is also in preparation for adding singleton types to the dependency
hash.

Task-number: QTBUG-58486
Change-Id: I5bb5e5c06b7b5c77195cec3da13141333cfea7a8
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

8 files changed, 29 insertions, 23 deletions

diff --git a/src/qml/compiler/qqmlirbuilder.cpp b/src/qml/compiler/qqmlirbuilder.cpp
index c0f953ca2c..8ead1c9b5d 100644
--- a/src/qml/compiler/qqmlirbuilder.cpp
+++ b/src/qml/compiler/qqmlirbuilder.cpp
@@ -1359,7 +1359,7 @@ bool IRBuilder::isRedundantNullInitializerForPropertyDeclaration(Property *prope
     return QQmlJS::AST::cast<QQmlJS::AST::NullExpression *>(expr);
 }
 
-QV4::CompiledData::Unit *QmlUnitGenerator::generate(Document &output, QQmlEngine *engine, const QV4::CompiledData::ResolvedTypeReferenceMap &dependentTypes)
+QV4::CompiledData::Unit *QmlUnitGenerator::generate(Document &output, const QV4::CompiledData::DependentTypesHasher &dependencyHasher)
 {
     QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit = output.javaScriptCompilationUnit;
     QV4::CompiledData::Unit *jsUnit = compilationUnit->createUnitData(&output);
@@ -1402,17 +1402,16 @@ QV4::CompiledData::Unit *QmlUnitGenerator::generate(Document &output, QQmlEngine
     qmlUnit->stringTableSize = output.jsGenerator.stringTable.stringCount();
 
 #ifndef V4_BOOTSTRAP
-    if (!dependentTypes.isEmpty()) {
+    if (dependencyHasher) {
         QCryptographicHash hash(QCryptographicHash::Md5);
-        if (dependentTypes.addToHash(&hash, engine)) {
+        if (dependencyHasher(&hash)) {
             QByteArray checksum = hash.result();
             Q_ASSERT(checksum.size() == sizeof(qmlUnit->dependencyMD5Checksum));
             memcpy(qmlUnit->dependencyMD5Checksum, checksum.constData(), sizeof(qmlUnit->dependencyMD5Checksum));
         }
     }
 #else
-    Q_UNUSED(dependentTypes);
-    Q_UNUSED(engine);
+    Q_UNUSED(dependencyHasher);
 #endif
 
     // write imports
diff --git a/src/qml/compiler/qqmlirbuilder_p.h b/src/qml/compiler/qqmlirbuilder_p.h
index cc16dc2104..44f8cef16a 100644
--- a/src/qml/compiler/qqmlirbuilder_p.h
+++ b/src/qml/compiler/qqmlirbuilder_p.h
@@ -548,7 +548,7 @@ public:
 
 struct Q_QML_PRIVATE_EXPORT QmlUnitGenerator
 {
-    QV4::CompiledData::Unit *generate(Document &output, QQmlEngine *engine, const QV4::CompiledData::ResolvedTypeReferenceMap &dependentTypes);
+    QV4::CompiledData::Unit *generate(Document &output, const QV4::CompiledData::DependentTypesHasher &dependencyHasher = QV4::CompiledData::DependentTypesHasher());
 
 private:
     typedef bool (Binding::*BindingFilter)() const;
diff --git a/src/qml/compiler/qqmltypecompiler.cpp b/src/qml/compiler/qqmltypecompiler.cpp
index b7262e4333..0f3ebac223 100644
--- a/src/qml/compiler/qqmltypecompiler.cpp
+++ b/src/qml/compiler/qqmltypecompiler.cpp
@@ -58,10 +58,11 @@ QT_BEGIN_NAMESPACE
 
 QQmlTypeCompiler::QQmlTypeCompiler(QQmlEnginePrivate *engine, QQmlTypeData *typeData,
                                    QmlIR::Document *parsedQML, const QQmlRefPointer<QQmlTypeNameCache> &importCache,
-                                   const QV4::CompiledData::ResolvedTypeReferenceMap &resolvedTypeCache)
+                                   const QV4::CompiledData::ResolvedTypeReferenceMap &resolvedTypeCache, const QV4::CompiledData::DependentTypesHasher &dependencyHasher)
     : resolvedTypes(resolvedTypeCache)
     , engine(engine)
     , typeData(typeData)
+    , dependencyHasher(dependencyHasher)
     , importCache(importCache)
     , document(parsedQML)
 {
@@ -156,7 +157,7 @@ QV4::CompiledData::CompilationUnit *QQmlTypeCompiler::compile()
     // Generate QML compiled type data structures
 
     QmlIR::QmlUnitGenerator qmlGenerator;
-    QV4::CompiledData::Unit *qmlUnit = qmlGenerator.generate(*document, QQmlEnginePrivate::get(engine), resolvedTypes);
+    QV4::CompiledData::Unit *qmlUnit = qmlGenerator.generate(*document, dependencyHasher);
 
     Q_ASSERT(document->javaScriptCompilationUnit);
     // The js unit owns the data and will free the qml unit.
diff --git a/src/qml/compiler/qqmltypecompiler_p.h b/src/qml/compiler/qqmltypecompiler_p.h
index de6abb4ced..7df4fb57cb 100644
--- a/src/qml/compiler/qqmltypecompiler_p.h
+++ b/src/qml/compiler/qqmltypecompiler_p.h
@@ -89,7 +89,8 @@ struct QQmlTypeCompiler
 {
     Q_DECLARE_TR_FUNCTIONS(QQmlTypeCompiler)
 public:
-    QQmlTypeCompiler(QQmlEnginePrivate *engine, QQmlTypeData *typeData, QmlIR::Document *document, const QQmlRefPointer<QQmlTypeNameCache> &importCache, const QV4::CompiledData::ResolvedTypeReferenceMap &resolvedTypeCache);
+    QQmlTypeCompiler(QQmlEnginePrivate *engine, QQmlTypeData *typeData, QmlIR::Document *document, const QQmlRefPointer<QQmlTypeNameCache> &importCache, const QV4::CompiledData::ResolvedTypeReferenceMap &resolvedTypeCache,
+                     const QV4::CompiledData::DependentTypesHasher &dependencyHasher);
 
     // --- interface used by QQmlPropertyCacheCreator
     typedef QmlIR::Object CompiledObject;
@@ -139,6 +140,7 @@ private:
     QList<QQmlError> errors;
     QQmlEnginePrivate *engine;
     QQmlTypeData *typeData;
+    const QV4::CompiledData::DependentTypesHasher &dependencyHasher;
     QQmlRefPointer<QQmlTypeNameCache> importCache;
     QmlIR::Document *document;
     // index is string index of type name (use obj->inheritedTypeNameIndex)
diff --git a/src/qml/compiler/qv4compileddata.cpp b/src/qml/compiler/qv4compileddata.cpp
index d8ff22e9ed..b175abe1f5 100644
--- a/src/qml/compiler/qv4compileddata.cpp
+++ b/src/qml/compiler/qv4compileddata.cpp
@@ -310,10 +310,9 @@ void CompilationUnit::finalize(QQmlEnginePrivate *engine)
     totalObjectCount = objectCount;
 }
 
-bool CompilationUnit::verifyChecksum(QQmlEngine *engine,
-                                     const ResolvedTypeReferenceMap &dependentTypes) const
+bool CompilationUnit::verifyChecksum(const DependentTypesHasher &dependencyHasher) const
 {
-    if (dependentTypes.isEmpty()) {
+    if (!dependencyHasher) {
         for (size_t i = 0; i < sizeof(data->dependencyMD5Checksum); ++i) {
             if (data->dependencyMD5Checksum[i] != 0)
                 return false;
@@ -321,7 +320,7 @@ bool CompilationUnit::verifyChecksum(QQmlEngine *engine,
         return true;
     }
     QCryptographicHash hash(QCryptographicHash::Md5);
-    if (!dependentTypes.addToHash(&hash, engine))
+    if (!dependencyHasher(&hash))
         return false;
     QByteArray checksum = hash.result();
     Q_ASSERT(checksum.size() == sizeof(data->dependencyMD5Checksum));
diff --git a/src/qml/compiler/qv4compileddata_p.h b/src/qml/compiler/qv4compileddata_p.h
index 2682365182..cb8ce8a649 100644
--- a/src/qml/compiler/qv4compileddata_p.h
+++ b/src/qml/compiler/qv4compileddata_p.h
@@ -809,8 +809,10 @@ struct ResolvedTypeReferenceMap: public QMap<int, ResolvedTypeReference*>
 {
     bool addToHash(QCryptographicHash *hash, QQmlEngine *engine) const;
 };
+
+using DependentTypesHasher = std::function<bool(QCryptographicHash *)>;
 #else
-struct ResolvedTypeReferenceMap {};
+struct DependentTypesHasher {};
 #endif
 
 // index is per-object binding index
@@ -879,8 +881,7 @@ struct Q_QML_PRIVATE_EXPORT CompilationUnit : public QQmlRefCount
     QVector<QQmlScriptData *> dependentScripts;
     ResolvedTypeReferenceMap resolvedTypes;
 
-    bool verifyChecksum(QQmlEngine *engine,
-                        const ResolvedTypeReferenceMap &dependentTypes) const;
+    bool verifyChecksum(const DependentTypesHasher &dependencyHasher) const;
 
     int metaTypeId;
     int listMetaTypeId;
diff --git a/src/qml/qml/qqmltypeloader.cpp b/src/qml/qml/qqmltypeloader.cpp
index 7ad18c8efb..dea8f3ed6f 100644
--- a/src/qml/qml/qqmltypeloader.cpp
+++ b/src/qml/qml/qqmltypeloader.cpp
@@ -2227,8 +2227,12 @@ void QQmlTypeData::done()
 
     QQmlEngine *const engine = typeLoader()->engine();
 
+    const auto dependencyHasher = [engine, resolvedTypeCache](QCryptographicHash *hash) {
+        return resolvedTypeCache.addToHash(hash, engine);
+    };
+
     // verify if any dependencies changed if we're using a cache
-    if (m_document.isNull() && !m_compiledData->verifyChecksum(engine, resolvedTypeCache)) {
+    if (m_document.isNull() && !m_compiledData->verifyChecksum(dependencyHasher)) {
         qCDebug(DBG_DISK_CACHE) << "Checksum mismatch for cached version of" << m_compiledData->url().toString();
         if (!loadFromSource())
             return;
@@ -2238,7 +2242,7 @@ void QQmlTypeData::done()
 
     if (!m_document.isNull()) {
         // Compile component
-        compile(importCache, resolvedTypeCache);
+        compile(importCache, resolvedTypeCache, dependencyHasher);
     } else {
         createTypeAndPropertyCaches(importCache, resolvedTypeCache);
     }
@@ -2487,12 +2491,13 @@ QString QQmlTypeData::stringAt(int index) const
     return m_document->jsGenerator.stringTable.stringForIndex(index);
 }
 
-void QQmlTypeData::compile(const QQmlRefPointer<QQmlTypeNameCache> &importCache, const QV4::CompiledData::ResolvedTypeReferenceMap &resolvedTypeCache)
+void QQmlTypeData::compile(const QQmlRefPointer<QQmlTypeNameCache> &importCache, const QV4::CompiledData::ResolvedTypeReferenceMap &resolvedTypeCache,
+                           const QV4::CompiledData::DependentTypesHasher &dependencyHasher)
 {
     Q_ASSERT(m_compiledData.isNull());
 
     QQmlEnginePrivate * const enginePrivate = QQmlEnginePrivate::get(typeLoader()->engine());
-    QQmlTypeCompiler compiler(enginePrivate, this, m_document.data(), importCache, resolvedTypeCache);
+    QQmlTypeCompiler compiler(enginePrivate, this, m_document.data(), importCache, resolvedTypeCache, dependencyHasher);
     m_compiledData = compiler.compile();
     if (!m_compiledData) {
         setError(compiler.compilationErrors());
@@ -2934,8 +2939,7 @@ void QQmlScriptBlob::dataReceived(const Data &data)
         irUnit.jsModule.unitFlags |= QV4::CompiledData::Unit::IsSharedLibrary;
 
     QmlIR::QmlUnitGenerator qmlGenerator;
-    QV4::CompiledData::ResolvedTypeReferenceMap emptyDependencies;
-    QV4::CompiledData::Unit *unitData = qmlGenerator.generate(irUnit, m_typeLoader->engine(), emptyDependencies);
+    QV4::CompiledData::Unit *unitData = qmlGenerator.generate(irUnit);
     Q_ASSERT(!unit->data);
     // The js unit owns the data and will free the qml unit.
     unit->data = unitData;
diff --git a/src/qml/qml/qqmltypeloader_p.h b/src/qml/qml/qqmltypeloader_p.h
index 53cf4234e1..d85346c23e 100644
--- a/src/qml/qml/qqmltypeloader_p.h
+++ b/src/qml/qml/qqmltypeloader_p.h
@@ -453,7 +453,7 @@ private:
             QV4::CompiledData::ResolvedTypeReferenceMap *resolvedTypeCache
             ) const;
     void compile(const QQmlRefPointer<QQmlTypeNameCache> &importCache,
-                 const QV4::CompiledData::ResolvedTypeReferenceMap &resolvedTypeCache);
+                 const QV4::CompiledData::ResolvedTypeReferenceMap &resolvedTypeCache, const QV4::CompiledData::DependentTypesHasher &dependencyHasher);
     void createTypeAndPropertyCaches(const QQmlRefPointer<QQmlTypeNameCache> &importCache,
                                       const QV4::CompiledData::ResolvedTypeReferenceMap &resolvedTypeCache);
     bool resolveType(const QString &typeName, int &majorVersion, int &minorVersion, TypeReference &ref);