Avoid an extra stat() on the source .qml file when loading cache

For timestamp comparison it is not necessary to create another
QFileInfo() object and call exists() and lastModified(), when we can
pass that information through from the type loader.

Change-Id: I225cd36e672f1f390bddb4e6ebfafa3fc1269795
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

8 files changed, 14 insertions, 18 deletions

diff --git a/src/qml/compiler/qv4compilationunitmapper.cpp b/src/qml/compiler/qv4compilationunitmapper.cpp
index 1ae0fb190c..d94f7ac238 100644
--- a/src/qml/compiler/qv4compilationunitmapper.cpp
+++ b/src/qml/compiler/qv4compilationunitmapper.cpp
@@ -59,7 +59,7 @@ CompilationUnitMapper::~CompilationUnitMapper()
     close();
 }
 
-bool CompilationUnitMapper::verifyHeader(const CompiledData::Unit *header, const QString &sourcePath, QString *errorString)
+bool CompilationUnitMapper::verifyHeader(const CompiledData::Unit *header, QDateTime sourceTimeStamp, QString *errorString)
 {
     if (strncmp(header->magic, CompiledData::magic_str, sizeof(header->magic))) {
         *errorString = QStringLiteral("Magic bytes in the header do not match");
@@ -77,11 +77,6 @@ bool CompilationUnitMapper::verifyHeader(const CompiledData::Unit *header, const
     }
 
     if (header->sourceTimeStamp) {
-        QFileInfo sourceCode(sourcePath);
-        QDateTime sourceTimeStamp;
-        if (sourceCode.exists())
-            sourceTimeStamp = sourceCode.lastModified();
-
         // Files from the resource system do not have any time stamps, so fall back to the application
         // executable.
         if (!sourceTimeStamp.isValid())
diff --git a/src/qml/compiler/qv4compilationunitmapper_p.h b/src/qml/compiler/qv4compilationunitmapper_p.h
index 5b6939f1cf..b24f98df7c 100644
--- a/src/qml/compiler/qv4compilationunitmapper_p.h
+++ b/src/qml/compiler/qv4compilationunitmapper_p.h
@@ -68,11 +68,11 @@ public:
     CompilationUnitMapper();
     ~CompilationUnitMapper();
 
-    CompiledData::Unit *open(const QString &cacheFilePath, const QString &sourcePath, QString *errorString);
+    CompiledData::Unit *open(const QString &cacheFilePath, const QDateTime &sourceTimeStamp, QString *errorString);
     void close();
 
 private:
-    static bool verifyHeader(const QV4::CompiledData::Unit *header, const QString &sourcePath, QString *errorString);
+    static bool verifyHeader(const QV4::CompiledData::Unit *header, QDateTime sourceTimeStamp, QString *errorString);
 
 #if defined(Q_OS_UNIX)
     size_t length;
diff --git a/src/qml/compiler/qv4compilationunitmapper_unix.cpp b/src/qml/compiler/qv4compilationunitmapper_unix.cpp
index 1aa3e05f5f..38dabc41cf 100644
--- a/src/qml/compiler/qv4compilationunitmapper_unix.cpp
+++ b/src/qml/compiler/qv4compilationunitmapper_unix.cpp
@@ -43,6 +43,7 @@
 #include <functional>
 #include <private/qcore_unix_p.h>
 #include <private/qdeferredcleanup_p.h>
+#include <QDateTime>
 
 #include "qv4compileddata_p.h"
 
@@ -50,7 +51,7 @@ QT_BEGIN_NAMESPACE
 
 using namespace QV4;
 
-CompiledData::Unit *CompilationUnitMapper::open(const QString &cacheFileName, const QString &sourcePath, QString *errorString)
+CompiledData::Unit *CompilationUnitMapper::open(const QString &cacheFileName, const QDateTime &sourceTimeStamp, QString *errorString)
 {
     close();
 
@@ -72,7 +73,7 @@ CompiledData::Unit *CompilationUnitMapper::open(const QString &cacheFileName, co
         return nullptr;
     }
 
-    if (!verifyHeader(&header, sourcePath, errorString))
+    if (!verifyHeader(&header, sourceTimeStamp, errorString))
         return nullptr;
 
     // Data structure and qt version matched, so now we can access the rest of the file safely.
diff --git a/src/qml/compiler/qv4compilationunitmapper_win.cpp b/src/qml/compiler/qv4compilationunitmapper_win.cpp
index 37cac846a0..d7a93ae233 100644
--- a/src/qml/compiler/qv4compilationunitmapper_win.cpp
+++ b/src/qml/compiler/qv4compilationunitmapper_win.cpp
@@ -49,7 +49,7 @@ QT_BEGIN_NAMESPACE
 
 using namespace QV4;
 
-CompiledData::Unit *CompilationUnitMapper::open(const QString &cacheFileName, const QString &sourcePath, QString *errorString)
+CompiledData::Unit *CompilationUnitMapper::open(const QString &cacheFileName, const QDateTime &sourceTimeStamp, QString *errorString)
 {
     close();
 
@@ -87,7 +87,7 @@ CompiledData::Unit *CompilationUnitMapper::open(const QString &cacheFileName, co
         return nullptr;
     }
 
-    if (!verifyHeader(&header, sourcePath, errorString))
+    if (!verifyHeader(&header, sourceTimeStamp, errorString))
         return nullptr;
 
     const uint mappingFlags = header.flags & QV4::CompiledData::Unit::ContainsMachineCode
diff --git a/src/qml/compiler/qv4compileddata.cpp b/src/qml/compiler/qv4compileddata.cpp
index 4688f936cc..1805ab3f54 100644
--- a/src/qml/compiler/qv4compileddata.cpp
+++ b/src/qml/compiler/qv4compileddata.cpp
@@ -343,7 +343,7 @@ bool CompilationUnit::verifyChecksum(QQmlEngine *engine,
                   sizeof(data->dependencyMD5Checksum)) == 0;
 }
 
-bool CompilationUnit::loadFromDisk(const QUrl &url, EvalISelFactory *iselFactory, QString *errorString)
+bool CompilationUnit::loadFromDisk(const QUrl &url, const QDateTime &sourceTimeStamp, EvalISelFactory *iselFactory, QString *errorString)
 {
     if (!QQmlFile::isLocalFile(url)) {
         *errorString = QStringLiteral("File has to be a local file.");
@@ -353,7 +353,7 @@ bool CompilationUnit::loadFromDisk(const QUrl &url, EvalISelFactory *iselFactory
     const QString sourcePath = QQmlFile::urlToLocalFileOrQrc(url);
     QScopedPointer<CompilationUnitMapper> cacheFile(new CompilationUnitMapper());
 
-    CompiledData::Unit *mappedUnit = cacheFile->open(cacheFilePath(url), sourcePath, errorString);
+    CompiledData::Unit *mappedUnit = cacheFile->open(cacheFilePath(url), sourceTimeStamp, errorString);
     if (!mappedUnit)
         return false;
 
diff --git a/src/qml/compiler/qv4compileddata_p.h b/src/qml/compiler/qv4compileddata_p.h
index 6d219b85aa..8cf5437928 100644
--- a/src/qml/compiler/qv4compileddata_p.h
+++ b/src/qml/compiler/qv4compileddata_p.h
@@ -899,7 +899,7 @@ struct Q_QML_PRIVATE_EXPORT CompilationUnit : public CompilationUnitBase, public
 
     void destroy() Q_DECL_OVERRIDE;
 
-    bool loadFromDisk(const QUrl &url, EvalISelFactory *iselFactory, QString *errorString);
+    bool loadFromDisk(const QUrl &url, const QDateTime &sourceTimeStamp, EvalISelFactory *iselFactory, QString *errorString);
 
 protected:
     virtual void linkBackendToEngine(QV4::ExecutionEngine *engine) = 0;
diff --git a/src/qml/compiler/qv4compiler.cpp b/src/qml/compiler/qv4compiler.cpp
index 9cfac4a676..64f034ddcb 100644
--- a/src/qml/compiler/qv4compiler.cpp
+++ b/src/qml/compiler/qv4compiler.cpp
@@ -425,7 +425,7 @@ QV4::CompiledData::Unit QV4::Compiler::JSUnitGenerator::generateHeader(QV4::Comp
     }
     unit.indexOfRootFunction = -1;
     unit.sourceFileIndex = getStringId(irModule->fileName);
-    unit.sourceTimeStamp = irModule->sourceTimeStamp;
+    unit.sourceTimeStamp = irModule->sourceTimeStamp.isValid() ? irModule->sourceTimeStamp.toMSecsSinceEpoch() : 0;
     unit.nImports = 0;
     unit.offsetToImports = 0;
     unit.nObjects = 0;
diff --git a/src/qml/compiler/qv4jsir_p.h b/src/qml/compiler/qv4jsir_p.h
index 23ebe0c962..d9192c1a3b 100644
--- a/src/qml/compiler/qv4jsir_p.h
+++ b/src/qml/compiler/qv4jsir_p.h
@@ -61,6 +61,7 @@
 #include <QtCore/QBitArray>
 #include <QtCore/qurl.h>
 #include <QtCore/QVarLengthArray>
+#include <QtCore/QDateTime>
 #include <qglobal.h>
 
 #if defined(CONST) && defined(Q_OS_WIN)
@@ -942,7 +943,7 @@ struct Q_QML_PRIVATE_EXPORT Module {
     QVector<Function *> functions;
     Function *rootFunction;
     QString fileName;
-    qint64 sourceTimeStamp;
+    QDateTime sourceTimeStamp;
     bool isQmlModule; // implies rootFunction is always 0
     uint unitFlags; // flags merged into CompiledData::Unit::flags
 #ifdef QT_NO_QML_DEBUGGER
@@ -955,7 +956,6 @@ struct Q_QML_PRIVATE_EXPORT Module {
 
     Module(bool debugMode)
         : rootFunction(0)
-        , sourceTimeStamp(0)
         , isQmlModule(false)
         , unitFlags(0)
 #ifndef QT_NO_QML_DEBUGGER