Use string sharing when serializing file tags

On my machine, the on-disk build graph of a freshly resolved Qt Creator
super project goes down by 12% with this patch.

Change-Id: Ic86b4ba31769d7d4af407b24a0ee9845cf943a79
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>

8 files changed, 61 insertions, 80 deletions

diff --git a/src/lib/corelib/buildgraph/artifact.cpp b/src/lib/corelib/buildgraph/artifact.cpp
index 04a8c97c8..a00d7b623 100644
--- a/src/lib/corelib/buildgraph/artifact.cpp
+++ b/src/lib/corelib/buildgraph/artifact.cpp
@@ -158,9 +158,9 @@ void Artifact::load(PersistentPool &pool)
     pool.loadContainer(fileDependencies);
     properties = pool.idLoadS<PropertyMapInternal>();
     transformer = pool.idLoadS<Transformer>();
+    m_fileTags.load(pool);
     unsigned char c;
     pool.stream()
-            >> m_fileTags
             >> artifactType
             >> c;
     alwaysUpdated = c;
@@ -178,8 +178,8 @@ void Artifact::store(PersistentPool &pool) const
     pool.storeContainer(fileDependencies);
     pool.store(properties);
     pool.store(transformer);
+    m_fileTags.store(pool);
     pool.stream()
-            << m_fileTags
             << artifactType
             << static_cast<unsigned char>(alwaysUpdated)
             << static_cast<unsigned char>(oldDataPossiblyPresent);
diff --git a/src/lib/corelib/buildgraph/productbuilddata.cpp b/src/lib/corelib/buildgraph/productbuilddata.cpp
index d67f667d1..7bd88e577 100644
--- a/src/lib/corelib/buildgraph/productbuilddata.cpp
+++ b/src/lib/corelib/buildgraph/productbuilddata.cpp
@@ -66,8 +66,7 @@ static void loadArtifactSetByFileTag(PersistentPool &pool,
     int elemCount;
     pool.stream() >> elemCount;
     for (int i = 0; i < elemCount; ++i) {
-        QVariant fileTag;
-        pool.stream() >> fileTag;
+        const QVariant fileTag = pool.loadVariant();
         ArtifactSet artifacts;
         pool.loadContainer(artifacts);
         s.insert(FileTag::fromSetting(fileTag), artifacts);
@@ -104,7 +103,7 @@ static void storeArtifactSetByFileTag(PersistentPool &pool,
     pool.stream() << s.count();
     ProductBuildData::ArtifactSetByFileTag::ConstIterator it;
     for (it = s.constBegin(); it != s.constEnd(); ++it) {
-        pool.stream() << it.key().toSetting();
+        pool.store(it.key().toSetting());
         pool.storeContainer(it.value());
     }
 }
diff --git a/src/lib/corelib/buildgraph/rescuableartifactdata.cpp b/src/lib/corelib/buildgraph/rescuableartifactdata.cpp
index 65af1b176..02c3d9ea6 100644
--- a/src/lib/corelib/buildgraph/rescuableartifactdata.cpp
+++ b/src/lib/corelib/buildgraph/rescuableartifactdata.cpp
@@ -69,7 +69,7 @@ void RescuableArtifactData::load(PersistentPool &pool)
     propertiesRequestedInCommands = restorePropertySet(pool);
     propertiesRequestedFromArtifactInPrepareScript = restorePropertyHash(pool);
     commands = loadCommandList(pool);
-    pool.stream() >> fileTags;
+    fileTags.load(pool);
     properties = pool.loadVariantMap();
 }
 
@@ -89,7 +89,7 @@ void RescuableArtifactData::store(PersistentPool &pool) const
     storePropertySet(pool, propertiesRequestedInCommands);
     storePropertyHash(pool, propertiesRequestedFromArtifactInPrepareScript);
     storeCommandList(commands, pool);
-    pool.stream() << fileTags;
+    fileTags.store(pool);
     pool.store(properties);
 }
 
diff --git a/src/lib/corelib/language/artifactproperties.cpp b/src/lib/corelib/language/artifactproperties.cpp
index 6b4bcd00f..eae9fb667 100644
--- a/src/lib/corelib/language/artifactproperties.cpp
+++ b/src/lib/corelib/language/artifactproperties.cpp
@@ -55,13 +55,13 @@ ArtifactProperties::ArtifactProperties()
 
 void ArtifactProperties::load(PersistentPool &pool)
 {
-    pool.stream() >> m_fileTagsFilter;
+    m_fileTagsFilter.load(pool);
     m_propertyMap = pool.idLoadS<PropertyMapInternal>();
 }
 
 void ArtifactProperties::store(PersistentPool &pool) const
 {
-    pool.stream() << m_fileTagsFilter;
+    m_fileTagsFilter.store(pool);
     pool.store(m_propertyMap);
 }
 
diff --git a/src/lib/corelib/language/filetags.cpp b/src/lib/corelib/language/filetags.cpp
index 47b6274a5..c451a24b5 100644
--- a/src/lib/corelib/language/filetags.cpp
+++ b/src/lib/corelib/language/filetags.cpp
@@ -40,6 +40,8 @@
 #include "filetags.h"
 #include <QStringList>
 
+#include <tools/persistence.h>
+
 namespace qbs {
 namespace Internal {
 
@@ -75,6 +77,16 @@ bool FileTags::matches(const FileTags &other) const
     return false;
 }
 
+void FileTags::store(PersistentPool &pool) const
+{
+    pool.storeStringList(toStringList());
+}
+
+void FileTags::load(PersistentPool &pool)
+{
+    *this = fromStringList(pool.idLoadStringList());
+}
+
 LogWriter operator <<(LogWriter w, const FileTags &tags)
 {
     bool firstLoop = true;
@@ -90,27 +102,5 @@ LogWriter operator <<(LogWriter w, const FileTags &tags)
     return w;
 }
 
-QDataStream &operator >>(QDataStream &s, FileTags &tags)
-{
-    int i;
-    s >> i;
-    tags.clear();
-    tags.reserve(i);
-    QVariant v;
-    while (--i >= 0) {
-        s >> v;
-        tags += FileTag::fromSetting(v);
-    }
-    return s;
-}
-
-QDataStream &operator <<(QDataStream &s, const FileTags &tags)
-{
-    s << tags.count();
-    foreach (const FileTag &ft, tags)
-        s << ft.toSetting();
-    return s;
-}
-
 } // namespace Internal
 } // namespace qbs
diff --git a/src/lib/corelib/language/filetags.h b/src/lib/corelib/language/filetags.h
index 8c50d33f1..63e92e44d 100644
--- a/src/lib/corelib/language/filetags.h
+++ b/src/lib/corelib/language/filetags.h
@@ -47,6 +47,7 @@
 
 namespace qbs {
 namespace Internal {
+class PersistentPool;
 
 class FileTag : public Id
 {
@@ -76,11 +77,12 @@ public:
     QStringList toStringList() const;
     static FileTags fromStringList(const QStringList &strings);
     bool matches(const FileTags &other) const;
+
+    void store(PersistentPool &pool) const;
+    void load(PersistentPool &pool);
 };
 
 LogWriter operator <<(LogWriter w, const FileTags &tags);
-QDataStream &operator >>(QDataStream &s, FileTags & tags);
-QDataStream &operator <<(QDataStream &s, const FileTags &tags);
 
 } // namespace Internal
 } // namespace qbs
diff --git a/src/lib/corelib/language/language.cpp b/src/lib/corelib/language/language.cpp
index 47099a0f0..86a8cce5d 100644
--- a/src/lib/corelib/language/language.cpp
+++ b/src/lib/corelib/language/language.cpp
@@ -104,7 +104,7 @@ void FileTagger::setPatterns(const QStringList &patterns)
 void FileTagger::load(PersistentPool &pool)
 {
     setPatterns(pool.idLoadStringList());
-    pool.stream() >> m_fileTags;
+    m_fileTags.load(pool);
 }
 
 void FileTagger::store(PersistentPool &pool) const
@@ -113,7 +113,7 @@ void FileTagger::store(PersistentPool &pool) const
     foreach (const QRegExp &regExp, m_patterns)
         patterns << regExp.pattern();
     pool.storeStringList(patterns);
-    pool.stream() << m_fileTags;
+    m_fileTags.store(pool);
 }
 
 
@@ -148,7 +148,7 @@ void Probe::store(PersistentPool &pool) const
 void SourceArtifactInternal::load(PersistentPool &pool)
 {
     absoluteFilePath = pool.idLoadString();
-    pool.stream() >> fileTags;
+    fileTags.load(pool);
     pool.stream() >> overrideFileTags;
     properties = pool.idLoadS<PropertyMapInternal>();
 }
@@ -156,7 +156,7 @@ void SourceArtifactInternal::load(PersistentPool &pool)
 void SourceArtifactInternal::store(PersistentPool &pool) const
 {
     pool.storeString(absoluteFilePath);
-    pool.stream() << fileTags;
+    fileTags.store(pool);
     pool.stream() << overrideFileTags;
     pool.store(properties);
 }
@@ -216,9 +216,8 @@ void ResolvedGroup::load(PersistentPool &pool)
     pool.loadContainerS(files);
     wildcards = pool.idLoadS<SourceWildCards>();
     properties = pool.idLoadS<PropertyMapInternal>();
-    pool.stream()
-            >> fileTags
-            >> overrideTags;
+    fileTags.load(pool);
+    pool.stream() >> overrideTags;
 }
 
 void ResolvedGroup::store(PersistentPool &pool) const
@@ -230,9 +229,8 @@ void ResolvedGroup::store(PersistentPool &pool) const
     pool.storeContainer(files);
     pool.store(wildcards);
     pool.store(properties);
-    pool.stream()
-            << fileTags
-            << overrideTags;
+    fileTags.store(pool);
+    pool.stream() << overrideTags;
 }
 
 /*!
@@ -246,10 +244,9 @@ void ResolvedGroup::store(PersistentPool &pool) const
  */
 void RuleArtifact::load(PersistentPool &pool)
 {
-    pool.stream()
-            >> filePath
-            >> fileTags
-            >> alwaysUpdated;
+    filePath = pool.idLoadString();
+    fileTags.load(pool);
+    pool.stream() >> alwaysUpdated;
     location.load(pool);
     filePathLocation.load(pool);
 
@@ -268,10 +265,9 @@ void RuleArtifact::load(PersistentPool &pool)
 
 void RuleArtifact::store(PersistentPool &pool) const
 {
-    pool.stream()
-            << filePath
-            << fileTags
-            << alwaysUpdated;
+    pool.storeString(filePath);
+    fileTags.store(pool);
+    pool.stream() << alwaysUpdated;
     location.store(pool);
     filePathLocation.store(pool);
 
@@ -413,16 +409,13 @@ void Rule::load(PersistentPool &pool)
     prepareScript = pool.idLoadS<ScriptFunction>();
     outputArtifactsScript = pool.idLoadS<ScriptFunction>();
     module = pool.idLoadS<ResolvedModule>();
-    pool.stream()
-        >> inputs
-        >> outputFileTags
-        >> auxiliaryInputs
-        >> excludedAuxiliaryInputs
-        >> inputsFromDependencies
-        >> explicitlyDependsOn
-        >> multiplex
-        >> alwaysRun;
-
+    inputs.load(pool);
+    outputFileTags.load(pool);
+    auxiliaryInputs.load(pool);
+    excludedAuxiliaryInputs.load(pool);
+    inputsFromDependencies.load(pool);
+    explicitlyDependsOn.load(pool);
+    pool.stream() >> multiplex >> alwaysRun;
     pool.loadContainerS(artifacts);
 }
 
@@ -432,16 +425,13 @@ void Rule::store(PersistentPool &pool) const
     pool.store(prepareScript);
     pool.store(outputArtifactsScript);
     pool.store(module);
-    pool.stream()
-        << inputs
-        << outputFileTags
-        << auxiliaryInputs
-        << excludedAuxiliaryInputs
-        << inputsFromDependencies
-        << explicitlyDependsOn
-        << multiplex
-        << alwaysRun;
-
+    inputs.store(pool);
+    outputFileTags.store(pool);
+    auxiliaryInputs.store(pool);
+    excludedAuxiliaryInputs.store(pool);
+    inputsFromDependencies.store(pool);
+    explicitlyDependsOn.store(pool);
+    pool.stream() << multiplex << alwaysRun;
     pool.storeContainer(artifacts);
 }
 
@@ -504,9 +494,8 @@ FileTags ResolvedProduct::fileTagsForFileName(const QString &fileName) const
 
 void ResolvedProduct::load(PersistentPool &pool)
 {
-    pool.stream()
-        >> enabled
-        >> fileTags;
+    pool.stream() >> enabled;
+    fileTags.load(pool);
     name = pool.idLoadString();
     profile = pool.idLoadString();
     targetName = pool.idLoadString();
@@ -528,9 +517,8 @@ void ResolvedProduct::load(PersistentPool &pool)
 
 void ResolvedProduct::store(PersistentPool &pool) const
 {
-    pool.stream()
-        << enabled
-        << fileTags;
+    pool.stream() << enabled;
+    fileTags.store(pool);
     pool.storeString(name);
     pool.storeString(profile);
     pool.storeString(targetName);
@@ -1283,7 +1271,8 @@ bool artifactPropertyListsAreEqual(const QList<ArtifactPropertiesPtr> &l1,
 void ResolvedScanner::load(PersistentPool &pool)
 {
     module = pool.idLoadS<ResolvedModule>();
-    pool.stream() >> inputs >> recursive;
+    inputs.load(pool);
+    pool.stream() >> recursive;
     searchPathsScript = pool.idLoadS<ScriptFunction>();
     scanScript = pool.idLoadS<ScriptFunction>();
 }
@@ -1291,7 +1280,8 @@ void ResolvedScanner::load(PersistentPool &pool)
 void ResolvedScanner::store(PersistentPool &pool) const
 {
     pool.store(module);
-    pool.stream() << inputs << recursive;
+    inputs.store(pool);
+    pool.stream() << recursive;
     pool.store(searchPathsScript);
     pool.store(scanScript);
 }
diff --git a/src/lib/corelib/tools/persistence.cpp b/src/lib/corelib/tools/persistence.cpp
index fb4dbf70e..82890b688 100644
--- a/src/lib/corelib/tools/persistence.cpp
+++ b/src/lib/corelib/tools/persistence.cpp
@@ -50,7 +50,7 @@
 namespace qbs {
 namespace Internal {
 
-static const char QBS_PERSISTENCE_MAGIC[] = "QBSPERSISTENCE-91";
+static const char QBS_PERSISTENCE_MAGIC[] = "QBSPERSISTENCE-92";
 
 PersistentPool::PersistentPool(Logger &logger) : m_logger(logger)
 {