qmake: use reserve to optimize memory allocation.

Change-Id: I6ace338512c24fd9dc11c767a28f0a63454076fa
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>

qmake/generators/mac/pbuilder_pbx.cpp

@@ -1004,7 +1004,10 @@ ProjectBuilderMakefileGenerator::writeMakeParts(QTextStream &t)
         ProStringList outputPaths;
         const ProStringList &archs = project->values("QMAKE_XCODE_ARCHS");
         if (!archs.isEmpty()) {
-            for (int i = 0; i < archs.size(); ++i) {
+            const int size = archs.size();
+            inputPaths.reserve(size);
+            outputPaths.reserve(size);
+            for (int i = 0; i < size; ++i) {
                 const ProString &arch = archs.at(i);
                 inputPaths << "$(OBJECT_FILE_DIR_$(CURRENT_VARIANT))/" + arch + "/";
                 outputPaths << "$(LINK_FILE_LIST_$(CURRENT_VARIANT)_" + arch + ")";

qmake/generators/makefile.cpp

@@ -776,6 +776,7 @@ MakefileGenerator::init()
         if(project->isActiveConfig("depend_includepath"))
             incDirs += v["INCLUDEPATH"];
         QList<QMakeLocalFileName> deplist;
+        deplist.reserve(incDirs.size());
         for (ProStringList::Iterator it = incDirs.begin(); it != incDirs.end(); ++it)
             deplist.append(QMakeLocalFileName((*it).toQString()));
         QMakeSourceFileInfo::setDependencyPaths(deplist);
@@ -1010,6 +1011,7 @@ MakefileGenerator::writeProjectMakefile()
     QList<SubTarget*> targets;
     {
         ProStringList builds = project->values("BUILDS");
+        targets.reserve(builds.size());
         for (ProStringList::Iterator it = builds.begin(); it != builds.end(); ++it) {
             SubTarget *st = new SubTarget;
             targets.append(st);
@@ -1450,7 +1452,9 @@ QString
 MakefileGenerator::fixFileVarGlue(const ProKey &var, const QString &before, const QString &glue, const QString &after) const
 {
     ProStringList varList;
-    for (const ProString &val : project->values(var))
+    const auto values = project->values(var);
+    varList.reserve(values.size());
+    for (const ProString &val : values)
         varList << escapeFilePath(Option::fixPathToTargetOS(val.toQString()));
     return valGlue(varList, before, glue, after);
 }
@@ -2803,7 +2807,9 @@ ProStringList
 MakefileGenerator::escapeFilePaths(const ProStringList &paths) const
 {
     ProStringList ret;
-    for (int i = 0; i < paths.size(); ++i)
+    const int size = paths.size();
+    ret.reserve(size);
+    for (int i = 0; i < size; ++i)
         ret.append(escapeFilePath(paths.at(i)));
     return ret;
 }
@@ -2818,7 +2824,9 @@ QStringList
 MakefileGenerator::escapeDependencyPaths(const QStringList &paths) const
 {
     QStringList ret;
-    for(int i = 0; i < paths.size(); ++i)
+    const int size = paths.size();
+    ret.reserve(size);
+    for (int i = 0; i < size; ++i)
         ret.append(escapeDependencyPath(paths.at(i)));
     return ret;
 }
@@ -2827,7 +2835,9 @@ ProStringList
 MakefileGenerator::escapeDependencyPaths(const ProStringList &paths) const
 {
     ProStringList ret;
-    for (int i = 0; i < paths.size(); ++i)
+    const int size = paths.size();
+    ret.reserve(size);
+    for (int i = 0; i < size; ++i)
         ret.append(escapeDependencyPath(paths.at(i).toQString()));
     return ret;
 }

qmake/generators/win32/msvc_nmake.cpp

@@ -44,6 +44,7 @@ QT_BEGIN_NAMESPACE
 static QString nmakePathList(const QStringList &list)
 {
     QStringList pathList;
+    pathList.reserve(list.size());
     for (const QString &path : list)
         pathList.append(QDir::cleanPath(path));
 
@@ -91,6 +92,7 @@ NmakeMakefileGenerator::writeMakefile(QTextStream &t)
                     t << "\nPATH = " << sdk.binPath() << "\n";
                 } else {
                     QStringList sdkStringList;
+                    sdkStringList.reserve(sdkList.size());
                     for (const CeSdkInfo &info : sdkList)
                         sdkStringList << info.name();
 

qmake/generators/win32/winmakefile.cpp

@@ -263,7 +263,9 @@ void Win32MakefileGenerator::processRcFileVar()
         QString versionString = vers.join('.');
 
         QStringList rcIcons;
-        for (const ProString &icon : project->values("RC_ICONS"))
+        const auto icons = project->values("RC_ICONS");
+        rcIcons.reserve(icons.size());
+        for (const ProString &icon : icons)
             rcIcons.append(fileFixify(icon.toQString(), FileFixifyAbsolute));
 
         QString companyName;

qmake/generators/xmloutput.cpp

@@ -81,6 +81,7 @@ XmlOutput::XMLState XmlOutput::state()
 void XmlOutput::updateIndent()
 {
     currentIndent.clear();
+    currentIndent.reserve(currentLevel);
     for (int i = 0; i < currentLevel; ++i)
         currentIndent.append(indent);
 }

qmake/library/qmakebuiltins.cpp

@@ -145,6 +145,7 @@ void QMakeEvaluator::initFunctionStatics()
         { "shell_quote", E_SHELL_QUOTE },
         { "getenv", E_GETENV },
     };
+    statics.expands.reserve((int)(sizeof(expandInits)/sizeof(expandInits[0])));
     for (unsigned i = 0; i < sizeof(expandInits)/sizeof(expandInits[0]); ++i)
         statics.expands.insert(ProKey(expandInits[i].name), expandInits[i].func);
 
@@ -186,6 +187,7 @@ void QMakeEvaluator::initFunctionStatics()
         { "touch", T_TOUCH },
         { "cache", T_CACHE },
     };
+    statics.functions.reserve((int)(sizeof(testInits)/sizeof(testInits[0])));
     for (unsigned i = 0; i < sizeof(testInits)/sizeof(testInits[0]); ++i)
         statics.functions.insert(ProKey(testInits[i].name), testInits[i].func);
 }

qmake/library/qmakeevaluator.cpp

@@ -186,6 +186,7 @@ void QMakeEvaluator::initStatics()
         { "IN_PWD", "PWD" },
         { "DEPLOYMENT", "INSTALLS" }
     };
+    statics.varMap.reserve((int)(sizeof(mapInits)/sizeof(mapInits[0])));
     for (unsigned i = 0; i < sizeof(mapInits)/sizeof(mapInits[0]); ++i)
         statics.varMap.insert(ProKey(mapInits[i].oldname), ProKey(mapInits[i].newname));
 }
@@ -755,12 +756,14 @@ QMakeEvaluator::VisitReturn QMakeEvaluator::visitProLoop(
                 if (ok) {
                     int end = itl.mid(dotdot+2).toInt(&ok);
                     if (ok) {
-                        if (m_cumulative && qAbs(end - start) > 100) {
+                        const int absDiff = qAbs(end - start);
+                        if (m_cumulative && absDiff > 100) {
                             // Such a loop is unlikely to contribute something useful to the
                             // file collection, and may cause considerable delay.
                             traceMsg("skipping excessive loop in cumulative mode");
                             return ReturnFalse;
                         }
+                        list.reserve(absDiff + 1);
                         if (start < end) {
                             for (int i = start; i <= end; i++)
                                 list << ProString(QString::number(i));

qmake/option.cpp

@@ -391,6 +391,7 @@ Option::init(int argc, char **argv)
     }
     if(argc && argv) {
         QStringList args;
+        args.reserve(argc - 1);
         for (int i = 1; i < argc; i++)
             args << QString::fromLocal8Bit(argv[i]);