src: Improved performance of FilePathFilter (#1030)

* Only retrieve FilePath::wstr once per checked FilePath
* Replaced all invokation of FilePathFilter::isMatching with FilePathFilter::areMatching
* Don't pass match to std::regex_match
* set 'optimize' flag on regexes

partly fixes #1007

src/lib/project/SourceGroup.cpp

@@ -96,14 +96,7 @@ std::set<FilePath> SourceGroup::filterToContainedFilePaths(
 
 		if (isInIndexedPaths)
 		{
-			for (const FilePathFilter& excludeFilter: excludeFilters)
-			{
-				if (excludeFilter.isMatching(filePath))
-				{
-					isInIndexedPaths = false;
-					break;
-				}
-			}
+			isInIndexedPaths = !FilePathFilter::areMatching(excludeFilters, filePath);
 		}
 
 		if (isInIndexedPaths)

src/lib/utility/file/FileManager.cpp

@@ -56,13 +56,5 @@ std::set<FilePath> FileManager::getAllSourceFilePaths() const
 
 bool FileManager::isExcluded(const FilePath& filePath) const
 {
-	for (const FilePathFilter& filter: m_excludeFilters)
-	{
-		if (filter.isMatching(filePath))
-		{
-			return true;
-		}
-	}
-
-	return false;
+	return FilePathFilter::areMatching(m_excludeFilters, filePath);
 }

src/lib/utility/file/FilePathFilter.cpp

@@ -12,9 +12,12 @@ std::wstring FilePathFilter::wstr() const
 
 bool FilePathFilter::isMatching(const FilePath& filePath) const
 {
-	const std::wstring s = filePath.wstr();
-	std::wsmatch match;
-	return std::regex_match(s, match, m_filterRegex);
+	return isMatching(filePath.wstr());
+}
+
+bool FilePathFilter::isMatching(const std::wstring& fileStr) const
+{
+	return std::regex_match(fileStr, m_filterRegex);
 }
 
 bool FilePathFilter::operator<(const FilePathFilter& other) const
@@ -96,5 +99,5 @@ std::wregex FilePathFilter::convertFilterStringToRegex(const std::wstring& filte
 		regexFilterString = std::regex_replace(regexFilterString, regex, L"[^\\\\/]*");
 	}
 
-	return std::wregex(regexFilterString);
+	return std::wregex(regexFilterString, std::regex::optimize);
 }

src/lib/utility/file/FilePathFilter.h

@@ -9,11 +9,15 @@
 class FilePathFilter
 {
 public:
+	template<typename ContainerType>
+	static bool areMatching(const ContainerType& filters, const FilePath& filePath);
+
 	explicit FilePathFilter(const std::wstring& filterString);
 
 	std::wstring wstr() const;
 
 	bool isMatching(const FilePath& filePath) const;
+	bool isMatching(const std::wstring& fileStr) const;
 
 	bool operator<(const FilePathFilter& other) const;
 
@@ -24,4 +28,20 @@ private:
 	std::wregex m_filterRegex;
 };
 
+template<typename ContainerType>
+bool FilePathFilter::areMatching(const ContainerType& filters, const FilePath& filePath)
+{
+	const std::wstring fileStr = filePath.wstr();
+
+	for (const FilePathFilter& filter: filters)
+	{
+		if (filter.isMatching(fileStr))
+		{
+			return true;
+		}
+	}
+
+	return false;
+}
+
 #endif	  // FILE_PATH_FILTER_H

src/lib/utility/file/FileRegister.cpp

@@ -44,14 +44,7 @@ FileRegister::FileRegister(
 
 		if (ret)
 		{
-			for (const FilePathFilter& excludeFilter: m_excludeFilters)
-			{
-				if (excludeFilter.isMatching(filePath))
-				{
-					ret = false;
-					break;
-				}
-			}
+			ret = !FilePathFilter::areMatching(m_excludeFilters, filePath);
 		}
 		return ret;
 	})

src/lib_cxx/project/SourceGroupCxxCdb.cpp

@@ -64,16 +64,7 @@ std::set<FilePath> SourceGroupCxxCdb::getAllSourceFilePaths(
 		for (const FilePath& path: IndexerCommandCxx::getSourceFilesFromCDB(
 				 cdb, m_settings->getCompilationDatabasePathExpandedAndAbsolute()))
 		{
-			bool excluded = false;
-			for (const FilePathFilter& filter: excludeFilters)
-			{
-				if (filter.isMatching(path))
-				{
-					excluded = true;
-					break;
-				}
-			}
-
+			bool excluded = FilePathFilter::areMatching(excludeFilters, path);
 			if (!excluded && path.exists())
 			{
 				sourceFilePaths.insert(path);

src/lib_cxx/project/SourceGroupCxxCodeblocks.cpp

@@ -52,16 +52,7 @@ std::set<FilePath> SourceGroupCxxCodeblocks::getAllSourceFilePaths() const
 		for (const FilePath& filePath:
 			 project->getAllSourceFilePathsCanonical(m_settings->getSourceExtensions()))
 		{
-			bool isExcluded = false;
-			for (const FilePathFilter& excludeFilter: excludeFilters)
-			{
-				if (excludeFilter.isMatching(filePath))
-				{
-					isExcluded = true;
-					break;
-				}
-			}
-
+			bool isExcluded = FilePathFilter::areMatching(excludeFilters, filePath);
 			if (!isExcluded && filePath.exists())
 			{
 				sourceFilePaths.insert(filePath);