avoid readRepresentativesLookupVectorFromFiles_par() container realloc

Author: xamidi

nortmann/DlProofEnumerator.cpp

@@ -97,7 +97,7 @@ bool DlProofEnumerator::readRepresentativesLookupVectorFromFiles_seq(vector<vect
 	return true;
 }
 
-bool DlProofEnumerator::readRepresentativesLookupVectorFromFiles_par(vector<vector<string>>& allRepresentativesLookup, vector<vector<string>>* optOut_allConclusionsLookup, bool debug, unsigned concurrencyCount, const string& filePrefix, const string& filePostfix, bool initFresh) {
+bool DlProofEnumerator::readRepresentativesLookupVectorFromFiles_par(vector<vector<string>>& allRepresentativesLookup, vector<vector<string>>* optOut_allConclusionsLookup, bool debug, unsigned concurrencyCount, const string& filePrefix, const string& filePostfix, bool initFresh, size_t containerReserve) {
 	if (concurrencyCount < 2)
 		return readRepresentativesLookupVectorFromFiles_seq(allRepresentativesLookup, optOut_allConclusionsLookup, debug, filePrefix, filePostfix, initFresh); // system cannot execute threads concurrently
 	chrono::time_point<chrono::steady_clock> startTime;
@@ -116,6 +116,9 @@ bool DlProofEnumerator::readRepresentativesLookupVectorFromFiles_par(vector<vect
 	vector<thread> threads;
 	unsigned t = 0;
 	bool abortAll = false;
+	allRepresentativesLookup.reserve(containerReserve); // ensure that no container reallocations happen during concurrent access, since they would result in data races
+	if (optOut_allConclusionsLookup)
+		optOut_allConclusionsLookup->reserve(containerReserve);
 	for (uint32_t wordLengthLimit = allRepresentativesLookup.size() + 1; true; wordLengthLimit += 2) { // look for files containing D-proofs, starting from built-in limit + 2
 		const string file = filePrefix + to_string(wordLengthLimit) + filePostfix;
 		if (filesystem::exists(file)) { // load

nortmann/DlProofEnumerator.h

@@ -30,7 +30,7 @@ struct DlProofEnumerator {
 	static const std::vector<const std::vector<std::string>*>& builtinConclusions();
 	static std::vector<std::vector<std::string>> composeToLookupVector(const std::vector<const std::vector<std::string>*>& all);
 	static bool readRepresentativesLookupVectorFromFiles_seq(std::vector<std::vector<std::string>>& allRepresentativesLookup, std::vector<std::vector<std::string>>* optOut_allConclusionsLookup, bool debug = false, const std::string& filePrefix = "data/dProofs", const std::string& filePostfix = ".txt", bool initFresh = true);
-	static bool readRepresentativesLookupVectorFromFiles_par(std::vector<std::vector<std::string>>& allRepresentativesLookup, std::vector<std::vector<std::string>>* optOut_allConclusionsLookup, bool debug = false, unsigned concurrencyCount = std::thread::hardware_concurrency(), const std::string& filePrefix = "data/dProofs", const std::string& filePostfix = ".txt", bool initFresh = true);
+	static bool readRepresentativesLookupVectorFromFiles_par(std::vector<std::vector<std::string>>& allRepresentativesLookup, std::vector<std::vector<std::string>>* optOut_allConclusionsLookup, bool debug = false, unsigned concurrencyCount = std::thread::hardware_concurrency(), const std::string& filePrefix = "data/dProofs", const std::string& filePostfix = ".txt", bool initFresh = true, std::size_t containerReserve = 100);
 	static std::vector<std::pair<std::array<std::uint32_t, 2>, unsigned>> proofLengthCombinations(std::uint32_t knownLimit);
 
 	// Data generation