performance improvement for N>=32 bit

Author: TilmanNeumann

src/main/java/de/tilman_neumann/jml/factor/tdiv/TDiv.java

@@ -113,9 +113,9 @@ public void searchFactors(FactorArguments args, FactorResult result) {
 				addToMap(p_i_big, exp*Nexp, primeFactors);
 				if (N.bitLength() < 63) {
 					// Check if we are done
-					long p_i_square = p_i *(long)p_i;
+					long p_i_square = ((long)p_i) * p_i;
 					if (p_i_square > N.longValue()) {
-						if (DEBUG) LOG.debug("N=" + N + " < p^2=" + p_i_square);
+						if (DEBUG) LOG.debug("N=" + N + " < p^2 = " + p_i_square);
 						// the remaining N is 1 or prime
 						if (N.compareTo(I_1)>0) addToMap(N, Nexp, primeFactors);
 						result.smallestPossibleFactor = p_i; // may be helpful in following factor algorithms

src/main/java/de/tilman_neumann/jml/factor/tdiv/TDiv31.java

@@ -49,7 +49,7 @@ public void factor(BigInteger Nbig, SortedMultiset<BigInteger> primeFactors) {
 				} while (N%p == 0);
 				primeFactors.add(BigInteger.valueOf(p), exp);
 			}
-			if (p*(long)p > N) {
+			if (((long)p) * p > N) { // move p as long into registers makes a performance difference
 				if (N>1) primeFactors.add(BigInteger.valueOf(N));
 				break;
 			}

src/main/java/de/tilman_neumann/jml/factor/tdiv/TDiv31Barrett.java

@@ -89,7 +89,7 @@ public void factor(BigInteger Nbig, int Nexp, SortedMultiset<BigInteger> primeFa
 				primeFactors.add(BigInteger.valueOf(p), Nexp);
 				N = q;
 			}
-			if (p*(long)p > N) {
+			if (((long)p) * p > N) { // move p as long into registers makes a performance difference
 				break;
 			}
 		}

src/main/java/de/tilman_neumann/jml/factor/tdiv/TDiv31Inverse.java

@@ -80,7 +80,7 @@ public void factor(BigInteger Nbig, int Nexp, SortedMultiset<BigInteger> primeFa
 				primeFactors.add(BigInteger.valueOf(p), Nexp);
 				N = q; // avoiding a division here by storing q benefits the int version but not the long version
 			}
-			if (p*(long)p > N) {
+			if (((long)p) * p > N) { // move p as long into registers makes a performance difference
 				break;
 			}
 		}

src/main/java/de/tilman_neumann/jml/factor/tdiv/TDiv63.java

@@ -64,7 +64,7 @@ public void factor(BigInteger Nbig, SortedMultiset<BigInteger> primeFactors) {
 				} while (N%p == 0);
 				primeFactors.add(BigInteger.valueOf(p), exp);
 			}
-			if (p*(long)p > N) {
+			if (((long)p) * p > N) { // move p as long into registers makes a performance difference
 				break;
 			}
 		}
@@ -110,7 +110,7 @@ public void searchFactors(FactorArguments args, FactorResult result) {
 				// At least one division has occurred, add the factor(s) to the result map
 				addToMap(BigInteger.valueOf(p_i), exp*Nexp, primeFactors);
 				// Check if we are done
-				if (p_i *(long)p_i > N) {
+				if (((long)p_i) * p_i > N) { // move p as long into registers makes a performance difference
 					// the remaining N is 1 or prime
 					if (N>1) addToMap(BigInteger.valueOf(N), Nexp, primeFactors);
 					result.smallestPossibleFactor = p_i; // may be helpful in following factor algorithms

src/main/java/de/tilman_neumann/jml/factor/tdiv/TDiv63Inverse.java

@@ -128,7 +128,7 @@ public void factor(BigInteger Nbig, SortedMultiset<BigInteger> primeFactors) {
 			if (exp>0) {
 				primeFactors.add(BigInteger.valueOf(p), exp);
 			}
-			if (p*(long)p > N) {
+			if (((long)p) * p > N) { // move p as long into registers makes a performance difference
 				break; // the remaining N is prime
 			}
 		}
@@ -176,7 +176,7 @@ public void searchFactors(FactorArguments args, FactorResult result) {
 				// At least one division has occurred, add the factor(s) to the result map
 				addToMap(BigInteger.valueOf(p_i), exp*Nexp, primeFactors);
 				// Check if we are done
-				if (p_i *(long)p_i > N) {
+				if (((long)p_i) * p_i > N) { // move p as long into registers makes a performance difference
 					// the remaining N is 1 or prime
 					if (N>1) addToMap(BigInteger.valueOf(N), Nexp, primeFactors);
 					result.smallestPossibleFactor = p_i; // may be helpful in following factor algorithms