comment

Author: TilmanNeumann

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

@@ -49,6 +49,8 @@ public void factor(BigInteger Nbig, SortedMultiset<BigInteger> primeFactors) {
 				} while (N%p == 0);
 				primeFactors.add(BigInteger.valueOf(p), exp);
 			}
+			// for random composite N, it is much much faster to check the termination condition after each p;
+			// for semiprime N, it would be ~40% faster to do it only after sucessful divisions
 			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

@@ -89,6 +89,8 @@ public void factor(BigInteger Nbig, int Nexp, SortedMultiset<BigInteger> primeFa
 				primeFactors.add(BigInteger.valueOf(p), Nexp);
 				N = q;
 			}
+			// for random composite N, it is much much faster to check the termination condition after each p;
+			// for semiprime N, it would be ~40% faster to do it only after sucessful divisions
 			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

@@ -80,6 +80,8 @@ 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
 			}
+			// for random composite N, it is much much faster to check the termination condition after each p;
+			// for semiprime N, it would be ~40% faster to do it only after sucessful divisions
 			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

@@ -64,6 +64,8 @@ public void factor(BigInteger Nbig, SortedMultiset<BigInteger> primeFactors) {
 				} while (N%p == 0);
 				primeFactors.add(BigInteger.valueOf(p), exp);
 			}
+			// for random composite N, it is much much faster to check the termination condition after each p;
+			// for semiprime N, it would be ~40% faster to do it only after sucessful divisions
 			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/TDiv63Inverse.java

@@ -128,6 +128,8 @@ public void factor(BigInteger Nbig, SortedMultiset<BigInteger> primeFactors) {
 			if (exp>0) {
 				primeFactors.add(BigInteger.valueOf(p), exp);
 			}
+			// for random composite N, it is much much faster to check the termination condition after each p;
+			// for semiprime N, it would be ~40% faster to do it only after sucessful divisions
 			if (((long)p) * p > N) { // move p as long into registers makes a performance difference
 				break; // the remaining N is prime
 			}