Optimized NTT

src/core/lib/math/transfrm.cpp

@@ -224,24 +224,25 @@ void NumberTheoreticTransform<VecType>::ForwardTransformToBitReverse(const VecTy
 
 	result->SetModulus(modulus);
 
-	usint i, m, j1, j2, indexOmega, indexLo, indexHi;
-	NativeInteger preconOmega;
-	IntType omega, omegaFactor, loVal, hiVal, zero(0);
-
-	for (i = 0; i < n; ++i) {
+	for (uint32_t i = 0; i < n; ++i) {
 		(*result)[i]= element[i];
 	}
 
+	uint32_t indexOmega, indexHi;
+	NativeInteger preconOmega;
+	IntType omega, omegaFactor, loVal, hiVal, zero(0);
+
 	usint t = (n >> 1);
 	usint logt1 = GetMSB64(t);
-	for (m = 1; m < n; m <<= 1) {
-		for (i = 0; i < m; ++i) {
+	for (uint32_t m = 1; m < n; m <<= 1, t >>= 1, --logt1) {
+		uint32_t j1, j2;
+		for (uint32_t i = 0; i < m; ++i) {
 			j1 = i << logt1;
 			j2 = j1 + t;
 			indexOmega = m + i;
 			omega = rootOfUnityTable[indexOmega];
 			preconOmega = preconRootOfUnityTable[indexOmega];
-			for (indexLo = j1; indexLo < j2; ++indexLo) {
+			for (uint32_t indexLo = j1; indexLo < j2; ++indexLo) {
 				indexHi = indexLo + t;
 				loVal = (*result)[indexLo];
 				omegaFactor = (*result)[indexHi];
@@ -265,8 +266,6 @@ void NumberTheoreticTransform<VecType>::ForwardTransformToBitReverse(const VecTy
 				}
 			}
 		}
-		t >>= 1;
-		logt1--;
 	}
 	return;
 }