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unsigned int modulo(unsigned int x, unsigned int y)
{
unsigned int r0, q0, y0, y1;
r0 = x;
q0 = 0;
y0 = y;
y1 = y;
do
{
y1 = 2 * y1;
}
while (y1 <= x);
do
{
y1 = y1 / 2;
q0 = 2 * q0;
if (r0 >= y1)
{
r0 = r0 - y1;
q0 = q0 + 1;
}
}
while ((int)y1 != (int)y0);
return r0;
}
int smodulo(int N, int D) {
if (D < 0) {
if (N < 0)
return modulo(-N, -D);
else
return -modulo(N, -D);
} else {
if (N < 0)
return -modulo(-N, D);
else
return modulo(N, D);
}
}
unsigned divider_fast(unsigned x, unsigned y) {
unsigned r0, q0, y0, y1;
r0 = x;
q0 = 0;
y0 = y;
y1 = y;
do {
y1 = 2 * y1;
} while (y1 <= x);
do {
y1 /= 2;
q0 *= 2;
if (r0 >= y1) {
r0 -= y1;
q0++;
}
} while ((int)y1 != (int)y0);
return q0;
}
unsigned divider(unsigned x, unsigned y) {
unsigned q0, acc;
q0 = 0;
acc = y;
while (acc <= x) {
q0++;
acc += y;
}
return q0;
}
/*
* Signed division operation for faster frequency division.
*/
int sdivider(int N, int D) {
if (D < 0) {
if (N < 0)
return divider(-N, -D);
else
return -divider(N, -D);
} else {
if (N < 0)
return -divider(-N, D);
else
return divider(N, D);
}
}
int sdivider_fast(int N, int D) {
if (D < 0) {
if (N < 0)
return divider_fast(-N, -D);
else
return -divider_fast(N, -D);
} else {
if (N < 0)
return -divider_fast(-N, D);
else
return divider_fast(N, D);
}
}
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