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#define LOWP 16
#define FIXP 20
#define LOWMASK ((1<<LOWP)-1)
#define D (1<<(FIXP-LOWP))
#define H (1<<(2*LOWP-FIXP))
#define TPT(x, y) ((x)<<(y)) /* x * 2^y */
#define DPT(x, y) ((x)>>(y)) /* x / 2^y */
scalesp(s, d)
int s, d;
{
int sign;
unsigned int s1, s0, d1, d0;
sign = 1;
if (s < 0) {
sign = -1;
s *= -1;
}
s0 = s & LOWMASK;
d0 = d & LOWMASK;
s1 = s >> LOWP;
d1 = d >> LOWP;
return (sign *
(TPT(s1*d1, 2*LOWP-FIXP) +
DPT(s1*d0+s0*d1 + DPT(s0*d0, LOWP), FIXP-LOWP))
);
}
/* very stupid routine that computes x/y */
divsp(x, y)
int x, y;
{
int x0, x1, z0;
z0 = (int)(((float)x/(float)y)*(1<<FIXP)) - 5;
x0 = scalesp(y, z0);
x1 = scalesp(y, z0+1);
for (; x1 < x;) {
z0++;
x0 = x1;
x1 = scalesp(y, z0+1);
}
return z0+1;
}
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