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| | #include "libm.h"
double scalbn(double x, int n)
{
double scale;
if (n > 1023) {
x *= 0x1p1023;
n -= 1023;
if (n > 1023) {
x *= 0x1p1023;
n -= 1023;
if (n > 1023) {
STRICT_ASSIGN(double, x, x * 0x1p1023);
return x;
}
}
} else if (n < -1022) {
x *= 0x1p-1022;
n += 1022;
if (n < -1022) {
x *= 0x1p-1022;
n += 1022;
if (n < -1022) {
STRICT_ASSIGN(double, x, x * 0x1p-1022);
return x;
}
}
}
INSERT_WORDS(scale, (uint32_t)(0x3ff+n)<<20, 0);
STRICT_ASSIGN(double, x, x * scale);
return x;
}
|