Files
musl/src/math/scalbnf.c
Szabolcs Nagy 2eaed464e2 math: use float_t and double_t in scalbnf and scalbn
remove STRICT_ASSIGN (c99 semantics is assumed) and use the conventional
union to prepare the scaling factor (so libm.h is no longer needed)
2013-09-05 11:30:08 +00:00

32 lines
447 B
C

#include <math.h>
#include <stdint.h>
float scalbnf(float x, int n)
{
union {float f; uint32_t i;} u;
float_t y = x;
if (n > 127) {
y *= 0x1p127f;
n -= 127;
if (n > 127) {
y *= 0x1p127f;
n -= 127;
if (n > 127)
n = 127;
}
} else if (n < -126) {
y *= 0x1p-126f;
n += 126;
if (n < -126) {
y *= 0x1p-126f;
n += 126;
if (n < -126)
n = -126;
}
}
u.i = (uint32_t)(0x7f+n)<<23;
x = y * u.f;
return x;
}