71 lines
1.4 KiB
C
71 lines
1.4 KiB
C
/*****************************************************************************/
|
|
/*****************************************************************************/
|
|
// fmodf from musl-0.9.15
|
|
/*****************************************************************************/
|
|
/*****************************************************************************/
|
|
|
|
#include "libm.h"
|
|
|
|
float fmodf(float x, float y)
|
|
{
|
|
union {float f; uint32_t i;} ux = {x}, uy = {y};
|
|
int ex = ux.i>>23 & 0xff;
|
|
int ey = uy.i>>23 & 0xff;
|
|
uint32_t sx = ux.i & 0x80000000;
|
|
uint32_t i;
|
|
uint32_t uxi = ux.i;
|
|
|
|
if (uy.i<<1 == 0 || isnan(y) || ex == 0xff)
|
|
return (x*y)/(x*y);
|
|
if (uxi<<1 <= uy.i<<1) {
|
|
if (uxi<<1 == uy.i<<1)
|
|
return 0*x;
|
|
return x;
|
|
}
|
|
|
|
/* normalize x and y */
|
|
if (!ex) {
|
|
for (i = uxi<<9; i>>31 == 0; ex--, i <<= 1);
|
|
uxi <<= -ex + 1;
|
|
} else {
|
|
uxi &= -1U >> 9;
|
|
uxi |= 1U << 23;
|
|
}
|
|
if (!ey) {
|
|
for (i = uy.i<<9; i>>31 == 0; ey--, i <<= 1);
|
|
uy.i <<= -ey + 1;
|
|
} else {
|
|
uy.i &= -1U >> 9;
|
|
uy.i |= 1U << 23;
|
|
}
|
|
|
|
/* x mod y */
|
|
for (; ex > ey; ex--) {
|
|
i = uxi - uy.i;
|
|
if (i >> 31 == 0) {
|
|
if (i == 0)
|
|
return 0*x;
|
|
uxi = i;
|
|
}
|
|
uxi <<= 1;
|
|
}
|
|
i = uxi - uy.i;
|
|
if (i >> 31 == 0) {
|
|
if (i == 0)
|
|
return 0*x;
|
|
uxi = i;
|
|
}
|
|
for (; uxi>>23 == 0; uxi <<= 1, ex--);
|
|
|
|
/* scale result up */
|
|
if (ex > 0) {
|
|
uxi -= 1U << 23;
|
|
uxi |= (uint32_t)ex << 23;
|
|
} else {
|
|
uxi >>= -ex + 1;
|
|
}
|
|
uxi |= sx;
|
|
ux.i = uxi;
|
|
return ux.f;
|
|
}
|