diff options
Diffstat (limited to 'src/math/sinf.c')
| -rw-r--r-- | src/math/sinf.c | 33 |
1 files changed, 18 insertions, 15 deletions
diff --git a/src/math/sinf.c b/src/math/sinf.c index dcca67af..64e39f50 100644 --- a/src/math/sinf.c +++ b/src/math/sinf.c @@ -26,35 +26,38 @@ s4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */ float sinf(float x) { double y; - int32_t n, hx, ix; + uint32_t ix; + int n, sign; - GET_FLOAT_WORD(hx, x); - ix = hx & 0x7fffffff; + GET_FLOAT_WORD(ix, x); + sign = ix >> 31; + ix &= 0x7fffffff; if (ix <= 0x3f490fda) { /* |x| ~<= pi/4 */ - if (ix < 0x39800000) /* |x| < 2**-12 */ - /* raise inexact if x != 0 */ - if((int)x == 0) - return x; + if (ix < 0x39800000) { /* |x| < 2**-12 */ + /* raise inexact if x!=0 and underflow if subnormal */ + FORCE_EVAL(ix < 0x00800000 ? x/0x1p120f : x+0x1p120f); + return x; + } return __sindf(x); } if (ix <= 0x407b53d1) { /* |x| ~<= 5*pi/4 */ if (ix <= 0x4016cbe3) { /* |x| ~<= 3pi/4 */ - if (hx > 0) - return __cosdf(x - s1pio2); - else + if (sign) return -__cosdf(x + s1pio2); + else + return __cosdf(x - s1pio2); } - return __sindf(hx > 0 ? s2pio2 - x : -s2pio2 - x); + return __sindf(sign ? -(x + s2pio2) : -(x - s2pio2)); } if (ix <= 0x40e231d5) { /* |x| ~<= 9*pi/4 */ if (ix <= 0x40afeddf) { /* |x| ~<= 7*pi/4 */ - if (hx > 0) - return -__cosdf(x - s3pio2); - else + if (sign) return __cosdf(x + s3pio2); + else + return -__cosdf(x - s3pio2); } - return __sindf(hx > 0 ? x - s4pio2 : x + s4pio2); + return __sindf(sign ? x + s4pio2 : x - s4pio2); } /* sin(Inf or NaN) is NaN */ |