diff options
Diffstat (limited to 'lib/msun/src/k_cosf.c')
| -rw-r--r-- | lib/msun/src/k_cosf.c | 15 |
1 files changed, 7 insertions, 8 deletions
diff --git a/lib/msun/src/k_cosf.c b/lib/msun/src/k_cosf.c index 5ce7608..5835b80 100644 --- a/lib/msun/src/k_cosf.c +++ b/lib/msun/src/k_cosf.c @@ -1,5 +1,6 @@ /* k_cosf.c -- float version of k_cos.c * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. + * Debugged and optimized by Bruce D. Evans. */ /* @@ -20,14 +21,12 @@ static char rcsid[] = "$FreeBSD$"; #include "math.h" #include "math_private.h" +/* Range of maximum relative error in polynomial: ~[-1.15e-10, 1.169e-10]. */ static const float -one = 1.0000000000e+00, /* 0x3f800000 */ -C1 = 4.1666667908e-02, /* 0x3d2aaaab */ -C2 = -1.3888889225e-03, /* 0xbab60b61 */ -C3 = 2.4801587642e-05, /* 0x37d00d01 */ -C4 = -2.7557314297e-07, /* 0xb493f27c */ -C5 = 2.0875723372e-09, /* 0x310f74f6 */ -C6 = -1.1359647598e-11; /* 0xad47d74e */ +one = 1.0, +C1 = 0xaaaaa5.0p-28, /* 0.04166664555668830871582031250 */ +C2 = -0xb60615.0p-33, /* -0.001388731063343584537506103516 */ +C3 = 0xccf47d.0p-39; /* 0.00002443254288664320483803749084 */ float __kernel_cosf(float x, float y) @@ -35,7 +34,7 @@ __kernel_cosf(float x, float y) float hz,z,r,w; z = x*x; - r = z*(C1+z*(C2+z*(C3+z*(C4+z*(C5+z*C6))))); + r = z*(C1+z*(C2+z*C3)); hz = (float)0.5*z; w = one-hz; return w + (((one-w)-hz) + (z*r-x*y)); |
