k_sinf.c 1.3 KB

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  1. /* k_sinf.c -- float version of k_sin.c
  2. * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
  3. * Optimized by Bruce D. Evans.
  4. */
  5. /*
  6. * ====================================================
  7. * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
  8. *
  9. * Developed at SunPro, a Sun Microsystems, Inc. business.
  10. * Permission to use, copy, modify, and distribute this
  11. * software is freely granted, provided that this notice
  12. * is preserved.
  13. * ====================================================
  14. */
  15. #ifndef INLINE_KERNEL_SINDF
  16. #include "cdefs-compat.h"
  17. //__FBSDID("$FreeBSD: src/lib/msun/src/k_sinf.c,v 1.16 2009/06/03 08:16:34 ed Exp $");
  18. #endif
  19. #include <openlibm_math.h>
  20. #include "math_private.h"
  21. /* |sin(x)/x - s(x)| < 2**-37.5 (~[-4.89e-12, 4.824e-12]). */
  22. static const double
  23. S1 = -0x15555554cbac77.0p-55, /* -0.166666666416265235595 */
  24. S2 = 0x111110896efbb2.0p-59, /* 0.0083333293858894631756 */
  25. S3 = -0x1a00f9e2cae774.0p-65, /* -0.000198393348360966317347 */
  26. S4 = 0x16cd878c3b46a7.0p-71; /* 0.0000027183114939898219064 */
  27. #ifndef INLINE_KERNEL_SINDF
  28. extern
  29. #endif
  30. //__inline float
  31. OLM_DLLEXPORT float
  32. __kernel_sindf(double x)
  33. {
  34. double r, s, w, z;
  35. /* Try to optimize for parallel evaluation as in k_tanf.c. */
  36. z = x*x;
  37. w = z*z;
  38. r = S3+z*S4;
  39. s = z*x;
  40. return (x + s*(S1+z*S2)) + s*w*r;
  41. }