s_copysign.c 959 B

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  1. /* @(#)s_copysign.c 5.1 93/09/24 */
  2. /*
  3. * ====================================================
  4. * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
  5. *
  6. * Developed at SunPro, a Sun Microsystems, Inc. business.
  7. * Permission to use, copy, modify, and distribute this
  8. * software is freely granted, provided that this notice
  9. * is preserved.
  10. * ====================================================
  11. */
  12. #if defined(LIBM_SCCS) && !defined(lint)
  13. static char rcsid[] = "$NetBSD: s_copysign.c,v 1.8 1995/05/10 20:46:57 jtc Exp $";
  14. #endif
  15. /*
  16. * copysign(double x, double y)
  17. * copysign(x,y) returns a value with the magnitude of x and
  18. * with the sign bit of y.
  19. */
  20. #include "math.h"
  21. #include "math_private.h"
  22. #ifdef __STDC__
  23. double copysign(double x, double y)
  24. #else
  25. double copysign(x,y)
  26. double x,y;
  27. #endif
  28. {
  29. u_int32_t hx,hy;
  30. GET_HIGH_WORD(hx,x);
  31. GET_HIGH_WORD(hy,y);
  32. SET_HIGH_WORD(x,(hx&0x7fffffff)|(hy&0x80000000));
  33. return x;
  34. }