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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 2 | pj | 1 | /* e_sinhf.c -- float version of e_sinh.c. |
| 2 | * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. |
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| 3 | */ |
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| 4 | |||
| 5 | /* |
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| 6 | * ==================================================== |
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| 7 | * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
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| 8 | * |
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| 9 | * Developed at SunPro, a Sun Microsystems, Inc. business. |
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| 10 | * Permission to use, copy, modify, and distribute this |
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| 11 | * software is freely granted, provided that this notice |
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| 12 | * is preserved. |
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| 13 | * ==================================================== |
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| 14 | */ |
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| 15 | |||
| 16 | #ifndef lint |
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| 17 | static char rcsid[] = "$\Id: e_sinhf.c,v 1.2 1995/05/30 05:48:49 rgrimes Exp $"; |
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| 18 | #endif |
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| 19 | |||
| 20 | #include "math.h" |
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| 21 | #include "math_private.h" |
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| 22 | |||
| 23 | #ifdef __STDC__ |
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| 24 | static const float one = 1.0, shuge = 1.0e37; |
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| 25 | #else |
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| 26 | static float one = 1.0, shuge = 1.0e37; |
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| 27 | #endif |
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| 28 | |||
| 29 | #ifdef __STDC__ |
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| 30 | float __ieee754_sinhf(float x) |
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| 31 | #else |
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| 32 | float __ieee754_sinhf(x) |
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| 33 | float x; |
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| 34 | #endif |
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| 35 | { |
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| 36 | float t,w,h; |
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| 37 | int32_t ix,jx; |
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| 38 | |||
| 39 | GET_FLOAT_WORD(jx,x); |
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| 40 | ix = jx&0x7fffffff; |
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| 41 | |||
| 42 | /* x is INF or NaN */ |
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| 43 | if(ix>=0x7f800000) return x+x; |
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| 44 | |||
| 45 | h = 0.5; |
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| 46 | if (jx<0) h = -h; |
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| 47 | /* |x| in [0,22], return sign(x)*0.5*(E+E/(E+1))) */ |
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| 48 | if (ix < 0x41b00000) { /* |x|<22 */ |
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| 49 | if (ix<0x31800000) /* |x|<2**-28 */ |
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| 50 | if(shuge+x>one) return x;/* sinh(tiny) = tiny with inexact */ |
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| 51 | t = expm1f(fabsf(x)); |
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| 52 | if(ix<0x3f800000) return h*((float)2.0*t-t*t/(t+one)); |
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| 53 | return h*(t+t/(t+one)); |
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| 54 | } |
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| 55 | |||
| 56 | /* |x| in [22, log(maxdouble)] return 0.5*exp(|x|) */ |
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| 57 | if (ix < 0x42b17180) return h*__ieee754_expf(fabsf(x)); |
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| 58 | |||
| 59 | /* |x| in [log(maxdouble), overflowthresold] */ |
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| 60 | if (ix<=0x42b2d4fc) { |
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| 61 | w = __ieee754_expf((float)0.5*fabsf(x)); |
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| 62 | t = h*w; |
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| 63 | return t*w; |
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| 64 | } |
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| 65 | |||
| 66 | /* |x| > overflowthresold, sinh(x) overflow */ |
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| 67 | return x*shuge; |
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| 68 | } |