s_expm1f.c (59b19ff14a36bb975819fff8c7bd8648a9b29537) | s_expm1f.c (a00672cff92a23dd28a5e6a1f3a52189eb0d7d7a) |
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1/* s_expm1f.c -- float version of s_expm1.c. 2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 3 */ 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 | 1/* s_expm1f.c -- float version of s_expm1.c. 2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 3 */ 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 |
16#ifndef lint 17static char rcsid[] = "$FreeBSD$"; 18#endif | 16#include <sys/cdefs.h> 17__FBSDID("$FreeBSD$"); |
19 20#include "math.h" 21#include "math_private.h" 22 23static const float 24one = 1.0, 25huge = 1.0e+30, 26tiny = 1.0e-30, --- 6 unchanged lines hidden (view full) --- 33Q2 = 1.5873016091e-03, /* 0x3ad00d01 */ 34Q3 = -7.9365076090e-05, /* 0xb8a670cd */ 35Q4 = 4.0082177293e-06, /* 0x36867e54 */ 36Q5 = -2.0109921195e-07; /* 0xb457edbb */ 37 38float 39expm1f(float x) 40{ | 18 19#include "math.h" 20#include "math_private.h" 21 22static const float 23one = 1.0, 24huge = 1.0e+30, 25tiny = 1.0e-30, --- 6 unchanged lines hidden (view full) --- 32Q2 = 1.5873016091e-03, /* 0x3ad00d01 */ 33Q3 = -7.9365076090e-05, /* 0xb8a670cd */ 34Q4 = 4.0082177293e-06, /* 0x36867e54 */ 35Q5 = -2.0109921195e-07; /* 0xb457edbb */ 36 37float 38expm1f(float x) 39{ |
41 float y,hi,lo,c,t,e,hxs,hfx,r1; | 40 float y,hi,lo,c,t,e,hxs,hfx,r1,twopk; |
42 int32_t k,xsb; 43 u_int32_t hx; 44 45 GET_FLOAT_WORD(hx,x); 46 xsb = hx&0x80000000; /* sign bit of x */ 47 if(xsb==0) y=x; else y= -x; /* y = |x| */ 48 hx &= 0x7fffffff; /* high word of |x| */ 49 --- 37 unchanged lines hidden (view full) --- 87 /* x is now in primary range */ 88 hfx = (float)0.5*x; 89 hxs = x*hfx; 90 r1 = one+hxs*(Q1+hxs*(Q2+hxs*(Q3+hxs*(Q4+hxs*Q5)))); 91 t = (float)3.0-r1*hfx; 92 e = hxs*((r1-t)/((float)6.0 - x*t)); 93 if(k==0) return x - (x*e-hxs); /* c is 0 */ 94 else { | 41 int32_t k,xsb; 42 u_int32_t hx; 43 44 GET_FLOAT_WORD(hx,x); 45 xsb = hx&0x80000000; /* sign bit of x */ 46 if(xsb==0) y=x; else y= -x; /* y = |x| */ 47 hx &= 0x7fffffff; /* high word of |x| */ 48 --- 37 unchanged lines hidden (view full) --- 86 /* x is now in primary range */ 87 hfx = (float)0.5*x; 88 hxs = x*hfx; 89 r1 = one+hxs*(Q1+hxs*(Q2+hxs*(Q3+hxs*(Q4+hxs*Q5)))); 90 t = (float)3.0-r1*hfx; 91 e = hxs*((r1-t)/((float)6.0 - x*t)); 92 if(k==0) return x - (x*e-hxs); /* c is 0 */ 93 else { |
94 SET_FLOAT_WORD(twopk,0x3f800000+(k<<23)); /* 2^k */ |
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95 e = (x*(e-c)-c); 96 e -= hxs; 97 if(k== -1) return (float)0.5*(x-e)-(float)0.5; 98 if(k==1) 99 if(x < (float)-0.25) return -(float)2.0*(e-(x+(float)0.5)); 100 else return one+(float)2.0*(x-e); 101 if (k <= -2 || k>56) { /* suffice to return exp(x)-1 */ | 95 e = (x*(e-c)-c); 96 e -= hxs; 97 if(k== -1) return (float)0.5*(x-e)-(float)0.5; 98 if(k==1) 99 if(x < (float)-0.25) return -(float)2.0*(e-(x+(float)0.5)); 100 else return one+(float)2.0*(x-e); 101 if (k <= -2 || k>56) { /* suffice to return exp(x)-1 */ |
102 int32_t i; | |
103 y = one-(e-x); | 102 y = one-(e-x); |
104 GET_FLOAT_WORD(i,y); 105 SET_FLOAT_WORD(y,i+(k<<23)); /* add k to y's exponent */ | 103 if (k == 128) y = y*2.0F*0x1p127F; 104 else y = y*twopk; |
106 return y-one; 107 } 108 t = one; 109 if(k<23) { | 105 return y-one; 106 } 107 t = one; 108 if(k<23) { |
110 int32_t i; | |
111 SET_FLOAT_WORD(t,0x3f800000 - (0x1000000>>k)); /* t=1-2^-k */ 112 y = t-(e-x); | 109 SET_FLOAT_WORD(t,0x3f800000 - (0x1000000>>k)); /* t=1-2^-k */ 110 y = t-(e-x); |
113 GET_FLOAT_WORD(i,y); 114 SET_FLOAT_WORD(y,i+(k<<23)); /* add k to y's exponent */ | 111 y = y*twopk; |
115 } else { | 112 } else { |
116 int32_t i; | |
117 SET_FLOAT_WORD(t,((0x7f-k)<<23)); /* 2^-k */ 118 y = x-(e+t); 119 y += one; | 113 SET_FLOAT_WORD(t,((0x7f-k)<<23)); /* 2^-k */ 114 y = x-(e+t); 115 y += one; |
120 GET_FLOAT_WORD(i,y); 121 SET_FLOAT_WORD(y,i+(k<<23)); /* add k to y's exponent */ | 116 y = y*twopk; |
122 } 123 } 124 return y; 125} | 117 } 118 } 119 return y; 120} |