diff options
author | Brian Jones <cbj@gnu.org> | 2001-11-05 02:56:46 +0000 |
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committer | Brian Jones <cbj@gnu.org> | 2001-11-05 02:56:46 +0000 |
commit | 936e6f9bd41e192e1ede500ef5aa26dd2a276ec0 (patch) | |
tree | 0c60a4db8f04045d08eb13e41dc8618931b68331 /native/fdlibm/e_exp.c | |
parent | cd15a52840b278df0d1171d691cac036db373d28 (diff) | |
download | classpath-936e6f9bd41e192e1ede500ef5aa26dd2a276ec0.tar.gz |
* native/jni/awt: renamed native/jni/gtk-peer
* native/jni/javaio.h: moved to native/jni/java-io
* native/jni/javaio.c: moved to native/jni/java-io
* native/jni/java_io_File.c: moved to native/jni/java-io
* native/jni/java_io_FileDescriptor.c: moved to native/jni/java-io
* native/jni/java_io_FileInputStream.c: moved to native/jni/java-io
* native/jni/java_io_FileOutputStream.c: moved to native/jni/java-io
* native/jni/java_io_ObjectInputStream.c: moved to native/jni/java-io
* native/jni/java_io_ObjectOutputStream.c: moved to native/jni/java-io
* native/jni/java_io_RandomAccessFile.c: moved to native/jni/java-io
* native/jni/javalang.h: moved to native/jni/java-lang
* native/jni/javalang.c: moved to native/jni/java-lang
* native/jni/java_lang_Double.c: moved to native/jni/java-lang
* native/jni/java_lang_Float.c: moved to native/jni/java-lang
* native/jni/java_lang_Object.c: moved to native/jni/java-lang
* native/jni/java_lang_System.c: moved to native/jni/java-lang
* native/jni/java_lang_reflect_Array.c: moved to native/jni/java-lang
* native/jni/javanet.h: moved to native/jni/java-net
* native/jni/javanet.c: moved to native/jni/java-net
* native/jni/java_net_InetAddress.c: moved to native/jni/java-net
* native/jni/java_net_PlainDatagramSocketImpl.c: moved to
native/jni/java-net
* native/jni/java_net_PlainSocketImpl.c: moved to native/jni/java-net
* native/jni/java_util_ResourceBundle.c: moved to native/jni/java-util
* native/jni/java_util_TimeZone.c: moved to native/jni/java-util
* native/jni/ieeefp.h: moved to native/jni/mprec
* native/jni/java-assert.h: moved to native/jni/mprec
* native/jni/mprec.c: moved to native/jni/mprec
* native/jni/mprec.h: moved to native/jni/mprec
* native/jni/acos.c: removed
* native/jni/asin.c: removed
* native/jni/atan2.c: removed
* native/jni/atan.c: removed
* native/jni/ceil.c: removed
* native/jni/cos.c: removed
* native/jni/dtoa.c: removed
* native/jni/e_fmod.c: removed
* native/jni/exp.c: removed
* native/jni/floor.c: removed
* native/jni/jcl.c: removed
* native/jni/jcl.h: removed
* native/jni/k_cos.c: removed
* native/jni/k_rem_pio2.c: removed
* native/jni/k_sin.c: removed
* native/jni/k_tan.c: removed
* native/jni/log.c: removed
* native/jni/pow.c: removed
* native/jni/remainder.c: removed
* native/jni/rint.c: removed
* native/jni/s_fabs.c: removed
* native/jni/sin.c: removed
* native/jni/sqrt.c: removed
* native/jni/tan.c: removed
* native/jni/fdlibm.h: removed
* native/jni/java_math_BigInteger.c: no longer needed
* native/fdlibm/dtoa.c: added from gcj to sync sources
* native/fdlibm/e_acos.c: added from gcj to sync sources
* native/fdlibm/e_asin.c: added from gcj to sync sources
* native/fdlibm/e_atan2.c: added from gcj to sync sources
* native/fdlibm/e_exp.c: added from gcj to sync sources
* native/fdlibm/e_fmod.c: added from gcj to sync sources
* native/fdlibm/e_log.c: added from gcj to sync sources
* native/fdlibm/e_pow.c: added from gcj to sync sources
* native/fdlibm/e_remainder.c: added from gcj to sync sources
* native/fdlibm/e_rem_pio2.c: added from gcj to sync sources
* native/fdlibm/e_scalb.c: added from gcj to sync sources
* native/fdlibm/e_sqrt.c: added from gcj to sync sources
* native/fdlibm/fdlibm.h: added from gcj to sync sources
* native/fdlibm/ieeefp.h: added from gcj to sync sources
* native/fdlibm/java-assert.h: added from gcj to sync sources
* native/fdlibm/k_cos.c: added from gcj to sync sources
* native/fdlibm/k_rem_pio2.c: added from gcj to sync sources
* native/fdlibm/k_sin.c: added from gcj to sync sources
* native/fdlibm/k_tan.c: added from gcj to sync sources
* native/fdlibm/mprec.c: added from gcj to sync sources
* native/fdlibm/mprec.h: added from gcj to sync sources
* native/fdlibm/s_atan.c: added from gcj to sync sources
* native/fdlibm/s_ceil.c: added from gcj to sync sources
* native/fdlibm/s_copysign.c: added from gcj to sync sources
* native/fdlibm/s_cos.c: added from gcj to sync sources
* native/fdlibm/s_fabs.c: added from gcj to sync sources
* native/fdlibm/sf_fabs.c: added from gcj to sync sources
* native/fdlibm/s_floor.c: added from gcj to sync sources
* native/fdlibm/sf_rint.c: added from gcj to sync sources
* native/fdlibm/s_rint.c: added from gcj to sync sources
* native/fdlibm/s_scalbn.c: added from gcj to sync sources
* native/fdlibm/s_sin.c: added from gcj to sync sources
* native/fdlibm/s_tan.c: added from gcj to sync sources
* native/fdlibm/strtod.c: added from gcj to sync sources
* native/fdlibm/w_acos.c: added from gcj to sync sources
* native/fdlibm/w_asin.c: added from gcj to sync sources
* native/fdlibm/w_atan2.c: added from gcj to sync sources
* native/fdlibm/w_exp.c: added from gcj to sync sources
* native/fdlibm/w_fmod.c: added from gcj to sync sources
* native/fdlibm/w_log.c: added from gcj to sync sources
* native/fdlibm/w_pow.c: added from gcj to sync sources
* native/fdlibm/w_remainder.c: added from gcj to sync sources
* native/fdlibm/w_sqrt.c: added from gcj to sync sources
* native/fdlibm/.cvsignore: new file
* native/jni/gtk-peer/Makefile.am: added -module to LDFLAGS
* native/jni/java-io/Makefile.am: added -module to LDFLAGS
* native/jni/java-io/.cvsignore: new file
* native/jni/java-lang/Makefile.am: added -module to LDFLAGS
* native/jni/java-lang/.cvsignore: new file
* native/jni/java-net/Makefile.am: added -module to LDFLAGS
* native/jni/java-net/.cvsignore: new file
* native/jni/java-util/Makefile.am: added -module to LDFLAGS
* native/jni/java-util/.cvsignore: new file
* native/fdlibm/Makefile.am: added -module to LDFLAGS
* native/jni/Makefile.am: removed rules, SUBDIRS equals java-io,
java-lang, java-net, java-util, gtk-peer
* native/Makefile.am: prepended fdlibm to SUBDIRS
* java/lang/Math.java static(): load libjavalang.so instead of
libjavalangmath.so
* java/math/BigInteger.java: replaced our native version with
pure Java implementation from gcj
* gnu/classpath/math: new directory
* gnu/classpath/math/MPN.java: new file from gcj, which came from Kawa,
and is included with permission from Per Bothner, the author.
* README: updated with current information about CVS and the
project
* THANKYOU: added Per Bothner
* TODO: updated with current information as I know it
* NEWS: updated with information about a 0.03 release
* HACKING: updated with new information
* INSTALL: updated with new information
* BUGS: added link to Savannah bug reporting page for the project
* ltconfig: removed due to upgrade of libtool to 1.4.2
* ltmain.sh: updated with libtool 1.4.2
* depcomp: new file from automake 1.5 upgrade
* configure.in: added to OUTPUT native/fdlibm/Makefile,
native/jni/java-io/Makefile, native/jni/java-lang/Makefile,
native/jni/java-net/Makefile, native/jni/java-util/Makefile,
native/jni/gtk-peer/Makefile
* install.sh: updated
* missing: updated
* mkinstalldirs: updated
* native/lib/Makefile.am: INCLUDES += changed to just INCLUDES = to
avoid automake warning
* native/lib/jcl.h: removed TRUE/FALSE #defines, added DBG
* native/nsa/: removed, files native_state.* moved to native/lib
* native/lib: renamed native/jni/classpath
* native/cni/Makefile.am: new file
* native/cni/.cvsignore: new file
* native/jni/gtk-peer/Makefile.am: LIBADD used to get native_state from
a common location
* native/jni/java-io/Makefile.am: LIBADD used to get jcl from a
common location, source modified to use relevant JCL_* functions
* native/jni/java-lang/Makefile.am: LIBADD used to get jcl from a
common location
* native/jni/java-net/Makefile.am: LIBADD used to get jcl from a common
location, source modified to use relevant JCL_* functions
* vm/reference/java/lang/Thread.java (Thread): wrongly marked private
constructor Thread (ThreadGroup, String) now public
* native/jni/java-util/java_util_ResourceBundle.c: removed file
* native/jni/java-util/Makefile.am: removed java_util_ResourceBundle.c
from library
Diffstat (limited to 'native/fdlibm/e_exp.c')
-rw-r--r-- | native/fdlibm/e_exp.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/native/fdlibm/e_exp.c b/native/fdlibm/e_exp.c new file mode 100644 index 000000000..e11ca8b38 --- /dev/null +++ b/native/fdlibm/e_exp.c @@ -0,0 +1,167 @@ + +/* @(#)e_exp.c 5.1 93/09/24 */ +/* + * ==================================================== + * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. + * + * Developed at SunPro, a Sun Microsystems, Inc. business. + * Permission to use, copy, modify, and distribute this + * software is freely granted, provided that this notice + * is preserved. + * ==================================================== + */ + +/* __ieee754_exp(x) + * Returns the exponential of x. + * + * Method + * 1. Argument reduction: + * Reduce x to an r so that |r| <= 0.5*ln2 ~ 0.34658. + * Given x, find r and integer k such that + * + * x = k*ln2 + r, |r| <= 0.5*ln2. + * + * Here r will be represented as r = hi-lo for better + * accuracy. + * + * 2. Approximation of exp(r) by a special rational function on + * the interval [0,0.34658]: + * Write + * R(r**2) = r*(exp(r)+1)/(exp(r)-1) = 2 + r*r/6 - r**4/360 + ... + * We use a special Reme algorithm on [0,0.34658] to generate + * a polynomial of degree 5 to approximate R. The maximum error + * of this polynomial approximation is bounded by 2**-59. In + * other words, + * R(z) ~ 2.0 + P1*z + P2*z**2 + P3*z**3 + P4*z**4 + P5*z**5 + * (where z=r*r, and the values of P1 to P5 are listed below) + * and + * | 5 | -59 + * | 2.0+P1*z+...+P5*z - R(z) | <= 2 + * | | + * The computation of exp(r) thus becomes + * 2*r + * exp(r) = 1 + ------- + * R - r + * r*R1(r) + * = 1 + r + ----------- (for better accuracy) + * 2 - R1(r) + * where + * 2 4 10 + * R1(r) = r - (P1*r + P2*r + ... + P5*r ). + * + * 3. Scale back to obtain exp(x): + * From step 1, we have + * exp(x) = 2^k * exp(r) + * + * Special cases: + * exp(INF) is INF, exp(NaN) is NaN; + * exp(-INF) is 0, and + * for finite argument, only exp(0)=1 is exact. + * + * Accuracy: + * according to an error analysis, the error is always less than + * 1 ulp (unit in the last place). + * + * Misc. info. + * For IEEE double + * if x > 7.09782712893383973096e+02 then exp(x) overflow + * if x < -7.45133219101941108420e+02 then exp(x) underflow + * + * Constants: + * The hexadecimal values are the intended ones for the following + * constants. The decimal values may be used, provided that the + * compiler will convert from decimal to binary accurately enough + * to produce the hexadecimal values shown. + */ + +#include "fdlibm.h" + +#ifndef _DOUBLE_IS_32BITS + +#ifdef __STDC__ +static const double +#else +static double +#endif +one = 1.0, +halF[2] = {0.5,-0.5,}, +huge = 1.0e+300, +twom1000= 9.33263618503218878990e-302, /* 2**-1000=0x01700000,0*/ +o_threshold= 7.09782712893383973096e+02, /* 0x40862E42, 0xFEFA39EF */ +u_threshold= -7.45133219101941108420e+02, /* 0xc0874910, 0xD52D3051 */ +ln2HI[2] ={ 6.93147180369123816490e-01, /* 0x3fe62e42, 0xfee00000 */ + -6.93147180369123816490e-01,},/* 0xbfe62e42, 0xfee00000 */ +ln2LO[2] ={ 1.90821492927058770002e-10, /* 0x3dea39ef, 0x35793c76 */ + -1.90821492927058770002e-10,},/* 0xbdea39ef, 0x35793c76 */ +invln2 = 1.44269504088896338700e+00, /* 0x3ff71547, 0x652b82fe */ +P1 = 1.66666666666666019037e-01, /* 0x3FC55555, 0x5555553E */ +P2 = -2.77777777770155933842e-03, /* 0xBF66C16C, 0x16BEBD93 */ +P3 = 6.61375632143793436117e-05, /* 0x3F11566A, 0xAF25DE2C */ +P4 = -1.65339022054652515390e-06, /* 0xBEBBBD41, 0xC5D26BF1 */ +P5 = 4.13813679705723846039e-08; /* 0x3E663769, 0x72BEA4D0 */ + + +#ifdef __STDC__ + double __ieee754_exp(double x) /* default IEEE double exp */ +#else + double __ieee754_exp(x) /* default IEEE double exp */ + double x; +#endif +{ + double y,hi,lo,c,t; + int32_t k,xsb; + uint32_t hx; + + GET_HIGH_WORD(hx,x); + xsb = (hx>>31)&1; /* sign bit of x */ + hx &= 0x7fffffff; /* high word of |x| */ + + /* filter out non-finite argument */ + if(hx >= 0x40862E42) { /* if |x|>=709.78... */ + if(hx>=0x7ff00000) { + uint32_t lx; + GET_LOW_WORD(lx,x); + if(((hx&0xfffff)|lx)!=0) + return x+x; /* NaN */ + else return (xsb==0)? x:0.0; /* exp(+-inf)={inf,0} */ + } + if(x > o_threshold) return huge*huge; /* overflow */ + if(x < u_threshold) return twom1000*twom1000; /* underflow */ + } + + /* argument reduction */ + if(hx > 0x3fd62e42) { /* if |x| > 0.5 ln2 */ + if(hx < 0x3FF0A2B2) { /* and |x| < 1.5 ln2 */ + hi = x-ln2HI[xsb]; lo=ln2LO[xsb]; k = 1-xsb-xsb; + } else { + k = invln2*x+halF[xsb]; + t = k; + hi = x - t*ln2HI[0]; /* t*ln2HI is exact here */ + lo = t*ln2LO[0]; + } + x = hi - lo; + } + else if(hx < 0x3e300000) { /* when |x|<2**-28 */ + if(huge+x>one) return one+x;/* trigger inexact */ + } + else k = 0; + + /* x is now in primary range */ + t = x*x; + c = x - t*(P1+t*(P2+t*(P3+t*(P4+t*P5)))); + if(k==0) return one-((x*c)/(c-2.0)-x); + else y = one-((lo-(x*c)/(2.0-c))-hi); + if(k >= -1021) { + uint32_t hy; + GET_HIGH_WORD(hy,y); + SET_HIGH_WORD(y,hy+(k<<20)); /* add k to y's exponent */ + return y; + } else { + uint32_t hy; + GET_HIGH_WORD(hy,y); + SET_HIGH_WORD(y,hy+((k+1000)<<20)); /* add k to y's exponent */ + return y*twom1000; + } +} + +#endif /* defined(_DOUBLE_IS_32BITS) */ |