jdk-sandbox: comparison hotspot/src/share/vm/runtime/sharedRuntimeTrans.cpp

equal deleted inserted replaced

-:fd16c54261b3
+:489c9b5090e2
+/*
+* Copyright 2005 Sun Microsystems, Inc.  All Rights Reserved.
+* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+*
+* This code is free software; you can redistribute it and/or modify it
+* under the terms of the GNU General Public License version 2 only, as
+* published by the Free Software Foundation.
+*
+* This code is distributed in the hope that it will be useful, but WITHOUT
+* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+* FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+* version 2 for more details (a copy is included in the LICENSE file that
+* accompanied this code).
+*
+* You should have received a copy of the GNU General Public License version
+* 2 along with this work; if not, write to the Free Software Foundation,
+* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+*
+* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+* CA 95054 USA or visit www.sun.com if you need additional information or
+* have any questions.
+*
+*/
+#include "incls/_precompiled.incl"
+#include "incls/_sharedRuntimeTrans.cpp.incl"
+// This file contains copies of the fdlibm routines used by
+// StrictMath. It turns out that it is almost always required to use
+// these runtime routines; the Intel CPU doesn't meet the Java
+// specification for sin/cos outside a certain limited argument range,
+// and the SPARC CPU doesn't appear to have sin/cos instructions. It
+// also turns out that avoiding the indirect call through function
+// pointer out to libjava.so in SharedRuntime speeds these routines up
+// by roughly 15% on both Win32/x86 and Solaris/SPARC.
+// Enabling optimizations in this file causes incorrect code to be
+// generated; can not figure out how to turn down optimization for one
+// file in the IDE on Windows
+#ifdef WIN32
+# pragma optimize ( "", off )
+#endif
+#include <math.h>
+// VM_LITTLE_ENDIAN is #defined appropriately in the Makefiles
+// [jk] this is not 100% correct because the float word order may different
+// from the byte order (e.g. on ARM)
+#ifdef VM_LITTLE_ENDIAN
+# define __HI(x) *(1+(int*)&x)
+# define __LO(x) *(int*)&x
+#else
+# define __HI(x) *(int*)&x
+# define __LO(x) *(1+(int*)&x)
+#endif
+double copysign(double x, double y) {
+__HI(x) = (__HI(x)&0x7fffffff)|(__HI(y)&0x80000000);
+return x;
+}
+/*
+* ====================================================
+* Copyright (C) 1998 by Sun Microsystems, Inc. All rights reserved.
+*
+* Developed at SunSoft, a Sun Microsystems, Inc. business.
+* Permission to use, copy, modify, and distribute this
+* software is freely granted, provided that this notice
+* is preserved.
+* ====================================================
+*/
+/*
+* scalbn (double x, int n)
+* scalbn(x,n) returns x* 2**n  computed by  exponent
+* manipulation rather than by actually performing an
+* exponentiation or a multiplication.
+*/
+static const double
+two54   =  1.80143985094819840000e+16, /* 0x43500000, 0x00000000 */
+twom54  =  5.55111512312578270212e-17, /* 0x3C900000, 0x00000000 */
+hugeX   = 1.0e+300,
+tiny   = 1.0e-300;
+double scalbn (double x, int n) {
+int  k,hx,lx;
+hx = __HI(x);
+lx = __LO(x);
+k = (hx&0x7ff00000)>>20;              /* extract exponent */
+if (k==0) {                           /* 0 or subnormal x */
+if ((lx|(hx&0x7fffffff))==0) return x; /* +-0 */
+x *= two54;
+hx = __HI(x);
+k = ((hx&0x7ff00000)>>20) - 54;
+if (n< -50000) return tiny*x;       /*underflow*/
+}
+if (k==0x7ff) return x+x;             /* NaN or Inf */
+k = k+n;
+if (k >  0x7fe) return hugeX*copysign(hugeX,x); /* overflow  */
+if (k > 0)                            /* normal result */
+{__HI(x) = (hx&0x800fffff)|(k<<20); return x;}
+if (k <= -54) {
+if (n > 50000)      /* in case integer overflow in n+k */
+return hugeX*copysign(hugeX,x);   /*overflow*/
+else return tiny*copysign(tiny,x);  /*underflow*/
+}
+k += 54;                              /* subnormal result */
+__HI(x) = (hx&0x800fffff)|(k<<20);
+return x*twom54;
+}
+/* __ieee754_log(x)
+* Return the logrithm of x
+*
+* Method :
+*   1. Argument Reduction: find k and f such that
+*                    x = 2^k * (1+f),
+*       where  sqrt(2)/2 < 1+f < sqrt(2) .
+*
+*   2. Approximation of log(1+f).
+*    Let s = f/(2+f) ; based on log(1+f) = log(1+s) - log(1-s)
+*             = 2s + 2/3 s**3 + 2/5 s**5 + .....,
+*             = 2s + s*R
+*      We use a special Reme algorithm on [0,0.1716] to generate
+*    a polynomial of degree 14 to approximate R The maximum error
+*    of this polynomial approximation is bounded by 2**-58.45. In
+*    other words,
+*                    2      4      6      8      10      12      14
+*        R(z) ~ Lg1*s +Lg2*s +Lg3*s +Lg4*s +Lg5*s  +Lg6*s  +Lg7*s
+*    (the values of Lg1 to Lg7 are listed in the program)
+*    and
+*        |      2          14          |     -58.45
+*        | Lg1*s +...+Lg7*s    -  R(z) | <= 2
+*        |                             |
+*    Note that 2s = f - s*f = f - hfsq + s*hfsq, where hfsq = f*f/2.
+*    In order to guarantee error in log below 1ulp, we compute log
+*    by
+*            log(1+f) = f - s*(f - R)        (if f is not too large)
+*            log(1+f) = f - (hfsq - s*(hfsq+R)).     (better accuracy)
+*
+*    3. Finally,  log(x) = k*ln2 + log(1+f).
+*                        = k*ln2_hi+(f-(hfsq-(s*(hfsq+R)+k*ln2_lo)))
+*       Here ln2 is split into two floating point number:
+*                    ln2_hi + ln2_lo,
+*       where n*ln2_hi is always exact for |n| < 2000.
+*
+* Special cases:
+*    log(x) is NaN with signal if x < 0 (including -INF) ;
+*    log(+INF) is +INF; log(0) is -INF with signal;
+*    log(NaN) is that NaN with no signal.
+*
+* Accuracy:
+*    according to an error analysis, the error is always less than
+*    1 ulp (unit in the last place).
+*
+* 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.
+*/
+static const double
+ln2_hi  =  6.93147180369123816490e-01,        /* 3fe62e42 fee00000 */
+ln2_lo  =  1.90821492927058770002e-10,        /* 3dea39ef 35793c76 */
+Lg1 = 6.666666666666735130e-01,  /* 3FE55555 55555593 */
+Lg2 = 3.999999999940941908e-01,  /* 3FD99999 9997FA04 */
+Lg3 = 2.857142874366239149e-01,  /* 3FD24924 94229359 */
+Lg4 = 2.222219843214978396e-01,  /* 3FCC71C5 1D8E78AF */
+Lg5 = 1.818357216161805012e-01,  /* 3FC74664 96CB03DE */
+Lg6 = 1.531383769920937332e-01,  /* 3FC39A09 D078C69F */
+Lg7 = 1.479819860511658591e-01;  /* 3FC2F112 DF3E5244 */
+static double zero = 0.0;
+static double __ieee754_log(double x) {
+double hfsq,f,s,z,R,w,t1,t2,dk;
+int k,hx,i,j;
+unsigned lx;
+hx = __HI(x);               /* high word of x */
+lx = __LO(x);               /* low  word of x */
+k=0;
+if (hx < 0x00100000) {                   /* x < 2**-1022  */
+if (((hx&0x7fffffff)|lx)==0)
+return -two54/zero;             /* log(+-0)=-inf */
+if (hx<0) return (x-x)/zero;   /* log(-#) = NaN */
+k -= 54; x *= two54; /* subnormal number, scale up x */
+hx = __HI(x);             /* high word of x */
+}
+if (hx >= 0x7ff00000) return x+x;
+k += (hx>>20)-1023;
+hx &= 0x000fffff;
+i = (hx+0x95f64)&0x100000;
+__HI(x) = hx|(i^0x3ff00000);        /* normalize x or x/2 */
+k += (i>>20);
+f = x-1.0;
+if((0x000fffff&(2+hx))<3) {  /* |f| < 2**-20 */
+if(f==zero) {
+if (k==0) return zero;
+else {dk=(double)k; return dk*ln2_hi+dk*ln2_lo;}
+}
+R = f*f*(0.5-0.33333333333333333*f);
+if(k==0) return f-R; else {dk=(double)k;
+return dk*ln2_hi-((R-dk*ln2_lo)-f);}
+}
+s = f/(2.0+f);
+dk = (double)k;
+z = s*s;
+i = hx-0x6147a;
+w = z*z;
+j = 0x6b851-hx;
+t1= w*(Lg2+w*(Lg4+w*Lg6));
+t2= z*(Lg1+w*(Lg3+w*(Lg5+w*Lg7)));
+i |= j;
+R = t2+t1;
+if(i>0) {
+hfsq=0.5*f*f;
+if(k==0) return f-(hfsq-s*(hfsq+R)); else
+return dk*ln2_hi-((hfsq-(s*(hfsq+R)+dk*ln2_lo))-f);
+} else {
+if(k==0) return f-s*(f-R); else
+return dk*ln2_hi-((s*(f-R)-dk*ln2_lo)-f);
+}
+}
+JRT_LEAF(jdouble, SharedRuntime::dlog(jdouble x))
+return __ieee754_log(x);
+JRT_END
+/* __ieee754_log10(x)
+* Return the base 10 logarithm of x
+*
+* Method :
+*    Let log10_2hi = leading 40 bits of log10(2) and
+*        log10_2lo = log10(2) - log10_2hi,
+*        ivln10   = 1/log(10) rounded.
+*    Then
+*            n = ilogb(x),
+*            if(n<0)  n = n+1;
+*            x = scalbn(x,-n);
+*            log10(x) := n*log10_2hi + (n*log10_2lo + ivln10*log(x))
+*
+* Note 1:
+*    To guarantee log10(10**n)=n, where 10**n is normal, the rounding
+*    mode must set to Round-to-Nearest.
+* Note 2:
+*    [1/log(10)] rounded to 53 bits has error  .198   ulps;
+*    log10 is monotonic at all binary break points.
+*
+* Special cases:
+*    log10(x) is NaN with signal if x < 0;
+*    log10(+INF) is +INF with no signal; log10(0) is -INF with signal;
+*    log10(NaN) is that NaN with no signal;
+*    log10(10**N) = N  for N=0,1,...,22.
+*
+* 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.
+*/
+static const double
+ivln10     =  4.34294481903251816668e-01, /* 0x3FDBCB7B, 0x1526E50E */
+log10_2hi  =  3.01029995663611771306e-01, /* 0x3FD34413, 0x509F6000 */
+log10_2lo  =  3.69423907715893078616e-13; /* 0x3D59FEF3, 0x11F12B36 */
+static double __ieee754_log10(double x) {
+double y,z;
+int i,k,hx;
+unsigned lx;
+hx = __HI(x);       /* high word of x */
+lx = __LO(x);       /* low word of x */
+k=0;
+if (hx < 0x00100000) {                  /* x < 2**-1022  */
+if (((hx&0x7fffffff)|lx)==0)
+return -two54/zero;             /* log(+-0)=-inf */
+if (hx<0) return (x-x)/zero;        /* log(-#) = NaN */
+k -= 54; x *= two54; /* subnormal number, scale up x */
+hx = __HI(x);                /* high word of x */
+}
+if (hx >= 0x7ff00000) return x+x;
+k += (hx>>20)-1023;
+i  = ((unsigned)k&0x80000000)>>31;
+hx = (hx&0x000fffff)|((0x3ff-i)<<20);
+y  = (double)(k+i);
+__HI(x) = hx;
+z  = y*log10_2lo + ivln10*__ieee754_log(x);
+return  z+y*log10_2hi;
+}
+JRT_LEAF(jdouble, SharedRuntime::dlog10(jdouble x))
+return __ieee754_log10(x);
+JRT_END
+/* __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.
+*/
+static const double
+one     = 1.0,
+halF[2]       = {0.5,-0.5,},
+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 */
+static double __ieee754_exp(double x) {
+double y,hi=0,lo=0,c,t;
+int k=0,xsb;
+unsigned hx;
+hx  = __HI(x);        /* high word of 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) {
+if(((hx&0xfffff)|__LO(x))!=0)
+return x+x;             /* NaN */
+else return (xsb==0)? x:0.0;      /* exp(+-inf)={inf,0} */
+}
+if(x > o_threshold) return hugeX*hugeX; /* 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  = (int)(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(hugeX+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) {
+__HI(y) += (k<<20); /* add k to y's exponent */
+return y;
+} else {
+__HI(y) += ((k+1000)<<20);/* add k to y's exponent */
+return y*twom1000;
+}
+}
+JRT_LEAF(jdouble, SharedRuntime::dexp(jdouble x))
+return __ieee754_exp(x);
+JRT_END
+/* __ieee754_pow(x,y) return x**y
+*
+*                    n
+* Method:  Let x =  2   * (1+f)
+*      1. Compute and return log2(x) in two pieces:
+*              log2(x) = w1 + w2,
+*         where w1 has 53-24 = 29 bit trailing zeros.
+*      2. Perform y*log2(x) = n+y' by simulating muti-precision
+*         arithmetic, where |y'|<=0.5.
+*      3. Return x**y = 2**n*exp(y'*log2)
+*
+* Special cases:
+*      1.  (anything) ** 0  is 1
+*      2.  (anything) ** 1  is itself
+*      3.  (anything) ** NAN is NAN
+*      4.  NAN ** (anything except 0) is NAN
+*      5.  +-(|x| > 1) **  +INF is +INF
+*      6.  +-(|x| > 1) **  -INF is +0
+*      7.  +-(|x| < 1) **  +INF is +0
+*      8.  +-(|x| < 1) **  -INF is +INF
+*      9.  +-1         ** +-INF is NAN
+*      10. +0 ** (+anything except 0, NAN)               is +0
+*      11. -0 ** (+anything except 0, NAN, odd integer)  is +0
+*      12. +0 ** (-anything except 0, NAN)               is +INF
+*      13. -0 ** (-anything except 0, NAN, odd integer)  is +INF
+*      14. -0 ** (odd integer) = -( +0 ** (odd integer) )
+*      15. +INF ** (+anything except 0,NAN) is +INF
+*      16. +INF ** (-anything except 0,NAN) is +0
+*      17. -INF ** (anything)  = -0 ** (-anything)
+*      18. (-anything) ** (integer) is (-1)**(integer)*(+anything**integer)
+*      19. (-anything except 0 and inf) ** (non-integer) is NAN
+*
+* Accuracy:
+*      pow(x,y) returns x**y nearly rounded. In particular
+*                      pow(integer,integer)
+*      always returns the correct integer provided it is
+*      representable.
+*
+* 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.
+*/
+static const double
+bp[] = {1.0, 1.5,},
+dp_h[] = { 0.0, 5.84962487220764160156e-01,}, /* 0x3FE2B803, 0x40000000 */
+dp_l[] = { 0.0, 1.35003920212974897128e-08,}, /* 0x3E4CFDEB, 0x43CFD006 */
+zeroX    =  0.0,
+two     =  2.0,
+two53   =  9007199254740992.0,  /* 0x43400000, 0x00000000 */
+/* poly coefs for (3/2)*(log(x)-2s-2/3*s**3 */
+L1X  =  5.99999999999994648725e-01, /* 0x3FE33333, 0x33333303 */
+L2X  =  4.28571428578550184252e-01, /* 0x3FDB6DB6, 0xDB6FABFF */
+L3X  =  3.33333329818377432918e-01, /* 0x3FD55555, 0x518F264D */
+L4X  =  2.72728123808534006489e-01, /* 0x3FD17460, 0xA91D4101 */
+L5X  =  2.30660745775561754067e-01, /* 0x3FCD864A, 0x93C9DB65 */
+L6X  =  2.06975017800338417784e-01, /* 0x3FCA7E28, 0x4A454EEF */
+lg2  =  6.93147180559945286227e-01, /* 0x3FE62E42, 0xFEFA39EF */
+lg2_h  =  6.93147182464599609375e-01, /* 0x3FE62E43, 0x00000000 */
+lg2_l  = -1.90465429995776804525e-09, /* 0xBE205C61, 0x0CA86C39 */
+ovt =  8.0085662595372944372e-0017, /* -(1024-log2(ovfl+.5ulp)) */
+cp    =  9.61796693925975554329e-01, /* 0x3FEEC709, 0xDC3A03FD =2/(3ln2) */
+cp_h  =  9.61796700954437255859e-01, /* 0x3FEEC709, 0xE0000000 =(float)cp */
+cp_l  = -7.02846165095275826516e-09, /* 0xBE3E2FE0, 0x145B01F5 =tail of cp_h*/
+ivln2    =  1.44269504088896338700e+00, /* 0x3FF71547, 0x652B82FE =1/ln2 */
+ivln2_h  =  1.44269502162933349609e+00, /* 0x3FF71547, 0x60000000 =24b 1/ln2*/
+ivln2_l  =  1.92596299112661746887e-08; /* 0x3E54AE0B, 0xF85DDF44 =1/ln2 tail*/
+double __ieee754_pow(double x, double y) {
+double z,ax,z_h,z_l,p_h,p_l;
+double y1,t1,t2,r,s,t,u,v,w;
+int i0,i1,i,j,k,yisint,n;
+int hx,hy,ix,iy;
+unsigned lx,ly;
+i0 = ((*(int*)&one)>>29)^1; i1=1-i0;
+hx = __HI(x); lx = __LO(x);
+hy = __HI(y); ly = __LO(y);
+ix = hx&0x7fffffff;  iy = hy&0x7fffffff;
+/* y==zero: x**0 = 1 */
+if((iy|ly)==0) return one;
+/* +-NaN return x+y */
+if(ix > 0x7ff00000 || ((ix==0x7ff00000)&&(lx!=0)) ||
+iy > 0x7ff00000 || ((iy==0x7ff00000)&&(ly!=0)))
+return x+y;
+/* determine if y is an odd int when x < 0
+* yisint = 0 ... y is not an integer
+* yisint = 1 ... y is an odd int
+* yisint = 2 ... y is an even int
+*/
+yisint  = 0;
+if(hx<0) {
+if(iy>=0x43400000) yisint = 2; /* even integer y */
+else if(iy>=0x3ff00000) {
+k = (iy>>20)-0x3ff;          /* exponent */
+if(k>20) {
+j = ly>>(52-k);
+if((unsigned)(j<<(52-k))==ly) yisint = 2-(j&1);
+} else if(ly==0) {
+j = iy>>(20-k);
+if((j<<(20-k))==iy) yisint = 2-(j&1);
+}
+}
+}
+/* special value of y */
+if(ly==0) {
+if (iy==0x7ff00000) {       /* y is +-inf */
+if(((ix-0x3ff00000)|lx)==0)
+return  y - y;  /* inf**+-1 is NaN */
+else if (ix >= 0x3ff00000)/* (|x|>1)**+-inf = inf,0 */
+return (hy>=0)? y: zeroX;
+else                      /* (|x|<1)**-,+inf = inf,0 */
+return (hy<0)?-y: zeroX;
+}
+if(iy==0x3ff00000) {        /* y is  +-1 */
+if(hy<0) return one/x; else return x;
+}
+if(hy==0x40000000) return x*x; /* y is  2 */
+if(hy==0x3fe00000) {        /* y is  0.5 */
+if(hx>=0) /* x >= +0 */
+return sqrt(x);
+}
+}
+ax   = fabsd(x);
+/* special value of x */
+if(lx==0) {
+if(ix==0x7ff00000||ix==0||ix==0x3ff00000){
+z = ax;                   /*x is +-0,+-inf,+-1*/
+if(hy<0) z = one/z;       /* z = (1/|x|) */
+if(hx<0) {
+if(((ix-0x3ff00000)|yisint)==0) {
+z = (z-z)/(z-z); /* (-1)**non-int is NaN */
+} else if(yisint==1)
+z = -1.0*z;           /* (x<0)**odd = -(|x|**odd) */
+}
+return z;
+}
+}
+n = (hx>>31)+1;
+/* (x<0)**(non-int) is NaN */
+if((n|yisint)==0) return (x-x)/(x-x);
+s = one; /* s (sign of result -ve**odd) = -1 else = 1 */
+if((n|(yisint-1))==0) s = -one;/* (-ve)**(odd int) */
+/* |y| is huge */
+if(iy>0x41e00000) { /* if |y| > 2**31 */
+if(iy>0x43f00000){  /* if |y| > 2**64, must o/uflow */
+if(ix<=0x3fefffff) return (hy<0)? hugeX*hugeX:tiny*tiny;
+if(ix>=0x3ff00000) return (hy>0)? hugeX*hugeX:tiny*tiny;
+}
+/* over/underflow if x is not close to one */
+if(ix<0x3fefffff) return (hy<0)? s*hugeX*hugeX:s*tiny*tiny;
+if(ix>0x3ff00000) return (hy>0)? s*hugeX*hugeX:s*tiny*tiny;
+/* now |1-x| is tiny <= 2**-20, suffice to compute
+log(x) by x-x^2/2+x^3/3-x^4/4 */
+t = ax-one;         /* t has 20 trailing zeros */
+w = (t*t)*(0.5-t*(0.3333333333333333333333-t*0.25));
+u = ivln2_h*t;      /* ivln2_h has 21 sig. bits */
+v = t*ivln2_l-w*ivln2;
+t1 = u+v;
+__LO(t1) = 0;
+t2 = v-(t1-u);
+} else {
+double ss,s2,s_h,s_l,t_h,t_l;
+n = 0;
+/* take care subnormal number */
+if(ix<0x00100000)
+{ax *= two53; n -= 53; ix = __HI(ax); }
+n  += ((ix)>>20)-0x3ff;
+j  = ix&0x000fffff;
+/* determine interval */
+ix = j|0x3ff00000;          /* normalize ix */
+if(j<=0x3988E) k=0;         /* |x|<sqrt(3/2) */
+else if(j<0xBB67A) k=1;     /* |x|<sqrt(3)   */
+else {k=0;n+=1;ix -= 0x00100000;}
+__HI(ax) = ix;
+/* compute ss = s_h+s_l = (x-1)/(x+1) or (x-1.5)/(x+1.5) */
+u = ax-bp[k];               /* bp[0]=1.0, bp[1]=1.5 */
+v = one/(ax+bp[k]);
+ss = u*v;
+s_h = ss;
+__LO(s_h) = 0;
+/* t_h=ax+bp[k] High */
+t_h = zeroX;
+__HI(t_h)=((ix>>1)|0x20000000)+0x00080000+(k<<18);
+t_l = ax - (t_h-bp[k]);
+s_l = v*((u-s_h*t_h)-s_h*t_l);
+/* compute log(ax) */
+s2 = ss*ss;
+r = s2*s2*(L1X+s2*(L2X+s2*(L3X+s2*(L4X+s2*(L5X+s2*L6X)))));
+r += s_l*(s_h+ss);
+s2  = s_h*s_h;
+t_h = 3.0+s2+r;
+__LO(t_h) = 0;
+t_l = r-((t_h-3.0)-s2);
+/* u+v = ss*(1+...) */
+u = s_h*t_h;
+v = s_l*t_h+t_l*ss;
+/* 2/(3log2)*(ss+...) */
+p_h = u+v;
+__LO(p_h) = 0;
+p_l = v-(p_h-u);
+z_h = cp_h*p_h;             /* cp_h+cp_l = 2/(3*log2) */
+z_l = cp_l*p_h+p_l*cp+dp_l[k];
+/* log2(ax) = (ss+..)*2/(3*log2) = n + dp_h + z_h + z_l */
+t = (double)n;
+t1 = (((z_h+z_l)+dp_h[k])+t);
+__LO(t1) = 0;
+t2 = z_l-(((t1-t)-dp_h[k])-z_h);
+}
+/* split up y into y1+y2 and compute (y1+y2)*(t1+t2) */
+y1  = y;
+__LO(y1) = 0;
+p_l = (y-y1)*t1+y*t2;
+p_h = y1*t1;
+z = p_l+p_h;
+j = __HI(z);
+i = __LO(z);
+if (j>=0x40900000) {                          /* z >= 1024 */
+if(((j-0x40900000)|i)!=0)                   /* if z > 1024 */
+return s*hugeX*hugeX;                     /* overflow */
+else {
+if(p_l+ovt>z-p_h) return s*hugeX*hugeX;   /* overflow */
+}
+} else if((j&0x7fffffff)>=0x4090cc00 ) {      /* z <= -1075 */
+if(((j-0xc090cc00)|i)!=0)           /* z < -1075 */
+return s*tiny*tiny;               /* underflow */
+else {
+if(p_l<=z-p_h) return s*tiny*tiny;        /* underflow */
+}
+}
+/*
+* compute 2**(p_h+p_l)
+*/
+i = j&0x7fffffff;
+k = (i>>20)-0x3ff;
+n = 0;
+if(i>0x3fe00000) {            /* if |z| > 0.5, set n = [z+0.5] */
+n = j+(0x00100000>>(k+1));
+k = ((n&0x7fffffff)>>20)-0x3ff;     /* new k for n */
+t = zeroX;
+__HI(t) = (n&~(0x000fffff>>k));
+n = ((n&0x000fffff)|0x00100000)>>(20-k);
+if(j<0) n = -n;
+p_h -= t;
+}
+t = p_l+p_h;
+__LO(t) = 0;
+u = t*lg2_h;
+v = (p_l-(t-p_h))*lg2+t*lg2_l;
+z = u+v;
+w = v-(z-u);
+t  = z*z;
+t1  = z - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))));
+r  = (z*t1)/(t1-two)-(w+z*w);
+z  = one-(r-z);
+j  = __HI(z);
+j += (n<<20);
+if((j>>20)<=0) z = scalbn(z,n);       /* subnormal output */
+else __HI(z) += (n<<20);
+return s*z;
+}
+JRT_LEAF(jdouble, SharedRuntime::dpow(jdouble x, jdouble y))
+return __ieee754_pow(x, y);
+JRT_END
+#ifdef WIN32
+# pragma optimize ( "", on )
+#endif

changeset 1	489c9b5090e2
child 5547	f4b087cbb361