src/hotspot/share/runtime/sharedRuntimeTrans.cpp
author erikj
Tue, 12 Sep 2017 19:03:39 +0200
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parent 25919 hotspot/src/share/vm/runtime/sharedRuntimeTrans.cpp@d4e4f72b49fc
child 47659 a8e9aff89f7b
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8187443: Forest Consolidation: Move files to unified layout Reviewed-by: darcy, ihse
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/*
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 * Copyright (c) 2005, 2014, Oracle and/or its affiliates. All rights reserved.
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * This code is free software; you can redistribute it and/or modify it
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 * under the terms of the GNU General Public License version 2 only, as
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 * published by the Free Software Foundation.
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 *
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 * This code is distributed in the hope that it will be useful, but WITHOUT
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * version 2 for more details (a copy is included in the LICENSE file that
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 * accompanied this code).
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 *
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 * You should have received a copy of the GNU General Public License version
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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 *
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 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 * or visit www.oracle.com if you need additional information or have any
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 * questions.
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 *
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 */
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#include "precompiled.hpp"
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#include "prims/jni.h"
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#include "runtime/interfaceSupport.hpp"
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#include "runtime/sharedRuntime.hpp"
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// This file contains copies of the fdlibm routines used by
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// StrictMath. It turns out that it is almost always required to use
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// these runtime routines; the Intel CPU doesn't meet the Java
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// specification for sin/cos outside a certain limited argument range,
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// and the SPARC CPU doesn't appear to have sin/cos instructions. It
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// also turns out that avoiding the indirect call through function
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// pointer out to libjava.so in SharedRuntime speeds these routines up
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// by roughly 15% on both Win32/x86 and Solaris/SPARC.
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// Enabling optimizations in this file causes incorrect code to be
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// generated; can not figure out how to turn down optimization for one
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// file in the IDE on Windows
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#ifdef WIN32
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# pragma warning( disable: 4748 ) // /GS can not protect parameters and local variables from local buffer overrun because optimizations are disabled in function
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# pragma optimize ( "", off )
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#endif
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#include "runtime/sharedRuntimeMath.hpp"
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/* __ieee754_log(x)
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 * Return the logarithm of x
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 *
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 * Method :
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 *   1. Argument Reduction: find k and f such that
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 *                    x = 2^k * (1+f),
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 *       where  sqrt(2)/2 < 1+f < sqrt(2) .
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 *
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 *   2. Approximation of log(1+f).
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 *    Let s = f/(2+f) ; based on log(1+f) = log(1+s) - log(1-s)
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 *             = 2s + 2/3 s**3 + 2/5 s**5 + .....,
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 *             = 2s + s*R
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 *      We use a special Reme algorithm on [0,0.1716] to generate
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 *    a polynomial of degree 14 to approximate R The maximum error
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 *    of this polynomial approximation is bounded by 2**-58.45. In
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 *    other words,
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 *                    2      4      6      8      10      12      14
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 *        R(z) ~ Lg1*s +Lg2*s +Lg3*s +Lg4*s +Lg5*s  +Lg6*s  +Lg7*s
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 *    (the values of Lg1 to Lg7 are listed in the program)
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 *    and
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 *        |      2          14          |     -58.45
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 *        | Lg1*s +...+Lg7*s    -  R(z) | <= 2
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 *        |                             |
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 *    Note that 2s = f - s*f = f - hfsq + s*hfsq, where hfsq = f*f/2.
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 *    In order to guarantee error in log below 1ulp, we compute log
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 *    by
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 *            log(1+f) = f - s*(f - R)        (if f is not too large)
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 *            log(1+f) = f - (hfsq - s*(hfsq+R)).     (better accuracy)
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 *
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 *    3. Finally,  log(x) = k*ln2 + log(1+f).
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 *                        = k*ln2_hi+(f-(hfsq-(s*(hfsq+R)+k*ln2_lo)))
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 *       Here ln2 is split into two floating point number:
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 *                    ln2_hi + ln2_lo,
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 *       where n*ln2_hi is always exact for |n| < 2000.
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 *
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 * Special cases:
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 *    log(x) is NaN with signal if x < 0 (including -INF) ;
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 *    log(+INF) is +INF; log(0) is -INF with signal;
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 *    log(NaN) is that NaN with no signal.
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 *
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 * Accuracy:
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 *    according to an error analysis, the error is always less than
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 *    1 ulp (unit in the last place).
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 *
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 * Constants:
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 * The hexadecimal values are the intended ones for the following
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 * constants. The decimal values may be used, provided that the
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 * compiler will convert from decimal to binary accurately enough
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 * to produce the hexadecimal values shown.
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 */
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static const double
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ln2_hi  =  6.93147180369123816490e-01,        /* 3fe62e42 fee00000 */
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  ln2_lo  =  1.90821492927058770002e-10,        /* 3dea39ef 35793c76 */
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  Lg1 = 6.666666666666735130e-01,  /* 3FE55555 55555593 */
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  Lg2 = 3.999999999940941908e-01,  /* 3FD99999 9997FA04 */
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  Lg3 = 2.857142874366239149e-01,  /* 3FD24924 94229359 */
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  Lg4 = 2.222219843214978396e-01,  /* 3FCC71C5 1D8E78AF */
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  Lg5 = 1.818357216161805012e-01,  /* 3FC74664 96CB03DE */
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  Lg6 = 1.531383769920937332e-01,  /* 3FC39A09 D078C69F */
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  Lg7 = 1.479819860511658591e-01;  /* 3FC2F112 DF3E5244 */
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static double zero = 0.0;
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static double __ieee754_log(double x) {
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  double hfsq,f,s,z,R,w,t1,t2,dk;
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  int k,hx,i,j;
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  unsigned lx;
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  hx = high(x);               /* high word of x */
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  lx = low(x);                /* low  word of x */
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  k=0;
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  if (hx < 0x00100000) {                   /* x < 2**-1022  */
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    if (((hx&0x7fffffff)|lx)==0)
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      return -two54/zero;             /* log(+-0)=-inf */
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    if (hx<0) return (x-x)/zero;   /* log(-#) = NaN */
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    k -= 54; x *= two54; /* subnormal number, scale up x */
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    hx = high(x);             /* high word of x */
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  }
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  if (hx >= 0x7ff00000) return x+x;
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  k += (hx>>20)-1023;
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  hx &= 0x000fffff;
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  i = (hx+0x95f64)&0x100000;
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  set_high(&x, hx|(i^0x3ff00000)); /* normalize x or x/2 */
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  k += (i>>20);
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  f = x-1.0;
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  if((0x000fffff&(2+hx))<3) {  /* |f| < 2**-20 */
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    if(f==zero) {
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      if (k==0) return zero;
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      else {dk=(double)k; return dk*ln2_hi+dk*ln2_lo;}
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    }
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    R = f*f*(0.5-0.33333333333333333*f);
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    if(k==0) return f-R; else {dk=(double)k;
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    return dk*ln2_hi-((R-dk*ln2_lo)-f);}
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  }
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  s = f/(2.0+f);
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  dk = (double)k;
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  z = s*s;
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  i = hx-0x6147a;
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  w = z*z;
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  j = 0x6b851-hx;
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  t1= w*(Lg2+w*(Lg4+w*Lg6));
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  t2= z*(Lg1+w*(Lg3+w*(Lg5+w*Lg7)));
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  i |= j;
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  R = t2+t1;
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  if(i>0) {
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    hfsq=0.5*f*f;
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    if(k==0) return f-(hfsq-s*(hfsq+R)); else
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      return dk*ln2_hi-((hfsq-(s*(hfsq+R)+dk*ln2_lo))-f);
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  } else {
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    if(k==0) return f-s*(f-R); else
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      return dk*ln2_hi-((s*(f-R)-dk*ln2_lo)-f);
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  }
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}
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JRT_LEAF(jdouble, SharedRuntime::dlog(jdouble x))
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  return __ieee754_log(x);
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JRT_END
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/* __ieee754_log10(x)
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 * Return the base 10 logarithm of x
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 *
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 * Method :
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 *    Let log10_2hi = leading 40 bits of log10(2) and
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 *        log10_2lo = log10(2) - log10_2hi,
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 *        ivln10   = 1/log(10) rounded.
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 *    Then
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 *            n = ilogb(x),
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 *            if(n<0)  n = n+1;
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 *            x = scalbn(x,-n);
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 *            log10(x) := n*log10_2hi + (n*log10_2lo + ivln10*log(x))
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 *
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 * Note 1:
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 *    To guarantee log10(10**n)=n, where 10**n is normal, the rounding
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 *    mode must set to Round-to-Nearest.
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 * Note 2:
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 *    [1/log(10)] rounded to 53 bits has error  .198   ulps;
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 *    log10 is monotonic at all binary break points.
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 *
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 * Special cases:
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 *    log10(x) is NaN with signal if x < 0;
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 *    log10(+INF) is +INF with no signal; log10(0) is -INF with signal;
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 *    log10(NaN) is that NaN with no signal;
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 *    log10(10**N) = N  for N=0,1,...,22.
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 *
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 * Constants:
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 * The hexadecimal values are the intended ones for the following constants.
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 * The decimal values may be used, provided that the compiler will convert
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 * from decimal to binary accurately enough to produce the hexadecimal values
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 * shown.
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 */
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static const double
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ivln10     =  4.34294481903251816668e-01, /* 0x3FDBCB7B, 0x1526E50E */
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  log10_2hi  =  3.01029995663611771306e-01, /* 0x3FD34413, 0x509F6000 */
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  log10_2lo  =  3.69423907715893078616e-13; /* 0x3D59FEF3, 0x11F12B36 */
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static double __ieee754_log10(double x) {
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  double y,z;
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  int i,k,hx;
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  unsigned lx;
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  hx = high(x);       /* high word of x */
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  lx = low(x);        /* low word of x */
1
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  k=0;
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  if (hx < 0x00100000) {                  /* x < 2**-1022  */
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    if (((hx&0x7fffffff)|lx)==0)
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      return -two54/zero;             /* log(+-0)=-inf */
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    if (hx<0) return (x-x)/zero;        /* log(-#) = NaN */
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    k -= 54; x *= two54; /* subnormal number, scale up x */
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    hx = high(x);                /* high word of x */
1
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  }
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  if (hx >= 0x7ff00000) return x+x;
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  k += (hx>>20)-1023;
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  i  = ((unsigned)k&0x80000000)>>31;
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  hx = (hx&0x000fffff)|((0x3ff-i)<<20);
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  y  = (double)(k+i);
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  set_high(&x, hx);
1
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  z  = y*log10_2lo + ivln10*__ieee754_log(x);
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  return  z+y*log10_2hi;
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}
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JRT_LEAF(jdouble, SharedRuntime::dlog10(jdouble x))
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  return __ieee754_log10(x);
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JRT_END
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/* __ieee754_exp(x)
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 * Returns the exponential of x.
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 *
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 * Method
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 *   1. Argument reduction:
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 *      Reduce x to an r so that |r| <= 0.5*ln2 ~ 0.34658.
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 *      Given x, find r and integer k such that
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 *
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 *               x = k*ln2 + r,  |r| <= 0.5*ln2.
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 *
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 *      Here r will be represented as r = hi-lo for better
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 *      accuracy.
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 *
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 *   2. Approximation of exp(r) by a special rational function on
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 *      the interval [0,0.34658]:
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 *      Write
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 *          R(r**2) = r*(exp(r)+1)/(exp(r)-1) = 2 + r*r/6 - r**4/360 + ...
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 *      We use a special Reme algorithm on [0,0.34658] to generate
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 *      a polynomial of degree 5 to approximate R. The maximum error
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 *      of this polynomial approximation is bounded by 2**-59. In
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 *      other words,
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 *          R(z) ~ 2.0 + P1*z + P2*z**2 + P3*z**3 + P4*z**4 + P5*z**5
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 *      (where z=r*r, and the values of P1 to P5 are listed below)
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 *      and
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 *          |                  5          |     -59
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 *          | 2.0+P1*z+...+P5*z   -  R(z) | <= 2
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 *          |                             |
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 *      The computation of exp(r) thus becomes
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 *                             2*r
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 *              exp(r) = 1 + -------
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 *                            R - r
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 *                                 r*R1(r)
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 *                     = 1 + r + ----------- (for better accuracy)
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 *                                2 - R1(r)
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 *      where
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 *                               2       4             10
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 *              R1(r) = r - (P1*r  + P2*r  + ... + P5*r   ).
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 *
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 *   3. Scale back to obtain exp(x):
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 *      From step 1, we have
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 *         exp(x) = 2^k * exp(r)
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 *
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 * Special cases:
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 *      exp(INF) is INF, exp(NaN) is NaN;
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 *      exp(-INF) is 0, and
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 *      for finite argument, only exp(0)=1 is exact.
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 *
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 * Accuracy:
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 *      according to an error analysis, the error is always less than
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 *      1 ulp (unit in the last place).
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 *
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 * Misc. info.
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 *      For IEEE double
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 *          if x >  7.09782712893383973096e+02 then exp(x) overflow
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 *          if x < -7.45133219101941108420e+02 then exp(x) underflow
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 *
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 * Constants:
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 * The hexadecimal values are the intended ones for the following
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 * constants. The decimal values may be used, provided that the
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 * compiler will convert from decimal to binary accurately enough
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 * to produce the hexadecimal values shown.
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 */
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static const double
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one     = 1.0,
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  halF[2]       = {0.5,-0.5,},
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  twom1000= 9.33263618503218878990e-302,     /* 2**-1000=0x01700000,0*/
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    o_threshold=  7.09782712893383973096e+02,  /* 0x40862E42, 0xFEFA39EF */
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    u_threshold= -7.45133219101941108420e+02,  /* 0xc0874910, 0xD52D3051 */
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    ln2HI[2]   ={ 6.93147180369123816490e-01,  /* 0x3fe62e42, 0xfee00000 */
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                  -6.93147180369123816490e-01,},/* 0xbfe62e42, 0xfee00000 */
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    ln2LO[2]   ={ 1.90821492927058770002e-10,  /* 0x3dea39ef, 0x35793c76 */
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                  -1.90821492927058770002e-10,},/* 0xbdea39ef, 0x35793c76 */
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      invln2 =  1.44269504088896338700e+00, /* 0x3ff71547, 0x652b82fe */
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        P1   =  1.66666666666666019037e-01, /* 0x3FC55555, 0x5555553E */
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        P2   = -2.77777777770155933842e-03, /* 0xBF66C16C, 0x16BEBD93 */
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        P3   =  6.61375632143793436117e-05, /* 0x3F11566A, 0xAF25DE2C */
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        P4   = -1.65339022054652515390e-06, /* 0xBEBBBD41, 0xC5D26BF1 */
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        P5   =  4.13813679705723846039e-08; /* 0x3E663769, 0x72BEA4D0 */
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static double __ieee754_exp(double x) {
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  double y,hi=0,lo=0,c,t;
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  int k=0,xsb;
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  unsigned hx;
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  hx  = high(x);                /* high word of x */
1
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  xsb = (hx>>31)&1;             /* sign bit of x */
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  hx &= 0x7fffffff;             /* high word of |x| */
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  /* filter out non-finite argument */
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  if(hx >= 0x40862E42) {                        /* if |x|>=709.78... */
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    if(hx>=0x7ff00000) {
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      if(((hx&0xfffff)|low(x))!=0)
1
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        return x+x;             /* NaN */
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      else return (xsb==0)? x:0.0;      /* exp(+-inf)={inf,0} */
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    }
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    if(x > o_threshold) return hugeX*hugeX; /* overflow */
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    if(x < u_threshold) return twom1000*twom1000; /* underflow */
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  }
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  /* argument reduction */
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  if(hx > 0x3fd62e42) {         /* if  |x| > 0.5 ln2 */
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    if(hx < 0x3FF0A2B2) {       /* and |x| < 1.5 ln2 */
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      hi = x-ln2HI[xsb]; lo=ln2LO[xsb]; k = 1-xsb-xsb;
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    } else {
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      k  = (int)(invln2*x+halF[xsb]);
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      t  = k;
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      hi = x - t*ln2HI[0];      /* t*ln2HI is exact here */
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      lo = t*ln2LO[0];
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    }
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    x  = hi - lo;
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  }
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  else if(hx < 0x3e300000)  {   /* when |x|<2**-28 */
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    if(hugeX+x>one) return one+x;/* trigger inexact */
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  }
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  else k = 0;
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parents:
diff changeset
   354
489c9b5090e2 Initial load
duke
parents:
diff changeset
   355
  /* x is now in primary range */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   356
  t  = x*x;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   357
  c  = x - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))));
489c9b5090e2 Initial load
duke
parents:
diff changeset
   358
  if(k==0)      return one-((x*c)/(c-2.0)-x);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   359
  else          y = one-((lo-(x*c)/(2.0-c))-hi);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   360
  if(k >= -1021) {
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   361
    set_high(&y, high(y) + (k<<20)); /* add k to y's exponent */
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   362
    return y;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   363
  } else {
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   364
    set_high(&y, high(y) + ((k+1000)<<20)); /* add k to y's exponent */
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   365
    return y*twom1000;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   366
  }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   367
}
489c9b5090e2 Initial load
duke
parents:
diff changeset
   368
489c9b5090e2 Initial load
duke
parents:
diff changeset
   369
JRT_LEAF(jdouble, SharedRuntime::dexp(jdouble x))
489c9b5090e2 Initial load
duke
parents:
diff changeset
   370
  return __ieee754_exp(x);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   371
JRT_END
489c9b5090e2 Initial load
duke
parents:
diff changeset
   372
489c9b5090e2 Initial load
duke
parents:
diff changeset
   373
/* __ieee754_pow(x,y) return x**y
489c9b5090e2 Initial load
duke
parents:
diff changeset
   374
 *
489c9b5090e2 Initial load
duke
parents:
diff changeset
   375
 *                    n
489c9b5090e2 Initial load
duke
parents:
diff changeset
   376
 * Method:  Let x =  2   * (1+f)
489c9b5090e2 Initial load
duke
parents:
diff changeset
   377
 *      1. Compute and return log2(x) in two pieces:
489c9b5090e2 Initial load
duke
parents:
diff changeset
   378
 *              log2(x) = w1 + w2,
489c9b5090e2 Initial load
duke
parents:
diff changeset
   379
 *         where w1 has 53-24 = 29 bit trailing zeros.
489c9b5090e2 Initial load
duke
parents:
diff changeset
   380
 *      2. Perform y*log2(x) = n+y' by simulating muti-precision
489c9b5090e2 Initial load
duke
parents:
diff changeset
   381
 *         arithmetic, where |y'|<=0.5.
489c9b5090e2 Initial load
duke
parents:
diff changeset
   382
 *      3. Return x**y = 2**n*exp(y'*log2)
489c9b5090e2 Initial load
duke
parents:
diff changeset
   383
 *
489c9b5090e2 Initial load
duke
parents:
diff changeset
   384
 * Special cases:
489c9b5090e2 Initial load
duke
parents:
diff changeset
   385
 *      1.  (anything) ** 0  is 1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   386
 *      2.  (anything) ** 1  is itself
489c9b5090e2 Initial load
duke
parents:
diff changeset
   387
 *      3.  (anything) ** NAN is NAN
489c9b5090e2 Initial load
duke
parents:
diff changeset
   388
 *      4.  NAN ** (anything except 0) is NAN
489c9b5090e2 Initial load
duke
parents:
diff changeset
   389
 *      5.  +-(|x| > 1) **  +INF is +INF
489c9b5090e2 Initial load
duke
parents:
diff changeset
   390
 *      6.  +-(|x| > 1) **  -INF is +0
489c9b5090e2 Initial load
duke
parents:
diff changeset
   391
 *      7.  +-(|x| < 1) **  +INF is +0
489c9b5090e2 Initial load
duke
parents:
diff changeset
   392
 *      8.  +-(|x| < 1) **  -INF is +INF
489c9b5090e2 Initial load
duke
parents:
diff changeset
   393
 *      9.  +-1         ** +-INF is NAN
489c9b5090e2 Initial load
duke
parents:
diff changeset
   394
 *      10. +0 ** (+anything except 0, NAN)               is +0
489c9b5090e2 Initial load
duke
parents:
diff changeset
   395
 *      11. -0 ** (+anything except 0, NAN, odd integer)  is +0
489c9b5090e2 Initial load
duke
parents:
diff changeset
   396
 *      12. +0 ** (-anything except 0, NAN)               is +INF
489c9b5090e2 Initial load
duke
parents:
diff changeset
   397
 *      13. -0 ** (-anything except 0, NAN, odd integer)  is +INF
489c9b5090e2 Initial load
duke
parents:
diff changeset
   398
 *      14. -0 ** (odd integer) = -( +0 ** (odd integer) )
489c9b5090e2 Initial load
duke
parents:
diff changeset
   399
 *      15. +INF ** (+anything except 0,NAN) is +INF
489c9b5090e2 Initial load
duke
parents:
diff changeset
   400
 *      16. +INF ** (-anything except 0,NAN) is +0
489c9b5090e2 Initial load
duke
parents:
diff changeset
   401
 *      17. -INF ** (anything)  = -0 ** (-anything)
489c9b5090e2 Initial load
duke
parents:
diff changeset
   402
 *      18. (-anything) ** (integer) is (-1)**(integer)*(+anything**integer)
489c9b5090e2 Initial load
duke
parents:
diff changeset
   403
 *      19. (-anything except 0 and inf) ** (non-integer) is NAN
489c9b5090e2 Initial load
duke
parents:
diff changeset
   404
 *
489c9b5090e2 Initial load
duke
parents:
diff changeset
   405
 * Accuracy:
489c9b5090e2 Initial load
duke
parents:
diff changeset
   406
 *      pow(x,y) returns x**y nearly rounded. In particular
489c9b5090e2 Initial load
duke
parents:
diff changeset
   407
 *                      pow(integer,integer)
489c9b5090e2 Initial load
duke
parents:
diff changeset
   408
 *      always returns the correct integer provided it is
489c9b5090e2 Initial load
duke
parents:
diff changeset
   409
 *      representable.
489c9b5090e2 Initial load
duke
parents:
diff changeset
   410
 *
489c9b5090e2 Initial load
duke
parents:
diff changeset
   411
 * Constants :
489c9b5090e2 Initial load
duke
parents:
diff changeset
   412
 * The hexadecimal values are the intended ones for the following
489c9b5090e2 Initial load
duke
parents:
diff changeset
   413
 * constants. The decimal values may be used, provided that the
489c9b5090e2 Initial load
duke
parents:
diff changeset
   414
 * compiler will convert from decimal to binary accurately enough
489c9b5090e2 Initial load
duke
parents:
diff changeset
   415
 * to produce the hexadecimal values shown.
489c9b5090e2 Initial load
duke
parents:
diff changeset
   416
 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   417
489c9b5090e2 Initial load
duke
parents:
diff changeset
   418
static const double
489c9b5090e2 Initial load
duke
parents:
diff changeset
   419
bp[] = {1.0, 1.5,},
489c9b5090e2 Initial load
duke
parents:
diff changeset
   420
  dp_h[] = { 0.0, 5.84962487220764160156e-01,}, /* 0x3FE2B803, 0x40000000 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   421
    dp_l[] = { 0.0, 1.35003920212974897128e-08,}, /* 0x3E4CFDEB, 0x43CFD006 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   422
      zeroX    =  0.0,
489c9b5090e2 Initial load
duke
parents:
diff changeset
   423
        two     =  2.0,
489c9b5090e2 Initial load
duke
parents:
diff changeset
   424
        two53   =  9007199254740992.0,  /* 0x43400000, 0x00000000 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   425
        /* poly coefs for (3/2)*(log(x)-2s-2/3*s**3 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   426
        L1X  =  5.99999999999994648725e-01, /* 0x3FE33333, 0x33333303 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   427
        L2X  =  4.28571428578550184252e-01, /* 0x3FDB6DB6, 0xDB6FABFF */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   428
        L3X  =  3.33333329818377432918e-01, /* 0x3FD55555, 0x518F264D */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   429
        L4X  =  2.72728123808534006489e-01, /* 0x3FD17460, 0xA91D4101 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   430
        L5X  =  2.30660745775561754067e-01, /* 0x3FCD864A, 0x93C9DB65 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   431
        L6X  =  2.06975017800338417784e-01, /* 0x3FCA7E28, 0x4A454EEF */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   432
        lg2  =  6.93147180559945286227e-01, /* 0x3FE62E42, 0xFEFA39EF */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   433
        lg2_h  =  6.93147182464599609375e-01, /* 0x3FE62E43, 0x00000000 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   434
        lg2_l  = -1.90465429995776804525e-09, /* 0xBE205C61, 0x0CA86C39 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   435
        ovt =  8.0085662595372944372e-0017, /* -(1024-log2(ovfl+.5ulp)) */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   436
        cp    =  9.61796693925975554329e-01, /* 0x3FEEC709, 0xDC3A03FD =2/(3ln2) */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   437
        cp_h  =  9.61796700954437255859e-01, /* 0x3FEEC709, 0xE0000000 =(float)cp */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   438
        cp_l  = -7.02846165095275826516e-09, /* 0xBE3E2FE0, 0x145B01F5 =tail of cp_h*/
489c9b5090e2 Initial load
duke
parents:
diff changeset
   439
        ivln2    =  1.44269504088896338700e+00, /* 0x3FF71547, 0x652B82FE =1/ln2 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   440
        ivln2_h  =  1.44269502162933349609e+00, /* 0x3FF71547, 0x60000000 =24b 1/ln2*/
489c9b5090e2 Initial load
duke
parents:
diff changeset
   441
        ivln2_l  =  1.92596299112661746887e-08; /* 0x3E54AE0B, 0xF85DDF44 =1/ln2 tail*/
489c9b5090e2 Initial load
duke
parents:
diff changeset
   442
489c9b5090e2 Initial load
duke
parents:
diff changeset
   443
double __ieee754_pow(double x, double y) {
489c9b5090e2 Initial load
duke
parents:
diff changeset
   444
  double z,ax,z_h,z_l,p_h,p_l;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   445
  double y1,t1,t2,r,s,t,u,v,w;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   446
  int i0,i1,i,j,k,yisint,n;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   447
  int hx,hy,ix,iy;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   448
  unsigned lx,ly;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   449
489c9b5090e2 Initial load
duke
parents:
diff changeset
   450
  i0 = ((*(int*)&one)>>29)^1; i1=1-i0;
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   451
  hx = high(x); lx = low(x);
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   452
  hy = high(y); ly = low(y);
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   453
  ix = hx&0x7fffffff;  iy = hy&0x7fffffff;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   454
489c9b5090e2 Initial load
duke
parents:
diff changeset
   455
  /* y==zero: x**0 = 1 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   456
  if((iy|ly)==0) return one;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   457
489c9b5090e2 Initial load
duke
parents:
diff changeset
   458
  /* +-NaN return x+y */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   459
  if(ix > 0x7ff00000 || ((ix==0x7ff00000)&&(lx!=0)) ||
489c9b5090e2 Initial load
duke
parents:
diff changeset
   460
     iy > 0x7ff00000 || ((iy==0x7ff00000)&&(ly!=0)))
489c9b5090e2 Initial load
duke
parents:
diff changeset
   461
    return x+y;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   462
489c9b5090e2 Initial load
duke
parents:
diff changeset
   463
  /* determine if y is an odd int when x < 0
489c9b5090e2 Initial load
duke
parents:
diff changeset
   464
   * yisint = 0 ... y is not an integer
489c9b5090e2 Initial load
duke
parents:
diff changeset
   465
   * yisint = 1 ... y is an odd int
489c9b5090e2 Initial load
duke
parents:
diff changeset
   466
   * yisint = 2 ... y is an even int
489c9b5090e2 Initial load
duke
parents:
diff changeset
   467
   */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   468
  yisint  = 0;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   469
  if(hx<0) {
489c9b5090e2 Initial load
duke
parents:
diff changeset
   470
    if(iy>=0x43400000) yisint = 2; /* even integer y */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   471
    else if(iy>=0x3ff00000) {
489c9b5090e2 Initial load
duke
parents:
diff changeset
   472
      k = (iy>>20)-0x3ff;          /* exponent */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   473
      if(k>20) {
489c9b5090e2 Initial load
duke
parents:
diff changeset
   474
        j = ly>>(52-k);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   475
        if((unsigned)(j<<(52-k))==ly) yisint = 2-(j&1);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   476
      } else if(ly==0) {
489c9b5090e2 Initial load
duke
parents:
diff changeset
   477
        j = iy>>(20-k);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   478
        if((j<<(20-k))==iy) yisint = 2-(j&1);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   479
      }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   480
    }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   481
  }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   482
489c9b5090e2 Initial load
duke
parents:
diff changeset
   483
  /* special value of y */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   484
  if(ly==0) {
489c9b5090e2 Initial load
duke
parents:
diff changeset
   485
    if (iy==0x7ff00000) {       /* y is +-inf */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   486
      if(((ix-0x3ff00000)|lx)==0)
489c9b5090e2 Initial load
duke
parents:
diff changeset
   487
        return  y - y;  /* inf**+-1 is NaN */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   488
      else if (ix >= 0x3ff00000)/* (|x|>1)**+-inf = inf,0 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   489
        return (hy>=0)? y: zeroX;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   490
      else                      /* (|x|<1)**-,+inf = inf,0 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   491
        return (hy<0)?-y: zeroX;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   492
    }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   493
    if(iy==0x3ff00000) {        /* y is  +-1 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   494
      if(hy<0) return one/x; else return x;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   495
    }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   496
    if(hy==0x40000000) return x*x; /* y is  2 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   497
    if(hy==0x3fe00000) {        /* y is  0.5 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   498
      if(hx>=0) /* x >= +0 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   499
        return sqrt(x);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   500
    }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   501
  }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   502
489c9b5090e2 Initial load
duke
parents:
diff changeset
   503
  ax   = fabsd(x);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   504
  /* special value of x */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   505
  if(lx==0) {
489c9b5090e2 Initial load
duke
parents:
diff changeset
   506
    if(ix==0x7ff00000||ix==0||ix==0x3ff00000){
489c9b5090e2 Initial load
duke
parents:
diff changeset
   507
      z = ax;                   /*x is +-0,+-inf,+-1*/
489c9b5090e2 Initial load
duke
parents:
diff changeset
   508
      if(hy<0) z = one/z;       /* z = (1/|x|) */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   509
      if(hx<0) {
489c9b5090e2 Initial load
duke
parents:
diff changeset
   510
        if(((ix-0x3ff00000)|yisint)==0) {
6176
4d9030fe341f 6953477: Increase portability and flexibility of building Hotspot
bobv
parents: 5547
diff changeset
   511
#ifdef CAN_USE_NAN_DEFINE
4d9030fe341f 6953477: Increase portability and flexibility of building Hotspot
bobv
parents: 5547
diff changeset
   512
          z = NAN;
4d9030fe341f 6953477: Increase portability and flexibility of building Hotspot
bobv
parents: 5547
diff changeset
   513
#else
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   514
          z = (z-z)/(z-z); /* (-1)**non-int is NaN */
6176
4d9030fe341f 6953477: Increase portability and flexibility of building Hotspot
bobv
parents: 5547
diff changeset
   515
#endif
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   516
        } else if(yisint==1)
489c9b5090e2 Initial load
duke
parents:
diff changeset
   517
          z = -1.0*z;           /* (x<0)**odd = -(|x|**odd) */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   518
      }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   519
      return z;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   520
    }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   521
  }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   522
489c9b5090e2 Initial load
duke
parents:
diff changeset
   523
  n = (hx>>31)+1;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   524
489c9b5090e2 Initial load
duke
parents:
diff changeset
   525
  /* (x<0)**(non-int) is NaN */
6176
4d9030fe341f 6953477: Increase portability and flexibility of building Hotspot
bobv
parents: 5547
diff changeset
   526
  if((n|yisint)==0)
4d9030fe341f 6953477: Increase portability and flexibility of building Hotspot
bobv
parents: 5547
diff changeset
   527
#ifdef CAN_USE_NAN_DEFINE
4d9030fe341f 6953477: Increase portability and flexibility of building Hotspot
bobv
parents: 5547
diff changeset
   528
    return NAN;
4d9030fe341f 6953477: Increase portability and flexibility of building Hotspot
bobv
parents: 5547
diff changeset
   529
#else
4d9030fe341f 6953477: Increase portability and flexibility of building Hotspot
bobv
parents: 5547
diff changeset
   530
    return (x-x)/(x-x);
4d9030fe341f 6953477: Increase portability and flexibility of building Hotspot
bobv
parents: 5547
diff changeset
   531
#endif
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   532
489c9b5090e2 Initial load
duke
parents:
diff changeset
   533
  s = one; /* s (sign of result -ve**odd) = -1 else = 1 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   534
  if((n|(yisint-1))==0) s = -one;/* (-ve)**(odd int) */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   535
489c9b5090e2 Initial load
duke
parents:
diff changeset
   536
  /* |y| is huge */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   537
  if(iy>0x41e00000) { /* if |y| > 2**31 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   538
    if(iy>0x43f00000){  /* if |y| > 2**64, must o/uflow */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   539
      if(ix<=0x3fefffff) return (hy<0)? hugeX*hugeX:tiny*tiny;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   540
      if(ix>=0x3ff00000) return (hy>0)? hugeX*hugeX:tiny*tiny;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   541
    }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   542
    /* over/underflow if x is not close to one */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   543
    if(ix<0x3fefffff) return (hy<0)? s*hugeX*hugeX:s*tiny*tiny;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   544
    if(ix>0x3ff00000) return (hy>0)? s*hugeX*hugeX:s*tiny*tiny;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   545
    /* now |1-x| is tiny <= 2**-20, suffice to compute
489c9b5090e2 Initial load
duke
parents:
diff changeset
   546
       log(x) by x-x^2/2+x^3/3-x^4/4 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   547
    t = ax-one;         /* t has 20 trailing zeros */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   548
    w = (t*t)*(0.5-t*(0.3333333333333333333333-t*0.25));
489c9b5090e2 Initial load
duke
parents:
diff changeset
   549
    u = ivln2_h*t;      /* ivln2_h has 21 sig. bits */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   550
    v = t*ivln2_l-w*ivln2;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   551
    t1 = u+v;
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   552
    set_low(&t1, 0);
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   553
    t2 = v-(t1-u);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   554
  } else {
489c9b5090e2 Initial load
duke
parents:
diff changeset
   555
    double ss,s2,s_h,s_l,t_h,t_l;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   556
    n = 0;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   557
    /* take care subnormal number */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   558
    if(ix<0x00100000)
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   559
      {ax *= two53; n -= 53; ix = high(ax); }
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   560
    n  += ((ix)>>20)-0x3ff;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   561
    j  = ix&0x000fffff;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   562
    /* determine interval */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   563
    ix = j|0x3ff00000;          /* normalize ix */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   564
    if(j<=0x3988E) k=0;         /* |x|<sqrt(3/2) */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   565
    else if(j<0xBB67A) k=1;     /* |x|<sqrt(3)   */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   566
    else {k=0;n+=1;ix -= 0x00100000;}
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   567
    set_high(&ax, ix);
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   568
489c9b5090e2 Initial load
duke
parents:
diff changeset
   569
    /* compute ss = s_h+s_l = (x-1)/(x+1) or (x-1.5)/(x+1.5) */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   570
    u = ax-bp[k];               /* bp[0]=1.0, bp[1]=1.5 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   571
    v = one/(ax+bp[k]);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   572
    ss = u*v;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   573
    s_h = ss;
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   574
    set_low(&s_h, 0);
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   575
    /* t_h=ax+bp[k] High */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   576
    t_h = zeroX;
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   577
    set_high(&t_h, ((ix>>1)|0x20000000)+0x00080000+(k<<18));
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   578
    t_l = ax - (t_h-bp[k]);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   579
    s_l = v*((u-s_h*t_h)-s_h*t_l);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   580
    /* compute log(ax) */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   581
    s2 = ss*ss;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   582
    r = s2*s2*(L1X+s2*(L2X+s2*(L3X+s2*(L4X+s2*(L5X+s2*L6X)))));
489c9b5090e2 Initial load
duke
parents:
diff changeset
   583
    r += s_l*(s_h+ss);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   584
    s2  = s_h*s_h;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   585
    t_h = 3.0+s2+r;
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   586
    set_low(&t_h, 0);
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   587
    t_l = r-((t_h-3.0)-s2);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   588
    /* u+v = ss*(1+...) */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   589
    u = s_h*t_h;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   590
    v = s_l*t_h+t_l*ss;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   591
    /* 2/(3log2)*(ss+...) */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   592
    p_h = u+v;
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   593
    set_low(&p_h, 0);
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   594
    p_l = v-(p_h-u);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   595
    z_h = cp_h*p_h;             /* cp_h+cp_l = 2/(3*log2) */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   596
    z_l = cp_l*p_h+p_l*cp+dp_l[k];
489c9b5090e2 Initial load
duke
parents:
diff changeset
   597
    /* log2(ax) = (ss+..)*2/(3*log2) = n + dp_h + z_h + z_l */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   598
    t = (double)n;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   599
    t1 = (((z_h+z_l)+dp_h[k])+t);
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   600
    set_low(&t1, 0);
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   601
    t2 = z_l-(((t1-t)-dp_h[k])-z_h);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   602
  }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   603
489c9b5090e2 Initial load
duke
parents:
diff changeset
   604
  /* split up y into y1+y2 and compute (y1+y2)*(t1+t2) */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   605
  y1  = y;
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   606
  set_low(&y1, 0);
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   607
  p_l = (y-y1)*t1+y*t2;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   608
  p_h = y1*t1;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   609
  z = p_l+p_h;
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   610
  j = high(z);
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   611
  i = low(z);
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   612
  if (j>=0x40900000) {                          /* z >= 1024 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   613
    if(((j-0x40900000)|i)!=0)                   /* if z > 1024 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   614
      return s*hugeX*hugeX;                     /* overflow */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   615
    else {
489c9b5090e2 Initial load
duke
parents:
diff changeset
   616
      if(p_l+ovt>z-p_h) return s*hugeX*hugeX;   /* overflow */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   617
    }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   618
  } else if((j&0x7fffffff)>=0x4090cc00 ) {      /* z <= -1075 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   619
    if(((j-0xc090cc00)|i)!=0)           /* z < -1075 */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   620
      return s*tiny*tiny;               /* underflow */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   621
    else {
489c9b5090e2 Initial load
duke
parents:
diff changeset
   622
      if(p_l<=z-p_h) return s*tiny*tiny;        /* underflow */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   623
    }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   624
  }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   625
  /*
489c9b5090e2 Initial load
duke
parents:
diff changeset
   626
   * compute 2**(p_h+p_l)
489c9b5090e2 Initial load
duke
parents:
diff changeset
   627
   */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   628
  i = j&0x7fffffff;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   629
  k = (i>>20)-0x3ff;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   630
  n = 0;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   631
  if(i>0x3fe00000) {            /* if |z| > 0.5, set n = [z+0.5] */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   632
    n = j+(0x00100000>>(k+1));
489c9b5090e2 Initial load
duke
parents:
diff changeset
   633
    k = ((n&0x7fffffff)>>20)-0x3ff;     /* new k for n */
489c9b5090e2 Initial load
duke
parents:
diff changeset
   634
    t = zeroX;
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   635
    set_high(&t, (n&~(0x000fffff>>k)));
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   636
    n = ((n&0x000fffff)|0x00100000)>>(20-k);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   637
    if(j<0) n = -n;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   638
    p_h -= t;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   639
  }
489c9b5090e2 Initial load
duke
parents:
diff changeset
   640
  t = p_l+p_h;
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   641
  set_low(&t, 0);
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   642
  u = t*lg2_h;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   643
  v = (p_l-(t-p_h))*lg2+t*lg2_l;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   644
  z = u+v;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   645
  w = v-(z-u);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   646
  t  = z*z;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   647
  t1  = z - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))));
489c9b5090e2 Initial load
duke
parents:
diff changeset
   648
  r  = (z*t1)/(t1-two)-(w+z*w);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   649
  z  = one-(r-z);
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   650
  j  = high(z);
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   651
  j += (n<<20);
24660
a9b2a80f5afa 8043301: Duplicate definitions in vm/runtime/sharedRuntimeTrans.cpp versus math.h in VS2013
lfoltan
parents: 22876
diff changeset
   652
  if((j>>20)<=0) z = scalbnA(z,n);       /* subnormal output */
25919
d4e4f72b49fc 8049043: Load variable through a pointer of an incompatible type in hotspot/src/share/vm/runtime/sharedRuntimeMath.hpp
thartmann
parents: 24660
diff changeset
   653
  else set_high(&z, high(z) + (n<<20));
1
489c9b5090e2 Initial load
duke
parents:
diff changeset
   654
  return s*z;
489c9b5090e2 Initial load
duke
parents:
diff changeset
   655
}
489c9b5090e2 Initial load
duke
parents:
diff changeset
   656
489c9b5090e2 Initial load
duke
parents:
diff changeset
   657
489c9b5090e2 Initial load
duke
parents:
diff changeset
   658
JRT_LEAF(jdouble, SharedRuntime::dpow(jdouble x, jdouble y))
489c9b5090e2 Initial load
duke
parents:
diff changeset
   659
  return __ieee754_pow(x, y);
489c9b5090e2 Initial load
duke
parents:
diff changeset
   660
JRT_END
489c9b5090e2 Initial load
duke
parents:
diff changeset
   661
489c9b5090e2 Initial load
duke
parents:
diff changeset
   662
#ifdef WIN32
489c9b5090e2 Initial load
duke
parents:
diff changeset
   663
# pragma optimize ( "", on )
489c9b5090e2 Initial load
duke
parents:
diff changeset
   664
#endif