annotate src/share/vm/runtime/sharedRuntimeTrig.cpp @ 1721:413ad0331a0c

6977924: Changes for 6975078 produce build error with certain gcc versions Summary: The changes introduced for 6975078 assign badHeapOopVal to the _allocation field in the ResourceObj class. In 32 bit linux builds with certain versions of gcc this assignment will be flagged as an error while compiling allocation.cpp. In 32 bit builds the constant value badHeapOopVal (which is cast to an intptr_t) is negative. The _allocation field is typed as an unsigned intptr_t and gcc catches this as an error. Reviewed-by: jcoomes, ysr, phh
author johnc
date Wed, 18 Aug 2010 10:59:06 -0700
parents c18cbe5936b8
children f95d63e2154a
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1 /*
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2 * Copyright (c) 2001, 2005, Oracle and/or its affiliates. All rights reserved.
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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4 *
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5 * This code is free software; you can redistribute it and/or modify it
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6 * under the terms of the GNU General Public License version 2 only, as
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7 * published by the Free Software Foundation.
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8 *
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9 * This code is distributed in the hope that it will be useful, but WITHOUT
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10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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12 * version 2 for more details (a copy is included in the LICENSE file that
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13 * accompanied this code).
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14 *
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15 * You should have received a copy of the GNU General Public License version
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16 * 2 along with this work; if not, write to the Free Software Foundation,
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17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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18 *
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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20 * or visit www.oracle.com if you need additional information or have any
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21 * questions.
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22 *
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23 */
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24
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25 #include "incls/_precompiled.incl"
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26 #include "incls/_sharedRuntimeTrig.cpp.incl"
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27
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28 // This file contains copies of the fdlibm routines used by
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29 // StrictMath. It turns out that it is almost always required to use
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30 // these runtime routines; the Intel CPU doesn't meet the Java
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31 // specification for sin/cos outside a certain limited argument range,
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32 // and the SPARC CPU doesn't appear to have sin/cos instructions. It
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33 // also turns out that avoiding the indirect call through function
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34 // pointer out to libjava.so in SharedRuntime speeds these routines up
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35 // by roughly 15% on both Win32/x86 and Solaris/SPARC.
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36
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37 // Enabling optimizations in this file causes incorrect code to be
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38 // generated; can not figure out how to turn down optimization for one
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39 // file in the IDE on Windows
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40 #ifdef WIN32
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41 # pragma optimize ( "", off )
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42 #endif
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43
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44 /* The above workaround now causes more problems with the latest MS compiler.
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45 * Visual Studio 2010's /GS option tries to guard against buffer overruns.
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46 * /GS is on by default if you specify optimizations, which we do globally
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47 * via /W3 /O2. However the above selective turning off of optimizations means
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48 * that /GS issues a warning "4748". And since we treat warnings as errors (/WX)
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49 * then the compilation fails. There are several possible solutions
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50 * (1) Remove that pragma above as obsolete with VS2010 - requires testing.
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51 * (2) Stop treating warnings as errors - would be a backward step
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52 * (3) Disable /GS - may help performance but you lose the security checks
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53 * (4) Disable the warning with "#pragma warning( disable : 4748 )"
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54 * (5) Disable planting the code with __declspec(safebuffers)
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55 * I've opted for (5) although we should investigate the local performance
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56 * benefits of (1) and global performance benefit of (3).
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57 */
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58 #if defined(WIN32) && (defined(_MSC_VER) && (_MSC_VER >= 1600))
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59 #define SAFEBUF __declspec(safebuffers)
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60 #else
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61 #define SAFEBUF
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62 #endif
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63
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64 #include <math.h>
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65
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66 // VM_LITTLE_ENDIAN is #defined appropriately in the Makefiles
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67 // [jk] this is not 100% correct because the float word order may different
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68 // from the byte order (e.g. on ARM)
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69 #ifdef VM_LITTLE_ENDIAN
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70 # define __HI(x) *(1+(int*)&x)
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71 # define __LO(x) *(int*)&x
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72 #else
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73 # define __HI(x) *(int*)&x
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74 # define __LO(x) *(1+(int*)&x)
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75 #endif
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76
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77 static double copysignA(double x, double y) {
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78 __HI(x) = (__HI(x)&0x7fffffff)|(__HI(y)&0x80000000);
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79 return x;
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80 }
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81
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82 /*
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83 * scalbn (double x, int n)
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84 * scalbn(x,n) returns x* 2**n computed by exponent
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85 * manipulation rather than by actually performing an
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86 * exponentiation or a multiplication.
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87 */
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88
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89 static const double
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90 two54 = 1.80143985094819840000e+16, /* 0x43500000, 0x00000000 */
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91 twom54 = 5.55111512312578270212e-17, /* 0x3C900000, 0x00000000 */
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92 hugeX = 1.0e+300,
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93 tiny = 1.0e-300;
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94
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95 static double scalbnA (double x, int n) {
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96 int k,hx,lx;
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97 hx = __HI(x);
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98 lx = __LO(x);
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99 k = (hx&0x7ff00000)>>20; /* extract exponent */
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100 if (k==0) { /* 0 or subnormal x */
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101 if ((lx|(hx&0x7fffffff))==0) return x; /* +-0 */
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102 x *= two54;
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103 hx = __HI(x);
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104 k = ((hx&0x7ff00000)>>20) - 54;
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105 if (n< -50000) return tiny*x; /*underflow*/
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106 }
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107 if (k==0x7ff) return x+x; /* NaN or Inf */
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108 k = k+n;
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109 if (k > 0x7fe) return hugeX*copysignA(hugeX,x); /* overflow */
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110 if (k > 0) /* normal result */
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111 {__HI(x) = (hx&0x800fffff)|(k<<20); return x;}
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112 if (k <= -54) {
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113 if (n > 50000) /* in case integer overflow in n+k */
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114 return hugeX*copysignA(hugeX,x); /*overflow*/
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115 else return tiny*copysignA(tiny,x); /*underflow*/
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116 }
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117 k += 54; /* subnormal result */
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118 __HI(x) = (hx&0x800fffff)|(k<<20);
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119 return x*twom54;
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120 }
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121
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122 /*
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123 * __kernel_rem_pio2(x,y,e0,nx,prec,ipio2)
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124 * double x[],y[]; int e0,nx,prec; int ipio2[];
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125 *
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126 * __kernel_rem_pio2 return the last three digits of N with
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127 * y = x - N*pi/2
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128 * so that |y| < pi/2.
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129 *
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130 * The method is to compute the integer (mod 8) and fraction parts of
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131 * (2/pi)*x without doing the full multiplication. In general we
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132 * skip the part of the product that are known to be a huge integer (
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133 * more accurately, = 0 mod 8 ). Thus the number of operations are
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134 * independent of the exponent of the input.
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135 *
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136 * (2/pi) is represented by an array of 24-bit integers in ipio2[].
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137 *
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138 * Input parameters:
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139 * x[] The input value (must be positive) is broken into nx
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140 * pieces of 24-bit integers in double precision format.
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141 * x[i] will be the i-th 24 bit of x. The scaled exponent
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142 * of x[0] is given in input parameter e0 (i.e., x[0]*2^e0
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143 * match x's up to 24 bits.
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144 *
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145 * Example of breaking a double positive z into x[0]+x[1]+x[2]:
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146 * e0 = ilogb(z)-23
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147 * z = scalbn(z,-e0)
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148 * for i = 0,1,2
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149 * x[i] = floor(z)
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150 * z = (z-x[i])*2**24
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151 *
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152 *
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153 * y[] ouput result in an array of double precision numbers.
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154 * The dimension of y[] is:
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155 * 24-bit precision 1
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156 * 53-bit precision 2
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157 * 64-bit precision 2
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158 * 113-bit precision 3
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159 * The actual value is the sum of them. Thus for 113-bit
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160 * precsion, one may have to do something like:
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161 *
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162 * long double t,w,r_head, r_tail;
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163 * t = (long double)y[2] + (long double)y[1];
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164 * w = (long double)y[0];
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165 * r_head = t+w;
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166 * r_tail = w - (r_head - t);
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167 *
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168 * e0 The exponent of x[0]
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169 *
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170 * nx dimension of x[]
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171 *
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172 * prec an interger indicating the precision:
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173 * 0 24 bits (single)
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174 * 1 53 bits (double)
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175 * 2 64 bits (extended)
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176 * 3 113 bits (quad)
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177 *
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178 * ipio2[]
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179 * integer array, contains the (24*i)-th to (24*i+23)-th
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180 * bit of 2/pi after binary point. The corresponding
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181 * floating value is
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182 *
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183 * ipio2[i] * 2^(-24(i+1)).
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184 *
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185 * External function:
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186 * double scalbn(), floor();
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187 *
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188 *
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189 * Here is the description of some local variables:
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190 *
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191 * jk jk+1 is the initial number of terms of ipio2[] needed
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192 * in the computation. The recommended value is 2,3,4,
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193 * 6 for single, double, extended,and quad.
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194 *
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195 * jz local integer variable indicating the number of
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196 * terms of ipio2[] used.
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197 *
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198 * jx nx - 1
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199 *
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200 * jv index for pointing to the suitable ipio2[] for the
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201 * computation. In general, we want
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202 * ( 2^e0*x[0] * ipio2[jv-1]*2^(-24jv) )/8
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203 * is an integer. Thus
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204 * e0-3-24*jv >= 0 or (e0-3)/24 >= jv
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205 * Hence jv = max(0,(e0-3)/24).
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206 *
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207 * jp jp+1 is the number of terms in PIo2[] needed, jp = jk.
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208 *
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209 * q[] double array with integral value, representing the
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210 * 24-bits chunk of the product of x and 2/pi.
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211 *
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212 * q0 the corresponding exponent of q[0]. Note that the
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213 * exponent for q[i] would be q0-24*i.
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214 *
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215 * PIo2[] double precision array, obtained by cutting pi/2
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216 * into 24 bits chunks.
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diff changeset
217 *
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218 * f[] ipio2[] in floating point
a61af66fc99e Initial load
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parents:
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219 *
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220 * iq[] integer array by breaking up q[] in 24-bits chunk.
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parents:
diff changeset
221 *
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parents:
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222 * fq[] final product of x*(2/pi) in fq[0],..,fq[jk]
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parents:
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223 *
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224 * ih integer. If >0 it indicats q[] is >= 0.5, hence
a61af66fc99e Initial load
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parents:
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225 * it also indicates the *sign* of the result.
a61af66fc99e Initial load
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parents:
diff changeset
226 *
a61af66fc99e Initial load
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parents:
diff changeset
227 */
a61af66fc99e Initial load
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parents:
diff changeset
228
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diff changeset
229
a61af66fc99e Initial load
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parents:
diff changeset
230 /*
a61af66fc99e Initial load
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parents:
diff changeset
231 * Constants:
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parents:
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232 * The hexadecimal values are the intended ones for the following
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233 * constants. The decimal values may be used, provided that the
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234 * compiler will convert from decimal to binary accurately enough
a61af66fc99e Initial load
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235 * to produce the hexadecimal values shown.
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parents:
diff changeset
236 */
a61af66fc99e Initial load
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diff changeset
237
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238
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239 static const int init_jk[] = {2,3,4,6}; /* initial value for jk */
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240
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241 static const double PIo2[] = {
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242 1.57079625129699707031e+00, /* 0x3FF921FB, 0x40000000 */
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diff changeset
243 7.54978941586159635335e-08, /* 0x3E74442D, 0x00000000 */
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diff changeset
244 5.39030252995776476554e-15, /* 0x3CF84698, 0x80000000 */
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diff changeset
245 3.28200341580791294123e-22, /* 0x3B78CC51, 0x60000000 */
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246 1.27065575308067607349e-29, /* 0x39F01B83, 0x80000000 */
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247 1.22933308981111328932e-36, /* 0x387A2520, 0x40000000 */
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248 2.73370053816464559624e-44, /* 0x36E38222, 0x80000000 */
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249 2.16741683877804819444e-51, /* 0x3569F31D, 0x00000000 */
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250 };
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251
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252 static const double
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253 zeroB = 0.0,
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254 one = 1.0,
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255 two24B = 1.67772160000000000000e+07, /* 0x41700000, 0x00000000 */
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parents:
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256 twon24 = 5.96046447753906250000e-08; /* 0x3E700000, 0x00000000 */
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257
1485
fb57d4cf76c2 6931180: Migration to recent versions of MS Platform SDK
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parents: 0
diff changeset
258 static SAFEBUF int __kernel_rem_pio2(double *x, double *y, int e0, int nx, int prec, const int *ipio2) {
0
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259 int jz,jx,jv,jp,jk,carry,n,iq[20],i,j,k,m,q0,ih;
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260 double z,fw,f[20],fq[20],q[20];
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261
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262 /* initialize jk*/
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263 jk = init_jk[prec];
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264 jp = jk;
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265
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parents:
diff changeset
266 /* determine jx,jv,q0, note that 3>q0 */
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267 jx = nx-1;
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268 jv = (e0-3)/24; if(jv<0) jv=0;
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269 q0 = e0-24*(jv+1);
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270
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diff changeset
271 /* set up f[0] to f[jx+jk] where f[jx+jk] = ipio2[jv+jk] */
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parents:
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272 j = jv-jx; m = jx+jk;
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parents:
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273 for(i=0;i<=m;i++,j++) f[i] = (j<0)? zeroB : (double) ipio2[j];
a61af66fc99e Initial load
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274
a61af66fc99e Initial load
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parents:
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275 /* compute q[0],q[1],...q[jk] */
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parents:
diff changeset
276 for (i=0;i<=jk;i++) {
a61af66fc99e Initial load
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277 for(j=0,fw=0.0;j<=jx;j++) fw += x[j]*f[jx+i-j]; q[i] = fw;
a61af66fc99e Initial load
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parents:
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278 }
a61af66fc99e Initial load
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279
a61af66fc99e Initial load
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280 jz = jk;
a61af66fc99e Initial load
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281 recompute:
a61af66fc99e Initial load
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parents:
diff changeset
282 /* distill q[] into iq[] reversingly */
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parents:
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283 for(i=0,j=jz,z=q[jz];j>0;i++,j--) {
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parents:
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284 fw = (double)((int)(twon24* z));
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285 iq[i] = (int)(z-two24B*fw);
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286 z = q[j-1]+fw;
a61af66fc99e Initial load
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287 }
a61af66fc99e Initial load
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288
a61af66fc99e Initial load
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289 /* compute n */
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290 z = scalbnA(z,q0); /* actual value of z */
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291 z -= 8.0*floor(z*0.125); /* trim off integer >= 8 */
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292 n = (int) z;
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293 z -= (double)n;
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294 ih = 0;
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295 if(q0>0) { /* need iq[jz-1] to determine n */
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parents:
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296 i = (iq[jz-1]>>(24-q0)); n += i;
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parents:
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297 iq[jz-1] -= i<<(24-q0);
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298 ih = iq[jz-1]>>(23-q0);
a61af66fc99e Initial load
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parents:
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299 }
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300 else if(q0==0) ih = iq[jz-1]>>23;
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301 else if(z>=0.5) ih=2;
a61af66fc99e Initial load
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302
a61af66fc99e Initial load
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303 if(ih>0) { /* q > 0.5 */
a61af66fc99e Initial load
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parents:
diff changeset
304 n += 1; carry = 0;
a61af66fc99e Initial load
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parents:
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305 for(i=0;i<jz ;i++) { /* compute 1-q */
a61af66fc99e Initial load
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parents:
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306 j = iq[i];
a61af66fc99e Initial load
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parents:
diff changeset
307 if(carry==0) {
a61af66fc99e Initial load
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parents:
diff changeset
308 if(j!=0) {
a61af66fc99e Initial load
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parents:
diff changeset
309 carry = 1; iq[i] = 0x1000000- j;
a61af66fc99e Initial load
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parents:
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310 }
a61af66fc99e Initial load
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311 } else iq[i] = 0xffffff - j;
a61af66fc99e Initial load
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parents:
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312 }
a61af66fc99e Initial load
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parents:
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313 if(q0>0) { /* rare case: chance is 1 in 12 */
a61af66fc99e Initial load
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parents:
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314 switch(q0) {
a61af66fc99e Initial load
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parents:
diff changeset
315 case 1:
a61af66fc99e Initial load
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parents:
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316 iq[jz-1] &= 0x7fffff; break;
a61af66fc99e Initial load
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parents:
diff changeset
317 case 2:
a61af66fc99e Initial load
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diff changeset
318 iq[jz-1] &= 0x3fffff; break;
a61af66fc99e Initial load
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parents:
diff changeset
319 }
a61af66fc99e Initial load
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parents:
diff changeset
320 }
a61af66fc99e Initial load
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parents:
diff changeset
321 if(ih==2) {
a61af66fc99e Initial load
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parents:
diff changeset
322 z = one - z;
a61af66fc99e Initial load
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parents:
diff changeset
323 if(carry!=0) z -= scalbnA(one,q0);
a61af66fc99e Initial load
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parents:
diff changeset
324 }
a61af66fc99e Initial load
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parents:
diff changeset
325 }
a61af66fc99e Initial load
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parents:
diff changeset
326
a61af66fc99e Initial load
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parents:
diff changeset
327 /* check if recomputation is needed */
a61af66fc99e Initial load
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parents:
diff changeset
328 if(z==zeroB) {
a61af66fc99e Initial load
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parents:
diff changeset
329 j = 0;
a61af66fc99e Initial load
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parents:
diff changeset
330 for (i=jz-1;i>=jk;i--) j |= iq[i];
a61af66fc99e Initial load
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parents:
diff changeset
331 if(j==0) { /* need recomputation */
a61af66fc99e Initial load
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parents:
diff changeset
332 for(k=1;iq[jk-k]==0;k++); /* k = no. of terms needed */
a61af66fc99e Initial load
duke
parents:
diff changeset
333
a61af66fc99e Initial load
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parents:
diff changeset
334 for(i=jz+1;i<=jz+k;i++) { /* add q[jz+1] to q[jz+k] */
a61af66fc99e Initial load
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parents:
diff changeset
335 f[jx+i] = (double) ipio2[jv+i];
a61af66fc99e Initial load
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parents:
diff changeset
336 for(j=0,fw=0.0;j<=jx;j++) fw += x[j]*f[jx+i-j];
a61af66fc99e Initial load
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parents:
diff changeset
337 q[i] = fw;
a61af66fc99e Initial load
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parents:
diff changeset
338 }
a61af66fc99e Initial load
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parents:
diff changeset
339 jz += k;
a61af66fc99e Initial load
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parents:
diff changeset
340 goto recompute;
a61af66fc99e Initial load
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parents:
diff changeset
341 }
a61af66fc99e Initial load
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parents:
diff changeset
342 }
a61af66fc99e Initial load
duke
parents:
diff changeset
343
a61af66fc99e Initial load
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parents:
diff changeset
344 /* chop off zero terms */
a61af66fc99e Initial load
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parents:
diff changeset
345 if(z==0.0) {
a61af66fc99e Initial load
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parents:
diff changeset
346 jz -= 1; q0 -= 24;
a61af66fc99e Initial load
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parents:
diff changeset
347 while(iq[jz]==0) { jz--; q0-=24;}
a61af66fc99e Initial load
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parents:
diff changeset
348 } else { /* break z into 24-bit if neccessary */
a61af66fc99e Initial load
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parents:
diff changeset
349 z = scalbnA(z,-q0);
a61af66fc99e Initial load
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parents:
diff changeset
350 if(z>=two24B) {
a61af66fc99e Initial load
duke
parents:
diff changeset
351 fw = (double)((int)(twon24*z));
a61af66fc99e Initial load
duke
parents:
diff changeset
352 iq[jz] = (int)(z-two24B*fw);
a61af66fc99e Initial load
duke
parents:
diff changeset
353 jz += 1; q0 += 24;
a61af66fc99e Initial load
duke
parents:
diff changeset
354 iq[jz] = (int) fw;
a61af66fc99e Initial load
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parents:
diff changeset
355 } else iq[jz] = (int) z ;
a61af66fc99e Initial load
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parents:
diff changeset
356 }
a61af66fc99e Initial load
duke
parents:
diff changeset
357
a61af66fc99e Initial load
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parents:
diff changeset
358 /* convert integer "bit" chunk to floating-point value */
a61af66fc99e Initial load
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parents:
diff changeset
359 fw = scalbnA(one,q0);
a61af66fc99e Initial load
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parents:
diff changeset
360 for(i=jz;i>=0;i--) {
a61af66fc99e Initial load
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parents:
diff changeset
361 q[i] = fw*(double)iq[i]; fw*=twon24;
a61af66fc99e Initial load
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parents:
diff changeset
362 }
a61af66fc99e Initial load
duke
parents:
diff changeset
363
a61af66fc99e Initial load
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parents:
diff changeset
364 /* compute PIo2[0,...,jp]*q[jz,...,0] */
a61af66fc99e Initial load
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parents:
diff changeset
365 for(i=jz;i>=0;i--) {
a61af66fc99e Initial load
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parents:
diff changeset
366 for(fw=0.0,k=0;k<=jp&&k<=jz-i;k++) fw += PIo2[k]*q[i+k];
a61af66fc99e Initial load
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parents:
diff changeset
367 fq[jz-i] = fw;
a61af66fc99e Initial load
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parents:
diff changeset
368 }
a61af66fc99e Initial load
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parents:
diff changeset
369
a61af66fc99e Initial load
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parents:
diff changeset
370 /* compress fq[] into y[] */
a61af66fc99e Initial load
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parents:
diff changeset
371 switch(prec) {
a61af66fc99e Initial load
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parents:
diff changeset
372 case 0:
a61af66fc99e Initial load
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parents:
diff changeset
373 fw = 0.0;
a61af66fc99e Initial load
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parents:
diff changeset
374 for (i=jz;i>=0;i--) fw += fq[i];
a61af66fc99e Initial load
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parents:
diff changeset
375 y[0] = (ih==0)? fw: -fw;
a61af66fc99e Initial load
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parents:
diff changeset
376 break;
a61af66fc99e Initial load
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parents:
diff changeset
377 case 1:
a61af66fc99e Initial load
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parents:
diff changeset
378 case 2:
a61af66fc99e Initial load
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parents:
diff changeset
379 fw = 0.0;
a61af66fc99e Initial load
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parents:
diff changeset
380 for (i=jz;i>=0;i--) fw += fq[i];
a61af66fc99e Initial load
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parents:
diff changeset
381 y[0] = (ih==0)? fw: -fw;
a61af66fc99e Initial load
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parents:
diff changeset
382 fw = fq[0]-fw;
a61af66fc99e Initial load
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parents:
diff changeset
383 for (i=1;i<=jz;i++) fw += fq[i];
a61af66fc99e Initial load
duke
parents:
diff changeset
384 y[1] = (ih==0)? fw: -fw;
a61af66fc99e Initial load
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parents:
diff changeset
385 break;
a61af66fc99e Initial load
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parents:
diff changeset
386 case 3: /* painful */
a61af66fc99e Initial load
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parents:
diff changeset
387 for (i=jz;i>0;i--) {
a61af66fc99e Initial load
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parents:
diff changeset
388 fw = fq[i-1]+fq[i];
a61af66fc99e Initial load
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parents:
diff changeset
389 fq[i] += fq[i-1]-fw;
a61af66fc99e Initial load
duke
parents:
diff changeset
390 fq[i-1] = fw;
a61af66fc99e Initial load
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parents:
diff changeset
391 }
a61af66fc99e Initial load
duke
parents:
diff changeset
392 for (i=jz;i>1;i--) {
a61af66fc99e Initial load
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parents:
diff changeset
393 fw = fq[i-1]+fq[i];
a61af66fc99e Initial load
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parents:
diff changeset
394 fq[i] += fq[i-1]-fw;
a61af66fc99e Initial load
duke
parents:
diff changeset
395 fq[i-1] = fw;
a61af66fc99e Initial load
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parents:
diff changeset
396 }
a61af66fc99e Initial load
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parents:
diff changeset
397 for (fw=0.0,i=jz;i>=2;i--) fw += fq[i];
a61af66fc99e Initial load
duke
parents:
diff changeset
398 if(ih==0) {
a61af66fc99e Initial load
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parents:
diff changeset
399 y[0] = fq[0]; y[1] = fq[1]; y[2] = fw;
a61af66fc99e Initial load
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parents:
diff changeset
400 } else {
a61af66fc99e Initial load
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parents:
diff changeset
401 y[0] = -fq[0]; y[1] = -fq[1]; y[2] = -fw;
a61af66fc99e Initial load
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parents:
diff changeset
402 }
a61af66fc99e Initial load
duke
parents:
diff changeset
403 }
a61af66fc99e Initial load
duke
parents:
diff changeset
404 return n&7;
a61af66fc99e Initial load
duke
parents:
diff changeset
405 }
a61af66fc99e Initial load
duke
parents:
diff changeset
406
a61af66fc99e Initial load
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parents:
diff changeset
407
a61af66fc99e Initial load
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parents:
diff changeset
408 /*
a61af66fc99e Initial load
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parents:
diff changeset
409 * ====================================================
1552
c18cbe5936b8 6941466: Oracle rebranding changes for Hotspot repositories
trims
parents: 1485
diff changeset
410 * Copyright (c) 1993 Oracle and/or its affilates. All rights reserved.
0
a61af66fc99e Initial load
duke
parents:
diff changeset
411 *
a61af66fc99e Initial load
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parents:
diff changeset
412 * Developed at SunPro, a Sun Microsystems, Inc. business.
a61af66fc99e Initial load
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parents:
diff changeset
413 * Permission to use, copy, modify, and distribute this
a61af66fc99e Initial load
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parents:
diff changeset
414 * software is freely granted, provided that this notice
a61af66fc99e Initial load
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parents:
diff changeset
415 * is preserved.
a61af66fc99e Initial load
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parents:
diff changeset
416 * ====================================================
a61af66fc99e Initial load
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parents:
diff changeset
417 *
a61af66fc99e Initial load
duke
parents:
diff changeset
418 */
a61af66fc99e Initial load
duke
parents:
diff changeset
419
a61af66fc99e Initial load
duke
parents:
diff changeset
420 /* __ieee754_rem_pio2(x,y)
a61af66fc99e Initial load
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parents:
diff changeset
421 *
a61af66fc99e Initial load
duke
parents:
diff changeset
422 * return the remainder of x rem pi/2 in y[0]+y[1]
a61af66fc99e Initial load
duke
parents:
diff changeset
423 * use __kernel_rem_pio2()
a61af66fc99e Initial load
duke
parents:
diff changeset
424 */
a61af66fc99e Initial load
duke
parents:
diff changeset
425
a61af66fc99e Initial load
duke
parents:
diff changeset
426 /*
a61af66fc99e Initial load
duke
parents:
diff changeset
427 * Table of constants for 2/pi, 396 Hex digits (476 decimal) of 2/pi
a61af66fc99e Initial load
duke
parents:
diff changeset
428 */
a61af66fc99e Initial load
duke
parents:
diff changeset
429 static const int two_over_pi[] = {
a61af66fc99e Initial load
duke
parents:
diff changeset
430 0xA2F983, 0x6E4E44, 0x1529FC, 0x2757D1, 0xF534DD, 0xC0DB62,
a61af66fc99e Initial load
duke
parents:
diff changeset
431 0x95993C, 0x439041, 0xFE5163, 0xABDEBB, 0xC561B7, 0x246E3A,
a61af66fc99e Initial load
duke
parents:
diff changeset
432 0x424DD2, 0xE00649, 0x2EEA09, 0xD1921C, 0xFE1DEB, 0x1CB129,
a61af66fc99e Initial load
duke
parents:
diff changeset
433 0xA73EE8, 0x8235F5, 0x2EBB44, 0x84E99C, 0x7026B4, 0x5F7E41,
a61af66fc99e Initial load
duke
parents:
diff changeset
434 0x3991D6, 0x398353, 0x39F49C, 0x845F8B, 0xBDF928, 0x3B1FF8,
a61af66fc99e Initial load
duke
parents:
diff changeset
435 0x97FFDE, 0x05980F, 0xEF2F11, 0x8B5A0A, 0x6D1F6D, 0x367ECF,
a61af66fc99e Initial load
duke
parents:
diff changeset
436 0x27CB09, 0xB74F46, 0x3F669E, 0x5FEA2D, 0x7527BA, 0xC7EBE5,
a61af66fc99e Initial load
duke
parents:
diff changeset
437 0xF17B3D, 0x0739F7, 0x8A5292, 0xEA6BFB, 0x5FB11F, 0x8D5D08,
a61af66fc99e Initial load
duke
parents:
diff changeset
438 0x560330, 0x46FC7B, 0x6BABF0, 0xCFBC20, 0x9AF436, 0x1DA9E3,
a61af66fc99e Initial load
duke
parents:
diff changeset
439 0x91615E, 0xE61B08, 0x659985, 0x5F14A0, 0x68408D, 0xFFD880,
a61af66fc99e Initial load
duke
parents:
diff changeset
440 0x4D7327, 0x310606, 0x1556CA, 0x73A8C9, 0x60E27B, 0xC08C6B,
a61af66fc99e Initial load
duke
parents:
diff changeset
441 };
a61af66fc99e Initial load
duke
parents:
diff changeset
442
a61af66fc99e Initial load
duke
parents:
diff changeset
443 static const int npio2_hw[] = {
a61af66fc99e Initial load
duke
parents:
diff changeset
444 0x3FF921FB, 0x400921FB, 0x4012D97C, 0x401921FB, 0x401F6A7A, 0x4022D97C,
a61af66fc99e Initial load
duke
parents:
diff changeset
445 0x4025FDBB, 0x402921FB, 0x402C463A, 0x402F6A7A, 0x4031475C, 0x4032D97C,
a61af66fc99e Initial load
duke
parents:
diff changeset
446 0x40346B9C, 0x4035FDBB, 0x40378FDB, 0x403921FB, 0x403AB41B, 0x403C463A,
a61af66fc99e Initial load
duke
parents:
diff changeset
447 0x403DD85A, 0x403F6A7A, 0x40407E4C, 0x4041475C, 0x4042106C, 0x4042D97C,
a61af66fc99e Initial load
duke
parents:
diff changeset
448 0x4043A28C, 0x40446B9C, 0x404534AC, 0x4045FDBB, 0x4046C6CB, 0x40478FDB,
a61af66fc99e Initial load
duke
parents:
diff changeset
449 0x404858EB, 0x404921FB,
a61af66fc99e Initial load
duke
parents:
diff changeset
450 };
a61af66fc99e Initial load
duke
parents:
diff changeset
451
a61af66fc99e Initial load
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parents:
diff changeset
452 /*
a61af66fc99e Initial load
duke
parents:
diff changeset
453 * invpio2: 53 bits of 2/pi
a61af66fc99e Initial load
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parents:
diff changeset
454 * pio2_1: first 33 bit of pi/2
a61af66fc99e Initial load
duke
parents:
diff changeset
455 * pio2_1t: pi/2 - pio2_1
a61af66fc99e Initial load
duke
parents:
diff changeset
456 * pio2_2: second 33 bit of pi/2
a61af66fc99e Initial load
duke
parents:
diff changeset
457 * pio2_2t: pi/2 - (pio2_1+pio2_2)
a61af66fc99e Initial load
duke
parents:
diff changeset
458 * pio2_3: third 33 bit of pi/2
a61af66fc99e Initial load
duke
parents:
diff changeset
459 * pio2_3t: pi/2 - (pio2_1+pio2_2+pio2_3)
a61af66fc99e Initial load
duke
parents:
diff changeset
460 */
a61af66fc99e Initial load
duke
parents:
diff changeset
461
a61af66fc99e Initial load
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parents:
diff changeset
462 static const double
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parents:
diff changeset
463 zeroA = 0.00000000000000000000e+00, /* 0x00000000, 0x00000000 */
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parents:
diff changeset
464 half = 5.00000000000000000000e-01, /* 0x3FE00000, 0x00000000 */
a61af66fc99e Initial load
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parents:
diff changeset
465 two24A = 1.67772160000000000000e+07, /* 0x41700000, 0x00000000 */
a61af66fc99e Initial load
duke
parents:
diff changeset
466 invpio2 = 6.36619772367581382433e-01, /* 0x3FE45F30, 0x6DC9C883 */
a61af66fc99e Initial load
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parents:
diff changeset
467 pio2_1 = 1.57079632673412561417e+00, /* 0x3FF921FB, 0x54400000 */
a61af66fc99e Initial load
duke
parents:
diff changeset
468 pio2_1t = 6.07710050650619224932e-11, /* 0x3DD0B461, 0x1A626331 */
a61af66fc99e Initial load
duke
parents:
diff changeset
469 pio2_2 = 6.07710050630396597660e-11, /* 0x3DD0B461, 0x1A600000 */
a61af66fc99e Initial load
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parents:
diff changeset
470 pio2_2t = 2.02226624879595063154e-21, /* 0x3BA3198A, 0x2E037073 */
a61af66fc99e Initial load
duke
parents:
diff changeset
471 pio2_3 = 2.02226624871116645580e-21, /* 0x3BA3198A, 0x2E000000 */
a61af66fc99e Initial load
duke
parents:
diff changeset
472 pio2_3t = 8.47842766036889956997e-32; /* 0x397B839A, 0x252049C1 */
a61af66fc99e Initial load
duke
parents:
diff changeset
473
1485
fb57d4cf76c2 6931180: Migration to recent versions of MS Platform SDK
prr
parents: 0
diff changeset
474 static SAFEBUF int __ieee754_rem_pio2(double x, double *y) {
0
a61af66fc99e Initial load
duke
parents:
diff changeset
475 double z,w,t,r,fn;
a61af66fc99e Initial load
duke
parents:
diff changeset
476 double tx[3];
a61af66fc99e Initial load
duke
parents:
diff changeset
477 int e0,i,j,nx,n,ix,hx,i0;
a61af66fc99e Initial load
duke
parents:
diff changeset
478
a61af66fc99e Initial load
duke
parents:
diff changeset
479 i0 = ((*(int*)&two24A)>>30)^1; /* high word index */
a61af66fc99e Initial load
duke
parents:
diff changeset
480 hx = *(i0+(int*)&x); /* high word of x */
a61af66fc99e Initial load
duke
parents:
diff changeset
481 ix = hx&0x7fffffff;
a61af66fc99e Initial load
duke
parents:
diff changeset
482 if(ix<=0x3fe921fb) /* |x| ~<= pi/4 , no need for reduction */
a61af66fc99e Initial load
duke
parents:
diff changeset
483 {y[0] = x; y[1] = 0; return 0;}
a61af66fc99e Initial load
duke
parents:
diff changeset
484 if(ix<0x4002d97c) { /* |x| < 3pi/4, special case with n=+-1 */
a61af66fc99e Initial load
duke
parents:
diff changeset
485 if(hx>0) {
a61af66fc99e Initial load
duke
parents:
diff changeset
486 z = x - pio2_1;
a61af66fc99e Initial load
duke
parents:
diff changeset
487 if(ix!=0x3ff921fb) { /* 33+53 bit pi is good enough */
a61af66fc99e Initial load
duke
parents:
diff changeset
488 y[0] = z - pio2_1t;
a61af66fc99e Initial load
duke
parents:
diff changeset
489 y[1] = (z-y[0])-pio2_1t;
a61af66fc99e Initial load
duke
parents:
diff changeset
490 } else { /* near pi/2, use 33+33+53 bit pi */
a61af66fc99e Initial load
duke
parents:
diff changeset
491 z -= pio2_2;
a61af66fc99e Initial load
duke
parents:
diff changeset
492 y[0] = z - pio2_2t;
a61af66fc99e Initial load
duke
parents:
diff changeset
493 y[1] = (z-y[0])-pio2_2t;
a61af66fc99e Initial load
duke
parents:
diff changeset
494 }
a61af66fc99e Initial load
duke
parents:
diff changeset
495 return 1;
a61af66fc99e Initial load
duke
parents:
diff changeset
496 } else { /* negative x */
a61af66fc99e Initial load
duke
parents:
diff changeset
497 z = x + pio2_1;
a61af66fc99e Initial load
duke
parents:
diff changeset
498 if(ix!=0x3ff921fb) { /* 33+53 bit pi is good enough */
a61af66fc99e Initial load
duke
parents:
diff changeset
499 y[0] = z + pio2_1t;
a61af66fc99e Initial load
duke
parents:
diff changeset
500 y[1] = (z-y[0])+pio2_1t;
a61af66fc99e Initial load
duke
parents:
diff changeset
501 } else { /* near pi/2, use 33+33+53 bit pi */
a61af66fc99e Initial load
duke
parents:
diff changeset
502 z += pio2_2;
a61af66fc99e Initial load
duke
parents:
diff changeset
503 y[0] = z + pio2_2t;
a61af66fc99e Initial load
duke
parents:
diff changeset
504 y[1] = (z-y[0])+pio2_2t;
a61af66fc99e Initial load
duke
parents:
diff changeset
505 }
a61af66fc99e Initial load
duke
parents:
diff changeset
506 return -1;
a61af66fc99e Initial load
duke
parents:
diff changeset
507 }
a61af66fc99e Initial load
duke
parents:
diff changeset
508 }
a61af66fc99e Initial load
duke
parents:
diff changeset
509 if(ix<=0x413921fb) { /* |x| ~<= 2^19*(pi/2), medium size */
a61af66fc99e Initial load
duke
parents:
diff changeset
510 t = fabsd(x);
a61af66fc99e Initial load
duke
parents:
diff changeset
511 n = (int) (t*invpio2+half);
a61af66fc99e Initial load
duke
parents:
diff changeset
512 fn = (double)n;
a61af66fc99e Initial load
duke
parents:
diff changeset
513 r = t-fn*pio2_1;
a61af66fc99e Initial load
duke
parents:
diff changeset
514 w = fn*pio2_1t; /* 1st round good to 85 bit */
a61af66fc99e Initial load
duke
parents:
diff changeset
515 if(n<32&&ix!=npio2_hw[n-1]) {
a61af66fc99e Initial load
duke
parents:
diff changeset
516 y[0] = r-w; /* quick check no cancellation */
a61af66fc99e Initial load
duke
parents:
diff changeset
517 } else {
a61af66fc99e Initial load
duke
parents:
diff changeset
518 j = ix>>20;
a61af66fc99e Initial load
duke
parents:
diff changeset
519 y[0] = r-w;
a61af66fc99e Initial load
duke
parents:
diff changeset
520 i = j-(((*(i0+(int*)&y[0]))>>20)&0x7ff);
a61af66fc99e Initial load
duke
parents:
diff changeset
521 if(i>16) { /* 2nd iteration needed, good to 118 */
a61af66fc99e Initial load
duke
parents:
diff changeset
522 t = r;
a61af66fc99e Initial load
duke
parents:
diff changeset
523 w = fn*pio2_2;
a61af66fc99e Initial load
duke
parents:
diff changeset
524 r = t-w;
a61af66fc99e Initial load
duke
parents:
diff changeset
525 w = fn*pio2_2t-((t-r)-w);
a61af66fc99e Initial load
duke
parents:
diff changeset
526 y[0] = r-w;
a61af66fc99e Initial load
duke
parents:
diff changeset
527 i = j-(((*(i0+(int*)&y[0]))>>20)&0x7ff);
a61af66fc99e Initial load
duke
parents:
diff changeset
528 if(i>49) { /* 3rd iteration need, 151 bits acc */
a61af66fc99e Initial load
duke
parents:
diff changeset
529 t = r; /* will cover all possible cases */
a61af66fc99e Initial load
duke
parents:
diff changeset
530 w = fn*pio2_3;
a61af66fc99e Initial load
duke
parents:
diff changeset
531 r = t-w;
a61af66fc99e Initial load
duke
parents:
diff changeset
532 w = fn*pio2_3t-((t-r)-w);
a61af66fc99e Initial load
duke
parents:
diff changeset
533 y[0] = r-w;
a61af66fc99e Initial load
duke
parents:
diff changeset
534 }
a61af66fc99e Initial load
duke
parents:
diff changeset
535 }
a61af66fc99e Initial load
duke
parents:
diff changeset
536 }
a61af66fc99e Initial load
duke
parents:
diff changeset
537 y[1] = (r-y[0])-w;
a61af66fc99e Initial load
duke
parents:
diff changeset
538 if(hx<0) {y[0] = -y[0]; y[1] = -y[1]; return -n;}
a61af66fc99e Initial load
duke
parents:
diff changeset
539 else return n;
a61af66fc99e Initial load
duke
parents:
diff changeset
540 }
a61af66fc99e Initial load
duke
parents:
diff changeset
541 /*
a61af66fc99e Initial load
duke
parents:
diff changeset
542 * all other (large) arguments
a61af66fc99e Initial load
duke
parents:
diff changeset
543 */
a61af66fc99e Initial load
duke
parents:
diff changeset
544 if(ix>=0x7ff00000) { /* x is inf or NaN */
a61af66fc99e Initial load
duke
parents:
diff changeset
545 y[0]=y[1]=x-x; return 0;
a61af66fc99e Initial load
duke
parents:
diff changeset
546 }
a61af66fc99e Initial load
duke
parents:
diff changeset
547 /* set z = scalbn(|x|,ilogb(x)-23) */
a61af66fc99e Initial load
duke
parents:
diff changeset
548 *(1-i0+(int*)&z) = *(1-i0+(int*)&x);
a61af66fc99e Initial load
duke
parents:
diff changeset
549 e0 = (ix>>20)-1046; /* e0 = ilogb(z)-23; */
a61af66fc99e Initial load
duke
parents:
diff changeset
550 *(i0+(int*)&z) = ix - (e0<<20);
a61af66fc99e Initial load
duke
parents:
diff changeset
551 for(i=0;i<2;i++) {
a61af66fc99e Initial load
duke
parents:
diff changeset
552 tx[i] = (double)((int)(z));
a61af66fc99e Initial load
duke
parents:
diff changeset
553 z = (z-tx[i])*two24A;
a61af66fc99e Initial load
duke
parents:
diff changeset
554 }
a61af66fc99e Initial load
duke
parents:
diff changeset
555 tx[2] = z;
a61af66fc99e Initial load
duke
parents:
diff changeset
556 nx = 3;
a61af66fc99e Initial load
duke
parents:
diff changeset
557 while(tx[nx-1]==zeroA) nx--; /* skip zero term */
a61af66fc99e Initial load
duke
parents:
diff changeset
558 n = __kernel_rem_pio2(tx,y,e0,nx,2,two_over_pi);
a61af66fc99e Initial load
duke
parents:
diff changeset
559 if(hx<0) {y[0] = -y[0]; y[1] = -y[1]; return -n;}
a61af66fc99e Initial load
duke
parents:
diff changeset
560 return n;
a61af66fc99e Initial load
duke
parents:
diff changeset
561 }
a61af66fc99e Initial load
duke
parents:
diff changeset
562
a61af66fc99e Initial load
duke
parents:
diff changeset
563
a61af66fc99e Initial load
duke
parents:
diff changeset
564 /* __kernel_sin( x, y, iy)
a61af66fc99e Initial load
duke
parents:
diff changeset
565 * kernel sin function on [-pi/4, pi/4], pi/4 ~ 0.7854
a61af66fc99e Initial load
duke
parents:
diff changeset
566 * Input x is assumed to be bounded by ~pi/4 in magnitude.
a61af66fc99e Initial load
duke
parents:
diff changeset
567 * Input y is the tail of x.
a61af66fc99e Initial load
duke
parents:
diff changeset
568 * Input iy indicates whether y is 0. (if iy=0, y assume to be 0).
a61af66fc99e Initial load
duke
parents:
diff changeset
569 *
a61af66fc99e Initial load
duke
parents:
diff changeset
570 * Algorithm
a61af66fc99e Initial load
duke
parents:
diff changeset
571 * 1. Since sin(-x) = -sin(x), we need only to consider positive x.
a61af66fc99e Initial load
duke
parents:
diff changeset
572 * 2. if x < 2^-27 (hx<0x3e400000 0), return x with inexact if x!=0.
a61af66fc99e Initial load
duke
parents:
diff changeset
573 * 3. sin(x) is approximated by a polynomial of degree 13 on
a61af66fc99e Initial load
duke
parents:
diff changeset
574 * [0,pi/4]
a61af66fc99e Initial load
duke
parents:
diff changeset
575 * 3 13
a61af66fc99e Initial load
duke
parents:
diff changeset
576 * sin(x) ~ x + S1*x + ... + S6*x
a61af66fc99e Initial load
duke
parents:
diff changeset
577 * where
a61af66fc99e Initial load
duke
parents:
diff changeset
578 *
a61af66fc99e Initial load
duke
parents:
diff changeset
579 * |sin(x) 2 4 6 8 10 12 | -58
a61af66fc99e Initial load
duke
parents:
diff changeset
580 * |----- - (1+S1*x +S2*x +S3*x +S4*x +S5*x +S6*x )| <= 2
a61af66fc99e Initial load
duke
parents:
diff changeset
581 * | x |
a61af66fc99e Initial load
duke
parents:
diff changeset
582 *
a61af66fc99e Initial load
duke
parents:
diff changeset
583 * 4. sin(x+y) = sin(x) + sin'(x')*y
a61af66fc99e Initial load
duke
parents:
diff changeset
584 * ~ sin(x) + (1-x*x/2)*y
a61af66fc99e Initial load
duke
parents:
diff changeset
585 * For better accuracy, let
a61af66fc99e Initial load
duke
parents:
diff changeset
586 * 3 2 2 2 2
a61af66fc99e Initial load
duke
parents:
diff changeset
587 * r = x *(S2+x *(S3+x *(S4+x *(S5+x *S6))))
a61af66fc99e Initial load
duke
parents:
diff changeset
588 * then 3 2
a61af66fc99e Initial load
duke
parents:
diff changeset
589 * sin(x) = x + (S1*x + (x *(r-y/2)+y))
a61af66fc99e Initial load
duke
parents:
diff changeset
590 */
a61af66fc99e Initial load
duke
parents:
diff changeset
591
a61af66fc99e Initial load
duke
parents:
diff changeset
592 static const double
a61af66fc99e Initial load
duke
parents:
diff changeset
593 S1 = -1.66666666666666324348e-01, /* 0xBFC55555, 0x55555549 */
a61af66fc99e Initial load
duke
parents:
diff changeset
594 S2 = 8.33333333332248946124e-03, /* 0x3F811111, 0x1110F8A6 */
a61af66fc99e Initial load
duke
parents:
diff changeset
595 S3 = -1.98412698298579493134e-04, /* 0xBF2A01A0, 0x19C161D5 */
a61af66fc99e Initial load
duke
parents:
diff changeset
596 S4 = 2.75573137070700676789e-06, /* 0x3EC71DE3, 0x57B1FE7D */
a61af66fc99e Initial load
duke
parents:
diff changeset
597 S5 = -2.50507602534068634195e-08, /* 0xBE5AE5E6, 0x8A2B9CEB */
a61af66fc99e Initial load
duke
parents:
diff changeset
598 S6 = 1.58969099521155010221e-10; /* 0x3DE5D93A, 0x5ACFD57C */
a61af66fc99e Initial load
duke
parents:
diff changeset
599
a61af66fc99e Initial load
duke
parents:
diff changeset
600 static double __kernel_sin(double x, double y, int iy)
a61af66fc99e Initial load
duke
parents:
diff changeset
601 {
a61af66fc99e Initial load
duke
parents:
diff changeset
602 double z,r,v;
a61af66fc99e Initial load
duke
parents:
diff changeset
603 int ix;
a61af66fc99e Initial load
duke
parents:
diff changeset
604 ix = __HI(x)&0x7fffffff; /* high word of x */
a61af66fc99e Initial load
duke
parents:
diff changeset
605 if(ix<0x3e400000) /* |x| < 2**-27 */
a61af66fc99e Initial load
duke
parents:
diff changeset
606 {if((int)x==0) return x;} /* generate inexact */
a61af66fc99e Initial load
duke
parents:
diff changeset
607 z = x*x;
a61af66fc99e Initial load
duke
parents:
diff changeset
608 v = z*x;
a61af66fc99e Initial load
duke
parents:
diff changeset
609 r = S2+z*(S3+z*(S4+z*(S5+z*S6)));
a61af66fc99e Initial load
duke
parents:
diff changeset
610 if(iy==0) return x+v*(S1+z*r);
a61af66fc99e Initial load
duke
parents:
diff changeset
611 else return x-((z*(half*y-v*r)-y)-v*S1);
a61af66fc99e Initial load
duke
parents:
diff changeset
612 }
a61af66fc99e Initial load
duke
parents:
diff changeset
613
a61af66fc99e Initial load
duke
parents:
diff changeset
614 /*
a61af66fc99e Initial load
duke
parents:
diff changeset
615 * __kernel_cos( x, y )
a61af66fc99e Initial load
duke
parents:
diff changeset
616 * kernel cos function on [-pi/4, pi/4], pi/4 ~ 0.785398164
a61af66fc99e Initial load
duke
parents:
diff changeset
617 * Input x is assumed to be bounded by ~pi/4 in magnitude.
a61af66fc99e Initial load
duke
parents:
diff changeset
618 * Input y is the tail of x.
a61af66fc99e Initial load
duke
parents:
diff changeset
619 *
a61af66fc99e Initial load
duke
parents:
diff changeset
620 * Algorithm
a61af66fc99e Initial load
duke
parents:
diff changeset
621 * 1. Since cos(-x) = cos(x), we need only to consider positive x.
a61af66fc99e Initial load
duke
parents:
diff changeset
622 * 2. if x < 2^-27 (hx<0x3e400000 0), return 1 with inexact if x!=0.
a61af66fc99e Initial load
duke
parents:
diff changeset
623 * 3. cos(x) is approximated by a polynomial of degree 14 on
a61af66fc99e Initial load
duke
parents:
diff changeset
624 * [0,pi/4]
a61af66fc99e Initial load
duke
parents:
diff changeset
625 * 4 14
a61af66fc99e Initial load
duke
parents:
diff changeset
626 * cos(x) ~ 1 - x*x/2 + C1*x + ... + C6*x
a61af66fc99e Initial load
duke
parents:
diff changeset
627 * where the remez error is
a61af66fc99e Initial load
duke
parents:
diff changeset
628 *
a61af66fc99e Initial load
duke
parents:
diff changeset
629 * | 2 4 6 8 10 12 14 | -58
a61af66fc99e Initial load
duke
parents:
diff changeset
630 * |cos(x)-(1-.5*x +C1*x +C2*x +C3*x +C4*x +C5*x +C6*x )| <= 2
a61af66fc99e Initial load
duke
parents:
diff changeset
631 * | |
a61af66fc99e Initial load
duke
parents:
diff changeset
632 *
a61af66fc99e Initial load
duke
parents:
diff changeset
633 * 4 6 8 10 12 14
a61af66fc99e Initial load
duke
parents:
diff changeset
634 * 4. let r = C1*x +C2*x +C3*x +C4*x +C5*x +C6*x , then
a61af66fc99e Initial load
duke
parents:
diff changeset
635 * cos(x) = 1 - x*x/2 + r
a61af66fc99e Initial load
duke
parents:
diff changeset
636 * since cos(x+y) ~ cos(x) - sin(x)*y
a61af66fc99e Initial load
duke
parents:
diff changeset
637 * ~ cos(x) - x*y,
a61af66fc99e Initial load
duke
parents:
diff changeset
638 * a correction term is necessary in cos(x) and hence
a61af66fc99e Initial load
duke
parents:
diff changeset
639 * cos(x+y) = 1 - (x*x/2 - (r - x*y))
a61af66fc99e Initial load
duke
parents:
diff changeset
640 * For better accuracy when x > 0.3, let qx = |x|/4 with
a61af66fc99e Initial load
duke
parents:
diff changeset
641 * the last 32 bits mask off, and if x > 0.78125, let qx = 0.28125.
a61af66fc99e Initial load
duke
parents:
diff changeset
642 * Then
a61af66fc99e Initial load
duke
parents:
diff changeset
643 * cos(x+y) = (1-qx) - ((x*x/2-qx) - (r-x*y)).
a61af66fc99e Initial load
duke
parents:
diff changeset
644 * Note that 1-qx and (x*x/2-qx) is EXACT here, and the
a61af66fc99e Initial load
duke
parents:
diff changeset
645 * magnitude of the latter is at least a quarter of x*x/2,
a61af66fc99e Initial load
duke
parents:
diff changeset
646 * thus, reducing the rounding error in the subtraction.
a61af66fc99e Initial load
duke
parents:
diff changeset
647 */
a61af66fc99e Initial load
duke
parents:
diff changeset
648
a61af66fc99e Initial load
duke
parents:
diff changeset
649 static const double
a61af66fc99e Initial load
duke
parents:
diff changeset
650 C1 = 4.16666666666666019037e-02, /* 0x3FA55555, 0x5555554C */
a61af66fc99e Initial load
duke
parents:
diff changeset
651 C2 = -1.38888888888741095749e-03, /* 0xBF56C16C, 0x16C15177 */
a61af66fc99e Initial load
duke
parents:
diff changeset
652 C3 = 2.48015872894767294178e-05, /* 0x3EFA01A0, 0x19CB1590 */
a61af66fc99e Initial load
duke
parents:
diff changeset
653 C4 = -2.75573143513906633035e-07, /* 0xBE927E4F, 0x809C52AD */
a61af66fc99e Initial load
duke
parents:
diff changeset
654 C5 = 2.08757232129817482790e-09, /* 0x3E21EE9E, 0xBDB4B1C4 */
a61af66fc99e Initial load
duke
parents:
diff changeset
655 C6 = -1.13596475577881948265e-11; /* 0xBDA8FAE9, 0xBE8838D4 */
a61af66fc99e Initial load
duke
parents:
diff changeset
656
a61af66fc99e Initial load
duke
parents:
diff changeset
657 static double __kernel_cos(double x, double y)
a61af66fc99e Initial load
duke
parents:
diff changeset
658 {
a61af66fc99e Initial load
duke
parents:
diff changeset
659 double a,hz,z,r,qx;
a61af66fc99e Initial load
duke
parents:
diff changeset
660 int ix;
a61af66fc99e Initial load
duke
parents:
diff changeset
661 ix = __HI(x)&0x7fffffff; /* ix = |x|'s high word*/
a61af66fc99e Initial load
duke
parents:
diff changeset
662 if(ix<0x3e400000) { /* if x < 2**27 */
a61af66fc99e Initial load
duke
parents:
diff changeset
663 if(((int)x)==0) return one; /* generate inexact */
a61af66fc99e Initial load
duke
parents:
diff changeset
664 }
a61af66fc99e Initial load
duke
parents:
diff changeset
665 z = x*x;
a61af66fc99e Initial load
duke
parents:
diff changeset
666 r = z*(C1+z*(C2+z*(C3+z*(C4+z*(C5+z*C6)))));
a61af66fc99e Initial load
duke
parents:
diff changeset
667 if(ix < 0x3FD33333) /* if |x| < 0.3 */
a61af66fc99e Initial load
duke
parents:
diff changeset
668 return one - (0.5*z - (z*r - x*y));
a61af66fc99e Initial load
duke
parents:
diff changeset
669 else {
a61af66fc99e Initial load
duke
parents:
diff changeset
670 if(ix > 0x3fe90000) { /* x > 0.78125 */
a61af66fc99e Initial load
duke
parents:
diff changeset
671 qx = 0.28125;
a61af66fc99e Initial load
duke
parents:
diff changeset
672 } else {
a61af66fc99e Initial load
duke
parents:
diff changeset
673 __HI(qx) = ix-0x00200000; /* x/4 */
a61af66fc99e Initial load
duke
parents:
diff changeset
674 __LO(qx) = 0;
a61af66fc99e Initial load
duke
parents:
diff changeset
675 }
a61af66fc99e Initial load
duke
parents:
diff changeset
676 hz = 0.5*z-qx;
a61af66fc99e Initial load
duke
parents:
diff changeset
677 a = one-qx;
a61af66fc99e Initial load
duke
parents:
diff changeset
678 return a - (hz - (z*r-x*y));
a61af66fc99e Initial load
duke
parents:
diff changeset
679 }
a61af66fc99e Initial load
duke
parents:
diff changeset
680 }
a61af66fc99e Initial load
duke
parents:
diff changeset
681
a61af66fc99e Initial load
duke
parents:
diff changeset
682 /* __kernel_tan( x, y, k )
a61af66fc99e Initial load
duke
parents:
diff changeset
683 * kernel tan function on [-pi/4, pi/4], pi/4 ~ 0.7854
a61af66fc99e Initial load
duke
parents:
diff changeset
684 * Input x is assumed to be bounded by ~pi/4 in magnitude.
a61af66fc99e Initial load
duke
parents:
diff changeset
685 * Input y is the tail of x.
a61af66fc99e Initial load
duke
parents:
diff changeset
686 * Input k indicates whether tan (if k=1) or
a61af66fc99e Initial load
duke
parents:
diff changeset
687 * -1/tan (if k= -1) is returned.
a61af66fc99e Initial load
duke
parents:
diff changeset
688 *
a61af66fc99e Initial load
duke
parents:
diff changeset
689 * Algorithm
a61af66fc99e Initial load
duke
parents:
diff changeset
690 * 1. Since tan(-x) = -tan(x), we need only to consider positive x.
a61af66fc99e Initial load
duke
parents:
diff changeset
691 * 2. if x < 2^-28 (hx<0x3e300000 0), return x with inexact if x!=0.
a61af66fc99e Initial load
duke
parents:
diff changeset
692 * 3. tan(x) is approximated by a odd polynomial of degree 27 on
a61af66fc99e Initial load
duke
parents:
diff changeset
693 * [0,0.67434]
a61af66fc99e Initial load
duke
parents:
diff changeset
694 * 3 27
a61af66fc99e Initial load
duke
parents:
diff changeset
695 * tan(x) ~ x + T1*x + ... + T13*x
a61af66fc99e Initial load
duke
parents:
diff changeset
696 * where
a61af66fc99e Initial load
duke
parents:
diff changeset
697 *
a61af66fc99e Initial load
duke
parents:
diff changeset
698 * |tan(x) 2 4 26 | -59.2
a61af66fc99e Initial load
duke
parents:
diff changeset
699 * |----- - (1+T1*x +T2*x +.... +T13*x )| <= 2
a61af66fc99e Initial load
duke
parents:
diff changeset
700 * | x |
a61af66fc99e Initial load
duke
parents:
diff changeset
701 *
a61af66fc99e Initial load
duke
parents:
diff changeset
702 * Note: tan(x+y) = tan(x) + tan'(x)*y
a61af66fc99e Initial load
duke
parents:
diff changeset
703 * ~ tan(x) + (1+x*x)*y
a61af66fc99e Initial load
duke
parents:
diff changeset
704 * Therefore, for better accuracy in computing tan(x+y), let
a61af66fc99e Initial load
duke
parents:
diff changeset
705 * 3 2 2 2 2
a61af66fc99e Initial load
duke
parents:
diff changeset
706 * r = x *(T2+x *(T3+x *(...+x *(T12+x *T13))))
a61af66fc99e Initial load
duke
parents:
diff changeset
707 * then
a61af66fc99e Initial load
duke
parents:
diff changeset
708 * 3 2
a61af66fc99e Initial load
duke
parents:
diff changeset
709 * tan(x+y) = x + (T1*x + (x *(r+y)+y))
a61af66fc99e Initial load
duke
parents:
diff changeset
710 *
a61af66fc99e Initial load
duke
parents:
diff changeset
711 * 4. For x in [0.67434,pi/4], let y = pi/4 - x, then
a61af66fc99e Initial load
duke
parents:
diff changeset
712 * tan(x) = tan(pi/4-y) = (1-tan(y))/(1+tan(y))
a61af66fc99e Initial load
duke
parents:
diff changeset
713 * = 1 - 2*(tan(y) - (tan(y)^2)/(1+tan(y)))
a61af66fc99e Initial load
duke
parents:
diff changeset
714 */
a61af66fc99e Initial load
duke
parents:
diff changeset
715
a61af66fc99e Initial load
duke
parents:
diff changeset
716 static const double
a61af66fc99e Initial load
duke
parents:
diff changeset
717 pio4 = 7.85398163397448278999e-01, /* 0x3FE921FB, 0x54442D18 */
a61af66fc99e Initial load
duke
parents:
diff changeset
718 pio4lo= 3.06161699786838301793e-17, /* 0x3C81A626, 0x33145C07 */
a61af66fc99e Initial load
duke
parents:
diff changeset
719 T[] = {
a61af66fc99e Initial load
duke
parents:
diff changeset
720 3.33333333333334091986e-01, /* 0x3FD55555, 0x55555563 */
a61af66fc99e Initial load
duke
parents:
diff changeset
721 1.33333333333201242699e-01, /* 0x3FC11111, 0x1110FE7A */
a61af66fc99e Initial load
duke
parents:
diff changeset
722 5.39682539762260521377e-02, /* 0x3FABA1BA, 0x1BB341FE */
a61af66fc99e Initial load
duke
parents:
diff changeset
723 2.18694882948595424599e-02, /* 0x3F9664F4, 0x8406D637 */
a61af66fc99e Initial load
duke
parents:
diff changeset
724 8.86323982359930005737e-03, /* 0x3F8226E3, 0xE96E8493 */
a61af66fc99e Initial load
duke
parents:
diff changeset
725 3.59207910759131235356e-03, /* 0x3F6D6D22, 0xC9560328 */
a61af66fc99e Initial load
duke
parents:
diff changeset
726 1.45620945432529025516e-03, /* 0x3F57DBC8, 0xFEE08315 */
a61af66fc99e Initial load
duke
parents:
diff changeset
727 5.88041240820264096874e-04, /* 0x3F4344D8, 0xF2F26501 */
a61af66fc99e Initial load
duke
parents:
diff changeset
728 2.46463134818469906812e-04, /* 0x3F3026F7, 0x1A8D1068 */
a61af66fc99e Initial load
duke
parents:
diff changeset
729 7.81794442939557092300e-05, /* 0x3F147E88, 0xA03792A6 */
a61af66fc99e Initial load
duke
parents:
diff changeset
730 7.14072491382608190305e-05, /* 0x3F12B80F, 0x32F0A7E9 */
a61af66fc99e Initial load
duke
parents:
diff changeset
731 -1.85586374855275456654e-05, /* 0xBEF375CB, 0xDB605373 */
a61af66fc99e Initial load
duke
parents:
diff changeset
732 2.59073051863633712884e-05, /* 0x3EFB2A70, 0x74BF7AD4 */
a61af66fc99e Initial load
duke
parents:
diff changeset
733 };
a61af66fc99e Initial load
duke
parents:
diff changeset
734
a61af66fc99e Initial load
duke
parents:
diff changeset
735 static double __kernel_tan(double x, double y, int iy)
a61af66fc99e Initial load
duke
parents:
diff changeset
736 {
a61af66fc99e Initial load
duke
parents:
diff changeset
737 double z,r,v,w,s;
a61af66fc99e Initial load
duke
parents:
diff changeset
738 int ix,hx;
a61af66fc99e Initial load
duke
parents:
diff changeset
739 hx = __HI(x); /* high word of x */
a61af66fc99e Initial load
duke
parents:
diff changeset
740 ix = hx&0x7fffffff; /* high word of |x| */
a61af66fc99e Initial load
duke
parents:
diff changeset
741 if(ix<0x3e300000) { /* x < 2**-28 */
a61af66fc99e Initial load
duke
parents:
diff changeset
742 if((int)x==0) { /* generate inexact */
a61af66fc99e Initial load
duke
parents:
diff changeset
743 if (((ix | __LO(x)) | (iy + 1)) == 0)
a61af66fc99e Initial load
duke
parents:
diff changeset
744 return one / fabsd(x);
a61af66fc99e Initial load
duke
parents:
diff changeset
745 else {
a61af66fc99e Initial load
duke
parents:
diff changeset
746 if (iy == 1)
a61af66fc99e Initial load
duke
parents:
diff changeset
747 return x;
a61af66fc99e Initial load
duke
parents:
diff changeset
748 else { /* compute -1 / (x+y) carefully */
a61af66fc99e Initial load
duke
parents:
diff changeset
749 double a, t;
a61af66fc99e Initial load
duke
parents:
diff changeset
750
a61af66fc99e Initial load
duke
parents:
diff changeset
751 z = w = x + y;
a61af66fc99e Initial load
duke
parents:
diff changeset
752 __LO(z) = 0;
a61af66fc99e Initial load
duke
parents:
diff changeset
753 v = y - (z - x);
a61af66fc99e Initial load
duke
parents:
diff changeset
754 t = a = -one / w;
a61af66fc99e Initial load
duke
parents:
diff changeset
755 __LO(t) = 0;
a61af66fc99e Initial load
duke
parents:
diff changeset
756 s = one + t * z;
a61af66fc99e Initial load
duke
parents:
diff changeset
757 return t + a * (s + t * v);
a61af66fc99e Initial load
duke
parents:
diff changeset
758 }
a61af66fc99e Initial load
duke
parents:
diff changeset
759 }
a61af66fc99e Initial load
duke
parents:
diff changeset
760 }
a61af66fc99e Initial load
duke
parents:
diff changeset
761 }
a61af66fc99e Initial load
duke
parents:
diff changeset
762 if(ix>=0x3FE59428) { /* |x|>=0.6744 */
a61af66fc99e Initial load
duke
parents:
diff changeset
763 if(hx<0) {x = -x; y = -y;}
a61af66fc99e Initial load
duke
parents:
diff changeset
764 z = pio4-x;
a61af66fc99e Initial load
duke
parents:
diff changeset
765 w = pio4lo-y;
a61af66fc99e Initial load
duke
parents:
diff changeset
766 x = z+w; y = 0.0;
a61af66fc99e Initial load
duke
parents:
diff changeset
767 }
a61af66fc99e Initial load
duke
parents:
diff changeset
768 z = x*x;
a61af66fc99e Initial load
duke
parents:
diff changeset
769 w = z*z;
a61af66fc99e Initial load
duke
parents:
diff changeset
770 /* Break x^5*(T[1]+x^2*T[2]+...) into
a61af66fc99e Initial load
duke
parents:
diff changeset
771 * x^5(T[1]+x^4*T[3]+...+x^20*T[11]) +
a61af66fc99e Initial load
duke
parents:
diff changeset
772 * x^5(x^2*(T[2]+x^4*T[4]+...+x^22*[T12]))
a61af66fc99e Initial load
duke
parents:
diff changeset
773 */
a61af66fc99e Initial load
duke
parents:
diff changeset
774 r = T[1]+w*(T[3]+w*(T[5]+w*(T[7]+w*(T[9]+w*T[11]))));
a61af66fc99e Initial load
duke
parents:
diff changeset
775 v = z*(T[2]+w*(T[4]+w*(T[6]+w*(T[8]+w*(T[10]+w*T[12])))));
a61af66fc99e Initial load
duke
parents:
diff changeset
776 s = z*x;
a61af66fc99e Initial load
duke
parents:
diff changeset
777 r = y + z*(s*(r+v)+y);
a61af66fc99e Initial load
duke
parents:
diff changeset
778 r += T[0]*s;
a61af66fc99e Initial load
duke
parents:
diff changeset
779 w = x+r;
a61af66fc99e Initial load
duke
parents:
diff changeset
780 if(ix>=0x3FE59428) {
a61af66fc99e Initial load
duke
parents:
diff changeset
781 v = (double)iy;
a61af66fc99e Initial load
duke
parents:
diff changeset
782 return (double)(1-((hx>>30)&2))*(v-2.0*(x-(w*w/(w+v)-r)));
a61af66fc99e Initial load
duke
parents:
diff changeset
783 }
a61af66fc99e Initial load
duke
parents:
diff changeset
784 if(iy==1) return w;
a61af66fc99e Initial load
duke
parents:
diff changeset
785 else { /* if allow error up to 2 ulp,
a61af66fc99e Initial load
duke
parents:
diff changeset
786 simply return -1.0/(x+r) here */
a61af66fc99e Initial load
duke
parents:
diff changeset
787 /* compute -1.0/(x+r) accurately */
a61af66fc99e Initial load
duke
parents:
diff changeset
788 double a,t;
a61af66fc99e Initial load
duke
parents:
diff changeset
789 z = w;
a61af66fc99e Initial load
duke
parents:
diff changeset
790 __LO(z) = 0;
a61af66fc99e Initial load
duke
parents:
diff changeset
791 v = r-(z - x); /* z+v = r+x */
a61af66fc99e Initial load
duke
parents:
diff changeset
792 t = a = -1.0/w; /* a = -1.0/w */
a61af66fc99e Initial load
duke
parents:
diff changeset
793 __LO(t) = 0;
a61af66fc99e Initial load
duke
parents:
diff changeset
794 s = 1.0+t*z;
a61af66fc99e Initial load
duke
parents:
diff changeset
795 return t+a*(s+t*v);
a61af66fc99e Initial load
duke
parents:
diff changeset
796 }
a61af66fc99e Initial load
duke
parents:
diff changeset
797 }
a61af66fc99e Initial load
duke
parents:
diff changeset
798
a61af66fc99e Initial load
duke
parents:
diff changeset
799
a61af66fc99e Initial load
duke
parents:
diff changeset
800 //----------------------------------------------------------------------
a61af66fc99e Initial load
duke
parents:
diff changeset
801 //
a61af66fc99e Initial load
duke
parents:
diff changeset
802 // Routines for new sin/cos implementation
a61af66fc99e Initial load
duke
parents:
diff changeset
803 //
a61af66fc99e Initial load
duke
parents:
diff changeset
804 //----------------------------------------------------------------------
a61af66fc99e Initial load
duke
parents:
diff changeset
805
a61af66fc99e Initial load
duke
parents:
diff changeset
806 /* sin(x)
a61af66fc99e Initial load
duke
parents:
diff changeset
807 * Return sine function of x.
a61af66fc99e Initial load
duke
parents:
diff changeset
808 *
a61af66fc99e Initial load
duke
parents:
diff changeset
809 * kernel function:
a61af66fc99e Initial load
duke
parents:
diff changeset
810 * __kernel_sin ... sine function on [-pi/4,pi/4]
a61af66fc99e Initial load
duke
parents:
diff changeset
811 * __kernel_cos ... cose function on [-pi/4,pi/4]
a61af66fc99e Initial load
duke
parents:
diff changeset
812 * __ieee754_rem_pio2 ... argument reduction routine
a61af66fc99e Initial load
duke
parents:
diff changeset
813 *
a61af66fc99e Initial load
duke
parents:
diff changeset
814 * Method.
a61af66fc99e Initial load
duke
parents:
diff changeset
815 * Let S,C and T denote the sin, cos and tan respectively on
a61af66fc99e Initial load
duke
parents:
diff changeset
816 * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
a61af66fc99e Initial load
duke
parents:
diff changeset
817 * in [-pi/4 , +pi/4], and let n = k mod 4.
a61af66fc99e Initial load
duke
parents:
diff changeset
818 * We have
a61af66fc99e Initial load
duke
parents:
diff changeset
819 *
a61af66fc99e Initial load
duke
parents:
diff changeset
820 * n sin(x) cos(x) tan(x)
a61af66fc99e Initial load
duke
parents:
diff changeset
821 * ----------------------------------------------------------
a61af66fc99e Initial load
duke
parents:
diff changeset
822 * 0 S C T
a61af66fc99e Initial load
duke
parents:
diff changeset
823 * 1 C -S -1/T
a61af66fc99e Initial load
duke
parents:
diff changeset
824 * 2 -S -C T
a61af66fc99e Initial load
duke
parents:
diff changeset
825 * 3 -C S -1/T
a61af66fc99e Initial load
duke
parents:
diff changeset
826 * ----------------------------------------------------------
a61af66fc99e Initial load
duke
parents:
diff changeset
827 *
a61af66fc99e Initial load
duke
parents:
diff changeset
828 * Special cases:
a61af66fc99e Initial load
duke
parents:
diff changeset
829 * Let trig be any of sin, cos, or tan.
a61af66fc99e Initial load
duke
parents:
diff changeset
830 * trig(+-INF) is NaN, with signals;
a61af66fc99e Initial load
duke
parents:
diff changeset
831 * trig(NaN) is that NaN;
a61af66fc99e Initial load
duke
parents:
diff changeset
832 *
a61af66fc99e Initial load
duke
parents:
diff changeset
833 * Accuracy:
a61af66fc99e Initial load
duke
parents:
diff changeset
834 * TRIG(x) returns trig(x) nearly rounded
a61af66fc99e Initial load
duke
parents:
diff changeset
835 */
a61af66fc99e Initial load
duke
parents:
diff changeset
836
a61af66fc99e Initial load
duke
parents:
diff changeset
837 JRT_LEAF(jdouble, SharedRuntime::dsin(jdouble x))
a61af66fc99e Initial load
duke
parents:
diff changeset
838 double y[2],z=0.0;
a61af66fc99e Initial load
duke
parents:
diff changeset
839 int n, ix;
a61af66fc99e Initial load
duke
parents:
diff changeset
840
a61af66fc99e Initial load
duke
parents:
diff changeset
841 /* High word of x. */
a61af66fc99e Initial load
duke
parents:
diff changeset
842 ix = __HI(x);
a61af66fc99e Initial load
duke
parents:
diff changeset
843
a61af66fc99e Initial load
duke
parents:
diff changeset
844 /* |x| ~< pi/4 */
a61af66fc99e Initial load
duke
parents:
diff changeset
845 ix &= 0x7fffffff;
a61af66fc99e Initial load
duke
parents:
diff changeset
846 if(ix <= 0x3fe921fb) return __kernel_sin(x,z,0);
a61af66fc99e Initial load
duke
parents:
diff changeset
847
a61af66fc99e Initial load
duke
parents:
diff changeset
848 /* sin(Inf or NaN) is NaN */
a61af66fc99e Initial load
duke
parents:
diff changeset
849 else if (ix>=0x7ff00000) return x-x;
a61af66fc99e Initial load
duke
parents:
diff changeset
850
a61af66fc99e Initial load
duke
parents:
diff changeset
851 /* argument reduction needed */
a61af66fc99e Initial load
duke
parents:
diff changeset
852 else {
a61af66fc99e Initial load
duke
parents:
diff changeset
853 n = __ieee754_rem_pio2(x,y);
a61af66fc99e Initial load
duke
parents:
diff changeset
854 switch(n&3) {
a61af66fc99e Initial load
duke
parents:
diff changeset
855 case 0: return __kernel_sin(y[0],y[1],1);
a61af66fc99e Initial load
duke
parents:
diff changeset
856 case 1: return __kernel_cos(y[0],y[1]);
a61af66fc99e Initial load
duke
parents:
diff changeset
857 case 2: return -__kernel_sin(y[0],y[1],1);
a61af66fc99e Initial load
duke
parents:
diff changeset
858 default:
a61af66fc99e Initial load
duke
parents:
diff changeset
859 return -__kernel_cos(y[0],y[1]);
a61af66fc99e Initial load
duke
parents:
diff changeset
860 }
a61af66fc99e Initial load
duke
parents:
diff changeset
861 }
a61af66fc99e Initial load
duke
parents:
diff changeset
862 JRT_END
a61af66fc99e Initial load
duke
parents:
diff changeset
863
a61af66fc99e Initial load
duke
parents:
diff changeset
864 /* cos(x)
a61af66fc99e Initial load
duke
parents:
diff changeset
865 * Return cosine function of x.
a61af66fc99e Initial load
duke
parents:
diff changeset
866 *
a61af66fc99e Initial load
duke
parents:
diff changeset
867 * kernel function:
a61af66fc99e Initial load
duke
parents:
diff changeset
868 * __kernel_sin ... sine function on [-pi/4,pi/4]
a61af66fc99e Initial load
duke
parents:
diff changeset
869 * __kernel_cos ... cosine function on [-pi/4,pi/4]
a61af66fc99e Initial load
duke
parents:
diff changeset
870 * __ieee754_rem_pio2 ... argument reduction routine
a61af66fc99e Initial load
duke
parents:
diff changeset
871 *
a61af66fc99e Initial load
duke
parents:
diff changeset
872 * Method.
a61af66fc99e Initial load
duke
parents:
diff changeset
873 * Let S,C and T denote the sin, cos and tan respectively on
a61af66fc99e Initial load
duke
parents:
diff changeset
874 * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
a61af66fc99e Initial load
duke
parents:
diff changeset
875 * in [-pi/4 , +pi/4], and let n = k mod 4.
a61af66fc99e Initial load
duke
parents:
diff changeset
876 * We have
a61af66fc99e Initial load
duke
parents:
diff changeset
877 *
a61af66fc99e Initial load
duke
parents:
diff changeset
878 * n sin(x) cos(x) tan(x)
a61af66fc99e Initial load
duke
parents:
diff changeset
879 * ----------------------------------------------------------
a61af66fc99e Initial load
duke
parents:
diff changeset
880 * 0 S C T
a61af66fc99e Initial load
duke
parents:
diff changeset
881 * 1 C -S -1/T
a61af66fc99e Initial load
duke
parents:
diff changeset
882 * 2 -S -C T
a61af66fc99e Initial load
duke
parents:
diff changeset
883 * 3 -C S -1/T
a61af66fc99e Initial load
duke
parents:
diff changeset
884 * ----------------------------------------------------------
a61af66fc99e Initial load
duke
parents:
diff changeset
885 *
a61af66fc99e Initial load
duke
parents:
diff changeset
886 * Special cases:
a61af66fc99e Initial load
duke
parents:
diff changeset
887 * Let trig be any of sin, cos, or tan.
a61af66fc99e Initial load
duke
parents:
diff changeset
888 * trig(+-INF) is NaN, with signals;
a61af66fc99e Initial load
duke
parents:
diff changeset
889 * trig(NaN) is that NaN;
a61af66fc99e Initial load
duke
parents:
diff changeset
890 *
a61af66fc99e Initial load
duke
parents:
diff changeset
891 * Accuracy:
a61af66fc99e Initial load
duke
parents:
diff changeset
892 * TRIG(x) returns trig(x) nearly rounded
a61af66fc99e Initial load
duke
parents:
diff changeset
893 */
a61af66fc99e Initial load
duke
parents:
diff changeset
894
a61af66fc99e Initial load
duke
parents:
diff changeset
895 JRT_LEAF(jdouble, SharedRuntime::dcos(jdouble x))
a61af66fc99e Initial load
duke
parents:
diff changeset
896 double y[2],z=0.0;
a61af66fc99e Initial load
duke
parents:
diff changeset
897 int n, ix;
a61af66fc99e Initial load
duke
parents:
diff changeset
898
a61af66fc99e Initial load
duke
parents:
diff changeset
899 /* High word of x. */
a61af66fc99e Initial load
duke
parents:
diff changeset
900 ix = __HI(x);
a61af66fc99e Initial load
duke
parents:
diff changeset
901
a61af66fc99e Initial load
duke
parents:
diff changeset
902 /* |x| ~< pi/4 */
a61af66fc99e Initial load
duke
parents:
diff changeset
903 ix &= 0x7fffffff;
a61af66fc99e Initial load
duke
parents:
diff changeset
904 if(ix <= 0x3fe921fb) return __kernel_cos(x,z);
a61af66fc99e Initial load
duke
parents:
diff changeset
905
a61af66fc99e Initial load
duke
parents:
diff changeset
906 /* cos(Inf or NaN) is NaN */
a61af66fc99e Initial load
duke
parents:
diff changeset
907 else if (ix>=0x7ff00000) return x-x;
a61af66fc99e Initial load
duke
parents:
diff changeset
908
a61af66fc99e Initial load
duke
parents:
diff changeset
909 /* argument reduction needed */
a61af66fc99e Initial load
duke
parents:
diff changeset
910 else {
a61af66fc99e Initial load
duke
parents:
diff changeset
911 n = __ieee754_rem_pio2(x,y);
a61af66fc99e Initial load
duke
parents:
diff changeset
912 switch(n&3) {
a61af66fc99e Initial load
duke
parents:
diff changeset
913 case 0: return __kernel_cos(y[0],y[1]);
a61af66fc99e Initial load
duke
parents:
diff changeset
914 case 1: return -__kernel_sin(y[0],y[1],1);
a61af66fc99e Initial load
duke
parents:
diff changeset
915 case 2: return -__kernel_cos(y[0],y[1]);
a61af66fc99e Initial load
duke
parents:
diff changeset
916 default:
a61af66fc99e Initial load
duke
parents:
diff changeset
917 return __kernel_sin(y[0],y[1],1);
a61af66fc99e Initial load
duke
parents:
diff changeset
918 }
a61af66fc99e Initial load
duke
parents:
diff changeset
919 }
a61af66fc99e Initial load
duke
parents:
diff changeset
920 JRT_END
a61af66fc99e Initial load
duke
parents:
diff changeset
921
a61af66fc99e Initial load
duke
parents:
diff changeset
922 /* tan(x)
a61af66fc99e Initial load
duke
parents:
diff changeset
923 * Return tangent function of x.
a61af66fc99e Initial load
duke
parents:
diff changeset
924 *
a61af66fc99e Initial load
duke
parents:
diff changeset
925 * kernel function:
a61af66fc99e Initial load
duke
parents:
diff changeset
926 * __kernel_tan ... tangent function on [-pi/4,pi/4]
a61af66fc99e Initial load
duke
parents:
diff changeset
927 * __ieee754_rem_pio2 ... argument reduction routine
a61af66fc99e Initial load
duke
parents:
diff changeset
928 *
a61af66fc99e Initial load
duke
parents:
diff changeset
929 * Method.
a61af66fc99e Initial load
duke
parents:
diff changeset
930 * Let S,C and T denote the sin, cos and tan respectively on
a61af66fc99e Initial load
duke
parents:
diff changeset
931 * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
a61af66fc99e Initial load
duke
parents:
diff changeset
932 * in [-pi/4 , +pi/4], and let n = k mod 4.
a61af66fc99e Initial load
duke
parents:
diff changeset
933 * We have
a61af66fc99e Initial load
duke
parents:
diff changeset
934 *
a61af66fc99e Initial load
duke
parents:
diff changeset
935 * n sin(x) cos(x) tan(x)
a61af66fc99e Initial load
duke
parents:
diff changeset
936 * ----------------------------------------------------------
a61af66fc99e Initial load
duke
parents:
diff changeset
937 * 0 S C T
a61af66fc99e Initial load
duke
parents:
diff changeset
938 * 1 C -S -1/T
a61af66fc99e Initial load
duke
parents:
diff changeset
939 * 2 -S -C T
a61af66fc99e Initial load
duke
parents:
diff changeset
940 * 3 -C S -1/T
a61af66fc99e Initial load
duke
parents:
diff changeset
941 * ----------------------------------------------------------
a61af66fc99e Initial load
duke
parents:
diff changeset
942 *
a61af66fc99e Initial load
duke
parents:
diff changeset
943 * Special cases:
a61af66fc99e Initial load
duke
parents:
diff changeset
944 * Let trig be any of sin, cos, or tan.
a61af66fc99e Initial load
duke
parents:
diff changeset
945 * trig(+-INF) is NaN, with signals;
a61af66fc99e Initial load
duke
parents:
diff changeset
946 * trig(NaN) is that NaN;
a61af66fc99e Initial load
duke
parents:
diff changeset
947 *
a61af66fc99e Initial load
duke
parents:
diff changeset
948 * Accuracy:
a61af66fc99e Initial load
duke
parents:
diff changeset
949 * TRIG(x) returns trig(x) nearly rounded
a61af66fc99e Initial load
duke
parents:
diff changeset
950 */
a61af66fc99e Initial load
duke
parents:
diff changeset
951
a61af66fc99e Initial load
duke
parents:
diff changeset
952 JRT_LEAF(jdouble, SharedRuntime::dtan(jdouble x))
a61af66fc99e Initial load
duke
parents:
diff changeset
953 double y[2],z=0.0;
a61af66fc99e Initial load
duke
parents:
diff changeset
954 int n, ix;
a61af66fc99e Initial load
duke
parents:
diff changeset
955
a61af66fc99e Initial load
duke
parents:
diff changeset
956 /* High word of x. */
a61af66fc99e Initial load
duke
parents:
diff changeset
957 ix = __HI(x);
a61af66fc99e Initial load
duke
parents:
diff changeset
958
a61af66fc99e Initial load
duke
parents:
diff changeset
959 /* |x| ~< pi/4 */
a61af66fc99e Initial load
duke
parents:
diff changeset
960 ix &= 0x7fffffff;
a61af66fc99e Initial load
duke
parents:
diff changeset
961 if(ix <= 0x3fe921fb) return __kernel_tan(x,z,1);
a61af66fc99e Initial load
duke
parents:
diff changeset
962
a61af66fc99e Initial load
duke
parents:
diff changeset
963 /* tan(Inf or NaN) is NaN */
a61af66fc99e Initial load
duke
parents:
diff changeset
964 else if (ix>=0x7ff00000) return x-x; /* NaN */
a61af66fc99e Initial load
duke
parents:
diff changeset
965
a61af66fc99e Initial load
duke
parents:
diff changeset
966 /* argument reduction needed */
a61af66fc99e Initial load
duke
parents:
diff changeset
967 else {
a61af66fc99e Initial load
duke
parents:
diff changeset
968 n = __ieee754_rem_pio2(x,y);
a61af66fc99e Initial load
duke
parents:
diff changeset
969 return __kernel_tan(y[0],y[1],1-((n&1)<<1)); /* 1 -- n even
a61af66fc99e Initial load
duke
parents:
diff changeset
970 -1 -- n odd */
a61af66fc99e Initial load
duke
parents:
diff changeset
971 }
a61af66fc99e Initial load
duke
parents:
diff changeset
972 JRT_END
a61af66fc99e Initial load
duke
parents:
diff changeset
973
a61af66fc99e Initial load
duke
parents:
diff changeset
974
a61af66fc99e Initial load
duke
parents:
diff changeset
975 #ifdef WIN32
a61af66fc99e Initial load
duke
parents:
diff changeset
976 # pragma optimize ( "", on )
a61af66fc99e Initial load
duke
parents:
diff changeset
977 #endif