File: | jdk/src/hotspot/share/runtime/sharedRuntimeTrig.cpp |
Warning: | line 475, column 17 The left operand of '==' is a garbage value due to array index out of bounds |
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1 | /* | |||
2 | * Copyright (c) 2001, 2017, Oracle and/or its affiliates. All rights reserved. | |||
3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. | |||
4 | * | |||
5 | * This code is free software; you can redistribute it and/or modify it | |||
6 | * under the terms of the GNU General Public License version 2 only, as | |||
7 | * published by the Free Software Foundation. | |||
8 | * | |||
9 | * This code is distributed in the hope that it will be useful, but WITHOUT | |||
10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |||
11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |||
12 | * version 2 for more details (a copy is included in the LICENSE file that | |||
13 | * accompanied this code). | |||
14 | * | |||
15 | * You should have received a copy of the GNU General Public License version | |||
16 | * 2 along with this work; if not, write to the Free Software Foundation, | |||
17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | |||
18 | * | |||
19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | |||
20 | * or visit www.oracle.com if you need additional information or have any | |||
21 | * questions. | |||
22 | * | |||
23 | */ | |||
24 | ||||
25 | #include "precompiled.hpp" | |||
26 | #include "jni.h" | |||
27 | #include "runtime/interfaceSupport.inline.hpp" | |||
28 | #include "runtime/sharedRuntime.hpp" | |||
29 | #include "runtime/sharedRuntimeMath.hpp" | |||
30 | ||||
31 | // This file contains copies of the fdlibm routines used by | |||
32 | // StrictMath. It turns out that it is almost always required to use | |||
33 | // these runtime routines; the Intel CPU doesn't meet the Java | |||
34 | // specification for sin/cos outside a certain limited argument range, | |||
35 | // and the SPARC CPU doesn't appear to have sin/cos instructions. It | |||
36 | // also turns out that avoiding the indirect call through function | |||
37 | // pointer out to libjava.so in SharedRuntime speeds these routines up | |||
38 | // by roughly 15% on both Win32/x86 and Solaris/SPARC. | |||
39 | ||||
40 | /* | |||
41 | * __kernel_rem_pio2(x,y,e0,nx,prec,ipio2) | |||
42 | * double x[],y[]; int e0,nx,prec; int ipio2[]; | |||
43 | * | |||
44 | * __kernel_rem_pio2 return the last three digits of N with | |||
45 | * y = x - N*pi/2 | |||
46 | * so that |y| < pi/2. | |||
47 | * | |||
48 | * The method is to compute the integer (mod 8) and fraction parts of | |||
49 | * (2/pi)*x without doing the full multiplication. In general we | |||
50 | * skip the part of the product that are known to be a huge integer ( | |||
51 | * more accurately, = 0 mod 8 ). Thus the number of operations are | |||
52 | * independent of the exponent of the input. | |||
53 | * | |||
54 | * (2/pi) is represented by an array of 24-bit integers in ipio2[]. | |||
55 | * | |||
56 | * Input parameters: | |||
57 | * x[] The input value (must be positive) is broken into nx | |||
58 | * pieces of 24-bit integers in double precision format. | |||
59 | * x[i] will be the i-th 24 bit of x. The scaled exponent | |||
60 | * of x[0] is given in input parameter e0 (i.e., x[0]*2^e0 | |||
61 | * match x's up to 24 bits. | |||
62 | * | |||
63 | * Example of breaking a double positive z into x[0]+x[1]+x[2]: | |||
64 | * e0 = ilogb(z)-23 | |||
65 | * z = scalbn(z,-e0) | |||
66 | * for i = 0,1,2 | |||
67 | * x[i] = floor(z) | |||
68 | * z = (z-x[i])*2**24 | |||
69 | * | |||
70 | * | |||
71 | * y[] ouput result in an array of double precision numbers. | |||
72 | * The dimension of y[] is: | |||
73 | * 24-bit precision 1 | |||
74 | * 53-bit precision 2 | |||
75 | * 64-bit precision 2 | |||
76 | * 113-bit precision 3 | |||
77 | * The actual value is the sum of them. Thus for 113-bit | |||
78 | * precsion, one may have to do something like: | |||
79 | * | |||
80 | * long double t,w,r_head, r_tail; | |||
81 | * t = (long double)y[2] + (long double)y[1]; | |||
82 | * w = (long double)y[0]; | |||
83 | * r_head = t+w; | |||
84 | * r_tail = w - (r_head - t); | |||
85 | * | |||
86 | * e0 The exponent of x[0] | |||
87 | * | |||
88 | * nx dimension of x[] | |||
89 | * | |||
90 | * prec an interger indicating the precision: | |||
91 | * 0 24 bits (single) | |||
92 | * 1 53 bits (double) | |||
93 | * 2 64 bits (extended) | |||
94 | * 3 113 bits (quad) | |||
95 | * | |||
96 | * ipio2[] | |||
97 | * integer array, contains the (24*i)-th to (24*i+23)-th | |||
98 | * bit of 2/pi after binary point. The corresponding | |||
99 | * floating value is | |||
100 | * | |||
101 | * ipio2[i] * 2^(-24(i+1)). | |||
102 | * | |||
103 | * External function: | |||
104 | * double scalbn(), floor(); | |||
105 | * | |||
106 | * | |||
107 | * Here is the description of some local variables: | |||
108 | * | |||
109 | * jk jk+1 is the initial number of terms of ipio2[] needed | |||
110 | * in the computation. The recommended value is 2,3,4, | |||
111 | * 6 for single, double, extended,and quad. | |||
112 | * | |||
113 | * jz local integer variable indicating the number of | |||
114 | * terms of ipio2[] used. | |||
115 | * | |||
116 | * jx nx - 1 | |||
117 | * | |||
118 | * jv index for pointing to the suitable ipio2[] for the | |||
119 | * computation. In general, we want | |||
120 | * ( 2^e0*x[0] * ipio2[jv-1]*2^(-24jv) )/8 | |||
121 | * is an integer. Thus | |||
122 | * e0-3-24*jv >= 0 or (e0-3)/24 >= jv | |||
123 | * Hence jv = max(0,(e0-3)/24). | |||
124 | * | |||
125 | * jp jp+1 is the number of terms in PIo2[] needed, jp = jk. | |||
126 | * | |||
127 | * q[] double array with integral value, representing the | |||
128 | * 24-bits chunk of the product of x and 2/pi. | |||
129 | * | |||
130 | * q0 the corresponding exponent of q[0]. Note that the | |||
131 | * exponent for q[i] would be q0-24*i. | |||
132 | * | |||
133 | * PIo2[] double precision array, obtained by cutting pi/2 | |||
134 | * into 24 bits chunks. | |||
135 | * | |||
136 | * f[] ipio2[] in floating point | |||
137 | * | |||
138 | * iq[] integer array by breaking up q[] in 24-bits chunk. | |||
139 | * | |||
140 | * fq[] final product of x*(2/pi) in fq[0],..,fq[jk] | |||
141 | * | |||
142 | * ih integer. If >0 it indicates q[] is >= 0.5, hence | |||
143 | * it also indicates the *sign* of the result. | |||
144 | * | |||
145 | */ | |||
146 | ||||
147 | ||||
148 | /* | |||
149 | * Constants: | |||
150 | * The hexadecimal values are the intended ones for the following | |||
151 | * constants. The decimal values may be used, provided that the | |||
152 | * compiler will convert from decimal to binary accurately enough | |||
153 | * to produce the hexadecimal values shown. | |||
154 | */ | |||
155 | ||||
156 | ||||
157 | static const int init_jk[] = {2,3,4,6}; /* initial value for jk */ | |||
158 | ||||
159 | static const double PIo2[] = { | |||
160 | 1.57079625129699707031e+00, /* 0x3FF921FB, 0x40000000 */ | |||
161 | 7.54978941586159635335e-08, /* 0x3E74442D, 0x00000000 */ | |||
162 | 5.39030252995776476554e-15, /* 0x3CF84698, 0x80000000 */ | |||
163 | 3.28200341580791294123e-22, /* 0x3B78CC51, 0x60000000 */ | |||
164 | 1.27065575308067607349e-29, /* 0x39F01B83, 0x80000000 */ | |||
165 | 1.22933308981111328932e-36, /* 0x387A2520, 0x40000000 */ | |||
166 | 2.73370053816464559624e-44, /* 0x36E38222, 0x80000000 */ | |||
167 | 2.16741683877804819444e-51, /* 0x3569F31D, 0x00000000 */ | |||
168 | }; | |||
169 | ||||
170 | static const double | |||
171 | zeroB = 0.0, | |||
172 | one = 1.0, | |||
173 | two24B = 1.67772160000000000000e+07, /* 0x41700000, 0x00000000 */ | |||
174 | twon24 = 5.96046447753906250000e-08; /* 0x3E700000, 0x00000000 */ | |||
175 | ||||
176 | static int __kernel_rem_pio2(double *x, double *y, int e0, int nx, int prec, const int *ipio2) { | |||
177 | int jz,jx,jv,jp,jk,carry,n,iq[20],i,j,k,m,q0,ih; | |||
178 | double z,fw,f[20],fq[20],q[20]; | |||
179 | ||||
180 | /* initialize jk*/ | |||
181 | jk = init_jk[prec]; | |||
182 | jp = jk; | |||
183 | ||||
184 | /* determine jx,jv,q0, note that 3>q0 */ | |||
185 | jx = nx-1; | |||
186 | jv = (e0-3)/24; if(jv<0) jv=0; | |||
187 | q0 = e0-24*(jv+1); | |||
188 | ||||
189 | /* set up f[0] to f[jx+jk] where f[jx+jk] = ipio2[jv+jk] */ | |||
190 | j = jv-jx; m = jx+jk; | |||
191 | for(i=0;i<=m;i++,j++) f[i] = (j<0)? zeroB : (double) ipio2[j]; | |||
192 | ||||
193 | /* compute q[0],q[1],...q[jk] */ | |||
194 | for (i=0;i<=jk;i++) { | |||
195 | for(j=0,fw=0.0;j<=jx;j++) fw += x[j]*f[jx+i-j]; q[i] = fw; | |||
196 | } | |||
197 | ||||
198 | jz = jk; | |||
199 | recompute: | |||
200 | /* distill q[] into iq[] reversingly */ | |||
201 | for(i=0,j=jz,z=q[jz];j>0;i++,j--) { | |||
202 | fw = (double)((int)(twon24* z)); | |||
203 | iq[i] = (int)(z-two24B*fw); | |||
204 | z = q[j-1]+fw; | |||
205 | } | |||
206 | ||||
207 | /* compute n */ | |||
208 | z = scalbnA(z,q0); /* actual value of z */ | |||
209 | z -= 8.0*floor(z*0.125); /* trim off integer >= 8 */ | |||
210 | n = (int) z; | |||
211 | z -= (double)n; | |||
212 | ih = 0; | |||
213 | if(q0>0) { /* need iq[jz-1] to determine n */ | |||
214 | i = (iq[jz-1]>>(24-q0)); n += i; | |||
215 | iq[jz-1] -= i<<(24-q0); | |||
216 | ih = iq[jz-1]>>(23-q0); | |||
217 | } | |||
218 | else if(q0==0) ih = iq[jz-1]>>23; | |||
219 | else if(z>=0.5) ih=2; | |||
220 | ||||
221 | if(ih>0) { /* q > 0.5 */ | |||
222 | n += 1; carry = 0; | |||
223 | for(i=0;i<jz ;i++) { /* compute 1-q */ | |||
224 | j = iq[i]; | |||
225 | if(carry==0) { | |||
226 | if(j!=0) { | |||
227 | carry = 1; iq[i] = 0x1000000- j; | |||
228 | } | |||
229 | } else iq[i] = 0xffffff - j; | |||
230 | } | |||
231 | if(q0>0) { /* rare case: chance is 1 in 12 */ | |||
232 | switch(q0) { | |||
233 | case 1: | |||
234 | iq[jz-1] &= 0x7fffff; break; | |||
235 | case 2: | |||
236 | iq[jz-1] &= 0x3fffff; break; | |||
237 | } | |||
238 | } | |||
239 | if(ih==2) { | |||
240 | z = one - z; | |||
241 | if(carry!=0) z -= scalbnA(one,q0); | |||
242 | } | |||
243 | } | |||
244 | ||||
245 | /* check if recomputation is needed */ | |||
246 | if(z==zeroB) { | |||
247 | j = 0; | |||
248 | for (i=jz-1;i>=jk;i--) j |= iq[i]; | |||
249 | if(j==0) { /* need recomputation */ | |||
250 | for(k=1;iq[jk-k]==0;k++); /* k = no. of terms needed */ | |||
251 | ||||
252 | for(i=jz+1;i<=jz+k;i++) { /* add q[jz+1] to q[jz+k] */ | |||
253 | f[jx+i] = (double) ipio2[jv+i]; | |||
254 | for(j=0,fw=0.0;j<=jx;j++) fw += x[j]*f[jx+i-j]; | |||
255 | q[i] = fw; | |||
256 | } | |||
257 | jz += k; | |||
258 | goto recompute; | |||
259 | } | |||
260 | } | |||
261 | ||||
262 | /* chop off zero terms */ | |||
263 | if(z==0.0) { | |||
264 | jz -= 1; q0 -= 24; | |||
265 | while(iq[jz]==0) { jz--; q0-=24;} | |||
266 | } else { /* break z into 24-bit if necessary */ | |||
267 | z = scalbnA(z,-q0); | |||
268 | if(z>=two24B) { | |||
269 | fw = (double)((int)(twon24*z)); | |||
270 | iq[jz] = (int)(z-two24B*fw); | |||
271 | jz += 1; q0 += 24; | |||
272 | iq[jz] = (int) fw; | |||
273 | } else iq[jz] = (int) z ; | |||
274 | } | |||
275 | ||||
276 | /* convert integer "bit" chunk to floating-point value */ | |||
277 | fw = scalbnA(one,q0); | |||
278 | for(i=jz;i>=0;i--) { | |||
279 | q[i] = fw*(double)iq[i]; fw*=twon24; | |||
280 | } | |||
281 | ||||
282 | /* compute PIo2[0,...,jp]*q[jz,...,0] */ | |||
283 | for(i=jz;i>=0;i--) { | |||
284 | for(fw=0.0,k=0;k<=jp&&k<=jz-i;k++) fw += PIo2[k]*q[i+k]; | |||
285 | fq[jz-i] = fw; | |||
286 | } | |||
287 | ||||
288 | /* compress fq[] into y[] */ | |||
289 | switch(prec) { | |||
290 | case 0: | |||
291 | fw = 0.0; | |||
292 | for (i=jz;i>=0;i--) fw += fq[i]; | |||
293 | y[0] = (ih==0)? fw: -fw; | |||
294 | break; | |||
295 | case 1: | |||
296 | case 2: | |||
297 | fw = 0.0; | |||
298 | for (i=jz;i>=0;i--) fw += fq[i]; | |||
299 | y[0] = (ih==0)? fw: -fw; | |||
300 | fw = fq[0]-fw; | |||
301 | for (i=1;i<=jz;i++) fw += fq[i]; | |||
302 | y[1] = (ih==0)? fw: -fw; | |||
303 | break; | |||
304 | case 3: /* painful */ | |||
305 | for (i=jz;i>0;i--) { | |||
306 | fw = fq[i-1]+fq[i]; | |||
307 | fq[i] += fq[i-1]-fw; | |||
308 | fq[i-1] = fw; | |||
309 | } | |||
310 | for (i=jz;i>1;i--) { | |||
311 | fw = fq[i-1]+fq[i]; | |||
312 | fq[i] += fq[i-1]-fw; | |||
313 | fq[i-1] = fw; | |||
314 | } | |||
315 | for (fw=0.0,i=jz;i>=2;i--) fw += fq[i]; | |||
316 | if(ih==0) { | |||
317 | y[0] = fq[0]; y[1] = fq[1]; y[2] = fw; | |||
318 | } else { | |||
319 | y[0] = -fq[0]; y[1] = -fq[1]; y[2] = -fw; | |||
320 | } | |||
321 | } | |||
322 | return n&7; | |||
323 | } | |||
324 | ||||
325 | ||||
326 | /* | |||
327 | * ==================================================== | |||
328 | * Copyright (c) 1993 Oracle and/or its affiliates. All rights reserved. | |||
329 | * | |||
330 | * Developed at SunPro, a Sun Microsystems, Inc. business. | |||
331 | * Permission to use, copy, modify, and distribute this | |||
332 | * software is freely granted, provided that this notice | |||
333 | * is preserved. | |||
334 | * ==================================================== | |||
335 | * | |||
336 | */ | |||
337 | ||||
338 | /* __ieee754_rem_pio2(x,y) | |||
339 | * | |||
340 | * return the remainder of x rem pi/2 in y[0]+y[1] | |||
341 | * use __kernel_rem_pio2() | |||
342 | */ | |||
343 | ||||
344 | /* | |||
345 | * Table of constants for 2/pi, 396 Hex digits (476 decimal) of 2/pi | |||
346 | */ | |||
347 | static const int two_over_pi[] = { | |||
348 | 0xA2F983, 0x6E4E44, 0x1529FC, 0x2757D1, 0xF534DD, 0xC0DB62, | |||
349 | 0x95993C, 0x439041, 0xFE5163, 0xABDEBB, 0xC561B7, 0x246E3A, | |||
350 | 0x424DD2, 0xE00649, 0x2EEA09, 0xD1921C, 0xFE1DEB, 0x1CB129, | |||
351 | 0xA73EE8, 0x8235F5, 0x2EBB44, 0x84E99C, 0x7026B4, 0x5F7E41, | |||
352 | 0x3991D6, 0x398353, 0x39F49C, 0x845F8B, 0xBDF928, 0x3B1FF8, | |||
353 | 0x97FFDE, 0x05980F, 0xEF2F11, 0x8B5A0A, 0x6D1F6D, 0x367ECF, | |||
354 | 0x27CB09, 0xB74F46, 0x3F669E, 0x5FEA2D, 0x7527BA, 0xC7EBE5, | |||
355 | 0xF17B3D, 0x0739F7, 0x8A5292, 0xEA6BFB, 0x5FB11F, 0x8D5D08, | |||
356 | 0x560330, 0x46FC7B, 0x6BABF0, 0xCFBC20, 0x9AF436, 0x1DA9E3, | |||
357 | 0x91615E, 0xE61B08, 0x659985, 0x5F14A0, 0x68408D, 0xFFD880, | |||
358 | 0x4D7327, 0x310606, 0x1556CA, 0x73A8C9, 0x60E27B, 0xC08C6B, | |||
359 | }; | |||
360 | ||||
361 | static const int npio2_hw[] = { | |||
362 | 0x3FF921FB, 0x400921FB, 0x4012D97C, 0x401921FB, 0x401F6A7A, 0x4022D97C, | |||
363 | 0x4025FDBB, 0x402921FB, 0x402C463A, 0x402F6A7A, 0x4031475C, 0x4032D97C, | |||
364 | 0x40346B9C, 0x4035FDBB, 0x40378FDB, 0x403921FB, 0x403AB41B, 0x403C463A, | |||
365 | 0x403DD85A, 0x403F6A7A, 0x40407E4C, 0x4041475C, 0x4042106C, 0x4042D97C, | |||
366 | 0x4043A28C, 0x40446B9C, 0x404534AC, 0x4045FDBB, 0x4046C6CB, 0x40478FDB, | |||
367 | 0x404858EB, 0x404921FB, | |||
368 | }; | |||
369 | ||||
370 | /* | |||
371 | * invpio2: 53 bits of 2/pi | |||
372 | * pio2_1: first 33 bit of pi/2 | |||
373 | * pio2_1t: pi/2 - pio2_1 | |||
374 | * pio2_2: second 33 bit of pi/2 | |||
375 | * pio2_2t: pi/2 - (pio2_1+pio2_2) | |||
376 | * pio2_3: third 33 bit of pi/2 | |||
377 | * pio2_3t: pi/2 - (pio2_1+pio2_2+pio2_3) | |||
378 | */ | |||
379 | ||||
380 | static const double | |||
381 | zeroA = 0.00000000000000000000e+00, /* 0x00000000, 0x00000000 */ | |||
382 | half = 5.00000000000000000000e-01, /* 0x3FE00000, 0x00000000 */ | |||
383 | two24A = 1.67772160000000000000e+07, /* 0x41700000, 0x00000000 */ | |||
384 | invpio2 = 6.36619772367581382433e-01, /* 0x3FE45F30, 0x6DC9C883 */ | |||
385 | pio2_1 = 1.57079632673412561417e+00, /* 0x3FF921FB, 0x54400000 */ | |||
386 | pio2_1t = 6.07710050650619224932e-11, /* 0x3DD0B461, 0x1A626331 */ | |||
387 | pio2_2 = 6.07710050630396597660e-11, /* 0x3DD0B461, 0x1A600000 */ | |||
388 | pio2_2t = 2.02226624879595063154e-21, /* 0x3BA3198A, 0x2E037073 */ | |||
389 | pio2_3 = 2.02226624871116645580e-21, /* 0x3BA3198A, 0x2E000000 */ | |||
390 | pio2_3t = 8.47842766036889956997e-32; /* 0x397B839A, 0x252049C1 */ | |||
391 | ||||
392 | static int __ieee754_rem_pio2(double x, double *y) { | |||
393 | double z,w,t,r,fn; | |||
394 | double tx[3]; | |||
395 | int e0,i,j,nx,n,ix,hx,i0; | |||
396 | ||||
397 | i0 = ((*(int*)&two24A)>>30)^1; /* high word index */ | |||
398 | hx = *(i0+(int*)&x); /* high word of x */ | |||
399 | ix = hx&0x7fffffff; | |||
400 | if(ix<=0x3fe921fb) /* |x| ~<= pi/4 , no need for reduction */ | |||
401 | {y[0] = x; y[1] = 0; return 0;} | |||
402 | if(ix<0x4002d97c) { /* |x| < 3pi/4, special case with n=+-1 */ | |||
403 | if(hx>0) { | |||
404 | z = x - pio2_1; | |||
405 | if(ix!=0x3ff921fb) { /* 33+53 bit pi is good enough */ | |||
406 | y[0] = z - pio2_1t; | |||
407 | y[1] = (z-y[0])-pio2_1t; | |||
408 | } else { /* near pi/2, use 33+33+53 bit pi */ | |||
409 | z -= pio2_2; | |||
410 | y[0] = z - pio2_2t; | |||
411 | y[1] = (z-y[0])-pio2_2t; | |||
412 | } | |||
413 | return 1; | |||
414 | } else { /* negative x */ | |||
415 | z = x + pio2_1; | |||
416 | if(ix!=0x3ff921fb) { /* 33+53 bit pi is good enough */ | |||
417 | y[0] = z + pio2_1t; | |||
418 | y[1] = (z-y[0])+pio2_1t; | |||
419 | } else { /* near pi/2, use 33+33+53 bit pi */ | |||
420 | z += pio2_2; | |||
421 | y[0] = z + pio2_2t; | |||
422 | y[1] = (z-y[0])+pio2_2t; | |||
423 | } | |||
424 | return -1; | |||
425 | } | |||
426 | } | |||
427 | if(ix<=0x413921fb) { /* |x| ~<= 2^19*(pi/2), medium size */ | |||
428 | t = fabsd(x); | |||
429 | n = (int) (t*invpio2+half); | |||
430 | fn = (double)n; | |||
431 | r = t-fn*pio2_1; | |||
432 | w = fn*pio2_1t; /* 1st round good to 85 bit */ | |||
433 | if(n<32&&ix!=npio2_hw[n-1]) { | |||
434 | y[0] = r-w; /* quick check no cancellation */ | |||
435 | } else { | |||
436 | j = ix>>20; | |||
437 | y[0] = r-w; | |||
438 | i = j-(((*(i0+(int*)&y[0]))>>20)&0x7ff); | |||
439 | if(i>16) { /* 2nd iteration needed, good to 118 */ | |||
440 | t = r; | |||
441 | w = fn*pio2_2; | |||
442 | r = t-w; | |||
443 | w = fn*pio2_2t-((t-r)-w); | |||
444 | y[0] = r-w; | |||
445 | i = j-(((*(i0+(int*)&y[0]))>>20)&0x7ff); | |||
446 | if(i>49) { /* 3rd iteration need, 151 bits acc */ | |||
447 | t = r; /* will cover all possible cases */ | |||
448 | w = fn*pio2_3; | |||
449 | r = t-w; | |||
450 | w = fn*pio2_3t-((t-r)-w); | |||
451 | y[0] = r-w; | |||
452 | } | |||
453 | } | |||
454 | } | |||
455 | y[1] = (r-y[0])-w; | |||
456 | if(hx<0) {y[0] = -y[0]; y[1] = -y[1]; return -n;} | |||
457 | else return n; | |||
458 | } | |||
459 | /* | |||
460 | * all other (large) arguments | |||
461 | */ | |||
462 | if(ix>=0x7ff00000) { /* x is inf or NaN */ | |||
463 | y[0]=y[1]=x-x; return 0; | |||
464 | } | |||
465 | /* set z = scalbn(|x|,ilogb(x)-23) */ | |||
466 | *(1-i0+(int*)&z) = *(1-i0+(int*)&x); | |||
467 | e0 = (ix>>20)-1046; /* e0 = ilogb(z)-23; */ | |||
468 | *(i0+(int*)&z) = ix - (e0<<20); | |||
469 | for(i=0;i<2;i++) { | |||
470 | tx[i] = (double)((int)(z)); | |||
471 | z = (z-tx[i])*two24A; | |||
472 | } | |||
473 | tx[2] = z; | |||
474 | nx = 3; | |||
475 | while(tx[nx-1]==zeroA) nx--; /* skip zero term */ | |||
| ||||
476 | n = __kernel_rem_pio2(tx,y,e0,nx,2,two_over_pi); | |||
477 | if(hx<0) {y[0] = -y[0]; y[1] = -y[1]; return -n;} | |||
478 | return n; | |||
479 | } | |||
480 | ||||
481 | ||||
482 | /* __kernel_sin( x, y, iy) | |||
483 | * kernel sin function on [-pi/4, pi/4], pi/4 ~ 0.7854 | |||
484 | * Input x is assumed to be bounded by ~pi/4 in magnitude. | |||
485 | * Input y is the tail of x. | |||
486 | * Input iy indicates whether y is 0. (if iy=0, y assume to be 0). | |||
487 | * | |||
488 | * Algorithm | |||
489 | * 1. Since sin(-x) = -sin(x), we need only to consider positive x. | |||
490 | * 2. if x < 2^-27 (hx<0x3e400000 0), return x with inexact if x!=0. | |||
491 | * 3. sin(x) is approximated by a polynomial of degree 13 on | |||
492 | * [0,pi/4] | |||
493 | * 3 13 | |||
494 | * sin(x) ~ x + S1*x + ... + S6*x | |||
495 | * where | |||
496 | * | |||
497 | * |sin(x) 2 4 6 8 10 12 | -58 | |||
498 | * |----- - (1+S1*x +S2*x +S3*x +S4*x +S5*x +S6*x )| <= 2 | |||
499 | * | x | | |||
500 | * | |||
501 | * 4. sin(x+y) = sin(x) + sin'(x')*y | |||
502 | * ~ sin(x) + (1-x*x/2)*y | |||
503 | * For better accuracy, let | |||
504 | * 3 2 2 2 2 | |||
505 | * r = x *(S2+x *(S3+x *(S4+x *(S5+x *S6)))) | |||
506 | * then 3 2 | |||
507 | * sin(x) = x + (S1*x + (x *(r-y/2)+y)) | |||
508 | */ | |||
509 | ||||
510 | static const double | |||
511 | S1 = -1.66666666666666324348e-01, /* 0xBFC55555, 0x55555549 */ | |||
512 | S2 = 8.33333333332248946124e-03, /* 0x3F811111, 0x1110F8A6 */ | |||
513 | S3 = -1.98412698298579493134e-04, /* 0xBF2A01A0, 0x19C161D5 */ | |||
514 | S4 = 2.75573137070700676789e-06, /* 0x3EC71DE3, 0x57B1FE7D */ | |||
515 | S5 = -2.50507602534068634195e-08, /* 0xBE5AE5E6, 0x8A2B9CEB */ | |||
516 | S6 = 1.58969099521155010221e-10; /* 0x3DE5D93A, 0x5ACFD57C */ | |||
517 | ||||
518 | static double __kernel_sin(double x, double y, int iy) | |||
519 | { | |||
520 | double z,r,v; | |||
521 | int ix; | |||
522 | ix = high(x)&0x7fffffff; /* high word of x */ | |||
523 | if(ix<0x3e400000) /* |x| < 2**-27 */ | |||
524 | {if((int)x==0) return x;} /* generate inexact */ | |||
525 | z = x*x; | |||
526 | v = z*x; | |||
527 | r = S2+z*(S3+z*(S4+z*(S5+z*S6))); | |||
528 | if(iy==0) return x+v*(S1+z*r); | |||
529 | else return x-((z*(half*y-v*r)-y)-v*S1); | |||
530 | } | |||
531 | ||||
532 | /* | |||
533 | * __kernel_cos( x, y ) | |||
534 | * kernel cos function on [-pi/4, pi/4], pi/4 ~ 0.785398164 | |||
535 | * Input x is assumed to be bounded by ~pi/4 in magnitude. | |||
536 | * Input y is the tail of x. | |||
537 | * | |||
538 | * Algorithm | |||
539 | * 1. Since cos(-x) = cos(x), we need only to consider positive x. | |||
540 | * 2. if x < 2^-27 (hx<0x3e400000 0), return 1 with inexact if x!=0. | |||
541 | * 3. cos(x) is approximated by a polynomial of degree 14 on | |||
542 | * [0,pi/4] | |||
543 | * 4 14 | |||
544 | * cos(x) ~ 1 - x*x/2 + C1*x + ... + C6*x | |||
545 | * where the remez error is | |||
546 | * | |||
547 | * | 2 4 6 8 10 12 14 | -58 | |||
548 | * |cos(x)-(1-.5*x +C1*x +C2*x +C3*x +C4*x +C5*x +C6*x )| <= 2 | |||
549 | * | | | |||
550 | * | |||
551 | * 4 6 8 10 12 14 | |||
552 | * 4. let r = C1*x +C2*x +C3*x +C4*x +C5*x +C6*x , then | |||
553 | * cos(x) = 1 - x*x/2 + r | |||
554 | * since cos(x+y) ~ cos(x) - sin(x)*y | |||
555 | * ~ cos(x) - x*y, | |||
556 | * a correction term is necessary in cos(x) and hence | |||
557 | * cos(x+y) = 1 - (x*x/2 - (r - x*y)) | |||
558 | * For better accuracy when x > 0.3, let qx = |x|/4 with | |||
559 | * the last 32 bits mask off, and if x > 0.78125, let qx = 0.28125. | |||
560 | * Then | |||
561 | * cos(x+y) = (1-qx) - ((x*x/2-qx) - (r-x*y)). | |||
562 | * Note that 1-qx and (x*x/2-qx) is EXACT here, and the | |||
563 | * magnitude of the latter is at least a quarter of x*x/2, | |||
564 | * thus, reducing the rounding error in the subtraction. | |||
565 | */ | |||
566 | ||||
567 | static const double | |||
568 | C1 = 4.16666666666666019037e-02, /* 0x3FA55555, 0x5555554C */ | |||
569 | C2 = -1.38888888888741095749e-03, /* 0xBF56C16C, 0x16C15177 */ | |||
570 | C3 = 2.48015872894767294178e-05, /* 0x3EFA01A0, 0x19CB1590 */ | |||
571 | C4 = -2.75573143513906633035e-07, /* 0xBE927E4F, 0x809C52AD */ | |||
572 | C5 = 2.08757232129817482790e-09, /* 0x3E21EE9E, 0xBDB4B1C4 */ | |||
573 | C6 = -1.13596475577881948265e-11; /* 0xBDA8FAE9, 0xBE8838D4 */ | |||
574 | ||||
575 | static double __kernel_cos(double x, double y) | |||
576 | { | |||
577 | double a,h,z,r,qx=0; | |||
578 | int ix; | |||
579 | ix = high(x)&0x7fffffff; /* ix = |x|'s high word*/ | |||
580 | if(ix<0x3e400000) { /* if x < 2**27 */ | |||
581 | if(((int)x)==0) return one; /* generate inexact */ | |||
582 | } | |||
583 | z = x*x; | |||
584 | r = z*(C1+z*(C2+z*(C3+z*(C4+z*(C5+z*C6))))); | |||
585 | if(ix < 0x3FD33333) /* if |x| < 0.3 */ | |||
586 | return one - (0.5*z - (z*r - x*y)); | |||
587 | else { | |||
588 | if(ix > 0x3fe90000) { /* x > 0.78125 */ | |||
589 | qx = 0.28125; | |||
590 | } else { | |||
591 | set_high(&qx, ix-0x00200000); /* x/4 */ | |||
592 | set_low(&qx, 0); | |||
593 | } | |||
594 | h = 0.5*z-qx; | |||
595 | a = one-qx; | |||
596 | return a - (h - (z*r-x*y)); | |||
597 | } | |||
598 | } | |||
599 | ||||
600 | /* __kernel_tan( x, y, k ) | |||
601 | * kernel tan function on [-pi/4, pi/4], pi/4 ~ 0.7854 | |||
602 | * Input x is assumed to be bounded by ~pi/4 in magnitude. | |||
603 | * Input y is the tail of x. | |||
604 | * Input k indicates whether tan (if k=1) or | |||
605 | * -1/tan (if k= -1) is returned. | |||
606 | * | |||
607 | * Algorithm | |||
608 | * 1. Since tan(-x) = -tan(x), we need only to consider positive x. | |||
609 | * 2. if x < 2^-28 (hx<0x3e300000 0), return x with inexact if x!=0. | |||
610 | * 3. tan(x) is approximated by a odd polynomial of degree 27 on | |||
611 | * [0,0.67434] | |||
612 | * 3 27 | |||
613 | * tan(x) ~ x + T1*x + ... + T13*x | |||
614 | * where | |||
615 | * | |||
616 | * |tan(x) 2 4 26 | -59.2 | |||
617 | * |----- - (1+T1*x +T2*x +.... +T13*x )| <= 2 | |||
618 | * | x | | |||
619 | * | |||
620 | * Note: tan(x+y) = tan(x) + tan'(x)*y | |||
621 | * ~ tan(x) + (1+x*x)*y | |||
622 | * Therefore, for better accuracy in computing tan(x+y), let | |||
623 | * 3 2 2 2 2 | |||
624 | * r = x *(T2+x *(T3+x *(...+x *(T12+x *T13)))) | |||
625 | * then | |||
626 | * 3 2 | |||
627 | * tan(x+y) = x + (T1*x + (x *(r+y)+y)) | |||
628 | * | |||
629 | * 4. For x in [0.67434,pi/4], let y = pi/4 - x, then | |||
630 | * tan(x) = tan(pi/4-y) = (1-tan(y))/(1+tan(y)) | |||
631 | * = 1 - 2*(tan(y) - (tan(y)^2)/(1+tan(y))) | |||
632 | */ | |||
633 | ||||
634 | static const double | |||
635 | pio4 = 7.85398163397448278999e-01, /* 0x3FE921FB, 0x54442D18 */ | |||
636 | pio4lo= 3.06161699786838301793e-17, /* 0x3C81A626, 0x33145C07 */ | |||
637 | T[] = { | |||
638 | 3.33333333333334091986e-01, /* 0x3FD55555, 0x55555563 */ | |||
639 | 1.33333333333201242699e-01, /* 0x3FC11111, 0x1110FE7A */ | |||
640 | 5.39682539762260521377e-02, /* 0x3FABA1BA, 0x1BB341FE */ | |||
641 | 2.18694882948595424599e-02, /* 0x3F9664F4, 0x8406D637 */ | |||
642 | 8.86323982359930005737e-03, /* 0x3F8226E3, 0xE96E8493 */ | |||
643 | 3.59207910759131235356e-03, /* 0x3F6D6D22, 0xC9560328 */ | |||
644 | 1.45620945432529025516e-03, /* 0x3F57DBC8, 0xFEE08315 */ | |||
645 | 5.88041240820264096874e-04, /* 0x3F4344D8, 0xF2F26501 */ | |||
646 | 2.46463134818469906812e-04, /* 0x3F3026F7, 0x1A8D1068 */ | |||
647 | 7.81794442939557092300e-05, /* 0x3F147E88, 0xA03792A6 */ | |||
648 | 7.14072491382608190305e-05, /* 0x3F12B80F, 0x32F0A7E9 */ | |||
649 | -1.85586374855275456654e-05, /* 0xBEF375CB, 0xDB605373 */ | |||
650 | 2.59073051863633712884e-05, /* 0x3EFB2A70, 0x74BF7AD4 */ | |||
651 | }; | |||
652 | ||||
653 | static double __kernel_tan(double x, double y, int iy) | |||
654 | { | |||
655 | double z,r,v,w,s; | |||
656 | int ix,hx; | |||
657 | hx = high(x); /* high word of x */ | |||
658 | ix = hx&0x7fffffff; /* high word of |x| */ | |||
659 | if(ix<0x3e300000) { /* x < 2**-28 */ | |||
660 | if((int)x==0) { /* generate inexact */ | |||
661 | if (((ix | low(x)) | (iy + 1)) == 0) | |||
662 | return one / fabsd(x); | |||
663 | else { | |||
664 | if (iy == 1) | |||
665 | return x; | |||
666 | else { /* compute -1 / (x+y) carefully */ | |||
667 | double a, t; | |||
668 | ||||
669 | z = w = x + y; | |||
670 | set_low(&z, 0); | |||
671 | v = y - (z - x); | |||
672 | t = a = -one / w; | |||
673 | set_low(&t, 0); | |||
674 | s = one + t * z; | |||
675 | return t + a * (s + t * v); | |||
676 | } | |||
677 | } | |||
678 | } | |||
679 | } | |||
680 | if(ix>=0x3FE59428) { /* |x|>=0.6744 */ | |||
681 | if(hx<0) {x = -x; y = -y;} | |||
682 | z = pio4-x; | |||
683 | w = pio4lo-y; | |||
684 | x = z+w; y = 0.0; | |||
685 | } | |||
686 | z = x*x; | |||
687 | w = z*z; | |||
688 | /* Break x^5*(T[1]+x^2*T[2]+...) into | |||
689 | * x^5(T[1]+x^4*T[3]+...+x^20*T[11]) + | |||
690 | * x^5(x^2*(T[2]+x^4*T[4]+...+x^22*[T12])) | |||
691 | */ | |||
692 | r = T[1]+w*(T[3]+w*(T[5]+w*(T[7]+w*(T[9]+w*T[11])))); | |||
693 | v = z*(T[2]+w*(T[4]+w*(T[6]+w*(T[8]+w*(T[10]+w*T[12]))))); | |||
694 | s = z*x; | |||
695 | r = y + z*(s*(r+v)+y); | |||
696 | r += T[0]*s; | |||
697 | w = x+r; | |||
698 | if(ix>=0x3FE59428) { | |||
699 | v = (double)iy; | |||
700 | return (double)(1-((hx>>30)&2))*(v-2.0*(x-(w*w/(w+v)-r))); | |||
701 | } | |||
702 | if(iy==1) return w; | |||
703 | else { /* if allow error up to 2 ulp, | |||
704 | simply return -1.0/(x+r) here */ | |||
705 | /* compute -1.0/(x+r) accurately */ | |||
706 | double a,t; | |||
707 | z = w; | |||
708 | set_low(&z, 0); | |||
709 | v = r-(z - x); /* z+v = r+x */ | |||
710 | t = a = -1.0/w; /* a = -1.0/w */ | |||
711 | set_low(&t, 0); | |||
712 | s = 1.0+t*z; | |||
713 | return t+a*(s+t*v); | |||
714 | } | |||
715 | } | |||
716 | ||||
717 | ||||
718 | //---------------------------------------------------------------------- | |||
719 | // | |||
720 | // Routines for new sin/cos implementation | |||
721 | // | |||
722 | //---------------------------------------------------------------------- | |||
723 | ||||
724 | /* sin(x) | |||
725 | * Return sine function of x. | |||
726 | * | |||
727 | * kernel function: | |||
728 | * __kernel_sin ... sine function on [-pi/4,pi/4] | |||
729 | * __kernel_cos ... cose function on [-pi/4,pi/4] | |||
730 | * __ieee754_rem_pio2 ... argument reduction routine | |||
731 | * | |||
732 | * Method. | |||
733 | * Let S,C and T denote the sin, cos and tan respectively on | |||
734 | * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2 | |||
735 | * in [-pi/4 , +pi/4], and let n = k mod 4. | |||
736 | * We have | |||
737 | * | |||
738 | * n sin(x) cos(x) tan(x) | |||
739 | * ---------------------------------------------------------- | |||
740 | * 0 S C T | |||
741 | * 1 C -S -1/T | |||
742 | * 2 -S -C T | |||
743 | * 3 -C S -1/T | |||
744 | * ---------------------------------------------------------- | |||
745 | * | |||
746 | * Special cases: | |||
747 | * Let trig be any of sin, cos, or tan. | |||
748 | * trig(+-INF) is NaN, with signals; | |||
749 | * trig(NaN) is that NaN; | |||
750 | * | |||
751 | * Accuracy: | |||
752 | * TRIG(x) returns trig(x) nearly rounded | |||
753 | */ | |||
754 | ||||
755 | JRT_LEAF(jdouble, SharedRuntime::dsin(jdouble x))jdouble SharedRuntime::dsin(jdouble x) { NoHandleMark __hm; ; os::verify_stack_alignment(); NoSafepointVerifier __nsv; | |||
756 | double y[2],z=0.0; | |||
757 | int n, ix; | |||
758 | ||||
759 | /* High word of x. */ | |||
760 | ix = high(x); | |||
761 | ||||
762 | /* |x| ~< pi/4 */ | |||
763 | ix &= 0x7fffffff; | |||
764 | if(ix <= 0x3fe921fb) return __kernel_sin(x,z,0); | |||
765 | ||||
766 | /* sin(Inf or NaN) is NaN */ | |||
767 | else if (ix>=0x7ff00000) return x-x; | |||
768 | ||||
769 | /* argument reduction needed */ | |||
770 | else { | |||
771 | n = __ieee754_rem_pio2(x,y); | |||
772 | switch(n&3) { | |||
773 | case 0: return __kernel_sin(y[0],y[1],1); | |||
774 | case 1: return __kernel_cos(y[0],y[1]); | |||
775 | case 2: return -__kernel_sin(y[0],y[1],1); | |||
776 | default: | |||
777 | return -__kernel_cos(y[0],y[1]); | |||
778 | } | |||
779 | } | |||
780 | JRT_END} | |||
781 | ||||
782 | /* cos(x) | |||
783 | * Return cosine function of x. | |||
784 | * | |||
785 | * kernel function: | |||
786 | * __kernel_sin ... sine function on [-pi/4,pi/4] | |||
787 | * __kernel_cos ... cosine function on [-pi/4,pi/4] | |||
788 | * __ieee754_rem_pio2 ... argument reduction routine | |||
789 | * | |||
790 | * Method. | |||
791 | * Let S,C and T denote the sin, cos and tan respectively on | |||
792 | * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2 | |||
793 | * in [-pi/4 , +pi/4], and let n = k mod 4. | |||
794 | * We have | |||
795 | * | |||
796 | * n sin(x) cos(x) tan(x) | |||
797 | * ---------------------------------------------------------- | |||
798 | * 0 S C T | |||
799 | * 1 C -S -1/T | |||
800 | * 2 -S -C T | |||
801 | * 3 -C S -1/T | |||
802 | * ---------------------------------------------------------- | |||
803 | * | |||
804 | * Special cases: | |||
805 | * Let trig be any of sin, cos, or tan. | |||
806 | * trig(+-INF) is NaN, with signals; | |||
807 | * trig(NaN) is that NaN; | |||
808 | * | |||
809 | * Accuracy: | |||
810 | * TRIG(x) returns trig(x) nearly rounded | |||
811 | */ | |||
812 | ||||
813 | JRT_LEAF(jdouble, SharedRuntime::dcos(jdouble x))jdouble SharedRuntime::dcos(jdouble x) { NoHandleMark __hm; ; os::verify_stack_alignment(); NoSafepointVerifier __nsv; | |||
814 | double y[2],z=0.0; | |||
815 | int n, ix; | |||
816 | ||||
817 | /* High word of x. */ | |||
818 | ix = high(x); | |||
819 | ||||
820 | /* |x| ~< pi/4 */ | |||
821 | ix &= 0x7fffffff; | |||
822 | if(ix <= 0x3fe921fb) return __kernel_cos(x,z); | |||
823 | ||||
824 | /* cos(Inf or NaN) is NaN */ | |||
825 | else if (ix>=0x7ff00000) return x-x; | |||
826 | ||||
827 | /* argument reduction needed */ | |||
828 | else { | |||
829 | n = __ieee754_rem_pio2(x,y); | |||
830 | switch(n&3) { | |||
831 | case 0: return __kernel_cos(y[0],y[1]); | |||
832 | case 1: return -__kernel_sin(y[0],y[1],1); | |||
833 | case 2: return -__kernel_cos(y[0],y[1]); | |||
834 | default: | |||
835 | return __kernel_sin(y[0],y[1],1); | |||
836 | } | |||
837 | } | |||
838 | JRT_END} | |||
839 | ||||
840 | /* tan(x) | |||
841 | * Return tangent function of x. | |||
842 | * | |||
843 | * kernel function: | |||
844 | * __kernel_tan ... tangent function on [-pi/4,pi/4] | |||
845 | * __ieee754_rem_pio2 ... argument reduction routine | |||
846 | * | |||
847 | * Method. | |||
848 | * Let S,C and T denote the sin, cos and tan respectively on | |||
849 | * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2 | |||
850 | * in [-pi/4 , +pi/4], and let n = k mod 4. | |||
851 | * We have | |||
852 | * | |||
853 | * n sin(x) cos(x) tan(x) | |||
854 | * ---------------------------------------------------------- | |||
855 | * 0 S C T | |||
856 | * 1 C -S -1/T | |||
857 | * 2 -S -C T | |||
858 | * 3 -C S -1/T | |||
859 | * ---------------------------------------------------------- | |||
860 | * | |||
861 | * Special cases: | |||
862 | * Let trig be any of sin, cos, or tan. | |||
863 | * trig(+-INF) is NaN, with signals; | |||
864 | * trig(NaN) is that NaN; | |||
865 | * | |||
866 | * Accuracy: | |||
867 | * TRIG(x) returns trig(x) nearly rounded | |||
868 | */ | |||
869 | ||||
870 | JRT_LEAF(jdouble, SharedRuntime::dtan(jdouble x))jdouble SharedRuntime::dtan(jdouble x) { NoHandleMark __hm; ; os::verify_stack_alignment(); NoSafepointVerifier __nsv; | |||
871 | double y[2],z=0.0; | |||
872 | int n, ix; | |||
873 | ||||
874 | /* High word of x. */ | |||
875 | ix = high(x); | |||
876 | ||||
877 | /* |x| ~< pi/4 */ | |||
878 | ix &= 0x7fffffff; | |||
879 | if(ix <= 0x3fe921fb) return __kernel_tan(x,z,1); | |||
| ||||
880 | ||||
881 | /* tan(Inf or NaN) is NaN */ | |||
882 | else if (ix>=0x7ff00000) return x-x; /* NaN */ | |||
883 | ||||
884 | /* argument reduction needed */ | |||
885 | else { | |||
886 | n = __ieee754_rem_pio2(x,y); | |||
887 | return __kernel_tan(y[0],y[1],1-((n&1)<<1)); /* 1 -- n even | |||
888 | -1 -- n odd */ | |||
889 | } | |||
890 | JRT_END} |