1 /*
2 * Copyright (c) 2003, 2015, 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 * @test
26 * @library ..
27 * @bug 4826774 8078586
28 * @summary Numerical tests for hexadecimal inputs to parseDouble, parseFloat
29 * @author Joseph D. Darcy
30 */
31
32 public class ParseHexFloatingPoint {
33 private ParseHexFloatingPoint(){}
34
35 public static final double infinityD = Double.POSITIVE_INFINITY;
36 public static final double NaND = Double.NaN;
37
38 static int test(String testName, String input,
39 double result, double expected) {
40 int failures =0;
41
42 if (Double.compare(result, expected) != 0 ) {
43 System.err.println("Failure for " + testName +
44 ": For input " + input +
45 " expected " + expected +
46 " got " + result + ".");
47 }
48
49 return failures;
50 }
51
52 static int testCase(String input, double expected) {
53 int failures =0;
54
55
56 // Try different combination of letter components
57 input = input.toLowerCase(java.util.Locale.US);
58
59 String [] suffices = {"", "f", "F", "d", "D"};
60 String [] signs = {"", "-", "+"};
61
62 for(int i = 0; i < 2; i++) {
63 String s1 = input;
64 if(i == 1)
65 s1 = s1.replace('x', 'X');
66
67 for(int j = 0; j < 2; j++) {
68 String s2 = s1;
69 if(j == 1)
70 s2 = s2.replace('p', 'P');
71
72 for(int k = 0; k < 2; k++) {
73 String s3 = s2;
74 if(k == 1)
75 s3 = upperCaseHex(s3);
76
77
78 for(int m = 0; m < suffices.length; m++) {
79 String s4 = s3 + suffices[m];
80
81
82 for(int n = 0; n < signs.length; n++) {
83 String s5 = signs[n] + s4;
84
85 double result = Double.parseDouble(s5);
86 failures += test("Double.parseDouble",
87 s5, result, (signs[n].equals("-") ?
88 -expected:
89 expected));
90 }
91 }
92 }
93 }
94 }
95
96 return failures;
97 }
98
99 static String upperCaseHex(String s) {
100 return s.replace('a', 'A').replace('b', 'B').replace('c', 'C').
101 replace('d', 'D').replace('e','E').replace('f', 'F');
102 }
103
104 /*
105 * Test easy and tricky double rounding cases.
106 */
107 static int doubleTests() {
108
109 /*
110 * A String, double pair
111 */
112 class PairSD {
113 public String s;
114 public double d;
115 PairSD(String s, double d) {
116 this.s = s;
117 this.d = d;
118 }
119 }
120 int failures = 0;
121
122
123
124 // Hex strings that convert to three; test basic functionality
125 // of significand and exponent shift adjusts along with the
126 // no-op of adding leading zeros. These cases don't exercise
127 // the rounding code.
128 String leadingZeros = "0x0000000000000000000";
129 String [] threeTests = {
130 "0x.003p12",
131 "0x.006p11",
132 "0x.00cp10",
133 "0x.018p9",
134
135 "0x.3p4",
136 "0x.6p3",
137 "0x.cp2",
138 "0x1.8p1",
139
140 "0x3p0",
141 "0x6.0p-1",
142 "0xc.0p-2",
143 "0x18.0p-3",
144
145 "0x3000000p-24",
146 "0x3.0p0",
147 "0x3.000000p0",
148 };
149 for(int i=0; i < threeTests.length; i++) {
150 String input = threeTests[i];
151 failures += testCase(input, 3.0);
152
153 input.replaceFirst("^0x", leadingZeros);
154 failures += testCase(input, 3.0);
155 }
156
157 long bigExponents [] = {
158 2*Double.MAX_EXPONENT,
159 2*Double.MIN_EXPONENT,
160
161 (long)Integer.MAX_VALUE-1,
162 (long)Integer.MAX_VALUE,
163 (long)Integer.MAX_VALUE+1,
164
165 (long)Integer.MIN_VALUE-1,
166 (long)Integer.MIN_VALUE,
167 (long)Integer.MIN_VALUE+1,
168
169 Long.MAX_VALUE-1,
170 Long.MAX_VALUE,
171
172 Long.MIN_VALUE+1,
173 Long.MIN_VALUE,
174 };
175
176 // Test zero significand with large exponents.
177 for(int i = 0; i < bigExponents.length; i++) {
178 failures += testCase("0x0.0p"+Long.toString(bigExponents[i]) , 0.0);
179 }
180
181 // Test nonzero significand with large exponents.
182 for(int i = 0; i < bigExponents.length; i++) {
183 long exponent = bigExponents[i];
184 failures += testCase("0x10000.0p"+Long.toString(exponent) ,
185 (exponent <0?0.0:infinityD));
186 }
187
188 // Test significands with different lengths and bit patterns.
189 {
190 long signif = 0;
191 for(int i = 1; i <= 0xe; i++) {
192 signif = (signif <<4) | (long)i;
193 failures += testCase("0x"+Long.toHexString(signif)+"p0", signif);
194 }
195 }
196
197 PairSD [] testCases = {
198 new PairSD("0x0.0p0", 0.0/16.0),
199 new PairSD("0x0.1p0", 1.0/16.0),
200 new PairSD("0x0.2p0", 2.0/16.0),
201 new PairSD("0x0.3p0", 3.0/16.0),
202 new PairSD("0x0.4p0", 4.0/16.0),
203 new PairSD("0x0.5p0", 5.0/16.0),
204 new PairSD("0x0.6p0", 6.0/16.0),
205 new PairSD("0x0.7p0", 7.0/16.0),
206 new PairSD("0x0.8p0", 8.0/16.0),
207 new PairSD("0x0.9p0", 9.0/16.0),
208 new PairSD("0x0.ap0", 10.0/16.0),
209 new PairSD("0x0.bp0", 11.0/16.0),
210 new PairSD("0x0.cp0", 12.0/16.0),
211 new PairSD("0x0.dp0", 13.0/16.0),
212 new PairSD("0x0.ep0", 14.0/16.0),
213 new PairSD("0x0.fp0", 15.0/16.0),
214
215 // Half-way case between zero and MIN_VALUE rounds down to
216 // zero
217 new PairSD("0x1.0p-1075", 0.0),
218
219 // Slighly more than half-way case between zero and
220 // MIN_VALUES rounds up to zero.
221 new PairSD("0x1.1p-1075", Double.MIN_VALUE),
222 new PairSD("0x1.000000000001p-1075", Double.MIN_VALUE),
223 new PairSD("0x1.000000000000001p-1075", Double.MIN_VALUE),
224
225 // More subnormal rounding tests
226 new PairSD("0x0.fffffffffffff7fffffp-1022", Math.nextDown(Double.MIN_NORMAL)),
227 new PairSD("0x0.fffffffffffff8p-1022", Double.MIN_NORMAL),
228 new PairSD("0x0.fffffffffffff800000001p-1022",Double.MIN_NORMAL),
229 new PairSD("0x0.fffffffffffff80000000000000001p-1022",Double.MIN_NORMAL),
230 new PairSD("0x1.0p-1022", Double.MIN_NORMAL),
231
232
233 // Large value and overflow rounding tests
234 new PairSD("0x1.fffffffffffffp1023", Double.MAX_VALUE),
235 new PairSD("0x1.fffffffffffff0000000p1023", Double.MAX_VALUE),
236 new PairSD("0x1.fffffffffffff4p1023", Double.MAX_VALUE),
237 new PairSD("0x1.fffffffffffff7fffffp1023", Double.MAX_VALUE),
238 new PairSD("0x1.fffffffffffff8p1023", infinityD),
239 new PairSD("0x1.fffffffffffff8000001p1023", infinityD),
240
241 new PairSD("0x1.ffffffffffffep1023", Math.nextDown(Double.MAX_VALUE)),
242 new PairSD("0x1.ffffffffffffe0000p1023", Math.nextDown(Double.MAX_VALUE)),
243 new PairSD("0x1.ffffffffffffe8p1023", Math.nextDown(Double.MAX_VALUE)),
244 new PairSD("0x1.ffffffffffffe7p1023", Math.nextDown(Double.MAX_VALUE)),
245 new PairSD("0x1.ffffffffffffeffffffp1023", Double.MAX_VALUE),
246 new PairSD("0x1.ffffffffffffe8000001p1023", Double.MAX_VALUE),
247 };
248
249 for (int i = 0; i < testCases.length; i++) {
250 failures += testCase(testCases[i].s,testCases[i].d);
251 }
252
253 failures += significandAlignmentTests();
254
255 {
256 long seed = RandomSeedFactory.getSeed();
257 java.util.Random rand = new java.util.Random(seed);
258 // Consistency check; double => hexadecimal => double
259 // preserves the original value.
260 for(int i = 0; i < 1000; i++) {
261 double d = rand.nextDouble();
262 failures += testCase(Double.toHexString(d), d);
263 }
264 }
265
266 return failures;
267 }
268
269 /*
270 * Verify rounding works the same regardless of how the
271 * significand is aligned on input. A useful extension could be
272 * to have this sort of test for strings near the overflow
273 * threshold.
274 */
275 static int significandAlignmentTests() {
276 int failures = 0;
277 // baseSignif * 2^baseExp = nextDown(2.0)
278 long [] baseSignifs = {
279 0x1ffffffffffffe00L,
280 0x1fffffffffffff00L
281 };
282
283 double [] answers = {
284 Math.nextDown(Math.nextDown(2.0)),
285 Math.nextDown(2.0),
286 2.0
287 };
288
289 int baseExp = -60;
290 int count = 0;
291 for(int i = 0; i < 2; i++) {
292 for(long j = 0; j <= 0xfL; j++) {
293 for(long k = 0; k <= 8; k+= 4) { // k = {0, 4, 8}
294 long base = baseSignifs[i];
295 long testValue = base | (j<<4) | k;
296
297 int offset = 0;
298 // Calculate when significand should be incremented
299 // see table 4.7 in Koren book
300
301 if ((base & 0x100L) == 0L ) { // lsb is 0
302 if ( (j >= 8L) && // round is 1
303 ((j & 0x7L) != 0 || k != 0 ) ) // sticky is 1
304 offset = 1;
305 }
306 else { // lsb is 1
307 if (j >= 8L) // round is 1
308 offset = 1;
309 }
310
311 double expected = answers[i+offset];
312
313 for(int m = -2; m <= 3; m++) {
314 count ++;
315
316 // Form equal value string and evaluate it
317 String s = "0x" +
318 Long.toHexString((m >=0) ?(testValue<<m):(testValue>>(-m))) +
319 "p" + (baseExp - m);
320
321 failures += testCase(s, expected);
322 }
323 }
324 }
325 }
326
327 return failures;
328 }
329
330
331 /*
332 * Test tricky float rounding cases. The code which
333 * reads in a hex string converts the string to a double value.
334 * If a float value is needed, the double value is cast to float.
335 * However, the cast be itself not always guaranteed to return the
336 * right result since:
337 *
338 * 1. hex string => double can discard a sticky bit which would
339 * influence a direct hex string => float conversion.
340 *
341 * 2. hex string => double => float can have a rounding to double
342 * precision which results in a larger float value while a direct
343 * hex string => float conversion would not round up.
344 *
345 * This method includes tests of the latter two possibilities.
346 */
347 static int floatTests(){
348 int failures = 0;
349
350 /*
351 * A String, float pair
352 */
353 class PairSD {
354 public String s;
355 public float f;
356 PairSD(String s, float f) {
357 this.s = s;
358 this.f = f;
359 }
360 }
361
362 String [][] roundingTestCases = {
363 // Target float value hard rouding version
364
365 {"0x1.000000p0", "0x1.0000000000001p0"},
366
367 // Try some values that should round up to nextUp(1.0f)
368 {"0x1.000002p0", "0x1.0000010000001p0"},
369 {"0x1.000002p0", "0x1.00000100000008p0"},
370 {"0x1.000002p0", "0x1.0000010000000fp0"},
371 {"0x1.000002p0", "0x1.00000100000001p0"},
372 {"0x1.000002p0", "0x1.00000100000000000000000000000000000000001p0"},
373 {"0x1.000002p0", "0x1.0000010000000fp0"},
374
375 // Potential double rounding cases
376 {"0x1.000002p0", "0x1.000002fffffffp0"},
377 {"0x1.000002p0", "0x1.000002fffffff8p0"},
378 {"0x1.000002p0", "0x1.000002ffffffffp0"},
379
380 {"0x1.000002p0", "0x1.000002ffff0ffp0"},
381 {"0x1.000002p0", "0x1.000002ffff0ff8p0"},
382 {"0x1.000002p0", "0x1.000002ffff0fffp0"},
383
384
385 {"0x1.000000p0", "0x1.000000fffffffp0"},
386 {"0x1.000000p0", "0x1.000000fffffff8p0"},
387 {"0x1.000000p0", "0x1.000000ffffffffp0"},
388
389 {"0x1.000000p0", "0x1.000000ffffffep0"},
390 {"0x1.000000p0", "0x1.000000ffffffe8p0"},
391 {"0x1.000000p0", "0x1.000000ffffffefp0"},
392
393 // Float subnormal cases
394 {"0x0.000002p-126", "0x0.0000010000001p-126"},
395 {"0x0.000002p-126", "0x0.00000100000000000001p-126"},
396
397 {"0x0.000006p-126", "0x0.0000050000001p-126"},
398 {"0x0.000006p-126", "0x0.00000500000000000001p-126"},
399
400 {"0x0.0p-149", "0x0.7ffffffffffffffp-149"},
401 {"0x1.0p-148", "0x1.3ffffffffffffffp-148"},
402 {"0x1.cp-147", "0x1.bffffffffffffffp-147"},
403
404 {"0x1.fffffcp-127", "0x1.fffffdffffffffp-127"},
405 };
406
407 String [] signs = {"", "-"};
408
409 for(int i = 0; i < roundingTestCases.length; i++) {
410 for(int j = 0; j < signs.length; j++) {
411 String expectedIn = signs[j]+roundingTestCases[i][0];
412 String resultIn = signs[j]+roundingTestCases[i][1];
413
414 float expected = Float.parseFloat(expectedIn);
415 float result = Float.parseFloat(resultIn);
416
417 if( Float.compare(expected, result) != 0) {
418 failures += 1;
419 System.err.println("" + (i+1));
420 System.err.println("Expected = " + Float.toHexString(expected));
421 System.err.println("Rounded = " + Float.toHexString(result));
422 System.err.println("Double = " + Double.toHexString(Double.parseDouble(resultIn)));
423 System.err.println("Input = " + resultIn);
424 System.err.println("");
425 }
426 }
427 }
428
429 return failures;
430 }
431
432 public static void main(String argv[]) {
433 int failures = 0;
434
435 failures += doubleTests();
436 failures += floatTests();
437
438 if (failures != 0) {
439 throw new RuntimeException("" + failures + " failures while " +
440 "testing hexadecimal floating-point " +
441 "parsing.");
442 }
443 }
444
445 }