1 // Copyright 2006-2008 the V8 project authors. All rights reserved.
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3 // modification, are permitted provided that the following conditions are
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27 
28 #include <stdlib.h>
29 
30 #include "src/v8.h"
31 
32 #include "src/base/utils/random-number-generator.h"
33 #include "src/bignum.h"
34 #include "src/diy-fp.h"
35 #include "src/double.h"
36 #include "src/strtod.h"
37 #include "test/cctest/cctest.h"
38 
39 using namespace v8::internal;
40 
StringToVector(const char * str)41 static Vector<const char> StringToVector(const char* str) {
42   return Vector<const char>(str, StrLength(str));
43 }
44 
45 
StrtodChar(const char * str,int exponent)46 static double StrtodChar(const char* str, int exponent) {
47   return Strtod(StringToVector(str), exponent);
48 }
49 
50 
TEST(Strtod)51 TEST(Strtod) {
52   Vector<const char> vector;
53 
54   vector = StringToVector("0");
55   CHECK_EQ(0.0, Strtod(vector, 1));
56   CHECK_EQ(0.0, Strtod(vector, 2));
57   CHECK_EQ(0.0, Strtod(vector, -2));
58   CHECK_EQ(0.0, Strtod(vector, -999));
59   CHECK_EQ(0.0, Strtod(vector, +999));
60 
61   vector = StringToVector("1");
62   CHECK_EQ(1.0, Strtod(vector, 0));
63   CHECK_EQ(10.0, Strtod(vector, 1));
64   CHECK_EQ(100.0, Strtod(vector, 2));
65   CHECK_EQ(1e20, Strtod(vector, 20));
66   CHECK_EQ(1e22, Strtod(vector, 22));
67   CHECK_EQ(1e23, Strtod(vector, 23));
68   CHECK_EQ(1e35, Strtod(vector, 35));
69   CHECK_EQ(1e36, Strtod(vector, 36));
70   CHECK_EQ(1e37, Strtod(vector, 37));
71   CHECK_EQ(1e-1, Strtod(vector, -1));
72   CHECK_EQ(1e-2, Strtod(vector, -2));
73   CHECK_EQ(1e-5, Strtod(vector, -5));
74   CHECK_EQ(1e-20, Strtod(vector, -20));
75   CHECK_EQ(1e-22, Strtod(vector, -22));
76   CHECK_EQ(1e-23, Strtod(vector, -23));
77   CHECK_EQ(1e-25, Strtod(vector, -25));
78   CHECK_EQ(1e-39, Strtod(vector, -39));
79 
80   vector = StringToVector("2");
81   CHECK_EQ(2.0, Strtod(vector, 0));
82   CHECK_EQ(20.0, Strtod(vector, 1));
83   CHECK_EQ(200.0, Strtod(vector, 2));
84   CHECK_EQ(2e20, Strtod(vector, 20));
85   CHECK_EQ(2e22, Strtod(vector, 22));
86   CHECK_EQ(2e23, Strtod(vector, 23));
87   CHECK_EQ(2e35, Strtod(vector, 35));
88   CHECK_EQ(2e36, Strtod(vector, 36));
89   CHECK_EQ(2e37, Strtod(vector, 37));
90   CHECK_EQ(2e-1, Strtod(vector, -1));
91   CHECK_EQ(2e-2, Strtod(vector, -2));
92   CHECK_EQ(2e-5, Strtod(vector, -5));
93   CHECK_EQ(2e-20, Strtod(vector, -20));
94   CHECK_EQ(2e-22, Strtod(vector, -22));
95   CHECK_EQ(2e-23, Strtod(vector, -23));
96   CHECK_EQ(2e-25, Strtod(vector, -25));
97   CHECK_EQ(2e-39, Strtod(vector, -39));
98 
99   vector = StringToVector("9");
100   CHECK_EQ(9.0, Strtod(vector, 0));
101   CHECK_EQ(90.0, Strtod(vector, 1));
102   CHECK_EQ(900.0, Strtod(vector, 2));
103   CHECK_EQ(9e20, Strtod(vector, 20));
104   CHECK_EQ(9e22, Strtod(vector, 22));
105   CHECK_EQ(9e23, Strtod(vector, 23));
106   CHECK_EQ(9e35, Strtod(vector, 35));
107   CHECK_EQ(9e36, Strtod(vector, 36));
108   CHECK_EQ(9e37, Strtod(vector, 37));
109   CHECK_EQ(9e-1, Strtod(vector, -1));
110   CHECK_EQ(9e-2, Strtod(vector, -2));
111   CHECK_EQ(9e-5, Strtod(vector, -5));
112   CHECK_EQ(9e-20, Strtod(vector, -20));
113   CHECK_EQ(9e-22, Strtod(vector, -22));
114   CHECK_EQ(9e-23, Strtod(vector, -23));
115   CHECK_EQ(9e-25, Strtod(vector, -25));
116   CHECK_EQ(9e-39, Strtod(vector, -39));
117 
118   vector = StringToVector("12345");
119   CHECK_EQ(12345.0, Strtod(vector, 0));
120   CHECK_EQ(123450.0, Strtod(vector, 1));
121   CHECK_EQ(1234500.0, Strtod(vector, 2));
122   CHECK_EQ(12345e20, Strtod(vector, 20));
123   CHECK_EQ(12345e22, Strtod(vector, 22));
124   CHECK_EQ(12345e23, Strtod(vector, 23));
125   CHECK_EQ(12345e30, Strtod(vector, 30));
126   CHECK_EQ(12345e31, Strtod(vector, 31));
127   CHECK_EQ(12345e32, Strtod(vector, 32));
128   CHECK_EQ(12345e35, Strtod(vector, 35));
129   CHECK_EQ(12345e36, Strtod(vector, 36));
130   CHECK_EQ(12345e37, Strtod(vector, 37));
131   CHECK_EQ(12345e-1, Strtod(vector, -1));
132   CHECK_EQ(12345e-2, Strtod(vector, -2));
133   CHECK_EQ(12345e-5, Strtod(vector, -5));
134   CHECK_EQ(12345e-20, Strtod(vector, -20));
135   CHECK_EQ(12345e-22, Strtod(vector, -22));
136   CHECK_EQ(12345e-23, Strtod(vector, -23));
137   CHECK_EQ(12345e-25, Strtod(vector, -25));
138   CHECK_EQ(12345e-39, Strtod(vector, -39));
139 
140   vector = StringToVector("12345678901234");
141   CHECK_EQ(12345678901234.0, Strtod(vector, 0));
142   CHECK_EQ(123456789012340.0, Strtod(vector, 1));
143   CHECK_EQ(1234567890123400.0, Strtod(vector, 2));
144   CHECK_EQ(12345678901234e20, Strtod(vector, 20));
145   CHECK_EQ(12345678901234e22, Strtod(vector, 22));
146   CHECK_EQ(12345678901234e23, Strtod(vector, 23));
147   CHECK_EQ(12345678901234e30, Strtod(vector, 30));
148   CHECK_EQ(12345678901234e31, Strtod(vector, 31));
149   CHECK_EQ(12345678901234e32, Strtod(vector, 32));
150   CHECK_EQ(12345678901234e35, Strtod(vector, 35));
151   CHECK_EQ(12345678901234e36, Strtod(vector, 36));
152   CHECK_EQ(12345678901234e37, Strtod(vector, 37));
153   CHECK_EQ(12345678901234e-1, Strtod(vector, -1));
154   CHECK_EQ(12345678901234e-2, Strtod(vector, -2));
155   CHECK_EQ(12345678901234e-5, Strtod(vector, -5));
156   CHECK_EQ(12345678901234e-20, Strtod(vector, -20));
157   CHECK_EQ(12345678901234e-22, Strtod(vector, -22));
158   CHECK_EQ(12345678901234e-23, Strtod(vector, -23));
159   CHECK_EQ(12345678901234e-25, Strtod(vector, -25));
160   CHECK_EQ(12345678901234e-39, Strtod(vector, -39));
161 
162   vector = StringToVector("123456789012345");
163   CHECK_EQ(123456789012345.0, Strtod(vector, 0));
164   CHECK_EQ(1234567890123450.0, Strtod(vector, 1));
165   CHECK_EQ(12345678901234500.0, Strtod(vector, 2));
166   CHECK_EQ(123456789012345e20, Strtod(vector, 20));
167   CHECK_EQ(123456789012345e22, Strtod(vector, 22));
168   CHECK_EQ(123456789012345e23, Strtod(vector, 23));
169   CHECK_EQ(123456789012345e35, Strtod(vector, 35));
170   CHECK_EQ(123456789012345e36, Strtod(vector, 36));
171   CHECK_EQ(123456789012345e37, Strtod(vector, 37));
172   CHECK_EQ(123456789012345e39, Strtod(vector, 39));
173   CHECK_EQ(123456789012345e-1, Strtod(vector, -1));
174   CHECK_EQ(123456789012345e-2, Strtod(vector, -2));
175   CHECK_EQ(123456789012345e-5, Strtod(vector, -5));
176   CHECK_EQ(123456789012345e-20, Strtod(vector, -20));
177   CHECK_EQ(123456789012345e-22, Strtod(vector, -22));
178   CHECK_EQ(123456789012345e-23, Strtod(vector, -23));
179   CHECK_EQ(123456789012345e-25, Strtod(vector, -25));
180   CHECK_EQ(123456789012345e-39, Strtod(vector, -39));
181 
182   CHECK_EQ(0.0, StrtodChar("0", 12345));
183   CHECK_EQ(0.0, StrtodChar("", 1324));
184   CHECK_EQ(0.0, StrtodChar("000000000", 123));
185   CHECK_EQ(0.0, StrtodChar("2", -324));
186   CHECK_EQ(4e-324, StrtodChar("3", -324));
187   // It would be more readable to put non-zero literals on the left side (i.e.
188   //   CHECK_EQ(1e-325, StrtodChar("1", -325))), but then Gcc complains that
189   // they are truncated to zero.
190   CHECK_EQ(0.0, StrtodChar("1", -325));
191   CHECK_EQ(0.0, StrtodChar("1", -325));
192   CHECK_EQ(0.0, StrtodChar("20000", -328));
193   CHECK_EQ(40000e-328, StrtodChar("30000", -328));
194   CHECK_EQ(0.0, StrtodChar("10000", -329));
195   CHECK_EQ(0.0, StrtodChar("90000", -329));
196   CHECK_EQ(0.0, StrtodChar("000000001", -325));
197   CHECK_EQ(0.0, StrtodChar("000000001", -325));
198   CHECK_EQ(0.0, StrtodChar("0000000020000", -328));
199   CHECK_EQ(40000e-328, StrtodChar("00000030000", -328));
200   CHECK_EQ(0.0, StrtodChar("0000000010000", -329));
201   CHECK_EQ(0.0, StrtodChar("0000000090000", -329));
202 
203   // It would be more readable to put the literals (and not V8_INFINITY) on the
204   // left side (i.e. CHECK_EQ(1e309, StrtodChar("1", 309))), but then Gcc
205   // complains that the floating constant exceeds range of 'double'.
206   CHECK_EQ(V8_INFINITY, StrtodChar("1", 309));
207   CHECK_EQ(1e308, StrtodChar("1", 308));
208   CHECK_EQ(1234e305, StrtodChar("1234", 305));
209   CHECK_EQ(1234e304, StrtodChar("1234", 304));
210   CHECK_EQ(V8_INFINITY, StrtodChar("18", 307));
211   CHECK_EQ(17e307, StrtodChar("17", 307));
212   CHECK_EQ(V8_INFINITY, StrtodChar("0000001", 309));
213   CHECK_EQ(1e308, StrtodChar("00000001", 308));
214   CHECK_EQ(1234e305, StrtodChar("00000001234", 305));
215   CHECK_EQ(1234e304, StrtodChar("000000001234", 304));
216   CHECK_EQ(V8_INFINITY, StrtodChar("0000000018", 307));
217   CHECK_EQ(17e307, StrtodChar("0000000017", 307));
218   CHECK_EQ(V8_INFINITY, StrtodChar("1000000", 303));
219   CHECK_EQ(1e308, StrtodChar("100000", 303));
220   CHECK_EQ(1234e305, StrtodChar("123400000", 300));
221   CHECK_EQ(1234e304, StrtodChar("123400000", 299));
222   CHECK_EQ(V8_INFINITY, StrtodChar("180000000", 300));
223   CHECK_EQ(17e307, StrtodChar("170000000", 300));
224   CHECK_EQ(V8_INFINITY, StrtodChar("00000001000000", 303));
225   CHECK_EQ(1e308, StrtodChar("000000000000100000", 303));
226   CHECK_EQ(1234e305, StrtodChar("00000000123400000", 300));
227   CHECK_EQ(1234e304, StrtodChar("0000000123400000", 299));
228   CHECK_EQ(V8_INFINITY, StrtodChar("00000000180000000", 300));
229   CHECK_EQ(17e307, StrtodChar("00000000170000000", 300));
230   CHECK_EQ(1.7976931348623157E+308, StrtodChar("17976931348623157", 292));
231   CHECK_EQ(1.7976931348623158E+308, StrtodChar("17976931348623158", 292));
232   CHECK_EQ(V8_INFINITY, StrtodChar("17976931348623159", 292));
233 
234   // The following number is the result of 89255.0/1e22. Both floating-point
235   // numbers can be accurately represented with doubles. However on Linux,x86
236   // the floating-point stack is set to 80bits and the double-rounding
237   // introduces an error.
238   CHECK_EQ(89255e-22, StrtodChar("89255", -22));
239 
240   // Some random values.
241   CHECK_EQ(358416272e-33, StrtodChar("358416272", -33));
242   CHECK_EQ(104110013277974872254e-225,
243            StrtodChar("104110013277974872254", -225));
244 
245   CHECK_EQ(123456789e108, StrtodChar("123456789", 108));
246   CHECK_EQ(123456789e109, StrtodChar("123456789", 109));
247   CHECK_EQ(123456789e110, StrtodChar("123456789", 110));
248   CHECK_EQ(123456789e111, StrtodChar("123456789", 111));
249   CHECK_EQ(123456789e112, StrtodChar("123456789", 112));
250   CHECK_EQ(123456789e113, StrtodChar("123456789", 113));
251   CHECK_EQ(123456789e114, StrtodChar("123456789", 114));
252   CHECK_EQ(123456789e115, StrtodChar("123456789", 115));
253 
254   CHECK_EQ(1234567890123456789012345e108,
255            StrtodChar("1234567890123456789012345", 108));
256   CHECK_EQ(1234567890123456789012345e109,
257            StrtodChar("1234567890123456789012345", 109));
258   CHECK_EQ(1234567890123456789012345e110,
259            StrtodChar("1234567890123456789012345", 110));
260   CHECK_EQ(1234567890123456789012345e111,
261            StrtodChar("1234567890123456789012345", 111));
262   CHECK_EQ(1234567890123456789012345e112,
263            StrtodChar("1234567890123456789012345", 112));
264   CHECK_EQ(1234567890123456789012345e113,
265            StrtodChar("1234567890123456789012345", 113));
266   CHECK_EQ(1234567890123456789012345e114,
267            StrtodChar("1234567890123456789012345", 114));
268   CHECK_EQ(1234567890123456789012345e115,
269            StrtodChar("1234567890123456789012345", 115));
270 
271   CHECK_EQ(1234567890123456789052345e108,
272            StrtodChar("1234567890123456789052345", 108));
273   CHECK_EQ(1234567890123456789052345e109,
274            StrtodChar("1234567890123456789052345", 109));
275   CHECK_EQ(1234567890123456789052345e110,
276            StrtodChar("1234567890123456789052345", 110));
277   CHECK_EQ(1234567890123456789052345e111,
278            StrtodChar("1234567890123456789052345", 111));
279   CHECK_EQ(1234567890123456789052345e112,
280            StrtodChar("1234567890123456789052345", 112));
281   CHECK_EQ(1234567890123456789052345e113,
282            StrtodChar("1234567890123456789052345", 113));
283   CHECK_EQ(1234567890123456789052345e114,
284            StrtodChar("1234567890123456789052345", 114));
285   CHECK_EQ(1234567890123456789052345e115,
286            StrtodChar("1234567890123456789052345", 115));
287 
288   CHECK_EQ(5.445618932859895e-255,
289            StrtodChar("5445618932859895362967233318697132813618813095743952975"
290                       "4392982234069699615600475529427176366709107287468930197"
291                       "8628345413991790019316974825934906752493984055268219809"
292                       "5012176093045431437495773903922425632551857520884625114"
293                       "6241265881735209066709685420744388526014389929047617597"
294                       "0302268848374508109029268898695825171158085457567481507"
295                       "4162979705098246243690189880319928315307816832576838178"
296                       "2563074014542859888710209237525873301724479666744537857"
297                       "9026553346649664045621387124193095870305991178772256504"
298                       "4368663670643970181259143319016472430928902201239474588"
299                       "1392338901353291306607057623202353588698746085415097902"
300                       "6640064319118728664842287477491068264828851624402189317"
301                       "2769161449825765517353755844373640588822904791244190695"
302                       "2998382932630754670573838138825217065450843010498555058"
303                       "88186560731", -1035));
304 
305   // Boundary cases. Boundaries themselves should round to even.
306   //
307   // 0x1FFFFFFFFFFFF * 2^3 = 72057594037927928
308   //                   next: 72057594037927936
309   //               boundary: 72057594037927932  should round up.
310   CHECK_EQ(72057594037927928.0, StrtodChar("72057594037927928", 0));
311   CHECK_EQ(72057594037927936.0, StrtodChar("72057594037927936", 0));
312   CHECK_EQ(72057594037927936.0, StrtodChar("72057594037927932", 0));
313   CHECK_EQ(72057594037927928.0, StrtodChar("7205759403792793199999", -5));
314   CHECK_EQ(72057594037927936.0, StrtodChar("7205759403792793200001", -5));
315 
316   // 0x1FFFFFFFFFFFF * 2^10 = 9223372036854774784
317   //                    next: 9223372036854775808
318   //                boundary: 9223372036854775296 should round up.
319   CHECK_EQ(9223372036854774784.0, StrtodChar("9223372036854774784", 0));
320   CHECK_EQ(9223372036854775808.0, StrtodChar("9223372036854775808", 0));
321   CHECK_EQ(9223372036854775808.0, StrtodChar("9223372036854775296", 0));
322   CHECK_EQ(9223372036854774784.0, StrtodChar("922337203685477529599999", -5));
323   CHECK_EQ(9223372036854775808.0, StrtodChar("922337203685477529600001", -5));
324 
325   // 0x1FFFFFFFFFFFF * 2^50 = 10141204801825834086073718800384
326   //                    next: 10141204801825835211973625643008
327   //                boundary: 10141204801825834649023672221696 should round up.
328   CHECK_EQ(10141204801825834086073718800384.0,
329            StrtodChar("10141204801825834086073718800384", 0));
330   CHECK_EQ(10141204801825835211973625643008.0,
331            StrtodChar("10141204801825835211973625643008", 0));
332   CHECK_EQ(10141204801825835211973625643008.0,
333            StrtodChar("10141204801825834649023672221696", 0));
334   CHECK_EQ(10141204801825834086073718800384.0,
335            StrtodChar("1014120480182583464902367222169599999", -5));
336   CHECK_EQ(10141204801825835211973625643008.0,
337            StrtodChar("1014120480182583464902367222169600001", -5));
338 
339   // 0x1FFFFFFFFFFFF * 2^99 = 5708990770823838890407843763683279797179383808
340   //                    next: 5708990770823839524233143877797980545530986496
341   //                boundary: 5708990770823839207320493820740630171355185152
342   // The boundary should round up.
343   CHECK_EQ(5708990770823838890407843763683279797179383808.0,
344            StrtodChar("5708990770823838890407843763683279797179383808", 0));
345   CHECK_EQ(5708990770823839524233143877797980545530986496.0,
346            StrtodChar("5708990770823839524233143877797980545530986496", 0));
347   CHECK_EQ(5708990770823839524233143877797980545530986496.0,
348            StrtodChar("5708990770823839207320493820740630171355185152", 0));
349   CHECK_EQ(5708990770823838890407843763683279797179383808.0,
350            StrtodChar("5708990770823839207320493820740630171355185151999", -3));
351   CHECK_EQ(5708990770823839524233143877797980545530986496.0,
352            StrtodChar("5708990770823839207320493820740630171355185152001", -3));
353 
354   // The following test-cases got some public attention in early 2011 when they
355   // sent Java and PHP into an infinite loop.
356   CHECK_EQ(2.225073858507201e-308, StrtodChar("22250738585072011", -324));
357   CHECK_EQ(2.22507385850720138309e-308,
358            StrtodChar("22250738585072011360574097967091319759348195463516456480"
359                       "23426109724822222021076945516529523908135087914149158913"
360                       "03962110687008643869459464552765720740782062174337998814"
361                       "10632673292535522868813721490129811224514518898490572223"
362                       "07285255133155755015914397476397983411801999323962548289"
363                       "01710708185069063066665599493827577257201576306269066333"
364                       "26475653000092458883164330377797918696120494973903778297"
365                       "04905051080609940730262937128958950003583799967207254304"
366                       "36028407889577179615094551674824347103070260914462157228"
367                       "98802581825451803257070188608721131280795122334262883686"
368                       "22321503775666622503982534335974568884423900265498198385"
369                       "48794829220689472168983109969836584681402285424333066033"
370                       "98508864458040010349339704275671864433837704860378616227"
371                       "71738545623065874679014086723327636718751", -1076));
372 }
373 
374 
CompareBignumToDiyFp(const Bignum & bignum_digits,int bignum_exponent,DiyFp diy_fp)375 static int CompareBignumToDiyFp(const Bignum& bignum_digits,
376                                 int bignum_exponent,
377                                 DiyFp diy_fp) {
378   Bignum bignum;
379   bignum.AssignBignum(bignum_digits);
380   Bignum other;
381   other.AssignUInt64(diy_fp.f());
382   if (bignum_exponent >= 0) {
383     bignum.MultiplyByPowerOfTen(bignum_exponent);
384   } else {
385     other.MultiplyByPowerOfTen(-bignum_exponent);
386   }
387   if (diy_fp.e() >= 0) {
388     other.ShiftLeft(diy_fp.e());
389   } else {
390     bignum.ShiftLeft(-diy_fp.e());
391   }
392   return Bignum::Compare(bignum, other);
393 }
394 
395 
CheckDouble(Vector<const char> buffer,int exponent,double to_check)396 static bool CheckDouble(Vector<const char> buffer,
397                         int exponent,
398                         double to_check) {
399   DiyFp lower_boundary;
400   DiyFp upper_boundary;
401   Bignum input_digits;
402   input_digits.AssignDecimalString(buffer);
403   if (to_check == 0.0) {
404     const double kMinDouble = 4e-324;
405     // Check that the buffer*10^exponent < (0 + kMinDouble)/2.
406     Double d(kMinDouble);
407     d.NormalizedBoundaries(&lower_boundary, &upper_boundary);
408     return CompareBignumToDiyFp(input_digits, exponent, lower_boundary) <= 0;
409   }
410   if (to_check == V8_INFINITY) {
411     const double kMaxDouble = 1.7976931348623157e308;
412     // Check that the buffer*10^exponent >= boundary between kMaxDouble and inf.
413     Double d(kMaxDouble);
414     d.NormalizedBoundaries(&lower_boundary, &upper_boundary);
415     return CompareBignumToDiyFp(input_digits, exponent, upper_boundary) >= 0;
416   }
417   Double d(to_check);
418   d.NormalizedBoundaries(&lower_boundary, &upper_boundary);
419   if ((d.Significand() & 1) == 0) {
420     return CompareBignumToDiyFp(input_digits, exponent, lower_boundary) >= 0 &&
421         CompareBignumToDiyFp(input_digits, exponent, upper_boundary) <= 0;
422   } else {
423     return CompareBignumToDiyFp(input_digits, exponent, lower_boundary) > 0 &&
424         CompareBignumToDiyFp(input_digits, exponent, upper_boundary) < 0;
425   }
426 }
427 
428 
429 // Copied from v8.cc and adapted to make the function deterministic.
DeterministicRandom()430 static uint32_t DeterministicRandom() {
431   // Random number generator using George Marsaglia's MWC algorithm.
432   static uint32_t hi = 0;
433   static uint32_t lo = 0;
434 
435   // Initialization values don't have any special meaning. (They are the result
436   // of two calls to rand().)
437   if (hi == 0) hi = 0xbfe166e7;
438   if (lo == 0) lo = 0x64d1c3c9;
439 
440   // Mix the bits.
441   hi = 36969 * (hi & 0xFFFF) + (hi >> 16);
442   lo = 18273 * (lo & 0xFFFF) + (lo >> 16);
443   return (hi << 16) + (lo & 0xFFFF);
444 }
445 
446 
447 static const int kBufferSize = 1024;
448 static const int kShortStrtodRandomCount = 2;
449 static const int kLargeStrtodRandomCount = 2;
450 
TEST(RandomStrtod)451 TEST(RandomStrtod) {
452   v8::base::RandomNumberGenerator rng;
453   char buffer[kBufferSize];
454   for (int length = 1; length < 15; length++) {
455     for (int i = 0; i < kShortStrtodRandomCount; ++i) {
456       int pos = 0;
457       for (int j = 0; j < length; ++j) {
458         buffer[pos++] = rng.NextInt(10) + '0';
459       }
460       int exponent = DeterministicRandom() % (25*2 + 1) - 25 - length;
461       buffer[pos] = '\0';
462       Vector<const char> vector(buffer, pos);
463       double strtod_result = Strtod(vector, exponent);
464       CHECK(CheckDouble(vector, exponent, strtod_result));
465     }
466   }
467   for (int length = 15; length < 800; length += 2) {
468     for (int i = 0; i < kLargeStrtodRandomCount; ++i) {
469       int pos = 0;
470       for (int j = 0; j < length; ++j) {
471         buffer[pos++] = rng.NextInt(10) + '0';
472       }
473       int exponent = DeterministicRandom() % (308*2 + 1) - 308 - length;
474       buffer[pos] = '\0';
475       Vector<const char> vector(buffer, pos);
476       double strtod_result = Strtod(vector, exponent);
477       CHECK(CheckDouble(vector, exponent, strtod_result));
478     }
479   }
480 }
481