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1 // Copyright 2006-2008 the V8 project authors. All rights reserved.
2 
3 #include <stdlib.h>
4 
5 #include "v8.h"
6 
7 #include "bignum.h"
8 #include "cctest.h"
9 #include "diy-fp.h"
10 #include "double.h"
11 #include "strtod.h"
12 
13 using namespace v8::internal;
14 
StringToVector(const char * str)15 static Vector<const char> StringToVector(const char* str) {
16   return Vector<const char>(str, StrLength(str));
17 }
18 
19 
StrtodChar(const char * str,int exponent)20 static double StrtodChar(const char* str, int exponent) {
21   return Strtod(StringToVector(str), exponent);
22 }
23 
24 
TEST(Strtod)25 TEST(Strtod) {
26   Vector<const char> vector;
27 
28   vector = StringToVector("0");
29   CHECK_EQ(0.0, Strtod(vector, 1));
30   CHECK_EQ(0.0, Strtod(vector, 2));
31   CHECK_EQ(0.0, Strtod(vector, -2));
32   CHECK_EQ(0.0, Strtod(vector, -999));
33   CHECK_EQ(0.0, Strtod(vector, +999));
34 
35   vector = StringToVector("1");
36   CHECK_EQ(1.0, Strtod(vector, 0));
37   CHECK_EQ(10.0, Strtod(vector, 1));
38   CHECK_EQ(100.0, Strtod(vector, 2));
39   CHECK_EQ(1e20, Strtod(vector, 20));
40   CHECK_EQ(1e22, Strtod(vector, 22));
41   CHECK_EQ(1e23, Strtod(vector, 23));
42   CHECK_EQ(1e35, Strtod(vector, 35));
43   CHECK_EQ(1e36, Strtod(vector, 36));
44   CHECK_EQ(1e37, Strtod(vector, 37));
45   CHECK_EQ(1e-1, Strtod(vector, -1));
46   CHECK_EQ(1e-2, Strtod(vector, -2));
47   CHECK_EQ(1e-5, Strtod(vector, -5));
48   CHECK_EQ(1e-20, Strtod(vector, -20));
49   CHECK_EQ(1e-22, Strtod(vector, -22));
50   CHECK_EQ(1e-23, Strtod(vector, -23));
51   CHECK_EQ(1e-25, Strtod(vector, -25));
52   CHECK_EQ(1e-39, Strtod(vector, -39));
53 
54   vector = StringToVector("2");
55   CHECK_EQ(2.0, Strtod(vector, 0));
56   CHECK_EQ(20.0, Strtod(vector, 1));
57   CHECK_EQ(200.0, Strtod(vector, 2));
58   CHECK_EQ(2e20, Strtod(vector, 20));
59   CHECK_EQ(2e22, Strtod(vector, 22));
60   CHECK_EQ(2e23, Strtod(vector, 23));
61   CHECK_EQ(2e35, Strtod(vector, 35));
62   CHECK_EQ(2e36, Strtod(vector, 36));
63   CHECK_EQ(2e37, Strtod(vector, 37));
64   CHECK_EQ(2e-1, Strtod(vector, -1));
65   CHECK_EQ(2e-2, Strtod(vector, -2));
66   CHECK_EQ(2e-5, Strtod(vector, -5));
67   CHECK_EQ(2e-20, Strtod(vector, -20));
68   CHECK_EQ(2e-22, Strtod(vector, -22));
69   CHECK_EQ(2e-23, Strtod(vector, -23));
70   CHECK_EQ(2e-25, Strtod(vector, -25));
71   CHECK_EQ(2e-39, Strtod(vector, -39));
72 
73   vector = StringToVector("9");
74   CHECK_EQ(9.0, Strtod(vector, 0));
75   CHECK_EQ(90.0, Strtod(vector, 1));
76   CHECK_EQ(900.0, Strtod(vector, 2));
77   CHECK_EQ(9e20, Strtod(vector, 20));
78   CHECK_EQ(9e22, Strtod(vector, 22));
79   CHECK_EQ(9e23, Strtod(vector, 23));
80   CHECK_EQ(9e35, Strtod(vector, 35));
81   CHECK_EQ(9e36, Strtod(vector, 36));
82   CHECK_EQ(9e37, Strtod(vector, 37));
83   CHECK_EQ(9e-1, Strtod(vector, -1));
84   CHECK_EQ(9e-2, Strtod(vector, -2));
85   CHECK_EQ(9e-5, Strtod(vector, -5));
86   CHECK_EQ(9e-20, Strtod(vector, -20));
87   CHECK_EQ(9e-22, Strtod(vector, -22));
88   CHECK_EQ(9e-23, Strtod(vector, -23));
89   CHECK_EQ(9e-25, Strtod(vector, -25));
90   CHECK_EQ(9e-39, Strtod(vector, -39));
91 
92   vector = StringToVector("12345");
93   CHECK_EQ(12345.0, Strtod(vector, 0));
94   CHECK_EQ(123450.0, Strtod(vector, 1));
95   CHECK_EQ(1234500.0, Strtod(vector, 2));
96   CHECK_EQ(12345e20, Strtod(vector, 20));
97   CHECK_EQ(12345e22, Strtod(vector, 22));
98   CHECK_EQ(12345e23, Strtod(vector, 23));
99   CHECK_EQ(12345e30, Strtod(vector, 30));
100   CHECK_EQ(12345e31, Strtod(vector, 31));
101   CHECK_EQ(12345e32, Strtod(vector, 32));
102   CHECK_EQ(12345e35, Strtod(vector, 35));
103   CHECK_EQ(12345e36, Strtod(vector, 36));
104   CHECK_EQ(12345e37, Strtod(vector, 37));
105   CHECK_EQ(12345e-1, Strtod(vector, -1));
106   CHECK_EQ(12345e-2, Strtod(vector, -2));
107   CHECK_EQ(12345e-5, Strtod(vector, -5));
108   CHECK_EQ(12345e-20, Strtod(vector, -20));
109   CHECK_EQ(12345e-22, Strtod(vector, -22));
110   CHECK_EQ(12345e-23, Strtod(vector, -23));
111   CHECK_EQ(12345e-25, Strtod(vector, -25));
112   CHECK_EQ(12345e-39, Strtod(vector, -39));
113 
114   vector = StringToVector("12345678901234");
115   CHECK_EQ(12345678901234.0, Strtod(vector, 0));
116   CHECK_EQ(123456789012340.0, Strtod(vector, 1));
117   CHECK_EQ(1234567890123400.0, Strtod(vector, 2));
118   CHECK_EQ(12345678901234e20, Strtod(vector, 20));
119   CHECK_EQ(12345678901234e22, Strtod(vector, 22));
120   CHECK_EQ(12345678901234e23, Strtod(vector, 23));
121   CHECK_EQ(12345678901234e30, Strtod(vector, 30));
122   CHECK_EQ(12345678901234e31, Strtod(vector, 31));
123   CHECK_EQ(12345678901234e32, Strtod(vector, 32));
124   CHECK_EQ(12345678901234e35, Strtod(vector, 35));
125   CHECK_EQ(12345678901234e36, Strtod(vector, 36));
126   CHECK_EQ(12345678901234e37, Strtod(vector, 37));
127   CHECK_EQ(12345678901234e-1, Strtod(vector, -1));
128   CHECK_EQ(12345678901234e-2, Strtod(vector, -2));
129   CHECK_EQ(12345678901234e-5, Strtod(vector, -5));
130   CHECK_EQ(12345678901234e-20, Strtod(vector, -20));
131   CHECK_EQ(12345678901234e-22, Strtod(vector, -22));
132   CHECK_EQ(12345678901234e-23, Strtod(vector, -23));
133   CHECK_EQ(12345678901234e-25, Strtod(vector, -25));
134   CHECK_EQ(12345678901234e-39, Strtod(vector, -39));
135 
136   vector = StringToVector("123456789012345");
137   CHECK_EQ(123456789012345.0, Strtod(vector, 0));
138   CHECK_EQ(1234567890123450.0, Strtod(vector, 1));
139   CHECK_EQ(12345678901234500.0, Strtod(vector, 2));
140   CHECK_EQ(123456789012345e20, Strtod(vector, 20));
141   CHECK_EQ(123456789012345e22, Strtod(vector, 22));
142   CHECK_EQ(123456789012345e23, Strtod(vector, 23));
143   CHECK_EQ(123456789012345e35, Strtod(vector, 35));
144   CHECK_EQ(123456789012345e36, Strtod(vector, 36));
145   CHECK_EQ(123456789012345e37, Strtod(vector, 37));
146   CHECK_EQ(123456789012345e39, Strtod(vector, 39));
147   CHECK_EQ(123456789012345e-1, Strtod(vector, -1));
148   CHECK_EQ(123456789012345e-2, Strtod(vector, -2));
149   CHECK_EQ(123456789012345e-5, Strtod(vector, -5));
150   CHECK_EQ(123456789012345e-20, Strtod(vector, -20));
151   CHECK_EQ(123456789012345e-22, Strtod(vector, -22));
152   CHECK_EQ(123456789012345e-23, Strtod(vector, -23));
153   CHECK_EQ(123456789012345e-25, Strtod(vector, -25));
154   CHECK_EQ(123456789012345e-39, Strtod(vector, -39));
155 
156   CHECK_EQ(0.0, StrtodChar("0", 12345));
157   CHECK_EQ(0.0, StrtodChar("", 1324));
158   CHECK_EQ(0.0, StrtodChar("000000000", 123));
159   CHECK_EQ(0.0, StrtodChar("2", -324));
160   CHECK_EQ(4e-324, StrtodChar("3", -324));
161   // It would be more readable to put non-zero literals on the left side (i.e.
162   //   CHECK_EQ(1e-325, StrtodChar("1", -325))), but then Gcc complains that
163   // they are truncated to zero.
164   CHECK_EQ(0.0, StrtodChar("1", -325));
165   CHECK_EQ(0.0, StrtodChar("1", -325));
166   CHECK_EQ(0.0, StrtodChar("20000", -328));
167   CHECK_EQ(40000e-328, StrtodChar("30000", -328));
168   CHECK_EQ(0.0, StrtodChar("10000", -329));
169   CHECK_EQ(0.0, StrtodChar("90000", -329));
170   CHECK_EQ(0.0, StrtodChar("000000001", -325));
171   CHECK_EQ(0.0, StrtodChar("000000001", -325));
172   CHECK_EQ(0.0, StrtodChar("0000000020000", -328));
173   CHECK_EQ(40000e-328, StrtodChar("00000030000", -328));
174   CHECK_EQ(0.0, StrtodChar("0000000010000", -329));
175   CHECK_EQ(0.0, StrtodChar("0000000090000", -329));
176 
177   // It would be more readable to put the literals (and not V8_INFINITY) on the
178   // left side (i.e. CHECK_EQ(1e309, StrtodChar("1", 309))), but then Gcc
179   // complains that the floating constant exceeds range of 'double'.
180   CHECK_EQ(V8_INFINITY, StrtodChar("1", 309));
181   CHECK_EQ(1e308, StrtodChar("1", 308));
182   CHECK_EQ(1234e305, StrtodChar("1234", 305));
183   CHECK_EQ(1234e304, StrtodChar("1234", 304));
184   CHECK_EQ(V8_INFINITY, StrtodChar("18", 307));
185   CHECK_EQ(17e307, StrtodChar("17", 307));
186   CHECK_EQ(V8_INFINITY, StrtodChar("0000001", 309));
187   CHECK_EQ(1e308, StrtodChar("00000001", 308));
188   CHECK_EQ(1234e305, StrtodChar("00000001234", 305));
189   CHECK_EQ(1234e304, StrtodChar("000000001234", 304));
190   CHECK_EQ(V8_INFINITY, StrtodChar("0000000018", 307));
191   CHECK_EQ(17e307, StrtodChar("0000000017", 307));
192   CHECK_EQ(V8_INFINITY, StrtodChar("1000000", 303));
193   CHECK_EQ(1e308, StrtodChar("100000", 303));
194   CHECK_EQ(1234e305, StrtodChar("123400000", 300));
195   CHECK_EQ(1234e304, StrtodChar("123400000", 299));
196   CHECK_EQ(V8_INFINITY, StrtodChar("180000000", 300));
197   CHECK_EQ(17e307, StrtodChar("170000000", 300));
198   CHECK_EQ(V8_INFINITY, StrtodChar("00000001000000", 303));
199   CHECK_EQ(1e308, StrtodChar("000000000000100000", 303));
200   CHECK_EQ(1234e305, StrtodChar("00000000123400000", 300));
201   CHECK_EQ(1234e304, StrtodChar("0000000123400000", 299));
202   CHECK_EQ(V8_INFINITY, StrtodChar("00000000180000000", 300));
203   CHECK_EQ(17e307, StrtodChar("00000000170000000", 300));
204   CHECK_EQ(1.7976931348623157E+308, StrtodChar("17976931348623157", 292));
205   CHECK_EQ(1.7976931348623158E+308, StrtodChar("17976931348623158", 292));
206   CHECK_EQ(V8_INFINITY, StrtodChar("17976931348623159", 292));
207 
208   // The following number is the result of 89255.0/1e22. Both floating-point
209   // numbers can be accurately represented with doubles. However on Linux,x86
210   // the floating-point stack is set to 80bits and the double-rounding
211   // introduces an error.
212   CHECK_EQ(89255e-22, StrtodChar("89255", -22));
213 
214   // Some random values.
215   CHECK_EQ(358416272e-33, StrtodChar("358416272", -33));
216   CHECK_EQ(104110013277974872254e-225,
217            StrtodChar("104110013277974872254", -225));
218 
219   CHECK_EQ(123456789e108, StrtodChar("123456789", 108));
220   CHECK_EQ(123456789e109, StrtodChar("123456789", 109));
221   CHECK_EQ(123456789e110, StrtodChar("123456789", 110));
222   CHECK_EQ(123456789e111, StrtodChar("123456789", 111));
223   CHECK_EQ(123456789e112, StrtodChar("123456789", 112));
224   CHECK_EQ(123456789e113, StrtodChar("123456789", 113));
225   CHECK_EQ(123456789e114, StrtodChar("123456789", 114));
226   CHECK_EQ(123456789e115, StrtodChar("123456789", 115));
227 
228   CHECK_EQ(1234567890123456789012345e108,
229            StrtodChar("1234567890123456789012345", 108));
230   CHECK_EQ(1234567890123456789012345e109,
231            StrtodChar("1234567890123456789012345", 109));
232   CHECK_EQ(1234567890123456789012345e110,
233            StrtodChar("1234567890123456789012345", 110));
234   CHECK_EQ(1234567890123456789012345e111,
235            StrtodChar("1234567890123456789012345", 111));
236   CHECK_EQ(1234567890123456789012345e112,
237            StrtodChar("1234567890123456789012345", 112));
238   CHECK_EQ(1234567890123456789012345e113,
239            StrtodChar("1234567890123456789012345", 113));
240   CHECK_EQ(1234567890123456789012345e114,
241            StrtodChar("1234567890123456789012345", 114));
242   CHECK_EQ(1234567890123456789012345e115,
243            StrtodChar("1234567890123456789012345", 115));
244 
245   CHECK_EQ(1234567890123456789052345e108,
246            StrtodChar("1234567890123456789052345", 108));
247   CHECK_EQ(1234567890123456789052345e109,
248            StrtodChar("1234567890123456789052345", 109));
249   CHECK_EQ(1234567890123456789052345e110,
250            StrtodChar("1234567890123456789052345", 110));
251   CHECK_EQ(1234567890123456789052345e111,
252            StrtodChar("1234567890123456789052345", 111));
253   CHECK_EQ(1234567890123456789052345e112,
254            StrtodChar("1234567890123456789052345", 112));
255   CHECK_EQ(1234567890123456789052345e113,
256            StrtodChar("1234567890123456789052345", 113));
257   CHECK_EQ(1234567890123456789052345e114,
258            StrtodChar("1234567890123456789052345", 114));
259   CHECK_EQ(1234567890123456789052345e115,
260            StrtodChar("1234567890123456789052345", 115));
261 
262   CHECK_EQ(5.445618932859895e-255,
263            StrtodChar("5445618932859895362967233318697132813618813095743952975"
264                       "4392982234069699615600475529427176366709107287468930197"
265                       "8628345413991790019316974825934906752493984055268219809"
266                       "5012176093045431437495773903922425632551857520884625114"
267                       "6241265881735209066709685420744388526014389929047617597"
268                       "0302268848374508109029268898695825171158085457567481507"
269                       "4162979705098246243690189880319928315307816832576838178"
270                       "2563074014542859888710209237525873301724479666744537857"
271                       "9026553346649664045621387124193095870305991178772256504"
272                       "4368663670643970181259143319016472430928902201239474588"
273                       "1392338901353291306607057623202353588698746085415097902"
274                       "6640064319118728664842287477491068264828851624402189317"
275                       "2769161449825765517353755844373640588822904791244190695"
276                       "2998382932630754670573838138825217065450843010498555058"
277                       "88186560731", -1035));
278 
279   // Boundary cases. Boundaries themselves should round to even.
280   //
281   // 0x1FFFFFFFFFFFF * 2^3 = 72057594037927928
282   //                   next: 72057594037927936
283   //               boundary: 72057594037927932  should round up.
284   CHECK_EQ(72057594037927928.0, StrtodChar("72057594037927928", 0));
285   CHECK_EQ(72057594037927936.0, StrtodChar("72057594037927936", 0));
286   CHECK_EQ(72057594037927936.0, StrtodChar("72057594037927932", 0));
287   CHECK_EQ(72057594037927928.0, StrtodChar("7205759403792793199999", -5));
288   CHECK_EQ(72057594037927936.0, StrtodChar("7205759403792793200001", -5));
289 
290   // 0x1FFFFFFFFFFFF * 2^10 = 9223372036854774784
291   //                    next: 9223372036854775808
292   //                boundary: 9223372036854775296 should round up.
293   CHECK_EQ(9223372036854774784.0, StrtodChar("9223372036854774784", 0));
294   CHECK_EQ(9223372036854775808.0, StrtodChar("9223372036854775808", 0));
295   CHECK_EQ(9223372036854775808.0, StrtodChar("9223372036854775296", 0));
296   CHECK_EQ(9223372036854774784.0, StrtodChar("922337203685477529599999", -5));
297   CHECK_EQ(9223372036854775808.0, StrtodChar("922337203685477529600001", -5));
298 
299   // 0x1FFFFFFFFFFFF * 2^50 = 10141204801825834086073718800384
300   //                    next: 10141204801825835211973625643008
301   //                boundary: 10141204801825834649023672221696 should round up.
302   CHECK_EQ(10141204801825834086073718800384.0,
303            StrtodChar("10141204801825834086073718800384", 0));
304   CHECK_EQ(10141204801825835211973625643008.0,
305            StrtodChar("10141204801825835211973625643008", 0));
306   CHECK_EQ(10141204801825835211973625643008.0,
307            StrtodChar("10141204801825834649023672221696", 0));
308   CHECK_EQ(10141204801825834086073718800384.0,
309            StrtodChar("1014120480182583464902367222169599999", -5));
310   CHECK_EQ(10141204801825835211973625643008.0,
311            StrtodChar("1014120480182583464902367222169600001", -5));
312 
313   // 0x1FFFFFFFFFFFF * 2^99 = 5708990770823838890407843763683279797179383808
314   //                    next: 5708990770823839524233143877797980545530986496
315   //                boundary: 5708990770823839207320493820740630171355185152
316   // The boundary should round up.
317   CHECK_EQ(5708990770823838890407843763683279797179383808.0,
318            StrtodChar("5708990770823838890407843763683279797179383808", 0));
319   CHECK_EQ(5708990770823839524233143877797980545530986496.0,
320            StrtodChar("5708990770823839524233143877797980545530986496", 0));
321   CHECK_EQ(5708990770823839524233143877797980545530986496.0,
322            StrtodChar("5708990770823839207320493820740630171355185152", 0));
323   CHECK_EQ(5708990770823838890407843763683279797179383808.0,
324            StrtodChar("5708990770823839207320493820740630171355185151999", -3));
325   CHECK_EQ(5708990770823839524233143877797980545530986496.0,
326            StrtodChar("5708990770823839207320493820740630171355185152001", -3));
327 
328   // The following test-cases got some public attention in early 2011 when they
329   // sent Java and PHP into an infinite loop.
330   CHECK_EQ(2.225073858507201e-308, StrtodChar("22250738585072011", -324));
331   CHECK_EQ(2.22507385850720138309e-308,
332            StrtodChar("22250738585072011360574097967091319759348195463516456480"
333                       "23426109724822222021076945516529523908135087914149158913"
334                       "03962110687008643869459464552765720740782062174337998814"
335                       "10632673292535522868813721490129811224514518898490572223"
336                       "07285255133155755015914397476397983411801999323962548289"
337                       "01710708185069063066665599493827577257201576306269066333"
338                       "26475653000092458883164330377797918696120494973903778297"
339                       "04905051080609940730262937128958950003583799967207254304"
340                       "36028407889577179615094551674824347103070260914462157228"
341                       "98802581825451803257070188608721131280795122334262883686"
342                       "22321503775666622503982534335974568884423900265498198385"
343                       "48794829220689472168983109969836584681402285424333066033"
344                       "98508864458040010349339704275671864433837704860378616227"
345                       "71738545623065874679014086723327636718751", -1076));
346 }
347 
348 
CompareBignumToDiyFp(const Bignum & bignum_digits,int bignum_exponent,DiyFp diy_fp)349 static int CompareBignumToDiyFp(const Bignum& bignum_digits,
350                                 int bignum_exponent,
351                                 DiyFp diy_fp) {
352   Bignum bignum;
353   bignum.AssignBignum(bignum_digits);
354   Bignum other;
355   other.AssignUInt64(diy_fp.f());
356   if (bignum_exponent >= 0) {
357     bignum.MultiplyByPowerOfTen(bignum_exponent);
358   } else {
359     other.MultiplyByPowerOfTen(-bignum_exponent);
360   }
361   if (diy_fp.e() >= 0) {
362     other.ShiftLeft(diy_fp.e());
363   } else {
364     bignum.ShiftLeft(-diy_fp.e());
365   }
366   return Bignum::Compare(bignum, other);
367 }
368 
369 
CheckDouble(Vector<const char> buffer,int exponent,double to_check)370 static bool CheckDouble(Vector<const char> buffer,
371                         int exponent,
372                         double to_check) {
373   DiyFp lower_boundary;
374   DiyFp upper_boundary;
375   Bignum input_digits;
376   input_digits.AssignDecimalString(buffer);
377   if (to_check == 0.0) {
378     const double kMinDouble = 4e-324;
379     // Check that the buffer*10^exponent < (0 + kMinDouble)/2.
380     Double d(kMinDouble);
381     d.NormalizedBoundaries(&lower_boundary, &upper_boundary);
382     return CompareBignumToDiyFp(input_digits, exponent, lower_boundary) <= 0;
383   }
384   if (to_check == V8_INFINITY) {
385     const double kMaxDouble = 1.7976931348623157e308;
386     // Check that the buffer*10^exponent >= boundary between kMaxDouble and inf.
387     Double d(kMaxDouble);
388     d.NormalizedBoundaries(&lower_boundary, &upper_boundary);
389     return CompareBignumToDiyFp(input_digits, exponent, upper_boundary) >= 0;
390   }
391   Double d(to_check);
392   d.NormalizedBoundaries(&lower_boundary, &upper_boundary);
393   if ((d.Significand() & 1) == 0) {
394     return CompareBignumToDiyFp(input_digits, exponent, lower_boundary) >= 0 &&
395         CompareBignumToDiyFp(input_digits, exponent, upper_boundary) <= 0;
396   } else {
397     return CompareBignumToDiyFp(input_digits, exponent, lower_boundary) > 0 &&
398         CompareBignumToDiyFp(input_digits, exponent, upper_boundary) < 0;
399   }
400 }
401 
402 
403 // Copied from v8.cc and adapted to make the function deterministic.
DeterministicRandom()404 static uint32_t DeterministicRandom() {
405   // Random number generator using George Marsaglia's MWC algorithm.
406   static uint32_t hi = 0;
407   static uint32_t lo = 0;
408 
409   // Initialization values don't have any special meaning. (They are the result
410   // of two calls to random().)
411   if (hi == 0) hi = 0xbfe166e7;
412   if (lo == 0) lo = 0x64d1c3c9;
413 
414   // Mix the bits.
415   hi = 36969 * (hi & 0xFFFF) + (hi >> 16);
416   lo = 18273 * (lo & 0xFFFF) + (lo >> 16);
417   return (hi << 16) + (lo & 0xFFFF);
418 }
419 
420 
421 static const int kBufferSize = 1024;
422 static const int kShortStrtodRandomCount = 2;
423 static const int kLargeStrtodRandomCount = 2;
424 
TEST(RandomStrtod)425 TEST(RandomStrtod) {
426   char buffer[kBufferSize];
427   for (int length = 1; length < 15; length++) {
428     for (int i = 0; i < kShortStrtodRandomCount; ++i) {
429       int pos = 0;
430       for (int j = 0; j < length; ++j) {
431         buffer[pos++] = random() % 10 + '0';
432       }
433       int exponent = DeterministicRandom() % (25*2 + 1) - 25 - length;
434       buffer[pos] = '\0';
435       Vector<const char> vector(buffer, pos);
436       double strtod_result = Strtod(vector, exponent);
437       CHECK(CheckDouble(vector, exponent, strtod_result));
438     }
439   }
440   for (int length = 15; length < 800; length += 2) {
441     for (int i = 0; i < kLargeStrtodRandomCount; ++i) {
442       int pos = 0;
443       for (int j = 0; j < length; ++j) {
444         buffer[pos++] = random() % 10 + '0';
445       }
446       int exponent = DeterministicRandom() % (308*2 + 1) - 308 - length;
447       buffer[pos] = '\0';
448       Vector<const char> vector(buffer, pos);
449       double strtod_result = Strtod(vector, exponent);
450       CHECK(CheckDouble(vector, exponent, strtod_result));
451     }
452   }
453 }
454