v8/test/cctest/test-strtod.cc

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// Copyright 2006-2008 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include <stdlib.h>
#include "v8.h"
#include "bignum.h"
#include "cctest.h"
#include "diy-fp.h"
#include "double.h"
#include "strtod.h"
using namespace v8::internal;
static Vector<const char> StringToVector(const char* str) {
return Vector<const char>(str, StrLength(str));
}
static double StrtodChar(const char* str, int exponent) {
return Strtod(StringToVector(str), exponent);
}
TEST(Strtod) {
Vector<const char> vector;
vector = StringToVector("0");
CHECK_EQ(0.0, Strtod(vector, 1));
CHECK_EQ(0.0, Strtod(vector, 2));
CHECK_EQ(0.0, Strtod(vector, -2));
CHECK_EQ(0.0, Strtod(vector, -999));
CHECK_EQ(0.0, Strtod(vector, +999));
vector = StringToVector("1");
CHECK_EQ(1.0, Strtod(vector, 0));
CHECK_EQ(10.0, Strtod(vector, 1));
CHECK_EQ(100.0, Strtod(vector, 2));
CHECK_EQ(1e20, Strtod(vector, 20));
CHECK_EQ(1e22, Strtod(vector, 22));
CHECK_EQ(1e23, Strtod(vector, 23));
CHECK_EQ(1e35, Strtod(vector, 35));
CHECK_EQ(1e36, Strtod(vector, 36));
CHECK_EQ(1e37, Strtod(vector, 37));
CHECK_EQ(1e-1, Strtod(vector, -1));
CHECK_EQ(1e-2, Strtod(vector, -2));
CHECK_EQ(1e-5, Strtod(vector, -5));
CHECK_EQ(1e-20, Strtod(vector, -20));
CHECK_EQ(1e-22, Strtod(vector, -22));
CHECK_EQ(1e-23, Strtod(vector, -23));
CHECK_EQ(1e-25, Strtod(vector, -25));
CHECK_EQ(1e-39, Strtod(vector, -39));
vector = StringToVector("2");
CHECK_EQ(2.0, Strtod(vector, 0));
CHECK_EQ(20.0, Strtod(vector, 1));
CHECK_EQ(200.0, Strtod(vector, 2));
CHECK_EQ(2e20, Strtod(vector, 20));
CHECK_EQ(2e22, Strtod(vector, 22));
CHECK_EQ(2e23, Strtod(vector, 23));
CHECK_EQ(2e35, Strtod(vector, 35));
CHECK_EQ(2e36, Strtod(vector, 36));
CHECK_EQ(2e37, Strtod(vector, 37));
CHECK_EQ(2e-1, Strtod(vector, -1));
CHECK_EQ(2e-2, Strtod(vector, -2));
CHECK_EQ(2e-5, Strtod(vector, -5));
CHECK_EQ(2e-20, Strtod(vector, -20));
CHECK_EQ(2e-22, Strtod(vector, -22));
CHECK_EQ(2e-23, Strtod(vector, -23));
CHECK_EQ(2e-25, Strtod(vector, -25));
CHECK_EQ(2e-39, Strtod(vector, -39));
vector = StringToVector("9");
CHECK_EQ(9.0, Strtod(vector, 0));
CHECK_EQ(90.0, Strtod(vector, 1));
CHECK_EQ(900.0, Strtod(vector, 2));
CHECK_EQ(9e20, Strtod(vector, 20));
CHECK_EQ(9e22, Strtod(vector, 22));
CHECK_EQ(9e23, Strtod(vector, 23));
CHECK_EQ(9e35, Strtod(vector, 35));
CHECK_EQ(9e36, Strtod(vector, 36));
CHECK_EQ(9e37, Strtod(vector, 37));
CHECK_EQ(9e-1, Strtod(vector, -1));
CHECK_EQ(9e-2, Strtod(vector, -2));
CHECK_EQ(9e-5, Strtod(vector, -5));
CHECK_EQ(9e-20, Strtod(vector, -20));
CHECK_EQ(9e-22, Strtod(vector, -22));
CHECK_EQ(9e-23, Strtod(vector, -23));
CHECK_EQ(9e-25, Strtod(vector, -25));
CHECK_EQ(9e-39, Strtod(vector, -39));
vector = StringToVector("12345");
CHECK_EQ(12345.0, Strtod(vector, 0));
CHECK_EQ(123450.0, Strtod(vector, 1));
CHECK_EQ(1234500.0, Strtod(vector, 2));
CHECK_EQ(12345e20, Strtod(vector, 20));
CHECK_EQ(12345e22, Strtod(vector, 22));
CHECK_EQ(12345e23, Strtod(vector, 23));
CHECK_EQ(12345e30, Strtod(vector, 30));
CHECK_EQ(12345e31, Strtod(vector, 31));
CHECK_EQ(12345e32, Strtod(vector, 32));
CHECK_EQ(12345e35, Strtod(vector, 35));
CHECK_EQ(12345e36, Strtod(vector, 36));
CHECK_EQ(12345e37, Strtod(vector, 37));
CHECK_EQ(12345e-1, Strtod(vector, -1));
CHECK_EQ(12345e-2, Strtod(vector, -2));
CHECK_EQ(12345e-5, Strtod(vector, -5));
CHECK_EQ(12345e-20, Strtod(vector, -20));
CHECK_EQ(12345e-22, Strtod(vector, -22));
CHECK_EQ(12345e-23, Strtod(vector, -23));
CHECK_EQ(12345e-25, Strtod(vector, -25));
CHECK_EQ(12345e-39, Strtod(vector, -39));
vector = StringToVector("12345678901234");
CHECK_EQ(12345678901234.0, Strtod(vector, 0));
CHECK_EQ(123456789012340.0, Strtod(vector, 1));
CHECK_EQ(1234567890123400.0, Strtod(vector, 2));
CHECK_EQ(12345678901234e20, Strtod(vector, 20));
CHECK_EQ(12345678901234e22, Strtod(vector, 22));
CHECK_EQ(12345678901234e23, Strtod(vector, 23));
CHECK_EQ(12345678901234e30, Strtod(vector, 30));
CHECK_EQ(12345678901234e31, Strtod(vector, 31));
CHECK_EQ(12345678901234e32, Strtod(vector, 32));
CHECK_EQ(12345678901234e35, Strtod(vector, 35));
CHECK_EQ(12345678901234e36, Strtod(vector, 36));
CHECK_EQ(12345678901234e37, Strtod(vector, 37));
CHECK_EQ(12345678901234e-1, Strtod(vector, -1));
CHECK_EQ(12345678901234e-2, Strtod(vector, -2));
CHECK_EQ(12345678901234e-5, Strtod(vector, -5));
CHECK_EQ(12345678901234e-20, Strtod(vector, -20));
CHECK_EQ(12345678901234e-22, Strtod(vector, -22));
CHECK_EQ(12345678901234e-23, Strtod(vector, -23));
CHECK_EQ(12345678901234e-25, Strtod(vector, -25));
CHECK_EQ(12345678901234e-39, Strtod(vector, -39));
vector = StringToVector("123456789012345");
CHECK_EQ(123456789012345.0, Strtod(vector, 0));
CHECK_EQ(1234567890123450.0, Strtod(vector, 1));
CHECK_EQ(12345678901234500.0, Strtod(vector, 2));
CHECK_EQ(123456789012345e20, Strtod(vector, 20));
CHECK_EQ(123456789012345e22, Strtod(vector, 22));
CHECK_EQ(123456789012345e23, Strtod(vector, 23));
CHECK_EQ(123456789012345e35, Strtod(vector, 35));
CHECK_EQ(123456789012345e36, Strtod(vector, 36));
CHECK_EQ(123456789012345e37, Strtod(vector, 37));
CHECK_EQ(123456789012345e39, Strtod(vector, 39));
CHECK_EQ(123456789012345e-1, Strtod(vector, -1));
CHECK_EQ(123456789012345e-2, Strtod(vector, -2));
CHECK_EQ(123456789012345e-5, Strtod(vector, -5));
CHECK_EQ(123456789012345e-20, Strtod(vector, -20));
CHECK_EQ(123456789012345e-22, Strtod(vector, -22));
CHECK_EQ(123456789012345e-23, Strtod(vector, -23));
CHECK_EQ(123456789012345e-25, Strtod(vector, -25));
CHECK_EQ(123456789012345e-39, Strtod(vector, -39));
CHECK_EQ(0.0, StrtodChar("0", 12345));
CHECK_EQ(0.0, StrtodChar("", 1324));
CHECK_EQ(0.0, StrtodChar("000000000", 123));
CHECK_EQ(0.0, StrtodChar("2", -324));
CHECK_EQ(4e-324, StrtodChar("3", -324));
// It would be more readable to put non-zero literals on the left side (i.e.
// CHECK_EQ(1e-325, StrtodChar("1", -325))), but then Gcc complains that
// they are truncated to zero.
CHECK_EQ(0.0, StrtodChar("1", -325));
CHECK_EQ(0.0, StrtodChar("1", -325));
CHECK_EQ(0.0, StrtodChar("20000", -328));
CHECK_EQ(40000e-328, StrtodChar("30000", -328));
CHECK_EQ(0.0, StrtodChar("10000", -329));
CHECK_EQ(0.0, StrtodChar("90000", -329));
CHECK_EQ(0.0, StrtodChar("000000001", -325));
CHECK_EQ(0.0, StrtodChar("000000001", -325));
CHECK_EQ(0.0, StrtodChar("0000000020000", -328));
CHECK_EQ(40000e-328, StrtodChar("00000030000", -328));
CHECK_EQ(0.0, StrtodChar("0000000010000", -329));
CHECK_EQ(0.0, StrtodChar("0000000090000", -329));
// It would be more readable to put the literals (and not V8_INFINITY) on the
// left side (i.e. CHECK_EQ(1e309, StrtodChar("1", 309))), but then Gcc
// complains that the floating constant exceeds range of 'double'.
CHECK_EQ(V8_INFINITY, StrtodChar("1", 309));
CHECK_EQ(1e308, StrtodChar("1", 308));
CHECK_EQ(1234e305, StrtodChar("1234", 305));
CHECK_EQ(1234e304, StrtodChar("1234", 304));
CHECK_EQ(V8_INFINITY, StrtodChar("18", 307));
CHECK_EQ(17e307, StrtodChar("17", 307));
CHECK_EQ(V8_INFINITY, StrtodChar("0000001", 309));
CHECK_EQ(1e308, StrtodChar("00000001", 308));
CHECK_EQ(1234e305, StrtodChar("00000001234", 305));
CHECK_EQ(1234e304, StrtodChar("000000001234", 304));
CHECK_EQ(V8_INFINITY, StrtodChar("0000000018", 307));
CHECK_EQ(17e307, StrtodChar("0000000017", 307));
CHECK_EQ(V8_INFINITY, StrtodChar("1000000", 303));
CHECK_EQ(1e308, StrtodChar("100000", 303));
CHECK_EQ(1234e305, StrtodChar("123400000", 300));
CHECK_EQ(1234e304, StrtodChar("123400000", 299));
CHECK_EQ(V8_INFINITY, StrtodChar("180000000", 300));
CHECK_EQ(17e307, StrtodChar("170000000", 300));
CHECK_EQ(V8_INFINITY, StrtodChar("00000001000000", 303));
CHECK_EQ(1e308, StrtodChar("000000000000100000", 303));
CHECK_EQ(1234e305, StrtodChar("00000000123400000", 300));
CHECK_EQ(1234e304, StrtodChar("0000000123400000", 299));
CHECK_EQ(V8_INFINITY, StrtodChar("00000000180000000", 300));
CHECK_EQ(17e307, StrtodChar("00000000170000000", 300));
CHECK_EQ(1.7976931348623157E+308, StrtodChar("17976931348623157", 292));
CHECK_EQ(1.7976931348623158E+308, StrtodChar("17976931348623158", 292));
CHECK_EQ(V8_INFINITY, StrtodChar("17976931348623159", 292));
// The following number is the result of 89255.0/1e22. Both floating-point
// numbers can be accurately represented with doubles. However on Linux,x86
// the floating-point stack is set to 80bits and the double-rounding
// introduces an error.
CHECK_EQ(89255e-22, StrtodChar("89255", -22));
// Some random values.
CHECK_EQ(358416272e-33, StrtodChar("358416272", -33));
CHECK_EQ(104110013277974872254e-225,
StrtodChar("104110013277974872254", -225));
CHECK_EQ(123456789e108, StrtodChar("123456789", 108));
CHECK_EQ(123456789e109, StrtodChar("123456789", 109));
CHECK_EQ(123456789e110, StrtodChar("123456789", 110));
CHECK_EQ(123456789e111, StrtodChar("123456789", 111));
CHECK_EQ(123456789e112, StrtodChar("123456789", 112));
CHECK_EQ(123456789e113, StrtodChar("123456789", 113));
CHECK_EQ(123456789e114, StrtodChar("123456789", 114));
CHECK_EQ(123456789e115, StrtodChar("123456789", 115));
CHECK_EQ(1234567890123456789012345e108,
StrtodChar("1234567890123456789012345", 108));
CHECK_EQ(1234567890123456789012345e109,
StrtodChar("1234567890123456789012345", 109));
CHECK_EQ(1234567890123456789012345e110,
StrtodChar("1234567890123456789012345", 110));
CHECK_EQ(1234567890123456789012345e111,
StrtodChar("1234567890123456789012345", 111));
CHECK_EQ(1234567890123456789012345e112,
StrtodChar("1234567890123456789012345", 112));
CHECK_EQ(1234567890123456789012345e113,
StrtodChar("1234567890123456789012345", 113));
CHECK_EQ(1234567890123456789012345e114,
StrtodChar("1234567890123456789012345", 114));
CHECK_EQ(1234567890123456789012345e115,
StrtodChar("1234567890123456789012345", 115));
CHECK_EQ(1234567890123456789052345e108,
StrtodChar("1234567890123456789052345", 108));
CHECK_EQ(1234567890123456789052345e109,
StrtodChar("1234567890123456789052345", 109));
CHECK_EQ(1234567890123456789052345e110,
StrtodChar("1234567890123456789052345", 110));
CHECK_EQ(1234567890123456789052345e111,
StrtodChar("1234567890123456789052345", 111));
CHECK_EQ(1234567890123456789052345e112,
StrtodChar("1234567890123456789052345", 112));
CHECK_EQ(1234567890123456789052345e113,
StrtodChar("1234567890123456789052345", 113));
CHECK_EQ(1234567890123456789052345e114,
StrtodChar("1234567890123456789052345", 114));
CHECK_EQ(1234567890123456789052345e115,
StrtodChar("1234567890123456789052345", 115));
CHECK_EQ(5.445618932859895e-255,
StrtodChar("5445618932859895362967233318697132813618813095743952975"
"4392982234069699615600475529427176366709107287468930197"
"8628345413991790019316974825934906752493984055268219809"
"5012176093045431437495773903922425632551857520884625114"
"6241265881735209066709685420744388526014389929047617597"
"0302268848374508109029268898695825171158085457567481507"
"4162979705098246243690189880319928315307816832576838178"
"2563074014542859888710209237525873301724479666744537857"
"9026553346649664045621387124193095870305991178772256504"
"4368663670643970181259143319016472430928902201239474588"
"1392338901353291306607057623202353588698746085415097902"
"6640064319118728664842287477491068264828851624402189317"
"2769161449825765517353755844373640588822904791244190695"
"2998382932630754670573838138825217065450843010498555058"
"88186560731", -1035));
// Boundary cases. Boundaries themselves should round to even.
//
// 0x1FFFFFFFFFFFF * 2^3 = 72057594037927928
// next: 72057594037927936
// boundary: 72057594037927932 should round up.
CHECK_EQ(72057594037927928.0, StrtodChar("72057594037927928", 0));
CHECK_EQ(72057594037927936.0, StrtodChar("72057594037927936", 0));
CHECK_EQ(72057594037927936.0, StrtodChar("72057594037927932", 0));
CHECK_EQ(72057594037927928.0, StrtodChar("7205759403792793199999", -5));
CHECK_EQ(72057594037927936.0, StrtodChar("7205759403792793200001", -5));
// 0x1FFFFFFFFFFFF * 2^10 = 9223372036854774784
// next: 9223372036854775808
// boundary: 9223372036854775296 should round up.
CHECK_EQ(9223372036854774784.0, StrtodChar("9223372036854774784", 0));
CHECK_EQ(9223372036854775808.0, StrtodChar("9223372036854775808", 0));
CHECK_EQ(9223372036854775808.0, StrtodChar("9223372036854775296", 0));
CHECK_EQ(9223372036854774784.0, StrtodChar("922337203685477529599999", -5));
CHECK_EQ(9223372036854775808.0, StrtodChar("922337203685477529600001", -5));
// 0x1FFFFFFFFFFFF * 2^50 = 10141204801825834086073718800384
// next: 10141204801825835211973625643008
// boundary: 10141204801825834649023672221696 should round up.
CHECK_EQ(10141204801825834086073718800384.0,
StrtodChar("10141204801825834086073718800384", 0));
CHECK_EQ(10141204801825835211973625643008.0,
StrtodChar("10141204801825835211973625643008", 0));
CHECK_EQ(10141204801825835211973625643008.0,
StrtodChar("10141204801825834649023672221696", 0));
CHECK_EQ(10141204801825834086073718800384.0,
StrtodChar("1014120480182583464902367222169599999", -5));
CHECK_EQ(10141204801825835211973625643008.0,
StrtodChar("1014120480182583464902367222169600001", -5));
// 0x1FFFFFFFFFFFF * 2^99 = 5708990770823838890407843763683279797179383808
// next: 5708990770823839524233143877797980545530986496
// boundary: 5708990770823839207320493820740630171355185152
// The boundary should round up.
CHECK_EQ(5708990770823838890407843763683279797179383808.0,
StrtodChar("5708990770823838890407843763683279797179383808", 0));
CHECK_EQ(5708990770823839524233143877797980545530986496.0,
StrtodChar("5708990770823839524233143877797980545530986496", 0));
CHECK_EQ(5708990770823839524233143877797980545530986496.0,
StrtodChar("5708990770823839207320493820740630171355185152", 0));
CHECK_EQ(5708990770823838890407843763683279797179383808.0,
StrtodChar("5708990770823839207320493820740630171355185151999", -3));
CHECK_EQ(5708990770823839524233143877797980545530986496.0,
StrtodChar("5708990770823839207320493820740630171355185152001", -3));
// The following test-cases got some public attention in early 2011 when they
// sent Java and PHP into an infinite loop.
CHECK_EQ(2.225073858507201e-308, StrtodChar("22250738585072011", -324));
CHECK_EQ(2.22507385850720138309e-308,
StrtodChar("22250738585072011360574097967091319759348195463516456480"
"23426109724822222021076945516529523908135087914149158913"
"03962110687008643869459464552765720740782062174337998814"
"10632673292535522868813721490129811224514518898490572223"
"07285255133155755015914397476397983411801999323962548289"
"01710708185069063066665599493827577257201576306269066333"
"26475653000092458883164330377797918696120494973903778297"
"04905051080609940730262937128958950003583799967207254304"
"36028407889577179615094551674824347103070260914462157228"
"98802581825451803257070188608721131280795122334262883686"
"22321503775666622503982534335974568884423900265498198385"
"48794829220689472168983109969836584681402285424333066033"
"98508864458040010349339704275671864433837704860378616227"
"71738545623065874679014086723327636718751", -1076));
}
static int CompareBignumToDiyFp(const Bignum& bignum_digits,
int bignum_exponent,
DiyFp diy_fp) {
Bignum bignum;
bignum.AssignBignum(bignum_digits);
Bignum other;
other.AssignUInt64(diy_fp.f());
if (bignum_exponent >= 0) {
bignum.MultiplyByPowerOfTen(bignum_exponent);
} else {
other.MultiplyByPowerOfTen(-bignum_exponent);
}
if (diy_fp.e() >= 0) {
other.ShiftLeft(diy_fp.e());
} else {
bignum.ShiftLeft(-diy_fp.e());
}
return Bignum::Compare(bignum, other);
}
static bool CheckDouble(Vector<const char> buffer,
int exponent,
double to_check) {
DiyFp lower_boundary;
DiyFp upper_boundary;
Bignum input_digits;
input_digits.AssignDecimalString(buffer);
if (to_check == 0.0) {
const double kMinDouble = 4e-324;
// Check that the buffer*10^exponent < (0 + kMinDouble)/2.
Double d(kMinDouble);
d.NormalizedBoundaries(&lower_boundary, &upper_boundary);
return CompareBignumToDiyFp(input_digits, exponent, lower_boundary) <= 0;
}
if (to_check == V8_INFINITY) {
const double kMaxDouble = 1.7976931348623157e308;
// Check that the buffer*10^exponent >= boundary between kMaxDouble and inf.
Double d(kMaxDouble);
d.NormalizedBoundaries(&lower_boundary, &upper_boundary);
return CompareBignumToDiyFp(input_digits, exponent, upper_boundary) >= 0;
}
Double d(to_check);
d.NormalizedBoundaries(&lower_boundary, &upper_boundary);
if ((d.Significand() & 1) == 0) {
return CompareBignumToDiyFp(input_digits, exponent, lower_boundary) >= 0 &&
CompareBignumToDiyFp(input_digits, exponent, upper_boundary) <= 0;
} else {
return CompareBignumToDiyFp(input_digits, exponent, lower_boundary) > 0 &&
CompareBignumToDiyFp(input_digits, exponent, upper_boundary) < 0;
}
}
// Copied from v8.cc and adapted to make the function deterministic.
static uint32_t DeterministicRandom() {
// Random number generator using George Marsaglia's MWC algorithm.
static uint32_t hi = 0;
static uint32_t lo = 0;
// Initialization values don't have any special meaning. (They are the result
// of two calls to rand().)
if (hi == 0) hi = 0xbfe166e7;
if (lo == 0) lo = 0x64d1c3c9;
// Mix the bits.
hi = 36969 * (hi & 0xFFFF) + (hi >> 16);
lo = 18273 * (lo & 0xFFFF) + (lo >> 16);
return (hi << 16) + (lo & 0xFFFF);
}
static const int kBufferSize = 1024;
static const int kShortStrtodRandomCount = 2;
static const int kLargeStrtodRandomCount = 2;
TEST(RandomStrtod) {
srand(static_cast<unsigned int>(time(NULL)));
char buffer[kBufferSize];
for (int length = 1; length < 15; length++) {
for (int i = 0; i < kShortStrtodRandomCount; ++i) {
int pos = 0;
for (int j = 0; j < length; ++j) {
buffer[pos++] = rand() % 10 + '0';
}
int exponent = DeterministicRandom() % (25*2 + 1) - 25 - length;
buffer[pos] = '\0';
Vector<const char> vector(buffer, pos);
double strtod_result = Strtod(vector, exponent);
CHECK(CheckDouble(vector, exponent, strtod_result));
}
}
for (int length = 15; length < 800; length += 2) {
for (int i = 0; i < kLargeStrtodRandomCount; ++i) {
int pos = 0;
for (int j = 0; j < length; ++j) {
buffer[pos++] = rand() % 10 + '0';
}
int exponent = DeterministicRandom() % (308*2 + 1) - 308 - length;
buffer[pos] = '\0';
Vector<const char> vector(buffer, pos);
double strtod_result = Strtod(vector, exponent);
CHECK(CheckDouble(vector, exponent, strtod_result));
}
}
}