eb381b9444
The RandomNumberGenerator is a pseudorandom number generator with 48-bit state. It is properly seeded using either (1) the --random-seed if specified, or (2) the entropy_source function if configured, or (3) /dev/urandom if available, or (4) falls back to Time and TimeTicks based seeding. Each Isolate now contains a RandomNumberGenerator, which replaces the previous private_random_seed. Every native context still has its own random_seed. But this random seed is now properly initialized during bootstrapping, instead of on-demand initialization. This will allow us to cleanup and speedup the HRandom implementation quite a lot (this is delayed for a followup CL)! Also stop messing with the system rand()/random(), which should not be done from a library anyway! We probably re-seeded the libc rand()/random() after the application (i.e. Chrome) already seeded it (with better entropy than what we used). Another followup CL will replace the use of the per-isolate random number generator for the address randomization and thereby get rid of the Isolate::UncheckedCurrent() usage in the platform code. TEST=cctest/test-random-number-generator,cctest/test-random R=mstarzinger@chromium.org Review URL: https://codereview.chromium.org/23548024 git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16612 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
93 lines
3.1 KiB
C++
93 lines
3.1 KiB
C++
// Copyright 2013 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 "v8.h"
|
|
|
|
#include "cctest.h"
|
|
#include "utils/random-number-generator.h"
|
|
|
|
using namespace v8::internal;
|
|
|
|
|
|
static const int kMaxRuns = 12345;
|
|
static const int kRandomSeeds[] = {
|
|
-1, 1, 42, 100, 1234567890, 987654321, 0xdeadbeef
|
|
};
|
|
|
|
|
|
TEST(NextIntWithMaxValue) {
|
|
for (unsigned n = 0; n < ARRAY_SIZE(kRandomSeeds); ++n) {
|
|
RandomNumberGenerator rng(kRandomSeeds[n]);
|
|
for (int max = 1; max <= kMaxRuns; ++max) {
|
|
int n = rng.NextInt(max);
|
|
CHECK_LE(0, n);
|
|
CHECK_LT(n, max);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
TEST(NextBoolReturnsBooleanValue) {
|
|
for (unsigned n = 0; n < ARRAY_SIZE(kRandomSeeds); ++n) {
|
|
RandomNumberGenerator rng(kRandomSeeds[n]);
|
|
for (int k = 0; k < kMaxRuns; ++k) {
|
|
bool b = rng.NextBool();
|
|
CHECK(b == false || b == true);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
TEST(NextDoubleRange) {
|
|
for (unsigned n = 0; n < ARRAY_SIZE(kRandomSeeds); ++n) {
|
|
RandomNumberGenerator rng(kRandomSeeds[n]);
|
|
for (int k = 0; k < kMaxRuns; ++k) {
|
|
double d = rng.NextDouble();
|
|
CHECK_LE(0.0, d);
|
|
CHECK_LT(d, 1.0);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
TEST(RandomSeedFlagIsUsed) {
|
|
for (unsigned n = 0; n < ARRAY_SIZE(kRandomSeeds); ++n) {
|
|
FLAG_random_seed = kRandomSeeds[n];
|
|
RandomNumberGenerator rng1;
|
|
RandomNumberGenerator rng2(kRandomSeeds[n]);
|
|
for (int k = 1; k <= kMaxRuns; ++k) {
|
|
int64_t i1, i2;
|
|
rng1.NextBytes(&i1, sizeof(i1));
|
|
rng2.NextBytes(&i2, sizeof(i2));
|
|
CHECK_EQ(i2, i1);
|
|
CHECK_EQ(rng2.NextInt(), rng1.NextInt());
|
|
CHECK_EQ(rng2.NextInt(k), rng1.NextInt(k));
|
|
CHECK_EQ(rng2.NextDouble(), rng1.NextDouble());
|
|
}
|
|
}
|
|
}
|