v8/test/cctest/test-random.cc
bmeurer@chromium.org eb381b9444 Introduce a RandonNumberGenerator class. Refactor the random/private_random uses in Isolate/Context.
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
2013-09-10 11:13:55 +00:00

101 lines
4.0 KiB
C++

// Copyright 2012 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 "compiler.h"
#include "execution.h"
#include "isolate.h"
using namespace v8::internal;
void SetSeeds(Handle<ByteArray> seeds, uint32_t state0, uint32_t state1) {
for (int i = 0; i < 4; i++) {
seeds->set(i, static_cast<byte>(state0 >> (i * kBitsPerByte)));
seeds->set(i + 4, static_cast<byte>(state1 >> (i * kBitsPerByte)));
}
}
void TestSeeds(Handle<JSFunction> fun,
Handle<Context> context,
uint32_t state0,
uint32_t state1) {
bool has_pending_exception;
Handle<JSObject> global(context->global_object());
Handle<ByteArray> seeds(context->random_seed());
SetSeeds(seeds, state0, state1);
Handle<Object> value = Execution::Call(
context->GetIsolate(), fun, global, 0, NULL, &has_pending_exception);
CHECK(value->IsHeapNumber());
CHECK(fun->IsOptimized());
double crankshaft_value = HeapNumber::cast(*value)->value();
SetSeeds(seeds, state0, state1);
V8::FillHeapNumberWithRandom(*value, *context);
double runtime_value = HeapNumber::cast(*value)->value();
CHECK_EQ(runtime_value, crankshaft_value);
}
TEST(CrankshaftRandom) {
v8::V8::Initialize();
// Skip test if crankshaft is disabled.
if (!Isolate::Current()->use_crankshaft()) return;
v8::Isolate* v8_isolate = v8::Isolate::GetCurrent();
v8::HandleScope scope(v8_isolate);
v8::Context::Scope context_scope(v8::Context::New(v8_isolate));
i::Isolate* isolate = reinterpret_cast<i::Isolate*>(v8_isolate);
Handle<Context> context(isolate->context());
Handle<JSObject> global(context->global_object());
Handle<ByteArray> seeds(context->random_seed());
bool has_pending_exception;
CompileRun("function f() { return Math.random(); }");
Object* string = Isolate::Current()->factory()->InternalizeOneByteString(
STATIC_ASCII_VECTOR("f"))->ToObjectChecked();
MaybeObject* fun_object =
context->global_object()->GetProperty(String::cast(string));
Handle<JSFunction> fun(JSFunction::cast(fun_object->ToObjectChecked()));
// Optimize function.
Execution::Call(isolate, fun, global, 0, NULL, &has_pending_exception);
Execution::Call(isolate, fun, global, 0, NULL, &has_pending_exception);
if (!fun->IsOptimized()) fun->MarkForLazyRecompilation();
// Test with some random values.
TestSeeds(fun, context, 0xC0C0AFFE, 0x31415926);
TestSeeds(fun, context, 0x01020304, 0xFFFFFFFF);
TestSeeds(fun, context, 0x00000001, 0x00000001);
}