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// Copyright 2011 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 "isolate.h"
#include "bootstrapper.h"
#include "debug.h"
#include "deoptimizer.h"
#include "heap-profiler.h"
#include "hydrogen.h"
#include "lithium-allocator.h"
#include "log.h"
#include "runtime-profiler.h"
#include "serialize.h"
namespace v8 {
namespace internal {
static Mutex* init_once_mutex = OS::CreateMutex();
static bool init_once_called = false;
bool V8::is_running_ = false;
bool V8::has_been_setup_ = false;
bool V8::has_been_disposed_ = false;
bool V8::has_fatal_error_ = false;
bool V8::use_crankshaft_ = true;
bool V8::Initialize(Deserializer* des) {
InitializeOncePerProcess();
// The current thread may not yet had entered an isolate to run.
// Note the Isolate::Current() may be non-null because for various
// initialization purposes an initializing thread may be assigned an isolate
// but not actually enter it.
if (i::Isolate::CurrentPerIsolateThreadData() == NULL) {
i::Isolate::EnterDefaultIsolate();
}
ASSERT(i::Isolate::CurrentPerIsolateThreadData() != NULL);
ASSERT(i::Isolate::CurrentPerIsolateThreadData()->thread_id() ==
i::Thread::GetThreadLocalInt(i::Isolate::thread_id_key()));
ASSERT(i::Isolate::CurrentPerIsolateThreadData()->isolate() ==
i::Isolate::Current());
if (IsDead()) return false;
Isolate* isolate = Isolate::Current();
if (isolate->IsInitialized()) return true;
is_running_ = true;
has_been_setup_ = true;
has_fatal_error_ = false;
has_been_disposed_ = false;
return isolate->Init(des);
}
void V8::SetFatalError() {
is_running_ = false;
has_fatal_error_ = true;
}
void V8::TearDown() {
Isolate* isolate = Isolate::Current();
ASSERT(isolate->IsDefaultIsolate());
if (!has_been_setup_ || has_been_disposed_) return;
isolate->TearDown();
is_running_ = false;
has_been_disposed_ = true;
}
static uint32_t random_seed() {
if (FLAG_random_seed == 0) {
return random();
}
return FLAG_random_seed;
}
typedef struct {
uint32_t hi;
uint32_t lo;
} random_state;
// Random number generator using George Marsaglia's MWC algorithm.
static uint32_t random_base(random_state *state) {
// Initialize seed using the system random(). If one of the seeds
// should ever become zero again, or if random() returns zero, we
// avoid getting stuck with zero bits in hi or lo by re-initializing
// them on demand.
if (state->hi == 0) state->hi = random_seed();
if (state->lo == 0) state->lo = random_seed();
// Mix the bits.
state->hi = 36969 * (state->hi & 0xFFFF) + (state->hi >> 16);
state->lo = 18273 * (state->lo & 0xFFFF) + (state->lo >> 16);
return (state->hi << 16) + (state->lo & 0xFFFF);
}
// Used by JavaScript APIs
uint32_t V8::Random(Isolate* isolate) {
ASSERT(isolate == Isolate::Current());
// TODO(isolates): move lo and hi to isolate
static random_state state = {0, 0};
return random_base(&state);
}
// Used internally by the JIT and memory allocator for security
// purposes. So, we keep a different state to prevent informations
// leaks that could be used in an exploit.
uint32_t V8::RandomPrivate(Isolate* isolate) {
ASSERT(isolate == Isolate::Current());
// TODO(isolates): move lo and hi to isolate
static random_state state = {0, 0};
return random_base(&state);
}
bool V8::IdleNotification() {
// Returning true tells the caller that there is no need to call
// IdleNotification again.
if (!FLAG_use_idle_notification) return true;
// Tell the heap that it may want to adjust.
return HEAP->IdleNotification();
}
// Use a union type to avoid type-aliasing optimizations in GCC.
typedef union {
double double_value;
uint64_t uint64_t_value;
} double_int_union;
Object* V8::FillHeapNumberWithRandom(Object* heap_number, Isolate* isolate) {
uint64_t random_bits = Random(isolate);
// Make a double* from address (heap_number + sizeof(double)).
double_int_union* r = reinterpret_cast<double_int_union*>(
reinterpret_cast<char*>(heap_number) +
HeapNumber::kValueOffset - kHeapObjectTag);
// Convert 32 random bits to 0.(32 random bits) in a double
// by computing:
// ( 1.(20 0s)(32 random bits) x 2^20 ) - (1.0 x 2^20)).
const double binary_million = 1048576.0;
r->double_value = binary_million;
r->uint64_t_value |= random_bits;
r->double_value -= binary_million;
return heap_number;
}
void V8::InitializeOncePerProcess() {
ScopedLock lock(init_once_mutex);
if (init_once_called) return;
init_once_called = true;
// Setup the platform OS support.
OS::Setup();
#if defined(V8_TARGET_ARCH_ARM) && !defined(USE_ARM_EABI)
use_crankshaft_ = false;
#else
use_crankshaft_ = FLAG_crankshaft;
#endif
if (Serializer::enabled()) {
use_crankshaft_ = false;
}
CPU::Setup();
if (!CPU::SupportsCrankshaft()) {
use_crankshaft_ = false;
}
// Peephole optimization might interfere with deoptimization.
FLAG_peephole_optimization = !use_crankshaft_;
}
} } // namespace v8::internal
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