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// Copyright 2020 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#if !defined(CPPGC_CAGED_HEAP)
#error "Must be compiled with caged heap enabled"
#endif
#include "src/heap/cppgc/caged-heap.h"
#include "include/cppgc/internal/caged-heap-local-data.h"
#include "src/base/bounded-page-allocator.h"
#include "src/base/logging.h"
#include "src/heap/cppgc/globals.h"
namespace cppgc {
namespace internal {
STATIC_ASSERT(api_constants::kCagedHeapReservationSize ==
kCagedHeapReservationSize);
STATIC_ASSERT(api_constants::kCagedHeapReservationAlignment ==
kCagedHeapReservationAlignment);
namespace {
VirtualMemory ReserveCagedHeap(PageAllocator* platform_allocator) {
DCHECK_NOT_NULL(platform_allocator);
DCHECK_EQ(0u,
kCagedHeapReservationSize % platform_allocator->AllocatePageSize());
static constexpr size_t kAllocationTries = 4;
for (size_t i = 0; i < kAllocationTries; ++i) {
void* hint = reinterpret_cast<void*>(RoundDown(
reinterpret_cast<uintptr_t>(platform_allocator->GetRandomMmapAddr()),
kCagedHeapReservationAlignment));
VirtualMemory memory(platform_allocator, kCagedHeapReservationSize,
kCagedHeapReservationAlignment, hint);
if (memory.IsReserved()) return memory;
}
FATAL("Fatal process out of memory: Failed to reserve memory for caged heap");
UNREACHABLE();
}
std::unique_ptr<CagedHeap::AllocatorType> CreateBoundedAllocator(
v8::PageAllocator* platform_allocator, void* caged_heap_start) {
DCHECK(caged_heap_start);
auto start =
reinterpret_cast<CagedHeap::AllocatorType::Address>(caged_heap_start);
return std::make_unique<CagedHeap::AllocatorType>(
platform_allocator, start, kCagedHeapReservationSize, kPageSize);
}
} // namespace
CagedHeap::CagedHeap(HeapBase* heap_base, PageAllocator* platform_allocator)
: reserved_area_(ReserveCagedHeap(platform_allocator)) {
DCHECK_NOT_NULL(heap_base);
void* caged_heap_start = reserved_area_.address();
CHECK(platform_allocator->SetPermissions(
reserved_area_.address(),
RoundUp(sizeof(CagedHeapLocalData), platform_allocator->CommitPageSize()),
PageAllocator::kReadWrite));
auto* local_data =
new (reserved_area_.address()) CagedHeapLocalData(heap_base);
#if defined(CPPGC_YOUNG_GENERATION)
local_data->age_table.Reset(platform_allocator);
#endif
USE(local_data);
caged_heap_start = reinterpret_cast<void*>(
RoundUp(reinterpret_cast<uintptr_t>(caged_heap_start) +
sizeof(CagedHeapLocalData),
kPageSize));
bounded_allocator_ =
CreateBoundedAllocator(platform_allocator, caged_heap_start);
}
} // namespace internal
} // namespace cppgc
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