mirror of
https://github.com/dart-lang/sdk
synced 2024-11-05 18:22:09 +00:00
40 lines
1.3 KiB
C++
40 lines
1.3 KiB
C++
// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
|
|
// for details. All rights reserved. Use of this source code is governed by a
|
|
// BSD-style license that can be found in the LICENSE file.
|
|
|
|
#include "vm/virtual_memory.h"
|
|
|
|
#include "platform/assert.h"
|
|
#include "platform/utils.h"
|
|
|
|
namespace dart {
|
|
|
|
bool VirtualMemory::InSamePage(uword address0, uword address1) {
|
|
return (Utils::RoundDown(address0, PageSize()) ==
|
|
Utils::RoundDown(address1, PageSize()));
|
|
}
|
|
|
|
|
|
void VirtualMemory::Truncate(intptr_t new_size, bool try_unmap) {
|
|
ASSERT((new_size & (PageSize() - 1)) == 0);
|
|
ASSERT(new_size <= size());
|
|
if (try_unmap &&
|
|
(reserved_size_ == size()) && /* Don't create holes in reservation. */
|
|
FreeSubSegment(handle(), reinterpret_cast<void*>(start() + new_size),
|
|
size() - new_size)) {
|
|
reserved_size_ = new_size;
|
|
}
|
|
region_.Subregion(region_, 0, new_size);
|
|
}
|
|
|
|
|
|
VirtualMemory* VirtualMemory::ForImagePage(void* pointer, uword size) {
|
|
// Memory for precompilated instructions was allocated by the embedder, so
|
|
// create a VirtualMemory without allocating.
|
|
MemoryRegion region(pointer, size);
|
|
VirtualMemory* memory = new VirtualMemory(region);
|
|
memory->vm_owns_region_ = false;
|
|
return memory;
|
|
}
|
|
|
|
} // namespace dart
|