Files
sdk/runtime/vm/virtual_memory.cc
T
Ryan Macnak a144e263ce Allocate from the root VMAR on Fuchsia.
Removes the need for the VmarList.

Overallocate VMOs instead of VMARs to get aligned memory.

Change-Id: I0c2c85e952b8c6958e28ac734b5ba54c7712a512
Reviewed-on: https://dart-review.googlesource.com/30383
Reviewed-by: Zach Anderson <zra@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2017-12-19 21:47:44 +00:00

42 lines
1.4 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() ==
region_.size()) && /* Don't create holes in reservation. */
FreeSubSegment(reinterpret_cast<void*>(start() + new_size),
size() - new_size)) {
reserved_.set_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);
MemoryRegion reserved(0, 0); // NULL reservation indicates VM should not
// attempt to free this memory.
VirtualMemory* memory = new VirtualMemory(region, reserved);
ASSERT(!memory->vm_owns_region());
return memory;
}
} // namespace dart