Files
sdk/runtime/vm/virtual_memory.cc
T
Régis Crelier 0491d5cde7 Revert "[VM runtime] Dual mapping of executable pages."
This reverts commit 44186dfdcd.

Reason for revert: not working on vm-kernel-precomp-android-release-arm

Original change's description:
> [VM runtime] Dual mapping of executable pages.
> 
> Change-Id: Iaad78d324e25462ce951f4df26974a6a368c50b7
> Reviewed-on: https://dart-review.googlesource.com/c/93377
> Commit-Queue: Régis Crelier <regis@google.com>
> Reviewed-by: Ryan Macnak <rmacnak@google.com>

TBR=rmacnak@google.com,regis@google.com

Change-Id: I793ceee6252111eafbcbfe6e28268f4f6f2d7215
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/c/94989
Reviewed-by: Régis Crelier <regis@google.com>
Commit-Queue: Régis Crelier <regis@google.com>
2019-03-01 22:55:14 +00:00

40 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) {
ASSERT(Utils::IsAligned(new_size, PageSize()));
ASSERT(new_size <= size());
if (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