Files
sdk/runtime/vm/virtual_memory.cc
T
Ryan Macnak 97886e6dbf [vm, ffi] Remove special case for Fuchsia FFI callback thunks, take 2.
Require the embedder to place a blob containing the FFI callback stub at pkg/lib/ffi_callback_stub.bin. All blobs in the package can be loaded as executable VMOs.

Also reapply "Remove special case for simulator FFI callback thunks."

TEST=ci
Change-Id: I6ab4a73fc28fb750e45e67797b0bf9deee9d8b53
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/495840
Reviewed-by: Liam Appelbe <liama@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2026-05-04 10:45:15 -07:00

51 lines
1.7 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());
// We are not expected to call this with executable pages.
ASSERT(OffsetToExecutableAlias() == 0);
if (reserved_.size() ==
region_.size()) { // Don't create holes in reservation.
if (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(nullptr, 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;
}
VirtualMemory* VirtualMemory::Adopt(void* pointer, uword size) {
MemoryRegion region(pointer, size);
VirtualMemory* memory = new VirtualMemory(region, region);
ASSERT(memory->vm_owns_region());
return memory;
}
} // namespace dart