dart-sdk/runtime/vm/handles.cc
Vyacheslav Egorov f496e538f4 [vm] Decouple assemblers from runtime.
This is the next step towards preventing compiler from directly peeking
into runtime and instead interact with runtime through a well defined
surface. The goal of the refactoring to locate all places where compiler
accesses some runtime information and partion those accesses into two
categories:

- creating objects in the host runtime (e.g. allocating strings, numbers, etc)
during compilation;
- accessing properties of the target runtime (e.g. offsets of fields) to
embed those into the generated code;

This change introduces dart::compiler and dart::compiler::target namespaces.

All code in the compiler will gradually be moved into dart::compiler namespace.
One of the motivations for this change is to be able to prevent access to
globally defined host constants like kWordSize by shadowing them in the
dart::compiler namespace.

The nested namespace dart::compiler::target hosts all information about
target runtime that compiler could access, e.g. compiler::target::kWordSize
defines word size of the target which will eventually be made different
from the host kWordSize (defined by dart::kWordSize).

The API for compiler to runtime interaction is placed into compiler_api.h.

Note that we still permit runtime to access compiler internals directly -
this is not going to be decoupled as part of this work.

Issue https://github.com/dart-lang/sdk/issues/31709

Change-Id: If4396d295879391becfa6c38d4802bbff81f5b20
Reviewed-on: https://dart-review.googlesource.com/c/90242
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2019-01-25 16:45:13 +00:00

105 lines
3.2 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/handles.h"
#include "platform/assert.h"
#include "platform/utils.h"
#include "vm/dart_api_state.h"
#include "vm/flags.h"
#include "vm/os.h"
#include "vm/raw_object.h"
#include "vm/visitor.h"
#include "vm/zone.h"
#include "vm/handles_impl.h"
namespace dart {
DEFINE_FLAG(bool, verify_handles, false, "Verify handles.");
VMHandles::~VMHandles() {
if (FLAG_trace_handles) {
OS::PrintErr("*** Handle Counts for 0x(%" Px "):Zone = %d,Scoped = %d\n",
reinterpret_cast<intptr_t>(this), CountZoneHandles(),
CountScopedHandles());
OS::PrintErr("*** Deleting VM handle block 0x%" Px "\n",
reinterpret_cast<intptr_t>(this));
}
}
void VMHandles::VisitObjectPointers(ObjectPointerVisitor* visitor) {
return Handles<kVMHandleSizeInWords, kVMHandlesPerChunk,
kOffsetOfRawPtr>::VisitObjectPointers(visitor);
}
#if defined(DEBUG)
static bool IsCurrentApiNativeScope(Zone* zone) {
ApiNativeScope* scope = ApiNativeScope::Current();
return (scope != NULL) && (scope->zone() == zone);
}
#endif // DEBUG
uword VMHandles::AllocateHandle(Zone* zone) {
DEBUG_ASSERT(!IsCurrentApiNativeScope(zone));
return Handles<kVMHandleSizeInWords, kVMHandlesPerChunk,
kOffsetOfRawPtr>::AllocateHandle(zone);
}
uword VMHandles::AllocateZoneHandle(Zone* zone) {
DEBUG_ASSERT(!IsCurrentApiNativeScope(zone));
return Handles<kVMHandleSizeInWords, kVMHandlesPerChunk,
kOffsetOfRawPtr>::AllocateZoneHandle(zone);
}
bool VMHandles::IsZoneHandle(uword handle) {
return Handles<kVMHandleSizeInWords, kVMHandlesPerChunk,
kOffsetOfRawPtr>::IsZoneHandle(handle);
}
int VMHandles::ScopedHandleCount() {
Thread* thread = Thread::Current();
ASSERT(thread->zone() != NULL);
VMHandles* handles = thread->zone()->handles();
return handles->CountScopedHandles();
}
int VMHandles::ZoneHandleCount() {
Thread* thread = Thread::Current();
ASSERT(thread->zone() != NULL);
VMHandles* handles = thread->zone()->handles();
return handles->CountZoneHandles();
}
void HandleScope::Initialize() {
ASSERT(thread()->MayAllocateHandles());
VMHandles* handles = thread()->zone()->handles();
ASSERT(handles != NULL);
saved_handle_block_ = handles->scoped_blocks_;
saved_handle_slot_ = handles->scoped_blocks_->next_handle_slot();
#if defined(DEBUG)
link_ = thread()->top_handle_scope();
thread()->set_top_handle_scope(this);
#endif
}
HandleScope::HandleScope(ThreadState* thread) : StackResource(thread) {
Initialize();
}
HandleScope::~HandleScope() {
ASSERT(thread()->zone() != NULL);
VMHandles* handles = thread()->zone()->handles();
ASSERT(handles != NULL);
handles->scoped_blocks_ = saved_handle_block_;
handles->scoped_blocks_->set_next_handle_slot(saved_handle_slot_);
#if defined(DEBUG)
handles->VerifyScopedHandleState();
handles->ZapFreeScopedHandles();
ASSERT(thread()->top_handle_scope() == this);
thread()->set_top_handle_scope(link_);
#endif
}
} // namespace dart