dart-sdk/runtime/vm/thread_state.h
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

119 lines
3.5 KiB
C++

// Copyright (c) 2019, 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.
#ifndef RUNTIME_VM_THREAD_STATE_H_
#define RUNTIME_VM_THREAD_STATE_H_
#include "include/dart_api.h"
#include "vm/os_thread.h"
namespace dart {
class HandleScope;
class LongJumpScope;
class Zone;
// ThreadState is a container for auxiliary thread-local state: e.g. it
// owns a stack of Zones for allocation and a stack of StackResources
// for stack unwinding.
//
// Important: this class is shared between compiler and runtime and
// as such it should not expose any runtime internals due to layering
// restrictions.
class ThreadState : public BaseThread {
public:
// The currently executing thread, or NULL if not yet initialized.
static ThreadState* Current() {
#if defined(HAS_C11_THREAD_LOCAL)
return OSThread::CurrentVMThread();
#else
BaseThread* thread = OSThread::GetCurrentTLS();
if (thread == NULL || thread->is_os_thread()) {
return NULL;
}
return static_cast<ThreadState*>(thread);
#endif
}
explicit ThreadState(bool is_os_thread);
virtual ~ThreadState();
// OSThread corresponding to this thread.
OSThread* os_thread() const { return os_thread_; }
void set_os_thread(OSThread* os_thread) { os_thread_ = os_thread; }
// The topmost zone used for allocation in this thread.
Zone* zone() const { return zone_; }
bool ZoneIsOwnedByThread(Zone* zone) const;
void IncrementMemoryCapacity(uintptr_t value) {
current_zone_capacity_ += value;
if (current_zone_capacity_ > zone_high_watermark_) {
zone_high_watermark_ = current_zone_capacity_;
}
}
void DecrementMemoryCapacity(uintptr_t value) {
ASSERT(current_zone_capacity_ >= value);
current_zone_capacity_ -= value;
}
uintptr_t current_zone_capacity() const { return current_zone_capacity_; }
uintptr_t zone_high_watermark() const { return zone_high_watermark_; }
void ResetHighWatermark() { zone_high_watermark_ = current_zone_capacity_; }
StackResource* top_resource() const { return top_resource_; }
void set_top_resource(StackResource* value) { top_resource_ = value; }
static intptr_t top_resource_offset() {
return OFFSET_OF(ThreadState, top_resource_);
}
LongJumpScope* long_jump_base() const { return long_jump_base_; }
void set_long_jump_base(LongJumpScope* value) { long_jump_base_ = value; }
bool IsValidZoneHandle(Dart_Handle object) const;
intptr_t CountZoneHandles() const;
bool IsValidScopedHandle(Dart_Handle object) const;
intptr_t CountScopedHandles() const;
virtual bool MayAllocateHandles() = 0;
HandleScope* top_handle_scope() const {
#if defined(DEBUG)
return top_handle_scope_;
#else
return 0;
#endif
}
void set_top_handle_scope(HandleScope* handle_scope) {
#if defined(DEBUG)
top_handle_scope_ = handle_scope;
#endif
}
private:
void set_zone(Zone* zone) { zone_ = zone; }
OSThread* os_thread_ = nullptr;
Zone* zone_ = nullptr;
uintptr_t current_zone_capacity_ = 0;
uintptr_t zone_high_watermark_ = 0;
StackResource* top_resource_ = nullptr;
LongJumpScope* long_jump_base_ = nullptr;
// This field is only used in the DEBUG builds, but we don't exclude it
// because it would cause RELEASE and DEBUG builds to have different
// offsets for various Thread fields that are used from generated code.
HandleScope* top_handle_scope_ = nullptr;
friend class ApiZone;
friend class StackZone;
};
} // namespace dart
#endif // RUNTIME_VM_THREAD_STATE_H_