Bisect clang

tools/clang/blink_gc_plugin/RecordInfo.h

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// This file provides a wrapper for CXXRecordDecl that accumulates GC related
+// information about a class. Accumulated information is memoized and the info
+// objects are stored in a RecordCache.
+
+#ifndef TOOLS_BLINK_GC_PLUGIN_RECORD_INFO_H_
+#define TOOLS_BLINK_GC_PLUGIN_RECORD_INFO_H_
+
+#include <map>
+#include <vector>
+
+#include "Edge.h"
+
+#include "clang/AST/AST.h"
+#include "clang/AST/CXXInheritance.h"
+
+class RecordCache;
+
+// A potentially tracable and/or lifetime affecting point in the object graph.
+class GraphPoint {
+ public:
+  GraphPoint() : traced_(false) {}
+  virtual ~GraphPoint() {}
+  void MarkTraced() { traced_ = true; }
+  bool IsProperlyTraced() { return traced_ || !NeedsTracing().IsNeeded(); }
+  virtual const TracingStatus NeedsTracing() = 0;
+
+ private:
+  bool traced_;
+};
+
+class BasePoint : public GraphPoint {
+ public:
+  BasePoint(const clang::CXXBaseSpecifier& spec,
+            RecordInfo* info,
+            const TracingStatus& status)
+      : spec_(spec), info_(info), status_(status) {}
+  const TracingStatus NeedsTracing() { return status_; }
+  const clang::CXXBaseSpecifier& spec() { return spec_; }
+  RecordInfo* info() { return info_; }
+
+ private:
+  const clang::CXXBaseSpecifier& spec_;
+  RecordInfo* info_;
+  TracingStatus status_;
+};
+
+class FieldPoint : public GraphPoint {
+ public:
+  FieldPoint(clang::FieldDecl* field, Edge* edge)
+      : field_(field), edge_(edge) {}
+  const TracingStatus NeedsTracing() {
+    return edge_->NeedsTracing(Edge::kRecursive);
+  }
+  clang::FieldDecl* field() { return field_; }
+  Edge* edge() { return edge_; }
+
+ private:
+  clang::FieldDecl* field_;
+  Edge* edge_;
+
+  friend class RecordCache;
+  void deleteEdge() { delete edge_; }
+};
+
+// Wrapper class to lazily collect information about a C++ record.
+class RecordInfo {
+ public:
+  typedef std::map<clang::CXXRecordDecl*, BasePoint> Bases;
+  typedef std::map<clang::FieldDecl*, FieldPoint> Fields;
+  typedef std::vector<const clang::Type*> TemplateArgs;
+
+  ~RecordInfo();
+
+  clang::CXXRecordDecl* record() const { return record_; }
+  const std::string& name() const { return name_; }
+  Fields& GetFields();
+  Bases& GetBases();
+  clang::CXXMethodDecl* GetTraceMethod();
+  clang::CXXMethodDecl* GetTraceDispatchMethod();
+  clang::CXXMethodDecl* GetFinalizeDispatchMethod();
+
+  bool GetTemplateArgs(size_t count, TemplateArgs* output_args);
+
+  bool IsHeapAllocatedCollection();
+  bool IsGCDerived();
+  bool IsGCAllocated();
+  bool IsGCFinalized();
+  bool IsGCMixin();
+  bool IsStackAllocated();
+  bool IsNonNewable();
+  bool IsOnlyPlacementNewable();
+  bool IsGCMixinInstance();
+  bool IsEagerlyFinalized();
+
+  bool HasDefinition();
+
+  clang::CXXMethodDecl* DeclaresNewOperator();
+
+  bool RequiresTraceMethod();
+  bool NeedsFinalization();
+  bool DeclaresGCMixinMethods();
+  bool DeclaresLocalTraceMethod();
+  TracingStatus NeedsTracing(Edge::NeedsTracingOption);
+  clang::CXXMethodDecl* InheritsNonVirtualTrace();
+  bool IsConsideredAbstract();
+
+  static clang::CXXRecordDecl* GetDependentTemplatedDecl(const clang::Type&);
+
+ private:
+  RecordInfo(clang::CXXRecordDecl* record, RecordCache* cache);
+
+  void walkBases();
+
+  Fields* CollectFields();
+  Bases* CollectBases();
+  void DetermineTracingMethods();
+  bool InheritsTrace();
+
+  Edge* CreateEdge(const clang::Type* type);
+
+  RecordCache* cache_;
+  clang::CXXRecordDecl* record_;
+  const std::string name_;
+  TracingStatus fields_need_tracing_;
+  Bases* bases_;
+  Fields* fields_;
+
+  enum CachedBool { kFalse = 0, kTrue = 1, kNotComputed = 2 };
+  CachedBool is_stack_allocated_;
+  CachedBool is_non_newable_;
+  CachedBool is_only_placement_newable_;
+  CachedBool does_need_finalization_;
+  CachedBool has_gc_mixin_methods_;
+  CachedBool is_declaring_local_trace_;
+  CachedBool is_eagerly_finalized_;
+
+  bool determined_trace_methods_;
+  clang::CXXMethodDecl* trace_method_;
+  clang::CXXMethodDecl* trace_dispatch_method_;
+  clang::CXXMethodDecl* finalize_dispatch_method_;
+
+  bool is_gc_derived_;
+
+  std::vector<std::string> gc_base_names_;
+
+  friend class RecordCache;
+};
+
+class RecordCache {
+ public:
+  RecordInfo* Lookup(clang::CXXRecordDecl* record);
+
+  RecordInfo* Lookup(const clang::CXXRecordDecl* record) {
+    return Lookup(const_cast<clang::CXXRecordDecl*>(record));
+  }
+
+  RecordInfo* Lookup(clang::DeclContext* decl) {
+    return Lookup(clang::dyn_cast<clang::CXXRecordDecl>(decl));
+  }
+
+  RecordInfo* Lookup(const clang::Type* type) {
+    return Lookup(type->getAsCXXRecordDecl());
+  }
+
+  RecordInfo* Lookup(const clang::QualType& type) {
+    return Lookup(type.getTypePtr());
+  }
+
+  ~RecordCache() {
+    for (Cache::iterator it = cache_.begin(); it != cache_.end(); ++it) {
+      if (!it->second.fields_)
+        continue;
+      for (RecordInfo::Fields::iterator fit = it->second.fields_->begin();
+        fit != it->second.fields_->end();
+        ++fit) {
+        fit->second.deleteEdge();
+      }
+    }
+  }
+
+ private:
+  typedef std::map<clang::CXXRecordDecl*, RecordInfo> Cache;
+  Cache cache_;
+};
+
+#endif  // TOOLS_BLINK_GC_PLUGIN_RECORD_INFO_H_