Reland "Refactor compilation dependency handling."

src/compiler.cc

Index: src/compiler.cc
diff --git a/src/compiler.cc b/src/compiler.cc
index 38c097e0c5a038637124d8dbd09233dac73a6ec3..ea5660d1e34e1224cee370833ecd2d2669ac6392 100644
--- a/src/compiler.cc
+++ b/src/compiler.cc
@@ -87,7 +87,7 @@ class CompilationInfoWithZone : public CompilationInfo {
   // called when cast as a CompilationInfo.
   virtual ~CompilationInfoWithZone() {
     DisableFutureOptimization();
-    RollbackDependencies();
+    dependencies()->Rollback();
     delete parse_info_;
     parse_info_ = nullptr;
   }
@@ -143,6 +143,7 @@ CompilationInfo::CompilationInfo(ParseInfo* parse_info, CodeStub* code_stub,
       osr_ast_id_(BailoutId::None()),
       zone_(zone),
       deferred_handles_(nullptr),
+      dependencies_(isolate, zone),
       bailout_reason_(kNoReason),
       prologue_offset_(Code::kPrologueOffsetNotSet),
       no_frame_ranges_(isolate->cpu_profiler()->is_profiling()
@@ -153,10 +154,7 @@ CompilationInfo::CompilationInfo(ParseInfo* parse_info, CodeStub* code_stub,
       opt_count_(has_shared_info() ? shared_info()->opt_count() : 0),
       parameter_count_(0),
       optimization_id_(-1),
-      aborted_due_to_dependency_change_(false),
-      osr_expr_stack_height_(0) {
-  std::fill_n(dependencies_, DependentCode::kGroupCount, nullptr);
-}
+      osr_expr_stack_height_(0) {}
 
 
 CompilationInfo::~CompilationInfo() {
@@ -166,60 +164,11 @@ CompilationInfo::~CompilationInfo() {
 #ifdef DEBUG
   // Check that no dependent maps have been added or added dependent maps have
   // been rolled back or committed.
-  for (int i = 0; i < DependentCode::kGroupCount; i++) {
-    DCHECK(!dependencies_[i]);
-  }
+  DCHECK(dependencies()->IsEmpty());
 #endif  // DEBUG
 }
 
 
-void CompilationInfo::CommitDependencies(Handle<Code> code) {
-  bool has_dependencies = false;
-  for (int i = 0; i < DependentCode::kGroupCount; i++) {
-    has_dependencies |=
-        dependencies_[i] != NULL && dependencies_[i]->length() > 0;
-  }
-  // Avoid creating a weak cell for code with no dependencies.
-  if (!has_dependencies) return;
-
-  AllowDeferredHandleDereference get_object_wrapper;
-  WeakCell* cell = *Code::WeakCellFor(code);
-  for (int i = 0; i < DependentCode::kGroupCount; i++) {
-    ZoneList<Handle<HeapObject> >* group_objects = dependencies_[i];
-    if (group_objects == NULL) continue;
-    DCHECK(!object_wrapper_.is_null());
-    for (int j = 0; j < group_objects->length(); j++) {
-      DependentCode::DependencyGroup group =
-          static_cast<DependentCode::DependencyGroup>(i);
-      Foreign* info = *object_wrapper();
-      DependentCode* dependent_code =
-          DependentCode::ForObject(group_objects->at(j), group);
-      dependent_code->UpdateToFinishedCode(group, info, cell);
-    }
-    dependencies_[i] = NULL;  // Zone-allocated, no need to delete.
-  }
-}
-
-
-void CompilationInfo::RollbackDependencies() {
-  AllowDeferredHandleDereference get_object_wrapper;
-  // Unregister from all dependent maps if not yet committed.
-  for (int i = 0; i < DependentCode::kGroupCount; i++) {
-    ZoneList<Handle<HeapObject> >* group_objects = dependencies_[i];
-    if (group_objects == NULL) continue;
-    for (int j = 0; j < group_objects->length(); j++) {
-      DependentCode::DependencyGroup group =
-          static_cast<DependentCode::DependencyGroup>(i);
-      Foreign* info = *object_wrapper();
-      DependentCode* dependent_code =
-          DependentCode::ForObject(group_objects->at(j), group);
-      dependent_code->RemoveCompilationInfo(group, info);
-    }
-    dependencies_[i] = NULL;  // Zone-allocated, no need to delete.
-  }
-}
-
-
 int CompilationInfo::num_parameters() const {
   return has_scope() ? scope()->num_parameters() : parameter_count_;
 }
@@ -493,7 +442,7 @@ OptimizedCompileJob::Status OptimizedCompileJob::CreateGraph() {
 
   if (graph_ == NULL) return SetLastStatus(BAILED_OUT);
 
-  if (info()->HasAbortedDueToDependencyChange()) {
+  if (info()->dependencies()->HasAborted()) {
     // Dependency has changed during graph creation. Let's try again later.
     return RetryOptimization(kBailedOutDueToDependencyChange);
   }
@@ -541,7 +490,7 @@ OptimizedCompileJob::Status OptimizedCompileJob::GenerateCode() {
     return last_status();
   }
 
-  DCHECK(!info()->HasAbortedDueToDependencyChange());
+  DCHECK(!info()->dependencies()->HasAborted());
   DisallowCodeDependencyChange no_dependency_change;
   DisallowJavascriptExecution no_js(isolate());
   {  // Scope for timer.
@@ -1522,7 +1471,7 @@ Handle<Code> Compiler::GetConcurrentlyOptimizedCode(OptimizedCompileJob* job) {
   if (job->last_status() == OptimizedCompileJob::SUCCEEDED) {
     if (shared->optimization_disabled()) {
       job->RetryOptimization(kOptimizationDisabled);
-    } else if (info->HasAbortedDueToDependencyChange()) {
+    } else if (info->dependencies()->HasAborted()) {
       job->RetryOptimization(kBailedOutDueToDependencyChange);
     } else if (isolate->debug()->has_break_points()) {
       job->RetryOptimization(kDebuggerHasBreakPoints);