Visit the Optimized Code Map on first call rather than closure creation.

src/code-stubs-hydrogen.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/code-stubs.h"
 
 #include "src/bailout-reason.h"
 #include "src/crankshaft/hydrogen.h"
 #include "src/crankshaft/lithium.h"
 #include "src/field-index.h"
@@ skipping 79 matching lines @@
   HValue* UnmappedCase(HValue* elements, HValue* key, HValue* value);
   HValue* EmitKeyedSloppyArguments(HValue* receiver, HValue* key,
                                    HValue* value);
 
   HValue* BuildArrayConstructor(ElementsKind kind,
                                 AllocationSiteOverrideMode override_mode,
                                 ArgumentClass argument_class);
   HValue* BuildInternalArrayConstructor(ElementsKind kind,
                                         ArgumentClass argument_class);
 
-  // BuildCheckAndInstallOptimizedCode emits code to install the optimized
-  // function found in the optimized code map at map_index in js_function, if
-  // the function at map_index matches the given native_context. Builder is
-  // left in the "Then()" state after the install.
-  void BuildCheckAndInstallOptimizedCode(HValue* js_function,
-                                         HValue* native_context,
-                                         IfBuilder* builder,
-                                         HValue* optimized_map,
-                                         HValue* map_index);
-  void BuildInstallOptimizedCode(HValue* js_function, HValue* native_context,
-                                 HValue* code_object, HValue* literals);
-  void BuildInstallCode(HValue* js_function, HValue* shared_info);
-
-  HInstruction* LoadFromOptimizedCodeMap(HValue* optimized_map,
-                                         HValue* iterator,
-                                         int field_offset);
-  void BuildInstallFromOptimizedCodeMap(HValue* js_function,
-                                        HValue* shared_info,
-                                        HValue* native_context);
-
   HValue* BuildToString(HValue* input, bool convert);
   HValue* BuildToPrimitive(HValue* input, HValue* input_map);
 
  private:
   HValue* BuildArraySingleArgumentConstructor(JSArrayBuilder* builder);
   HValue* BuildArrayNArgumentsConstructor(JSArrayBuilder* builder,
                                           ElementsKind kind);
 
   base::SmartArrayPointer<HParameter*> parameters_;
   HValue* arguments_length_;
@@ skipping 1803 matching lines @@
 template <>
 HValue* CodeStubGraphBuilder<ToObjectStub>::BuildCodeStub() {
   HValue* receiver = GetParameter(TypeConversionDescriptor::kArgumentIndex);
   return BuildToObject(receiver);
 }
 
 
 Handle<Code> ToObjectStub::GenerateCode() { return DoGenerateCode(this); }
 
 
-void CodeStubGraphBuilderBase::BuildCheckAndInstallOptimizedCode(
-    HValue* js_function,
-    HValue* native_context,
-    IfBuilder* builder,
-    HValue* optimized_map,
-    HValue* map_index) {
-  HValue* osr_ast_id_none = Add<HConstant>(BailoutId::None().ToInt());
-  HValue* context_slot = LoadFromOptimizedCodeMap(
-      optimized_map, map_index, SharedFunctionInfo::kContextOffset);
-  context_slot = Add<HLoadNamedField>(context_slot, nullptr,
-                                      HObjectAccess::ForWeakCellValue());
-  HValue* osr_ast_slot = LoadFromOptimizedCodeMap(
-      optimized_map, map_index, SharedFunctionInfo::kOsrAstIdOffset);
-  HValue* code_object = LoadFromOptimizedCodeMap(
-      optimized_map, map_index, SharedFunctionInfo::kCachedCodeOffset);
-  code_object = Add<HLoadNamedField>(code_object, nullptr,
-                                     HObjectAccess::ForWeakCellValue());
-  builder->If<HCompareObjectEqAndBranch>(native_context,
-                                         context_slot);
-  builder->AndIf<HCompareObjectEqAndBranch>(osr_ast_slot, osr_ast_id_none);
-  builder->And();
-  builder->IfNot<HCompareObjectEqAndBranch>(code_object,
-                                            graph()->GetConstant0());
-  builder->Then();
-  HValue* literals = LoadFromOptimizedCodeMap(optimized_map,
-      map_index, SharedFunctionInfo::kLiteralsOffset);
-  literals = Add<HLoadNamedField>(literals, nullptr,
-                                  HObjectAccess::ForWeakCellValue());
-  IfBuilder maybe_deopt(this);
-  maybe_deopt.If<HCompareObjectEqAndBranch>(literals, graph()->GetConstant0());
-  maybe_deopt.ThenDeopt(Deoptimizer::kLiteralsWereDisposed);
-  maybe_deopt.End();
-
-  BuildInstallOptimizedCode(js_function, native_context, code_object, literals);
-
-  // The builder continues in the "then" after this function.
-}
-
-
-void CodeStubGraphBuilderBase::BuildInstallOptimizedCode(HValue* js_function,
-                                                         HValue* native_context,
-                                                         HValue* code_object,
-                                                         HValue* literals) {
-  Counters* counters = isolate()->counters();
-  AddIncrementCounter(counters->fast_new_closure_install_optimized());
-
-  // TODO(fschneider): Idea: store proper code pointers in the optimized code
-  // map and either unmangle them on marking or do nothing as the whole map is
-  // discarded on major GC anyway.
-  Add<HStoreCodeEntry>(js_function, code_object);
-  Add<HStoreNamedField>(js_function, HObjectAccess::ForLiteralsPointer(),
-                        literals);
-
-  // Now link a function into a list of optimized functions.
-  HValue* optimized_functions_list = Add<HLoadNamedField>(
-      native_context, nullptr,
-      HObjectAccess::ForContextSlot(Context::OPTIMIZED_FUNCTIONS_LIST));
-  Add<HStoreNamedField>(js_function,
-                        HObjectAccess::ForNextFunctionLinkPointer(),
-                        optimized_functions_list);
-
-  // This store is the only one that should have a write barrier.
-  Add<HStoreNamedField>(native_context,
-           HObjectAccess::ForContextSlot(Context::OPTIMIZED_FUNCTIONS_LIST),
-           js_function);
-}
-
-
-void CodeStubGraphBuilderBase::BuildInstallCode(HValue* js_function,
-                                                HValue* shared_info) {
-  Add<HStoreNamedField>(js_function,
-                        HObjectAccess::ForNextFunctionLinkPointer(),
-                        graph()->GetConstantUndefined());
-  HValue* code_object = Add<HLoadNamedField>(shared_info, nullptr,
-                                             HObjectAccess::ForCodeOffset());
-  Add<HStoreCodeEntry>(js_function, code_object);
-}
-
-
-HInstruction* CodeStubGraphBuilderBase::LoadFromOptimizedCodeMap(
-    HValue* optimized_map,
-    HValue* iterator,
-    int field_offset) {
-  // By making sure to express these loads in the form [<hvalue> + constant]
-  // the keyed load can be hoisted.
-  DCHECK(field_offset >= 0 && field_offset < SharedFunctionInfo::kEntryLength);
-  HValue* field_slot = iterator;
-  if (field_offset > 0) {
-    HValue* field_offset_value = Add<HConstant>(field_offset);
-    field_slot = AddUncasted<HAdd>(iterator, field_offset_value);
-  }
-  HInstruction* field_entry = Add<HLoadKeyed>(optimized_map, field_slot,
-                                              nullptr, nullptr, FAST_ELEMENTS);
-  return field_entry;
-}
-
-
-void CodeStubGraphBuilderBase::BuildInstallFromOptimizedCodeMap(
-    HValue* js_function,
-    HValue* shared_info,
-    HValue* native_context) {
-  Counters* counters = isolate()->counters();
-  Factory* factory = isolate()->factory();
-  IfBuilder is_optimized(this);
-  HInstruction* optimized_map = Add<HLoadNamedField>(
-      shared_info, nullptr, HObjectAccess::ForOptimizedCodeMap());
-  HValue* null_constant = Add<HConstant>(0);
-  is_optimized.If<HCompareObjectEqAndBranch>(optimized_map, null_constant);
-  is_optimized.Then();
-  {
-    BuildInstallCode(js_function, shared_info);
-  }
-  is_optimized.Else();
-  {
-    AddIncrementCounter(counters->fast_new_closure_try_optimized());
-    // The {optimized_map} points to fixed array of 4-element entries:
-    //   (native context, optimized code, literals, ast-id).
-    // Iterate through the {optimized_map} backwards. After the loop, if no
-    // matching optimized code was found, install unoptimized code.
-    //   for(i = map.length() - SharedFunctionInfo::kEntryLength;
-    //       i >= SharedFunctionInfo::kEntriesStart;
-    //       i -= SharedFunctionInfo::kEntryLength) { ... }
-    HValue* first_entry_index =
-        Add<HConstant>(SharedFunctionInfo::kEntriesStart);
-    HValue* shared_function_entry_length =
-        Add<HConstant>(SharedFunctionInfo::kEntryLength);
-    LoopBuilder loop_builder(this, context(), LoopBuilder::kPostDecrement,
-                             shared_function_entry_length);
-    HValue* array_length = Add<HLoadNamedField>(
-        optimized_map, nullptr, HObjectAccess::ForFixedArrayLength());
-    HValue* start_pos =
-        AddUncasted<HSub>(array_length, shared_function_entry_length);
-    HValue* slot_iterator =
-        loop_builder.BeginBody(start_pos, first_entry_index, Token::GTE);
-    {
-      IfBuilder done_check(this);
-      BuildCheckAndInstallOptimizedCode(js_function, native_context,
-                                        &done_check, optimized_map,
-                                        slot_iterator);
-      // Fall out of the loop
-      loop_builder.Break();
-    }
-    loop_builder.EndBody();
-
-    // If {slot_iterator} is less than the first entry index, then we failed to
-    // find a context-dependent code and try context-independent code next.
-    IfBuilder no_optimized_code_check(this);
-    no_optimized_code_check.If<HCompareNumericAndBranch>(
-        slot_iterator, first_entry_index, Token::LT);
-    no_optimized_code_check.Then();
-    {
-      IfBuilder shared_code_check(this);
-      HValue* shared_code =
-          Add<HLoadNamedField>(optimized_map, nullptr,
-                               HObjectAccess::ForOptimizedCodeMapSharedCode());
-      shared_code = Add<HLoadNamedField>(shared_code, nullptr,
-                                         HObjectAccess::ForWeakCellValue());
-      shared_code_check.IfNot<HCompareObjectEqAndBranch>(
-          shared_code, graph()->GetConstant0());
-      shared_code_check.Then();
-      {
-        // Store the context-independent optimized code.
-        HValue* literals = Add<HConstant>(factory->empty_fixed_array());
-        BuildInstallOptimizedCode(js_function, native_context, shared_code,
-                                  literals);
-      }
-      shared_code_check.Else();
-      {
-        // Store the unoptimized code.
-        BuildInstallCode(js_function, shared_info);
-      }
-    }
-  }
-}
-
-
 template<>
 HValue* CodeStubGraphBuilder<FastNewClosureStub>::BuildCodeStub() {
   Counters* counters = isolate()->counters();
   Factory* factory = isolate()->factory();
   HInstruction* empty_fixed_array =
       Add<HConstant>(factory->empty_fixed_array());
   HValue* shared_info = GetParameter(0);
 
   AddIncrementCounter(counters->fast_new_closure_total());
 
@@ skipping 19 matching lines @@
                         empty_fixed_array);
   Add<HStoreNamedField>(js_function, HObjectAccess::ForLiteralsPointer(),
                         empty_fixed_array);
   Add<HStoreNamedField>(js_function, HObjectAccess::ForPrototypeOrInitialMap(),
                         graph()->GetConstantHole());
   Add<HStoreNamedField>(
       js_function, HObjectAccess::ForSharedFunctionInfoPointer(), shared_info);
   Add<HStoreNamedField>(js_function, HObjectAccess::ForFunctionContextPointer(),
                         context());
 
-  // Initialize the code pointer in the function to be the one found in the
-  // shared function info object. But first check if there is an optimized
-  // version for our context.
-  BuildInstallFromOptimizedCodeMap(js_function, shared_info, native_context);
+  Handle<Code> lazy_builtin(
+      isolate()->builtins()->builtin(Builtins::kCompileLazy));
+  HConstant* lazy = Add<HConstant>(lazy_builtin);
+  Add<HStoreCodeEntry>(js_function, lazy);
+  Add<HStoreNamedField>(js_function,
+                        HObjectAccess::ForNextFunctionLinkPointer(),
+                        graph()->GetConstantUndefined());
 
   return js_function;
 }
 
 
 Handle<Code> FastNewClosureStub::GenerateCode() {
   return DoGenerateCode(this);
 }
 
 
@@ skipping 329 matching lines @@
   return Pop();
 }
 
 
 Handle<Code> KeyedLoadGenericStub::GenerateCode() {
   return DoGenerateCode(this);
 }
 
 }  // namespace internal
 }  // namespace v8