Inline GrowableObjectArray capacity getter, use CHA to eliminate load/store fields class checks.

runtime/vm/flow_graph_optimizer.cc

 // 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/flow_graph_optimizer.h"
 
 #include "vm/bit_vector.h"
 #include "vm/cha.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/hash_map.h"
@@ skipping 517 matching lines @@
     field = cls.LookupInstanceField(field_name);
     if (!field.IsNull()) {
       return field.raw();
     }
     cls = cls.SuperClass();
   }
   return Field::null();
 }
 
 
+// Use CHA to determine if the call needs a class check: if the callee's
+// receiver is the same as the caller's receiver and there are no overriden
+// callee functions, then no class check is needed.
+bool FlowGraphOptimizer::InstanceCallNeedsClassCheck(
+    InstanceCallInstr* call) const {
+  if (!FLAG_use_cha) return true;
+  Definition* callee_receiver = call->ArgumentAt(0)->value()->definition();
+  ASSERT(callee_receiver != NULL);
+  const Function& function = flow_graph_->parsed_function().function();
+  if (function.IsDynamicFunction() &&
+      callee_receiver->IsParameter() &&
+      (callee_receiver->AsParameter()->index() == 0)) {
+    const intptr_t static_receiver_cid = Class::Handle(function.Owner()).id();
+    ZoneGrowableArray<intptr_t>* subclass_cids =
+        CHA::GetSubclassIdsOf(static_receiver_cid);
+    if (subclass_cids->is_empty()) {
+      // No subclasses, no check needed.
+      return false;
+    }
+    ZoneGrowableArray<Function*>* overriding_functions =
+        CHA::GetNamedInstanceFunctionsOf(*subclass_cids, call->function_name());
+    if (overriding_functions->is_empty()) {
+      // No overriding functions.
+      return false;
+    }
+  }
+  return true;
+}
+
 // Only unique implicit instance getters can be currently handled.
 bool FlowGraphOptimizer::TryInlineInstanceGetter(InstanceCallInstr* call) {
   ASSERT(call->HasICData());
   const ICData& ic_data = *call->ic_data();
   if (ic_data.NumberOfChecks() == 0) {
     // No type feedback collected.
     return false;
   }
   Function& target = Function::Handle();
   GrowableArray<intptr_t> class_ids;
   ic_data.GetCheckAt(0, &class_ids, &target);
   ASSERT(class_ids.length() == 1);
 
   if (target.kind() == RawFunction::kImplicitGetter) {
     if (!HasOneTarget(ic_data)) {
       // TODO(srdjan): Implement for mutiple targets.
       return false;
     }
     // Inline implicit instance getter.
     const String& field_name =
         String::Handle(Field::NameFromGetter(call->function_name()));
     const Field& field = Field::Handle(GetField(class_ids[0], field_name));
     ASSERT(!field.IsNull());
 
-    AddCheckClass(call, call->ArgumentAt(0)->value()->Copy());
+    if (InstanceCallNeedsClassCheck(call)) {
+      AddCheckClass(call, call->ArgumentAt(0)->value()->Copy());
+    }
     // Detach environment from the original instruction because it can't
     // deoptimize.
     call->set_env(NULL);
     LoadInstanceFieldInstr* load =
         new LoadInstanceFieldInstr(field, call->ArgumentAt(0)->value());
     call->ReplaceWith(load, current_iterator());
     RemovePushArguments(call);
     return true;
   }
 
@@ skipping 27 matching lines @@
     LoadVMFieldInstr* load = new LoadVMFieldInstr(
         call->ArgumentAt(0)->value(),
         length_offset,
         Type::ZoneHandle(Type::SmiType()));
     load->set_result_cid(kSmiCid);
     call->ReplaceWith(load, current_iterator());
     RemovePushArguments(call);
     return true;
   }
 
+  if (recognized_kind == MethodRecognizer::kGrowableArrayCapacity) {
+    // Check receiver class.
+    AddCheckClass(call, call->ArgumentAt(0)->value()->Copy());
+
+    // TODO(srdjan): type of load should be GrowableObjectArrayType.
+    LoadVMFieldInstr* data_load = new LoadVMFieldInstr(
+        call->ArgumentAt(0)->value(),
+        Array::data_offset(),
+        Type::ZoneHandle(Type::DynamicType()));
+    data_load->set_result_cid(kGrowableObjectArrayCid);
+    InsertBefore(call, data_load, NULL, Definition::kValue);
+
+    LoadVMFieldInstr* length_load = new LoadVMFieldInstr(
+        new Value(data_load),
+        Array::length_offset(),
+        Type::ZoneHandle(Type::SmiType()));
+    length_load->set_result_cid(kSmiCid);
+
+    call->ReplaceWith(length_load, current_iterator());
+    RemovePushArguments(call);
+    return true;
+  }
+
   if (recognized_kind == MethodRecognizer::kStringBaseLength) {
     if (!HasOneTarget(ic_data)) {
       // Target is not only StringBase_get_length.
       return false;
     }
     // Check receiver class.
     AddCheckClass(call, call->ArgumentAt(0)->value()->Copy());
 
     LoadVMFieldInstr* load = new LoadVMFieldInstr(
         call->ArgumentAt(0)->value(),
@@ skipping 61 matching lines @@
       return;
     }
     if ((op_kind == Token::kSET) && TryInlineInstanceSetter(instr)) {
       return;
     }
     if (TryInlineInstanceMethod(instr)) {
       return;
     }
     const ICData& unary_checks =
         ICData::ZoneHandle(instr->ic_data()->AsUnaryClassChecks());
-    if (FLAG_use_cha) {
-      // Check if receiver can have only one target, in which case
-      // we emit call without class checks.
-      Definition* receiver = instr->ArgumentAt(0)->value()->definition();
-      ASSERT(receiver != NULL);
-      const Function& function = flow_graph_->parsed_function().function();
-      if (function.IsDynamicFunction() &&
-          receiver->IsParameter() &&
-          (receiver->AsParameter()->index() == 0)) {
-        intptr_t static_receiver_cid = Class::Handle(function.Owner()).id();
-        ZoneGrowableArray<intptr_t>* subclass_cids =
-            CHA::GetSubclassIdsOf(static_receiver_cid);
-        ZoneGrowableArray<Function*>* overriding_functions =
-            CHA::GetNamedInstanceFunctionsOf(*subclass_cids,
-                                             instr->function_name());
-        if (overriding_functions->is_empty()) {
-          const bool call_with_checks = false;
-          PolymorphicInstanceCallInstr* call =
-              new PolymorphicInstanceCallInstr(instr, unary_checks,
-                                               call_with_checks);
-          instr->ReplaceWith(call, current_iterator());
-          return;
-        }
-      }
+    if (!InstanceCallNeedsClassCheck(instr)) {
+      const bool call_with_checks = false;
+      PolymorphicInstanceCallInstr* call =
+          new PolymorphicInstanceCallInstr(instr, unary_checks,
+                                           call_with_checks);
+      instr->ReplaceWith(call, current_iterator());
+      return;
     }
     const intptr_t kMaxChecks = 4;
     if (instr->ic_data()->NumberOfChecks() <= kMaxChecks) {
       bool call_with_checks;
       // TODO(srdjan): Add check class instr for mixed smi/non-smi.
       if (HasOneTarget(unary_checks) &&
           (unary_checks.GetReceiverClassIdAt(0) != kSmiCid)) {
         // Type propagation has not run yet, we cannot eliminate the check.
         AddCheckClass(instr, instr->ArgumentAt(0)->value()->Copy());
         // Call can still deoptimize, do not detach environment from instr.
@@ skipping 44 matching lines @@
     // Not an implicit setter.
     // TODO(srdjan): Inline special setters.
     return false;
   }
   // Inline implicit instance setter.
   const String& field_name =
       String::Handle(Field::NameFromSetter(instr->function_name()));
   const Field& field = Field::Handle(GetField(class_id, field_name));
   ASSERT(!field.IsNull());
 
-  AddCheckClass(instr, instr->ArgumentAt(0)->value()->Copy());
+  if (InstanceCallNeedsClassCheck(instr)) {
+    AddCheckClass(instr, instr->ArgumentAt(0)->value()->Copy());
+  }
   // Detach environment from the original instruction because it can't
   // deoptimize.
   instr->set_env(NULL);
   StoreInstanceFieldInstr* store = new StoreInstanceFieldInstr(
       field,
       instr->ArgumentAt(0)->value(),
       instr->ArgumentAt(1)->value());
   instr->ReplaceWith(store, current_iterator());
   RemovePushArguments(instr);
   return true;
@@ skipping 537 matching lines @@
       DirectChainedHashMap<Definition*> child_map(*map);  // Copy map.
       OptimizeRecursive(child, &child_map);
     } else {
       OptimizeRecursive(child, map);  // Reuse map for the last child.
     }
   }
 }
 
 
 }  // namespace dart