Recognize and optimize a.runtimeType == b.runtimeType pattern.

runtime/vm/aot_optimizer.cc

 // Copyright (c) 2013, 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/aot_optimizer.h"
 
 #include "vm/bit_vector.h"
 #include "vm/branch_optimizer.h"
 #include "vm/cha.h"
 #include "vm/compiler.h"
@@ skipping 70 matching lines @@
               call->checked_argument_count(), false));
           call->set_ic_data(&ic_data);
         }
       }
     }
     current_iterator_ = NULL;
   }
 }
 
 
+bool AotOptimizer::RecognizeRuntimeTypeGetter(InstanceCallInstr* call) {
+  if ((precompiler_ == NULL) || !precompiler_->get_runtime_type_is_unique()) {
+    return false;
+  }
+
+  if (call->function_name().raw() != Symbols::GetRuntimeType().raw()) {
+    return false;
+  }
+
+  // There is only a single function Object.get:runtimeType that can be invoked
+  // by this call. Convert dynamic invocation to a static one.
+  const Class& cls =
+      Class::Handle(Z, thread()->isolate()->object_store()->object_class());

[siva, 2016/09/29 02:28:20]

there seems to be an I in this file so I->object_store() ?

[Vyacheslav Egorov (Google), 2016/09/29 15:01:43]

Done.

+  const Array& args_desc_array = Array::Handle(Z,
+      ArgumentsDescriptor::New(call->ArgumentCount(),
+                               call->argument_names()));
+  ArgumentsDescriptor args_desc(args_desc_array);
+  const Function& function = Function::Handle(Z,
+      Resolver::ResolveDynamicForReceiverClass(
+          cls,
+          call->function_name(),
+          args_desc));
+  ASSERT(!function.IsNull());
+
+  ZoneGrowableArray<PushArgumentInstr*>* args =
+      new (Z) ZoneGrowableArray<PushArgumentInstr*>(
+          call->ArgumentCount());
+  for (intptr_t i = 0; i < call->ArgumentCount(); i++) {
+    args->Add(call->PushArgumentAt(i));
+  }
+  StaticCallInstr* static_call = new (Z) StaticCallInstr(
+      call->token_pos(),
+      Function::ZoneHandle(Z, function.raw()),
+      call->argument_names(),
+      args,
+      call->deopt_id());
+  static_call->set_result_cid(kTypeCid);
+  call->ReplaceWith(static_call, current_iterator());
+  return true;
+}
+
+
 // Optimize instance calls using cid.  This is called after optimizer
 // converted instance calls to instructions. Any remaining
 // instance calls are either megamorphic calls, cannot be optimized or
 // have no runtime type feedback collected.
 // Attempts to convert an instance call (IC call) using propagated class-ids,
 // e.g., receiver class id, guarded-cid, or by guessing cid-s.
 void AotOptimizer::ApplyClassIds() {
   ASSERT(current_iterator_ == NULL);
   for (BlockIterator block_it = flow_graph_->reverse_postorder_iterator();
        !block_it.Done();
        block_it.Advance()) {
     ForwardInstructionIterator it(block_it.Current());
     current_iterator_ = &it;
     for (; !it.Done(); it.Advance()) {
       Instruction* instr = it.Current();
       if (instr->IsInstanceCall()) {
         InstanceCallInstr* call = instr->AsInstanceCall();
-        if (call->HasICData()) {
+        if (RecognizeRuntimeTypeGetter(call)) {

[Florian Schneider, 2016/09/28 22:49:24]

Any reason why this is here and not in AotOptimizer::VisitInstanceCall?

[Vyacheslav Egorov (Google), 2016/09/29 00:31:22]

Because we will never get into VisitInstanceCall if we know nothing about the
receiver - thus we can't create ICData for this call and TryCreateICData will
return false. However this inlining works even if we know nothing about the
receiver. 

[Florian Schneider, 2016/09/29 18:03:28]

Yes, I meant that the ApplyICData phase always visits all instance calls (and
invokes VisitInstanceCall) I'm not sure why we actually have ApplyClassIds and
ApplyICData separate, but that would be another clean up.

[Vyacheslav Egorov (Google), 2016/09/30 09:56:28]

Fair enough. Moved it into VisitInstanceCall.

+          continue;
+        } else if (call->HasICData()) {
           if (TryCreateICData(call)) {
             VisitInstanceCall(call);
           }
         }
       }
     }
     current_iterator_ = NULL;
   }
 }
 
@@ skipping 480 matching lines @@
       to_remove_right->RemoveFromGraph();
     }
     return true;
   }
   return false;
 }
 
 
 static bool SmiFitsInDouble() { return kSmiBits < 53; }
 
+static bool IsGetRuntimeType(Definition* defn) {
+  StaticCallInstr* call = defn->AsStaticCall();
+  return (call != NULL) &&
+      (call->function().recognized_kind() ==
+          MethodRecognizer::kObjectRuntimeType);
+}
+
 bool AotOptimizer::TryReplaceWithEqualityOp(InstanceCallInstr* call,
                                             Token::Kind op_kind) {
   const ICData& ic_data = *call->ic_data();
   ASSERT(ic_data.NumArgsTested() == 2);
 
   ASSERT(call->ArgumentCount() == 2);
   Definition* left = call->ArgumentAt(0);
   Definition* right = call->ArgumentAt(1);
 
+  // Recognize a.runtimeType == b.runtimeType and fold it into
+  // Object._haveSameRuntimeType(a, b).
+  if (IsGetRuntimeType(left) && left->input_use_list()->IsSingleUse() &&
+      IsGetRuntimeType(right) && right->input_use_list()->IsSingleUse()) {
+    const Class& cls =
+        Class::Handle(Z, thread()->isolate()->object_store()->object_class());

[siva, 2016/09/29 02:28:20]

Ditto comment about I

[Vyacheslav Egorov (Google), 2016/09/29 15:01:43]

Done.

+    const Function& hasSameRuntimeType = Function::ZoneHandle(Z,
+        cls.LookupStaticFunctionAllowPrivate(Symbols::HaveSameRuntimeType()));
+    ASSERT(!hasSameRuntimeType.IsNull());
+
+    ZoneGrowableArray<PushArgumentInstr*>* args =
+        new (Z) ZoneGrowableArray<PushArgumentInstr*>(2);
+    PushArgumentInstr* arg = new (Z) PushArgumentInstr(
+        new (Z) Value(left->ArgumentAt(0)));
+    InsertBefore(call, arg, NULL, FlowGraph::kEffect);
+    args->Add(arg);
+    arg = new (Z) PushArgumentInstr(
+         new (Z) Value(right->ArgumentAt(0)));
+    InsertBefore(call, arg, NULL, FlowGraph::kEffect);
+    args->Add(arg);
+    StaticCallInstr* static_call = new (Z) StaticCallInstr(
+        call->token_pos(),
+        hasSameRuntimeType,
+        Object::null_array(),  // argument_names
+        args,
+        call->deopt_id());
+    static_call->set_result_cid(kBoolCid);
+    ReplaceCall(call, static_call);
+    return true;
+  }
+
   intptr_t cid = kIllegalCid;
   if (HasOnlyTwoOf(ic_data, kOneByteStringCid)) {
-    if (TryStringLengthOneEquality(call, op_kind)) {
-      return true;
-    } else {
-      return false;
-    }
+    return TryStringLengthOneEquality(call, op_kind);
   } else if (HasOnlyTwoOf(ic_data, kSmiCid)) {
     InsertBefore(call,
                  new(Z) CheckSmiInstr(new(Z) Value(left),
                                       call->deopt_id(),
                                       call->token_pos()),
                  call->env(),
                  FlowGraph::kEffect);
     InsertBefore(call,
                  new(Z) CheckSmiInstr(new(Z) Value(right),
                                       call->deopt_id(),
@@ skipping 1543 matching lines @@
                                   check->env(), FlowGraph::kEffect);
         current_iterator()->RemoveCurrentFromGraph();
       }
     }
   }
 }
 
 #endif  // DART_PRECOMPILER
 
 }  // namespace dart