Convert UnaryOpStub to a HydrogenCodeStub

src/code-stubs-hydrogen.cc

Index: src/code-stubs-hydrogen.cc
diff --git a/src/code-stubs-hydrogen.cc b/src/code-stubs-hydrogen.cc
index 11cd307451cc0017429d0ea84be0bbdc410982a5..f26ddf057768acdf65ece8a19f5e31f473a1e27f 100644
--- a/src/code-stubs-hydrogen.cc
+++ b/src/code-stubs-hydrogen.cc
@@ -750,6 +750,64 @@ HValue* CodeStubGraphBuilder<CompareNilICStub>::BuildCodeInitializedStub() {
 }
 
 
+Handle<Code> UnaryOpStub::GenerateCode() {
+  return DoGenerateCode(this);
+}
+
+
+HInstruction* UnaryOpStub::ToHInstruction(HValue* input,
+    Handle<Type> type, HGraphBuilder* builder, HContext* context) {
+  switch (operation_) {
+    default:
+      UNREACHABLE();
+    case Token::SUB: {
+        HInstruction* minus = HMul::New(builder->zone(), context,
+            input, builder->graph()->GetConstantMinus1());
+        if (type->Maybe(Type::Double())) {
+          // We have to force a double multiplication if we have seen double,
+          // otherwise we will deopt again.
+          minus->AssumeRepresentation(Representation::Double());

[danno, 2013/06/21 16:38:04]

Try to move this out with the other representation changes so that this code can
be shared 100% with hydrogen.

+        }
+        return minus;
+      }
+    case Token::BIT_NOT:
+      return new(builder->zone()) HBitNot(input);
+  }
+}
+
+
+template <>
+HValue* CodeStubGraphBuilder<UnaryOpStub>::BuildCodeInitializedStub() {
+  UnaryOpStub* stub = casted_stub();

[danno, 2013/06/21 16:38:04]

Please share this code with hydrogen, it should be identical to the inlined
instructions in the optimized code. We do this for other stubs by putting 

+  Handle<Type> type = stub->GetType(graph()->isolate());
+  HValue* input = GetParameter(0);
+
+  if (!type->Is(Type::Number())) {
+    // If we expect to see other things than Numbers, we will create a generic
+    // stub, which handles all numbers and calls into the runtime for the rest.
+    IfBuilder if_number(this);
+    if_number.If<HIsNumberAndBranch>(input);
+    if_number.Then();
+      HInstruction* res = stub->ToHInstruction(input, type, this, context());
+      if_number.Return(AddInstruction(res));
+    if_number.Else();
+      AddInstruction(new(zone()) HPushArgument(GetParameter(0)));
+      if_number.Return(AddInstruction(new(zone()) HCallConstantFunction(
+            stub->ToJSFunction(isolate()), 1)));
+    if_number.End();
+    return graph()->GetConstantUndefined();
+  }
+
+  if (type->Is(Type::Integer31())) {
+    AddInstruction(new(zone()) HCheckSmi(input));

[danno, 2013/06/21 16:38:04]

Try to avoid the explicit checks by using force representation here and below
for double.

+  } else if (type->Is(Type::Double())) {
+    AddInstruction(new(zone()) HCheckNonSmi(input));
+  }
+
+  return AddInstruction(stub->ToHInstruction(input, type, this, context()));
+}
+
+
 Handle<Code> CompareNilICStub::GenerateCode() {
   return DoGenerateCode(this);
 }