Add fast Smi op version of switchable instance calls.

runtime/vm/flow_graph_compiler_x64.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/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/ast_printer.h"
@@ skipping 1307 matching lines @@
     intptr_t deopt_id,
     intptr_t token_pos,
     LocationSummary* locs) {
   __ Comment("SwitchableCall");
   __ movq(RDI, Address(RSP, (argument_count - 1) * kWordSize));
   if (ic_data.NumArgsTested() == 1) {
     __ LoadUniqueObject(RBX, ic_data);
     __ CallPatchable(*StubCode::ICLookup_entry());
   } else {
     const String& name = String::Handle(zone(), ic_data.target_name());
-    const Array& arguments_descriptor =
-        Array::ZoneHandle(zone(), ic_data.arguments_descriptor());
-    ASSERT(!arguments_descriptor.IsNull() &&
-           (arguments_descriptor.Length() > 0));
-    const MegamorphicCache& cache = MegamorphicCache::ZoneHandle(zone(),
-        MegamorphicCacheTable::Lookup(isolate(), name, arguments_descriptor));
 
-    __ LoadUniqueObject(RBX, cache);
-    __ CallPatchable(*StubCode::MegamorphicLookup_entry());
+    if (name.raw() == Symbols::Plus().raw()) {
+      __ LoadUniqueObject(RBX, ic_data);
+      __ CallPatchable(*StubCode::ICSmiAddLookup_entry());
+    } else if (name.raw() == Symbols::Minus().raw()) {
+      __ LoadUniqueObject(RBX, ic_data);
+      __ CallPatchable(*StubCode::ICSmiSubLookup_entry());
+    } else if (name.raw() == Symbols::Equals().raw()) {
+      __ LoadUniqueObject(RBX, ic_data);
+      __ CallPatchable(*StubCode::ICSmiEqualLookup_entry());
+    } else {
+      const Array& arguments_descriptor =
+          Array::ZoneHandle(zone(), ic_data.arguments_descriptor());
+      ASSERT(!arguments_descriptor.IsNull() &&
+             (arguments_descriptor.Length() > 0));
+      const MegamorphicCache& cache = MegamorphicCache::ZoneHandle(zone(),
+          MegamorphicCacheTable::Lookup(isolate(), name, arguments_descriptor));
+
+      __ LoadUniqueObject(RBX, cache);
+      __ CallPatchable(*StubCode::MegamorphicLookup_entry());
+    }
   }
-  __ call(RCX);
+  __ call(RCX);  // A fast Smi operation may return past this call.
 
   AddCurrentDescriptor(RawPcDescriptors::kOther,
                        Thread::kNoDeoptId, token_pos);
   RecordSafepoint(locs);
   const intptr_t deopt_id_after = Thread::ToDeoptAfter(deopt_id);
   if (is_optimizing()) {
     AddDeoptIndexAtCall(deopt_id_after, token_pos);
   } else {
     // Add deoptimization continuation point after the call and before the
     // arguments are removed.
@@ skipping 446 matching lines @@
   __ movups(reg, Address(RSP, 0));
   __ AddImmediate(RSP, Immediate(kFpuRegisterSize));
 }
 
 
 #undef __
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64