Add DoubleToSmi optimistically, preventing boxing/unboxing of doubles and propagate smi-nessof the …

runtime/vm/intermediate_language_x64.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/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/intermediate_language.h"
 
 #include "lib/error.h"
@@ skipping 2186 matching lines @@
   compiler->GenerateStaticCall(instance_call()->deopt_id(),
                                instance_call()->token_pos(),
                                target,
                                kNumberOfArguments,
                                Array::Handle(),  // No argument names.
                                locs());
   __ Bind(&done);
 }
 
 
+LocationSummary* DoubleToSmiInstr::MakeLocationSummary() const {
+  const intptr_t kNumInputs = 1;
+  const intptr_t kNumTemps = 1;
+  LocationSummary* result = new LocationSummary(
+      kNumInputs, kNumTemps, LocationSummary::kNoCall);
+  result->set_in(0, Location::RequiresXmmRegister());
+  result->set_out(Location:: Location::RequiresRegister());
+  result->set_temp(0, Location::RequiresRegister());
+  return result;
+}
+
+
+void DoubleToSmiInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
+  Label* deopt = compiler->AddDeoptStub(deopt_id(), kDeoptDoubleToSmi);
+  Register result = locs()->out().reg();
+  XmmRegister value = locs()->in(0).xmm_reg();
+  Register temp = locs()->temp(0).reg();
+
+  __ cvttsd2siq(result, value);
+  // Overflow is signalled with minint.
+  Label do_call, done;
+  // Check for overflow and that it fits into Smi.
+  __ movq(temp, result);
+  __ shlq(temp, Immediate(1));
+  __ j(OVERFLOW, deopt);
+  __ SmiTag(result);
+}
+
+
 LocationSummary* PolymorphicInstanceCallInstr::MakeLocationSummary() const {
   return MakeCallSummary();
 }
 
 
 void PolymorphicInstanceCallInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Label* deopt = compiler->AddDeoptStub(instance_call()->deopt_id(),
                                         kDeoptPolymorphicInstanceCallTestFail);
   if (ic_data().NumberOfChecks() == 0) {
     __ jmp(deopt);
@@ skipping 218 matching lines @@
 
 void ShiftMintOpInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   UNIMPLEMENTED();
 }
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_X64