Optimize double.floor and double.ceil down to roundsd when SSE4.1 is available.

runtime/vm/intermediate_language_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/intermediate_language.h"
 
 #include "lib/error.h"
@@ skipping 2323 matching lines @@
   if (recognized_kind() == MethodRecognizer::kDoubleRound) {
     result->set_temp(0, Location::RequiresFpuRegister());
   }
   return result;
 }
 
 
 void DoubleToDoubleInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister value = locs()->in(0).fpu_reg();
   XmmRegister result = locs()->out().fpu_reg();
-  if (recognized_kind() == MethodRecognizer::kDoubleTruncate) {
-    __ roundsd(result, value,  Assembler::kRoundToZero);
-  } else {
-    XmmRegister temp = locs()->temp(0).fpu_reg();
-    __ DoubleRound(result, value, temp);
+  switch (recognized_kind()) {
+    case MethodRecognizer::kDoubleTruncate:
+      __ roundsd(result, value,  Assembler::kRoundToZero);
+      break;
+    case MethodRecognizer::kDoubleFloor:
+      __ roundsd(result, value,  Assembler::kRoundDown);
+      break;
+    case MethodRecognizer::kDoubleCeil:
+      __ roundsd(result, value,  Assembler::kRoundUp);
+      break;
+    case MethodRecognizer::kDoubleRound: {
+      XmmRegister temp = locs()->temp(0).fpu_reg();
+      __ DoubleRound(result, value, temp);
+      break;
+    }
+    default:
+      UNREACHABLE();
   }
 }
 
 
 LocationSummary* PolymorphicInstanceCallInstr::MakeLocationSummary() const {
   return MakeCallSummary();
 }
 
 
 void PolymorphicInstanceCallInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
@@ skipping 534 matching lines @@
                          PcDescriptors::kOther,
                          locs());
   __ Drop(2);  // Discard type arguments and receiver.
 }
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_X64