Merge ConstantInstr -> UnboxDouble to UnboxedConstant. Reduces register usage and allows for variou…

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 "vm/dart_entry.h"
@@ skipping 210 matching lines @@
 
 void ConstantInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   // The register allocator drops constant definitions that have no uses.
   if (!locs()->out(0).IsInvalid()) {
     Register result = locs()->out(0).reg();
     __ LoadObject(result, value(), PP);
   }
 }
 
 
+LocationSummary* UnboxedConstantInstr::MakeLocationSummary(bool opt) const {
+  const intptr_t kNumInputs = 0;
+  const intptr_t kNumTemps = 0;
+  LocationSummary* locs =
+      new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
+  locs->set_out(0, Location::RequiresFpuRegister());
+  return locs;
+}
+
+
+void UnboxedConstantInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
+  // The register allocator drops constant definitions that have no uses.
+  if (!locs()->out(0).IsInvalid()) {
+    XmmRegister result = locs()->out(0).fpu_reg();
+    __ LoadDoubleConstant(result, Double::Cast(value()).value(), PP);
+  }
+}
+
+
 LocationSummary* AssertAssignableInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 3;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
   summary->set_in(0, Location::RegisterLocation(RAX));  // Value.
   summary->set_in(1, Location::RegisterLocation(RCX));  // Instantiator.
   summary->set_in(2, Location::RegisterLocation(RDX));  // Type arguments.
   summary->set_out(0, Location::RegisterLocation(RAX));
   return summary;
@@ skipping 5328 matching lines @@
                          PcDescriptors::kOther,
                          locs());
   __ Drop(ArgumentCount());  // Discard arguments.
 }
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_X64