Enable Float32Array_getIndexed on X64 now that cvtss2sd is implemented

runtime/vm/intrinsifier_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/intrinsifier.h"
 
 #include "vm/assembler.h"
@@ skipping 500 matching lines @@
                             RBX,
                             TIMES_2,
                             Uint32Array::data_offset()));
   __ SmiTag(RAX);
   __ ret();
   __ Bind(&fall_through);
   return false;
 }
 
 bool Intrinsifier::Float32Array_getIndexed(Assembler* assembler) {
-  // Temporary fix until cvtss2sd implemented.
-  /*Label fall_through;
+  Label fall_through;
   TestByteArrayIndex(assembler, &fall_through);
   // After TestByteArrayIndex:
   // * RAX has the base address of the byte array.
   // * RBX has the index into the array.
   // RBX contains the SMI index which is shifted left by 1.
   // This shift means we only multiply the index by 2 not 4 (sizeof float).
   // Load single precision float into XMM7.
   __ movss(XMM7, FieldAddress(RAX, RBX, TIMES_2,
                               Float32Array::data_offset()));
   // Convert into a double precision float.
   __ cvtss2sd(XMM7, XMM7);
   // Allocate a double instance.
   const Class& double_class = Class::Handle(
                           Isolate::Current()->object_store()->double_class());
   AssemblerMacros::TryAllocate(assembler,
                                double_class,
                                &fall_through,
                                Assembler::kNearJump, RAX);
   // Store XMM7 into double instance.
   __ movsd(FieldAddress(RAX, Double::value_offset()), XMM7);
   __ ret();
-  __ Bind(&fall_through); */
+  __ Bind(&fall_through);
   return false;
 }
 
 bool Intrinsifier::Float32Array_setIndexed(Assembler* assembler) {
     return false;
 }
 
 
 // Tests if two top most arguments are smis, jumps to label not_smi if not.
 // Topmost argument is in RAX.
@@ skipping 862 matching lines @@
   __ LoadObject(RAX, bool_true);
   __ ret();
   return true;
 }
 
 #undef __
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64