Use (more) xor on FP register to load it with 0.0.

runtime/vm/flow_graph_compiler_arm64.cc

 // Copyright (c) 2014, 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_ARM64.
 #if defined(TARGET_ARCH_ARM64)
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/ast_printer.h"
@@ skipping 1567 matching lines @@
       __ LoadQFromOffset(VTMP, FP, source_offset, PP);
       __ StoreQToOffset(VTMP, FP, dest_offset, PP);
     }
   } else {
     ASSERT(source.IsConstant());
     const Object& constant = source.constant();
     if (destination.IsRegister()) {
       __ LoadObject(destination.reg(), constant, PP);
     } else if (destination.IsFpuRegister()) {
       const VRegister dst = destination.fpu_reg();
-      __ LoadObject(TMP, constant, PP);
-      __ LoadDFieldFromOffset(dst, TMP, Double::value_offset(), PP);
+      if (Utils::DoublesBitEqual(Double::Cast(constant).value(), 0.0)) {
+        __ veor(dst, dst, dst);
+      } else {
+        __ LoadObject(TMP, constant, PP);
+        __ LoadDFieldFromOffset(dst, TMP, Double::value_offset(), PP);
+      }
     } else if (destination.IsDoubleStackSlot()) {
+      if (Utils::DoublesBitEqual(Double::Cast(constant).value(), 0.0)) {
+        __ veor(VTMP, VTMP, VTMP);
+      } else {
+        __ LoadObject(TMP, constant, PP);
+        __ LoadDFieldFromOffset(VTMP, TMP, Double::value_offset(), PP);
+      }
       const intptr_t dest_offset = destination.ToStackSlotOffset();
-      __ LoadObject(TMP, constant, PP);
-      __ LoadDFieldFromOffset(VTMP, TMP, Double::value_offset(), PP);
       __ StoreDToOffset(VTMP, FP, dest_offset, PP);
     } else {
       ASSERT(destination.IsStackSlot());
       const intptr_t dest_offset = destination.ToStackSlotOffset();
       __ LoadObject(TMP, constant, PP);
       __ StoreToOffset(TMP, FP, dest_offset, PP);
     }
   }
 
   move->Eliminate();
@@ skipping 131 matching lines @@
 void ParallelMoveResolver::RestoreFpuScratch(FpuRegister reg) {
   UNIMPLEMENTED();
 }
 
 
 #undef __
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM64