Load predefined symbols address via Thread.

runtime/vm/intermediate_language_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/intermediate_language.h"
 
 #include "vm/dart_entry.h"
@@ skipping 832 matching lines @@
                                Location::RequiresRegister(),
                                LocationSummary::kNoCall);
 }
 
 
 void StringFromCharCodeInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   ASSERT(compiler->is_optimizing());
   const Register char_code = locs()->in(0).reg();
   const Register result = locs()->out(0).reg();
 
-  ExternalLabel label(reinterpret_cast<uword>(Symbols::PredefinedAddress()));
-  __ LoadExternalLabel(result, &label);
+  __ ldr(result, Address(THR, Thread::predefined_symbols_address_offset()));
   __ AddImmediate(
       result, result, Symbols::kNullCharCodeSymbolOffset * kWordSize);
   __ SmiUntag(TMP, char_code);  // Untag to use scaled adress mode.
   __ ldr(result, Address(result, TMP, UXTX, Address::Scaled));
 }
 
 
 LocationSummary* StringToCharCodeInstr::MakeLocationSummary(Zone* zone,
                                                             bool opt) const {
   const intptr_t kNumInputs = 1;
@@ skipping 4758 matching lines @@
                                 1,
                                 locs());
   __ Drop(1);
   __ Pop(result);
 }
 
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM64