Cache current thread in a reserved register and use it in LoadIsolate

runtime/vm/assembler_arm_test.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"
 #if defined(TARGET_ARCH_ARM)
 
 #include "vm/assembler.h"
 #include "vm/cpu.h"
 #include "vm/os.h"
@@ skipping 3913 matching lines @@
     EXPECT_FLOAT_EQ(2.0, res, 0.0001f);
   }
 }
 
 
 // Called from assembler_test.cc.
 // LR: return address.
 // R0: context.
 // R1: value.
 // R2: growable array.
+// R3: current thread.
 ASSEMBLER_TEST_GENERATE(StoreIntoObject, assembler) {
-  __ PushList((1 << CTX) | (1 << LR));
+  __ PushList((1 << CTX) | (1 << LR) | (1 << THR));
   __ mov(CTX, Operand(R0));
+  __ mov(THR, Operand(R3));
   __ StoreIntoObject(R2,
                      FieldAddress(R2, GrowableObjectArray::data_offset()),
                      R1);
-  __ PopList((1 << CTX) | (1 << LR));
+  __ PopList((1 << CTX) | (1 << LR) | (1 << THR));
   __ Ret();
 }
 
 
 ASSEMBLER_TEST_GENERATE(ComputeRange, assembler) {
   Label miss, done;
   __ mov(R1, Operand(R0));
   __ ComputeRange(R0, R1, R2, &miss);
   __ b(&done);
 
@@ skipping 38 matching lines @@
   EXPECT_EQ(ICData::kInt64RangeBit, RANGE_OF(Integer::New(kMinInt64)));
 
   EXPECT_EQ(-1, RANGE_OF(Bool::True().raw()));
 
 #undef RANGE_OF
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM