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

runtime/vm/intermediate_language_arm.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_ARM.
 #if defined(TARGET_ARCH_ARM)
 
 #include "vm/intermediate_language.h"
 
 #include "vm/cpu.h"
@@ skipping 2298 matching lines @@
                                    Label* done) {
   const int kInlineArraySize = 12;  // Same as kInlineInstanceSize.
   const Register kLengthReg = R2;
   const Register kElemTypeReg = R1;
   const intptr_t instance_size = Array::InstanceSize(num_elements);
 
   __ TryAllocateArray(kArrayCid, instance_size, slow_path,
                       R0,  // instance
                       R3,  // end address
                       R6,
-                      R8);
+                      R9);
   // R0: new object start as a tagged pointer.
   // R3: new object end address.
 
   // Store the type argument field.
   __ InitializeFieldNoBarrier(R0,
                               FieldAddress(R0, Array::type_arguments_offset()),
                               kElemTypeReg);
 
   // Set the length field.
   __ InitializeFieldNoBarrier(R0,
                               FieldAddress(R0, Array::length_offset()),
                               kLengthReg);
 
   // Initialize all array elements to raw_null.
   // R0: new object start as a tagged pointer.
   // R3: new object end address.
-  // R8: iterator which initially points to the start of the variable
+  // R9: iterator which initially points to the start of the variable
   // data area to be initialized.
   // R6: null
   if (num_elements > 0) {
     const intptr_t array_size = instance_size - sizeof(RawArray);
     __ LoadImmediate(R6, reinterpret_cast<intptr_t>(Object::null()));
     if (num_elements >= 2) {
       __ mov(R7, Operand(R6));
     } else {
 #if defined(DEBUG)
       // Clobber R7 with an invalid pointer.
       __ LoadImmediate(R7, 0x1);
 #endif  // DEBUG
     }
-    __ AddImmediate(R8, R0, sizeof(RawArray) - kHeapObjectTag);
+    __ AddImmediate(R9, R0, sizeof(RawArray) - kHeapObjectTag);
     if (array_size < (kInlineArraySize * kWordSize)) {
-      __ InitializeFieldsNoBarrierUnrolled(R0, R8, 0, num_elements * kWordSize,
+      __ InitializeFieldsNoBarrierUnrolled(R0, R9, 0, num_elements * kWordSize,
                                            R6, R7);
     } else {
-      __ InitializeFieldsNoBarrier(R0, R8, R3, R6, R7);
+      __ InitializeFieldsNoBarrier(R0, R9, R3, R6, R7);
     }
   }
   __ b(done);
 }
 
 
 void CreateArrayInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   const Register kLengthReg = R2;
   const Register kElemTypeReg = R1;
   const Register kResultReg = R0;
@@ skipping 4517 matching lines @@
                                 1,
                                 locs());
   __ Drop(1);
   __ Pop(result);
 }
 
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM