Remove isolate pointer from context objects.

runtime/vm/intermediate_language_mips.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_MIPS.
 #if defined(TARGET_ARCH_MIPS)
 
 #include "vm/intermediate_language.h"
 
 #include "vm/dart_entry.h"
@@ skipping 2373 matching lines @@
   __ TryAllocateArray(kContextCid, instance_size, slow_path->entry_label(),
                       result,  // instance
                       temp0,
                       temp1,
                       temp2);
 
   // Setup up number of context variables field.
   __ LoadImmediate(temp0, num_context_variables());
   __ sw(temp0, FieldAddress(result, Context::num_variables_offset()));
 
-  // Setup isolate field.
-  __ lw(temp0, FieldAddress(CTX, Context::isolate_offset()));
-  __ sw(temp0, FieldAddress(result, Context::isolate_offset()));
-
   __ Bind(slow_path->exit_label());
 }
 
 
 LocationSummary* AllocateContextInstr::MakeLocationSummary(Isolate* isolate,
                                                            bool opt) const {
   const intptr_t kNumInputs = 0;
   const intptr_t kNumTemps = 1;
   LocationSummary* locs = new(isolate) LocationSummary(
       isolate, kNumInputs, kNumTemps, LocationSummary::kCall);
@@ skipping 2540 matching lines @@
   compiler->GenerateCall(token_pos(), &label, stub_kind_, locs());
 #if defined(DEBUG)
   __ LoadImmediate(S4, kInvalidObjectPointer);
   __ LoadImmediate(S5, kInvalidObjectPointer);
 #endif
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS