Remove remaining uses of null's absolute address from non-IA32.

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"
 #include "vm/flow_graph.h"
 #include "vm/flow_graph_compiler.h"
 #include "vm/flow_graph_range_analysis.h"
 #include "vm/locations.h"
 #include "vm/object_store.h"
 #include "vm/parser.h"
 #include "vm/simulator.h"
 #include "vm/stack_frame.h"
 #include "vm/stub_code.h"
 #include "vm/symbols.h"
 
 #define __ compiler->assembler()->
 
 namespace dart {
 
+DECLARE_FLAG(bool, allow_absolute_addresses);
 DECLARE_FLAG(bool, emit_edge_counters);
 DECLARE_FLAG(int, optimization_counter_threshold);
 DECLARE_FLAG(bool, use_osr);
 
 // Generic summary for call instructions that have all arguments pushed
 // on the stack and return the result in a fixed register V0.
 LocationSummary* Instruction::MakeCallSummary(Zone* zone) {
   LocationSummary* result = new(zone) LocationSummary(
       zone, 0, 0, LocationSummary::kCall);
   result->set_out(0, Location::RegisterLocation(V0));
@@ skipping 1694 matching lines @@
         __ LoadImmediate(TMP, field_cid);
         __ subu(CMPRES1, value_cid_reg, TMP);
       }
 
       if (field().is_nullable() && (field_cid != kNullCid)) {
         __ beq(CMPRES1, ZR, &ok);
         if (field_cid != kSmiCid) {
           __ LoadImmediate(TMP, kNullCid);
           __ subu(CMPRES1, value_cid_reg, TMP);
         } else {
-          __ LoadImmediate(TMP, reinterpret_cast<int32_t>(Object::null()));
+          __ LoadObject(TMP, Object::null_object());
           __ subu(CMPRES1, value_reg, TMP);
         }
       }
 
       __ bne(CMPRES1, ZR, fail);
     } else {
       // Both value's and field's class id is known.
       ASSERT((value_cid != field_cid) && (value_cid != nullability));
       __ b(fail);
     }
@@ skipping 446 matching lines @@
                               kLengthReg);
 
   // Initialize all array elements to raw_null.
   // V0: new object start as a tagged pointer.
   // T1: new object end address.
   // T2: iterator which initially points to the start of the variable
   // data area to be initialized.
   // T7: null.
   if (num_elements > 0) {
     const intptr_t array_size = instance_size - sizeof(RawArray);
-    __ LoadImmediate(T7, reinterpret_cast<int32_t>(Object::null()));
+    __ LoadObject(T7, Object::null_object());
     __ AddImmediate(T2, V0, sizeof(RawArray) - kHeapObjectTag);
     if (array_size < (kInlineArraySize * kWordSize)) {
       intptr_t current_offset = 0;
       while (current_offset < array_size) {
         __ sw(T7, Address(T2, current_offset));
         current_offset += kWordSize;
       }
     } else {
       Label init_loop;
       __ Bind(&init_loop);
@@ skipping 490 matching lines @@
  public:
   explicit CheckStackOverflowSlowPath(CheckStackOverflowInstr* instruction)
       : instruction_(instruction) { }
 
   virtual void EmitNativeCode(FlowGraphCompiler* compiler) {
     if (FLAG_use_osr && osr_entry_label()->IsLinked()) {
       uword flags_address = Isolate::Current()->stack_overflow_flags_address();
       Register value = instruction_->locs()->temp(0).reg();
       __ Comment("CheckStackOverflowSlowPathOsr");
       __ Bind(osr_entry_label());
+      ASSERT(FLAG_allow_absolute_addresses);
       __ LoadImmediate(TMP, flags_address);
       __ LoadImmediate(value, Isolate::kOsrRequest);
       __ sw(value, Address(TMP));
     }
     __ Comment("CheckStackOverflowSlowPath");
     __ Bind(entry_label());
     compiler->SaveLiveRegisters(instruction_->locs());
     // pending_deoptimization_env_ is needed to generate a runtime call that
     // may throw an exception.
     ASSERT(compiler->pending_deoptimization_env_ == NULL);
@@ skipping 25 matching lines @@
   CheckStackOverflowInstr* instruction_;
   Label osr_entry_label_;
 };
 
 
 void CheckStackOverflowInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   __ Comment("CheckStackOverflowInstr");
   CheckStackOverflowSlowPath* slow_path = new CheckStackOverflowSlowPath(this);
   compiler->AddSlowPathCode(slow_path);
 
-  if (compiler->is_optimizing()) {
+  if (compiler->is_optimizing() && FLAG_allow_absolute_addresses) {
     __ LoadImmediate(TMP, Isolate::Current()->stack_limit_address());
     __ lw(CMPRES1, Address(TMP));
   } else {
     __ LoadIsolate(TMP);
     __ lw(CMPRES1, Address(TMP, Isolate::stack_limit_offset()));
   }
   __ BranchUnsignedLessEqual(SP, CMPRES1, slow_path->entry_label());
   if (compiler->CanOSRFunction() && in_loop()) {
     Register temp = locs()->temp(0).reg();
     // In unoptimized code check the usage counter to trigger OSR at loop
@@ skipping 2827 matching lines @@
                                 1,
                                 locs());
   __ lw(result, Address(SP, 1 * kWordSize));
   __ addiu(SP, SP, Immediate(2 * kWordSize));
 }
 
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS