Fixes a couple problems with GC of unoptimized code.

runtime/vm/flow_graph_compiler_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/flow_graph_compiler.h"
 
 #include "vm/ast_printer.h"
@@ skipping 43 matching lines @@
   Environment* current = deopt_env_;
 
   // Emit all kMaterializeObject instructions describing objects to be
   // materialized on the deoptimization as a prefix to the deoptimization info.
   EmitMaterializations(deopt_env_, builder);
 
   // The real frame starts here.
   builder->MarkFrameStart();
 
   // Current PP, FP, and PC.
-  builder->AddPp(current->function(), slot_ix++);
+  builder->AddPp(current->code(), slot_ix++);
   builder->AddCallerFp(slot_ix++);
-  builder->AddReturnAddress(current->function(), deopt_id(), slot_ix++);
+  builder->AddReturnAddress(current->code(), deopt_id(), slot_ix++);
 
-  // Callee's PC marker is not used anymore. Pass Function::null() to set to 0.
-  builder->AddPcMarker(Function::Handle(), slot_ix++);
+  // Callee's PC marker is not used anymore. Pass Code::null() to set to 0.
+  builder->AddPcMarker(Code::Handle(), slot_ix++);
 
   // Emit all values that are needed for materialization as a part of the
   // expression stack for the bottom-most frame. This guarantees that GC
   // will be able to find them during materialization.
   slot_ix = builder->EmitMaterializationArguments(slot_ix);
 
   // For the innermost environment, set outgoing arguments and the locals.
   for (intptr_t i = current->Length() - 1;
        i >= current->fixed_parameter_count();
        i--) {
     builder->AddCopy(current->ValueAt(i), current->LocationAt(i), slot_ix++);
   }
 
   Environment* previous = current;
   current = current->outer();
   while (current != NULL) {
     // PP, FP, and PC.
-    builder->AddPp(current->function(), slot_ix++);
+    builder->AddPp(current->code(), slot_ix++);
     builder->AddCallerFp(slot_ix++);
 
     // For any outer environment the deopt id is that of the call instruction
     // which is recorded in the outer environment.
-    builder->AddReturnAddress(current->function(),
+    builder->AddReturnAddress(current->code(),
                               Isolate::ToDeoptAfter(current->deopt_id()),
                               slot_ix++);
 
     // PC marker.
-    builder->AddPcMarker(previous->function(), slot_ix++);
+    builder->AddPcMarker(previous->code(), slot_ix++);
 
     // The values of outgoing arguments can be changed from the inlined call so
     // we must read them from the previous environment.
     for (intptr_t i = previous->fixed_parameter_count() - 1; i >= 0; i--) {
       builder->AddCopy(previous->ValueAt(i),
                        previous->LocationAt(i),
                        slot_ix++);
     }
 
     // Set the locals, note that outgoing arguments are not in the environment.
@@ skipping 11 matching lines @@
   }
   // The previous pointer is now the outermost environment.
   ASSERT(previous != NULL);
 
   // For the outermost environment, set caller PC, caller PP, and caller FP.
   builder->AddCallerPp(slot_ix++);
   builder->AddCallerFp(slot_ix++);
   builder->AddCallerPc(slot_ix++);
 
   // PC marker.
-  builder->AddPcMarker(previous->function(), slot_ix++);
+  builder->AddPcMarker(previous->code(), slot_ix++);
 
   // For the outermost environment, set the incoming arguments.
   for (intptr_t i = previous->fixed_parameter_count() - 1; i >= 0; i--) {
     builder->AddCopy(previous->ValueAt(i), previous->LocationAt(i), slot_ix++);
   }
 
   const DeoptInfo& deopt_info =
       DeoptInfo::Handle(builder->CreateDeoptInfo(deopt_table));
   return deopt_info.raw();
 }
@@ skipping 1256 matching lines @@
   __ sll(T1, T3, 2);
   __ addu(T1, T2, T1);
   __ lw(T0, FieldAddress(T1, base + kWordSize));
   __ lw(T1, FieldAddress(T0, Function::code_offset()));
   if (FLAG_collect_code) {
     // If we are collecting code, the code object may be null.
     Label is_compiled;
     __ BranchNotEqual(T1, reinterpret_cast<int32_t>(Object::null()),
                       &is_compiled);
     __ BranchLink(&StubCode::CompileFunctionRuntimeCallLabel());
+    AddCurrentDescriptor(PcDescriptors::kRuntimeCall,
+                         Isolate::kNoDeoptId,
+                         token_pos);
+    RecordSafepoint(locs);
     __ lw(T1, FieldAddress(T0, Function::code_offset()));
     __ Bind(&is_compiled);
   }
   __ lw(T0, FieldAddress(T1, Code::instructions_offset()));
   __ LoadObject(S5, ic_data);
   __ LoadObject(S4, arguments_descriptor);
   __ AddImmediate(T0, Instructions::HeaderSize() - kHeapObjectTag);
   __ jalr(T0);
   AddCurrentDescriptor(PcDescriptors::kOther, Isolate::kNoDeoptId, token_pos);
   RecordSafepoint(locs);
@@ skipping 509 matching lines @@
   __ AddImmediate(SP, kDoubleSize);
 }
 
 
 #undef __
 
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS