Deoptimization can occur at Dart calls (includes native calls to C) but not at runtime calls. This …

runtime/vm/flow_graph_compiler.cc

 // Copyright (c) 2012, 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_XXX.
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/dart_entry.h"
 #include "vm/debugger.h"
@@ skipping 220 matching lines @@
                                        token_pos,
                                        CurrentTryIndex());
 }
 
 
 void FlowGraphCompiler::AddDeoptIndexAtCall(intptr_t deopt_id,
                                             intptr_t token_pos) {
   // TODO(srdjan): Temporary use deopt stubs to maintain deopt-indexes.
   // kDeoptAtCall will not emit code, but will only generate deoptimization
   // information.
+  ASSERT(is_optimizing());
   const intptr_t deopt_index = deopt_stubs_.length();
   AddDeoptStub(deopt_id, kDeoptAtCall);
-  pc_descriptors_list()->AddDescriptor(PcDescriptors::kDeoptIndex,
-                                       assembler()->CodeSize(),
+  pc_descriptors_list()->AddDeoptIndex(assembler()->CodeSize(),
                                        deopt_id,
-                                       token_pos,
+                                       kDeoptAtCall,
                                        deopt_index);
 }
 
 
 void FlowGraphCompiler::RecordSafepoint(LocationSummary* locs) {
   if (is_optimizing()) {
     BitmapBuilder* bitmap = locs->stack_bitmap();
     ASSERT(bitmap != NULL);
     ASSERT(bitmap->Length() <= StackSize());
     // Pad the bitmap out to describe all the spill slots.
@@ skipping 527 matching lines @@
       return;
     }
   }
 
   // This move is not blocked.
   EmitMove(index);
 }
 
 
 }  // namespace dart