DBC: Add missing deopt info after stack overflow checks.

runtime/vm/deopt_instructions.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/deopt_instructions.h"
 
 #include "vm/assembler.h"
 #include "vm/code_patcher.h"
 #include "vm/compiler.h"
+#include "vm/disassembler.h"
 #include "vm/intermediate_language.h"
 #include "vm/locations.h"
 #include "vm/parser.h"
 #include "vm/stack_frame.h"
 #include "vm/thread.h"
 #include "vm/timeline.h"
 
 namespace dart {
 
 DEFINE_FLAG(bool, compress_deopt_info, true,
@@ skipping 25 matching lines @@
       deopt_flags_(0),
       thread_(Thread::Current()),
       deopt_start_micros_(0),
       deferred_slots_(NULL),
       deferred_objects_count_(0),
       deferred_objects_(NULL),
       is_lazy_deopt_(is_lazy_deopt),
       deoptimizing_code_(deoptimizing_code) {
   const TypedData& deopt_info = TypedData::Handle(
       code.GetDeoptInfoAtPc(frame->pc(), &deopt_reason_, &deopt_flags_));
+#if defined(DEBUG)
+  if (deopt_info.IsNull()) {
+    OS::PrintErr("Missing deopt info for pc %" Px "\n", frame->pc());
+    DisassembleToStdout formatter;
+    code.Disassemble(&formatter);
+  }
+#endif
   ASSERT(!deopt_info.IsNull());
   deopt_info_ = deopt_info.raw();
 
   const Function& function = Function::Handle(code.function());
 
   // Do not include incoming arguments if there are optional arguments
   // (they are copied into local space at method entry).
   num_args_ =
       function.HasOptionalParameters() ? 0 : function.num_fixed_parameters();
 
@@ skipping 1281 matching lines @@
                           Smi* offset,
                           TypedData* info,
                           Smi* reason) {
   intptr_t i = index * kEntrySize;
   *offset ^= table.At(i);
   *info ^= table.At(i + 1);
   *reason ^= table.At(i + 2);
 }
 
 }  // namespace dart