Fix for issue 7757

runtime/vm/deopt_instructions.cc

Index: runtime/vm/deopt_instructions.cc
===================================================================
--- runtime/vm/deopt_instructions.cc	(revision 16999)
+++ runtime/vm/deopt_instructions.cc	(working copy)
@@ -209,6 +209,13 @@
     *to_addr = continue_at_pc;
   }
 
+  static void GetEncodedValues(intptr_t from_index,
+                               intptr_t* object_table_index,
+                               intptr_t* deopt_id) {
+    *object_table_index = ObjectTableIndex::decode(from_index);
+    *deopt_id = DeoptId::decode(from_index);
+  }
+
  private:
   static const intptr_t kFieldWidth = kBitsPerWord / 2;
   class ObjectTableIndex : public BitField<intptr_t, 0, kFieldWidth> { };
@@ -563,6 +570,22 @@
 }
 
 
+uword DeoptInstr::GetRetAfterAddress(intptr_t from_index,
+                                     const Array& object_table,
+                                     Function* func) {
+  ASSERT(!object_table.IsNull());
+  ASSERT(func != NULL);
+  intptr_t object_table_index;
+  intptr_t deopt_id;
+  DeoptRetAfterAddressInstr::GetEncodedValues(from_index,
+                                              &object_table_index,
+                                              &deopt_id);
+  *func ^= object_table.At(object_table_index);
+  const Code& code = Code::Handle(func->unoptimized_code());
+  return code.GetDeoptAfterPcAtDeoptId(deopt_id);
+}
+
+
 DeoptInstr* DeoptInstr::Create(intptr_t kind_as_int, intptr_t from_index) {
   Kind kind = static_cast<Kind>(kind_as_int);
   switch (kind) {