Eliminate 99% of allocated ExceptionHandler objects

runtime/vm/stack_frame.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/stack_frame.h"
 
 #include "vm/assembler.h"
 #include "vm/deopt_instructions.h"
 #include "vm/isolate.h"
 #include "vm/object.h"
@@ skipping 200 matching lines @@
   REUSABLE_CODE_HANDLESCOPE(isolate);
   Code& code = reused_code_handle.Handle();
   code = LookupDartCode();
   if (code.IsNull()) {
     return false;  // Stub frames do not have exception handlers.
   }
 
   REUSABLE_EXCEPTION_HANDLERS_HANDLESCOPE(isolate);
   ExceptionHandlers& handlers = reused_exception_handlers_handle.Handle();
   handlers = code.exception_handlers();
-  if (handlers.Length() == 0) {
+  if (handlers.num_entries() == 0) {
     return false;
   }
 
   // Find pc descriptor for the current pc.
   REUSABLE_PC_DESCRIPTORS_HANDLESCOPE(isolate);
   PcDescriptors& descriptors = reused_pc_descriptors_handle.Handle();
   descriptors = code.pc_descriptors();
   PcDescriptors::Iterator iter(descriptors, RawPcDescriptors::kAnyKind);
   while (iter.MoveNext()) {
     const intptr_t current_try_index = iter.TryIndex();
@@ skipping 252 matching lines @@
     if (deopt_instr->kind() == DeoptInstr::kCallerFp) {
       return (index - num_materializations_);
     }
   }
   UNREACHABLE();
   return 0;
 }
 
 
 }  // namespace dart