Add flag trap_on_stub_deopt. We want to be able to trap on hydrogen stub bailouts.

src/arm/lithium-codegen-arm.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 787 matching lines @@
 
   ASSERT(FLAG_deopt_every_n_times < 2);  // Other values not supported on ARM.
   if (FLAG_deopt_every_n_times == 1 &&
       !info()->IsStub() &&
       info()->opt_count() == id) {
     ASSERT(frame_is_built_);
     __ Call(entry, RelocInfo::RUNTIME_ENTRY);
     return;
   }
 
-  if (FLAG_trap_on_deopt && info()->IsOptimizing()) {
+  if ((FLAG_trap_on_deopt && info()->IsOptimizing()) ||
+      (FLAG_trap_on_stub_deopt && info()->IsStub())) {

[Sven Panne, 2013/08/08 06:31:28]

To remove the copy-n-paste, please make this a predicate on CompilationInfo:

   if (info()->ShouldTrapOnDeopt()) {
      ...
   }

     __ stop("trap_on_deopt", cc);
   }
 
   ASSERT(info()->IsStub() || frame_is_built_);
   if (cc == al && frame_is_built_) {
     __ Call(entry, RelocInfo::RUNTIME_ENTRY);
   } else {
     // We often have several deopts to the same entry, reuse the last
     // jump entry if this is the case.
     if (deopt_jump_table_.is_empty() ||
@@ skipping 5037 matching lines @@
   __ sub(scratch, result, Operand::PointerOffsetFromSmiKey(index));
   __ ldr(result, FieldMemOperand(scratch,
                                  FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal