This is a little experiment to move Failure to a superclass above Object...

src/arm/stub-cache-arm.cc

Index: src/arm/stub-cache-arm.cc
===================================================================
--- src/arm/stub-cache-arm.cc	(revision 5559)
+++ src/arm/stub-cache-arm.cc	(working copy)
@@ -838,9 +838,11 @@
                                          GlobalObject* global,
                                          String* name,
                                          Register scratch,
+  Object* probe;
+  { TryAllocation t = global->EnsurePropertyCell(name);
+    if (!t->ToObject(&probe)) return t;
+  }
                                          Label* miss) {
-  Object* probe = global->EnsurePropertyCell(name);
-  if (probe->IsFailure()) return probe;
   JSGlobalPropertyCell* cell = JSGlobalPropertyCell::cast(probe);
   ASSERT(cell->value()->IsTheHole());
   __ mov(scratch, Operand(Handle<Object>(cell)));
@@ -1281,9 +1283,12 @@
 }
 
 
+  Object* obj;
+  { TryAllocation t =
+        StubCache::ComputeCallMiss(arguments().immediate(), kind_);
+    if (!t->ToObject(&obj)) return t;
+  }
 Object* CallStubCompiler::GenerateMissBranch() {
-  Object* obj = StubCache::ComputeCallMiss(arguments().immediate(), kind_);
-  if (obj->IsFailure()) return obj;
   __ Jump(Handle<Code>(Code::cast(obj)), RelocInfo::CODE_TARGET);
   return obj;
 }
@@ -1316,9 +1321,11 @@
   GenerateCallFunction(masm(), object, arguments(), &miss);
 
   // Handle call cache miss.
+  Object* obj;
+  { TryAllocation t = GenerateMissBranch();
+    if (!t->ToObject(&obj)) return t;
+  }
   __ bind(&miss);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
 
   // Return the generated code.
   return GetCode(FIELD, name);
@@ -1360,9 +1367,11 @@
                                1);
 
   // Handle call cache miss.
+  Object* obj;
+  { TryAllocation t = GenerateMissBranch();
+    if (!t->ToObject(&obj)) return t;
+  }
   __ bind(&miss);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
 
   // Return the generated code.
   return GetCode(function);
@@ -1404,9 +1413,11 @@
                                1);
 
   // Handle call cache miss.
+  Object* obj;
+  { TryAllocation t = GenerateMissBranch();
+    if (!t->ToObject(&obj)) return t;
+  }
   __ bind(&miss);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
 
   // Return the generated code.
   return GetCode(function);
@@ -1476,9 +1487,11 @@
   __ Drop(argc + 1);
   __ Ret();
 
+  Object* obj;
+  { TryAllocation t = GenerateMissBranch();
+    if (!t->ToObject(&obj)) return t;
+  }
   __ bind(&miss);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
 
   // Return the generated code.
   return GetCode(function);
@@ -1550,9 +1563,11 @@
   __ Drop(argc + 1);
   __ Ret();
 
+  Object* obj;
+  { TryAllocation t = GenerateMissBranch();
+    if (!t->ToObject(&obj)) return t;
+  }
   __ bind(&miss);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
 
   // Return the generated code.
   return GetCode(function);
@@ -1624,9 +1639,11 @@
   __ InvokeFunction(function, arguments(), JUMP_FUNCTION);
 
   __ bind(&miss);
+  Object* obj;
+  { TryAllocation t = GenerateMissBranch();
+    if (!t->ToObject(&obj)) return t;
+  }
   // r2: function name.
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
 
   // Return the generated code.
   return (cell == NULL) ? GetCode(function) : GetCode(NORMAL, name);
@@ -1736,9 +1753,11 @@
   __ InvokeFunction(function, arguments(), JUMP_FUNCTION);
 
   __ bind(&miss);
+  Object* obj;
+  { TryAllocation t = GenerateMissBranch();
+    if (!t->ToObject(&obj)) return t;
+  }
   // r2: function name.
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
 
   // Return the generated code.
   return (cell == NULL) ? GetCode(function) : GetCode(NORMAL, name);
@@ -1890,9 +1909,11 @@
     FreeSpaceForFastApiCall(masm());
   }
 
+  Object* obj;
+  { TryAllocation t = GenerateMissBranch();
+    if (!t->ToObject(&obj)) return t;
+  }
   __ bind(&miss_in_smi_check);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
 
   // Return the generated code.
   return GetCode(function);
@@ -1940,9 +1961,11 @@
   GenerateCallFunction(masm(), object, arguments(), &miss);
 
   // Handle call cache miss.
+  Object* obj;
+  { TryAllocation t = GenerateMissBranch();
+    if (!t->ToObject(&obj)) return t;
+  }
   __ bind(&miss);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
 
   // Return the generated code.
   return GetCode(INTERCEPTOR, name);
@@ -1999,9 +2022,11 @@
 
   // Handle call cache miss.
   __ bind(&miss);
+  Object* obj;
+  { TryAllocation t = GenerateMissBranch();
+    if (!t->ToObject(&obj)) return t;
+  }
   __ IncrementCounter(&Counters::call_global_inline_miss, 1, r1, r3);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
 
   // Return the generated code.
   return GetCode(NORMAL, name);