Improve smi support in crankshaft

src/hydrogen.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 2862 matching lines @@
     }
   }
 
   // Simplify constant phi inputs where possible.
   // This step uses kTruncatingToInt32 flags of phis.
   for (int i = 0; i < phi_count; ++i) {
     phi_list->at(i)->SimplifyConstantInputs();
   }
 
   // Use the phi reachability information from step 2 to
-  // push information about values which can't be converted to integer
-  // without deoptimization through the phi use-def chains, avoiding
-  // unnecessary deoptimizations later.
-  for (int i = 0; i < phi_count; ++i) {
-    HPhi* phi = phi_list->at(i);
-    bool cti = phi->AllOperandsConvertibleToInteger();
-    if (cti) continue;
-
-    for (BitVector::Iterator it(connected_phis.at(i));
-         !it.Done();
-         it.Advance()) {
-      HPhi* phi = phi_list->at(it.Current());
-      phi->set_is_convertible_to_integer(false);
-    }
-  }
-
-  // Use the phi reachability information from step 2 to
   // sum up the non-phi use counts of all connected phis.
   for (int i = 0; i < phi_count; ++i) {
     HPhi* phi = phi_list->at(i);
     for (BitVector::Iterator it(connected_phis.at(i));
          !it.Done();
          it.Advance()) {
       int index = it.Current();
       HPhi* it_use = phi_list->at(index);
       if (index != i) phi->AddNonPhiUsesFrom(it_use);  // Don't count twice.
     }
@@ skipping 8588 matching lines @@
     }
   }
 
 #ifdef DEBUG
   if (graph_ != NULL) graph_->Verify(false);  // No full verify.
   if (allocator_ != NULL) allocator_->Verify();
 #endif
 }
 
 } }  // namespace v8::internal