Removed useless Canonicalize implementations subsumed by dead code elimination.

src/hydrogen-instructions.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 841 matching lines @@
 }
 
 
 void HLoadFieldByIndex::PrintDataTo(StringStream* stream) {
   object()->PrintNameTo(stream);
   stream->Add(" ");
   index()->PrintNameTo(stream);
 }
 
 
-HValue* HConstant::Canonicalize() {
-  return HasNoUses() ? NULL : this;
-}
-
-
-HValue* HTypeof::Canonicalize() {
-  return HasNoUses() ? NULL : this;
-}
-
-
 HValue* HBitwise::Canonicalize() {
   if (!representation().IsInteger32()) return this;
   // If x is an int32, then x & -1 == x, x | 0 == x and x ^ 0 == x.
   int32_t nop_constant = (op() == Token::BIT_AND) ? -1 : 0;
   if (left()->IsConstant() &&
       HConstant::cast(left())->HasInteger32Value() &&
       HConstant::cast(left())->Integer32Value() == nop_constant &&
       !right()->CheckFlag(kUint32)) {
     return right();
   }
@@ skipping 1653 matching lines @@
 
 
 void HCheckFunction::Verify() {
   HInstruction::Verify();
   ASSERT(HasNoUses());
 }
 
 #endif
 
 } }  // namespace v8::internal