Don't ignore the actual input representation in UnaryMathOperations

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
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@@ skipping 3050 matching lines @@
 HType HBitNot::CalculateInferredType() {
   return HType::TaggedNumber();
 }
 
 
 HType HUnaryMathOperation::CalculateInferredType() {
   return HType::TaggedNumber();
 }
 
 
+Representation HUnaryMathOperation::RepresentationFromInputs() {
+  // Determine the worst case of observed input representations and
+  // the currently assumed output representation.
+  Representation rep = representation();
+  rep = rep.generalize(observed_input_representation(1));

[Jakob Kummerow, 2013/06/07 08:44:45]

HUnaryMathOperation doesn't have observed input representations (because these
ops are just calls in full codegen, and call ICs don't observe types of the
call's arguments), it just falls back to the HValue default implementation which
returns None.

[Toon Verwaest, 2013/06/07 09:09:52]

Done.

+  // If any of the actual input representation is more general than what we
+  // have so far but not Tagged, use that representation instead.
+  Representation input_rep = value()->representation();
+  if (!input_rep.IsTagged()) rep = rep.generalize(input_rep);
+  return rep;
+}
+
+
 HType HStringCharFromCode::CalculateInferredType() {
   return HType::String();
 }
 
 
 HType HAllocate::CalculateInferredType() {
   return type_;
 }
 
 
@@ skipping 723 matching lines @@
     case kBackingStore:
       if (!name_.is_null()) stream->Add(*String::cast(*name_)->ToCString());
       stream->Add("[backing-store]");
       break;
   }
 
   stream->Add("@%d", offset());
 }
 
 } }  // namespace v8::internal