Faster to number conversion

src/hydrogen-instructions.h

 // 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 389 matching lines @@
   bool IsHeapNumber() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kHeapNumber) == kHeapNumber);
   }
 
   bool IsString() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kString) == kString);
   }
 
+  bool IsNoString() const {

[Toon Verwaest, 2013/07/22 08:30:21]

Can we name this IsNonString, in line with IsNonPrimitive?

[oliv, 2013/07/22 13:56:43]

Done.

+    if (IsTaggedPrimitive() || IsSmi() || IsHeapNumber() ||

[Sven Panne, 2013/07/22 07:06:36]

o_O o_O o_O

return IsTaggedPrimitive() || IsSmi() || IsHeapNumber() || IsBoolean() ||
IsJSArray();

[oliv, 2013/07/22 07:34:30]

lol, that's embarrassing

+        IsBoolean() || IsJSArray()) {
+      return true;
+    }
+    return false;
+  }
+
   bool IsBoolean() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kBoolean) == kBoolean);
   }
 
   bool IsNonPrimitive() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kNonPrimitive) == kNonPrimitive);
   }
 
@@ skipping 2923 matching lines @@
     if (HasInteger32Value()) return Representation::Integer32();
     if (HasNumberValue()) return Representation::Double();
     return Representation::Tagged();
   }
 
   virtual bool EmitAtUses();
   virtual void PrintDataTo(StringStream* stream);
   virtual HType CalculateInferredType();
   bool IsInteger() { return handle()->IsSmi(); }
   HConstant* CopyToRepresentation(Representation r, Zone* zone) const;
-  HConstant* CopyToTruncatedInt32(Zone* zone) const;
+  HConstant* CopyToTruncatedInt32(Zone* zone);

[Toon Verwaest, 2013/07/22 08:30:21]

I guess you tried hard to keep this const? I'd prefer to keep it; but if it's
too hard... meh :)

[oliv, 2013/07/22 13:56:43]

the problem is deferred handle dereference in TruncateToNumber

+  HConstant* CopyToTruncatedNumber(Zone* zone);

[Jakob Kummerow, 2013/07/22 07:43:47]

This sounds more generic than it is. How about "CopyOddballToNumber"?

[Toon Verwaest, 2013/07/22 08:30:21]

I think the original name is fine. CopyToTruncatedInt32 doesn't handle all cases
either, and will return NULL if not possible. We could rename both to
TryCopyToTruncated* though.

On 2013/07/22 07:43:47, Jakob wrote:

[oliv, 2013/07/22 13:56:43]

How about returning Maybe<>, now it is clear, that the conversion is partial

   bool HasInteger32Value() const { return has_int32_value_; }
   int32_t Integer32Value() const {
     ASSERT(HasInteger32Value());
     return int32_value_;
   }
   bool HasSmiValue() const { return has_smi_value_; }
   bool HasDoubleValue() const { return has_double_value_; }
   double DoubleValue() const {
     ASSERT(HasDoubleValue());
     return double_value_;
@@ skipping 3317 matching lines @@
   virtual bool IsDeletable() const { return true; }
 };
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_