Why differ(!=,<>) is faster than equal(=,==)?

Question

I've seen comments on SO saying "<> is faster than =" or "!= faster than ==" in an if() statement.

I'd like to know why is that so. Could you show an example in asm?

Thanks! :)

EDIT:

Source

Here is what he did.

  function Check(var MemoryData:Array of byte;MemorySignature:Array of byte;Position:integer):boolean;
   var i:byte;
   begin
    Result := True; //moved at top. Your function always returned 'True'. This is what you wanted?
    for i := 0 to Length(MemorySignature) - 1 do //are you sure??? Perhaps you want High(MemorySignature) here... 
    begin
{!}  if MemorySignature[i] <> $FF then //speedup - '<>' evaluates faster than '='
     begin
      Result:=memorydata[i + position] <> MemorySignature[i]; //speedup.
      if not Result then 
        Break; //added this! - speedup. We already know the result. So, no need to scan till end.
     end;
    end;
   end;

Answer 1

I'd claim that this is flat out wrong except perhaps in very special circumstances. Compilers can refactor one into the other effortlessly (by just switching the if and else cases).

Answer 2

It could have something to do with branch prediction on the CPU. Static branch prediction would predict that a branch simply wouldn't be taken and fetch the next instruction. However, hardly anybody uses that anymore. Other than that, I'd say it's bull because the comparisons should be identical.