At the Need for Speed sprint, Tim Peters asked if
anyone had any need for integer bit operation
performance improvement.  Apparently, it's easy to
improve, but nobody has said they need this.  Please
reply to this task if you have an application which
needs this.

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Changed Category to Performance.  The idea with this one is
that the eval loop could easily inline "int & int", "int |
int", "int ^ int", much as it inlines "int + int" today.

To see what Tim's talking about here, see the 'big switch' ("switch 
opcode") in function PyEval_EvalFrameEx in Python/ceval.c, and look at the 
"case BINARY_ADD" bit.  Inlining the bitwise operators should be even 
easier, since there are no overflow worries.  (We do have to assume that C 
longs are two's-complement with no trap representation, but 
Objects/intobject.c does that already, so it's probably okay.)

This only applies to 'short' integers, so I don't think it's relevant for 
Python 3.x.

There's a related patch in issue 1087418.

I agree issue 1087418 is related, but why is it marked as a dependency for 
this issue?  It seems to me that either of these feature requests could be 
implemented independently of the other:  this one applies only to 2.x 
ints, while issue 1087418 applies only to 2.x longs and 3.x ints.

Mark: it was just my cluelessness showing :)

I don't think it's a good thing to special-case bitwise operations in
the ceval loop. It will make the whole thing less instruction
cache-friendly, just for the purpose of speeding up some very uncommon
operations.

It looks like no-one sees this as a useful optimization;  it seems even
less useful now given that it's not applicable to Python 3.x.

Closing.