[Python-Dev] Accessing globals without dict lookup

Tim Peters tim.one@comcast.net
Tue, 12 Feb 2002 15:17:50 -0500

> Speaking of which, why does LOAD_FAST waste time checking against NULL
> twice?!

[Neil Schemenauer]
> If you would have approved my patch it would be fixed already.

Heh.  If you had entered the patch at priority 9, I might have gotten to it
by this summer.  At priority 3, we're talking years <wink/sigh>.  I boosted
it to 6.  Note that the tiny patch I checked in also rearranged the code so
that the mormal case became the fall-through case:

    if (normal)
        do normal stuff
    else do exceptional stuff

Most dumb compilers on platforms that care use a "forward branches probably
aren't taken, backward branches probably are" heuristic for setting
branch-prediction hints in the machine code; and on platforms that don't
care it's usually faster to fall through than to change the program counter

>   one-small-banana-left-ly y'rs Neil

is-that-an-american-or-canadian-banana?-ly y'rs  - tim