From 044395306702fc47e63b43d5ad961a127c19b262 Mon Sep 17 00:00:00 2001 From: Ethan Furman Date: Fri, 2 Sep 2016 15:50:21 -0700 Subject: issue23591: optimize _high_bit() --- Lib/enum.py | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/Lib/enum.py b/Lib/enum.py index 8369631..8d23933 100644 --- a/Lib/enum.py +++ b/Lib/enum.py @@ -784,13 +784,8 @@ class IntFlag(int, Flag): def _high_bit(value): - """return the highest bit set in value""" - bit = 0 - while 'looking for the highest bit': - limit = 2 ** bit - if limit > value: - return bit - 1 - bit += 1 + """returns index of highest bit, or -1 if value is zero or negative""" + return value.bit_length() - 1 if value > 0 else -1 def unique(enumeration): """Class decorator for enumerations ensuring unique member values.""" -- cgit v0.12