Performance

Tested using CRoaring's census1881 dataset on the travis build 552223545:

OP	TIME/OP (us)	ST.DEV. (us)
R.SETBIT	19.44	4.00
R64.SETBIT	19.35	5.75
SETBIT	18.90	4.99
R.GETBIT	18.74	1.28
R64.GETBIT	18.80	1.25
GETBIT	18.40	2.31
R.BITCOUNT	14.96	0.04
R64.BITCOUNT	14.76	0.03
BITCOUNT	38.18	0.17
R.BITPOS	19.69	0.05
R64.BITPOS	20.17	0.08
BITPOS	27.92	0.27
R.BITOP NOT	38.39	0.52
R64.BITOP NOT	36.97	0.54
BITOP NOT	62.43	0.32
R.BITOP AND	22.95	0.10
R64.BITOP AND	28.89	0.20
BITOP AND	163.28	2.75
R.BITOP OR	27.29	0.64
R64.BITOP OR	25.09	0.16
BITOP OR	210.42	3.75
R.BITOP XOR	23.68	0.15
R64.BITOP XOR	24.83	0.17
BITOP XOR	185.91	3.24
R.BITOP ANDOR	22.97	0.09
R64.BITOP ANDOR	23.45	0.11
BITOP ANDOR	211.66	3.74
R.BITOP ONE	23.86	0.15
R64.BITOP ONE	26.36	0.21
BITOP ONE	209.89	3.70
R.MIN	19.63	0.03
R64.MIN	20.33	0.07
MIN	20.36	0.06
R.MAX	19.85	0.04
R64.MAX	19.49	0.03
MAX	19.94	0.06