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22:00:32
phoe
What is an efficient way to check if a bit vector contains any non-zero bits?
22:00:48
phoe
trying to (= 0 (reduce #'+ bit-vector)) makes a full call to #'REDUCE
22:05:43
phoe
FIND looks like an okay choice, it gets compiled into a call to SB-KERNEL:%BIT-POS-FWD/1
22:06:34
_death
(some #'plusp x) looks better
22:07:13
_death
especially if it's a simple-bit-vector
22:20:54
stassats
how does (some #'plusp x) look better?
22:21:00
stassats
if by better you mean slower?
22:26:59
phoe
no, I mean, I seriously don't know at the moment - I can't figure out which assembly looks better in that case
22:27:35
stassats
i suggest testing, not looking at the assembly
22:30:10
_death
right.. it tests bit by bit
22:30:21
stassats
huh, how come POSITION which returns something conses on ARM64
22:38:10
stassats
(LOGAND #<SB-KERNEL:CONSTANT :VALUE 0 {7013262A83}> 18446744073709551615)
22:38:10
stassats
; note: forced to do LOGAND-WORD-MASK (cost 10)
22:38:20
stassats
how did SB-KERNEL:CONSTANT get there
22:43:42
stassats
but that shouldn't cons
22:45:03
stassats
but it conses when inside POSITION
22:47:43
stassats
ok, i'm testing on different values
22:55:11
stassats
phoe: it's your fault!
22:56:02
phoe
ACTION switches to ABCL as his daily driver
22:56:45
stassats
having a machine that you actually use makes a lot of difference
22:57:17
stassats
it's been what, six years since i did the arm64 port, but haven't really used it beyond testing
22:58:57
stassats
phoe: you don't know what slow is until you try ABCL
23:00:33
stassats
but how do i get back to SB-KERNEL:CONSTANT :VALUE 0
23:01:15
stassats
i guess by reverting the change
23:03:16
stassats
maybe i can just pretend i didn't see that
23:06:19
stassats
i guess modarith is slicing something bogus
0:16:53
OMGOMG
stassats: hey, did you know your nick can mean "fancy moonshine" in swedish?
0:22:34
stassats
"fancy" and "moonshine" sounds weird, though
0:23:22
stassats
how fancy would a moonshine be until it's no longer moonshine
0:25:51
OMGOMG
more accurately the grammar would probably be "moonshine for a fancy occasion" but i was trying to keep it short
0:26:12
OMGOMG
i guess it can also mean fancy ejaculation, if you prefer