Brooke Vibber
c7e7129eb2
whoops missed a few cycs
2023-01-05 11:55:41 -08:00
Brooke Vibber
2340f8210e
update round & sketch out the iter cycle count
2023-01-05 11:36:42 -08:00
Brooke Vibber
7f70f14fc2
one last round sketch
...
combining copy and round
2023-01-05 11:17:13 -08:00
Brooke Vibber
7ac0df0343
Added two version of 16-bit rounding
...
round16_incdec uses inc and dec
round16_addsub uses adc and sbc
the incdec version is the same when no rounding is needed
but saves about 8 cycles on the rounding cases, for an
average savings of 4.5 cycles for randomly distributed inputs
untested so far
2023-01-05 09:06:07 -08:00
Brooke Vibber
6edd2f71d9
whoops added wrong
2023-01-04 21:26:47 -08:00
Brooke Vibber
373e1441d3
comment tweaks
2023-01-04 21:09:45 -08:00
Brooke Vibber
3a0545b673
tyop
2023-01-04 21:04:53 -08:00
Brooke Vibber
1408855eed
Note how many cycles loop unrolling saves
...
+4 cycles one-time setup
ldx #8 ; 2 cyc for first 8
ldx #8 ; 2 cyc for second 8 (different shift behavior)
-5 cycles/iter to get bit now
lsr arg + 1 ; 5 cyc
rol arg ; 5 cyc
+10 cycles/iter to get the bit in a loop
dex ; 2 cyc
bne ; 2 cyc
4 cycles/iter for the loop
4 + (14 * 16) = 4 + 224 = 228
2023-01-04 21:02:18 -08:00
Brooke Vibber
519f8ad635
whoops
2023-01-04 20:57:07 -08:00
Brooke Vibber
efd722eeb2
update cycle count for imul16
2023-01-04 20:37:16 -08:00
Brooke Vibber
41915cf122
save a few bytes by removing a dupe tail from two cases now
2023-01-04 20:33:42 -08:00
Brooke Vibber
38091e535f
hmm
2023-01-04 20:31:39 -08:00
Brooke Vibber
58519381bf
hmm
2023-01-04 20:12:34 -08:00
Brooke Vibber
fa599be775
wip fix
2023-01-04 19:52:56 -08:00
Brooke Vibber
9682b4a6b3
readme
2023-01-04 19:15:26 -08:00
Brooke Vibber
5605cc4652
woo
2022-12-30 18:25:43 -08:00
Brooke Vibber
2d67cdc498
woo
2022-12-30 18:21:31 -08:00
Brooke Vibber
4b1001bfdc
annotate cycle counts
2022-12-30 17:33:18 -08:00
Brooke Vibber
6583dc3680
wip
2022-12-30 01:05:52 -08:00
Brooke Vibber
f50882a24d
maybe
2022-12-30 00:55:48 -08:00
Brooke Vibber
27d046011e
looks workable
2022-12-30 00:43:44 -08:00
Brooke Vibber
fe9a35353b
works for 3 * 5 = 15
2022-12-29 20:32:58 -08:00
Brooke Vibber
b307f98760
nice
2022-12-29 20:18:21 -08:00
Brooke Vibber
ca877ef44d
hmm
2022-12-29 03:37:51 -08:00
Brooke Vibber
e6c05d0f66
stuff
2022-12-28 21:08:16 -08:00
Brooke Vibber