Senior Member
Joined: 30/11/2020
Location: LithuaniaPosts: 299
| Posted: 03:05pm 06 Aug 2024 |
I know too SUB`s must inefficient, and that DEC idea was only to make it pretty, yes.
I wrote once some bit manipulation functions bit.set, bit.res, bit.test only becouse it was fun and nostalgic but not the most efficient way
So yes, there are many ways to solve same task .. CSUB`s etc.. :)
Wrote them while writing z80 disasm :D
function bit_res.0 (bt)
bit_res.0=bt and 254
end function
function bit_res.1 (bt)
bit_res.1=bt and 253
end function
function bit_res.2 (bt)
bit_res.2=bt and 251
end function
function bit_res.3 (bt)
bit_res.3=bt and 247
end function
function bit_res.4 (bt)
bit_res.4=bt and 239
end function
function bit_res.5 (bt)
bit_res.5=bt and 223
end function
function bit_res.6 (bt)
bit_res.6=bt and 191
end function
function bit_res.7 (bt)
bit_res.7=bt and 127
end function
bit_res.0=bt and 254
end function
function bit_res.1 (bt)
bit_res.1=bt and 253
end function
function bit_res.2 (bt)
bit_res.2=bt and 251
end function
function bit_res.3 (bt)
bit_res.3=bt and 247
end function
function bit_res.4 (bt)
bit_res.4=bt and 239
end function
function bit_res.5 (bt)
bit_res.5=bt and 223
end function
function bit_res.6 (bt)
bit_res.6=bt and 191
end function
function bit_res.7 (bt)
bit_res.7=bt and 127
end function
function bit_set.0 (bt)
bit_set.0=bt or 1
end function
function bit_set.1 (bt)
bit_set.1=bt or 2
end function
function bit_set.2 (bt)
bit_set.2=bt or 4
end function
function bit_set.3 (bt)
bit_set.3=bt or 8
end function
function bit_set.4 (bt)
bit_set.4=bt or 16
end function
function bit_set.5 (bt)
bit_set.5=bt or 32
end function
function bit_set.6 (bt)
bit_set.6=bt or 64
end function
function bit_set.7 (bt)
bit_set.7=bt or 128
end function
' test bit. If bit set, returns 1 if offset returns 0
function bit.0 (test_byte) as integer
bit.0=(test_byte and 1)
end function
function bit.1 (test_byte) as integer
bit.1=(test_byte and 2) >> 1
end function
function bit.2 (test_byte) as integer
bit.2=(test_byte and 4) >> 2
end function
function bit.3 (test_byte) as integer
bit.3=(test_byte and 8) >> 3
end function
function bit.4 (test_byte) as integer
bit.4=(test_byte and 16) >> 4
end function
function bit.5 (test_byte) as integer
bit.5=(test_byte and 32) >> 5
end function
function bit.6 (test_byte) as integer
bit.6=(test_byte and 64) >> 6
end function
function bit.7 (test_byte) as integer
bit.7=(test_byte and 128) >> 7
end function