Posted By
Litwr
on 2013-08-02
13:28:26
|  Re: Z80 GUI: SymbOS
I'm not optimizing compiler!  I've just made proof that z80 is 3 times slower with strings (up to 65534 chars) compare. The page boundary crossings will add about 1 cycles and this may reduce ratio to 1:2.85 but they maybe avoided by passing proper initial x and y values to the subroutine. Sorry I wrote more 6502 code than I should - 4 lines are excessive - we do not need to increase low byte of string address - this reduces code by 10 bytes. So z80 code will be only 2 times shorter now!
IMHO the code with addition for z80 will be at least 4 times slower. 
[***edit] Sorry, this 1 cycle cannot be removed. So finally we have 1:2.85 ratio.
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