Fast math

Here I will collect my fast math ASM functions for 6502/6510.
Next will be sin/cos using CORDIC algorithm for fixed point 32-bit data which requires only SHIFT and MUL operations.

At first simple mul in various forms.

It is pure code without any license so I can say open source.
I've made it only for a hobby and to try to get the fastest way to do a math function, checking them to get the lowest, as possible, cpu tick needs.
Use it freely.

PS: The code was developed and debugged with the CBMprgStudio V1.0 default assembler so make your required changes to work with your assembler.

Quote from 8R0TK4$T3N

Those snippets might be useful for this repository: https://github.com/TobyLobster/multiply_test/tree/main

Very interesting link.
Thank you.

I've a lot of very fast math made for Hitachi 63701 to move low to 6502 (it has a D 16-bit register and some instructions that 6502 does not have and to remove).
I used them in late 1988-90 to manage industrial instrumentation for axis positioning... I will do.

Quote from peiselulli

This is faster

I know.
Very fast, but requires 2k tables that I would like to avoid.
Zero page is also almost used by C64, leaving free only $F9, $FB, and $FC addresses for generic use.
Nice technique, however.