RPL second impressions (HP 28)

[rprosperi]

(05-27-2022 06:07 PM)Thomas Klemm Wrote:  [snip...]

To me that looks similar to the SysRPL code.
Entry points start with %% and instead of using assembler to deal with registers, it uses stack shuffling instructions.
Maybe not a surprise as both use the same algorithm.

It's not surprising since many many members that worked on the 71B OS and IDS went on to work on the 28C/S and then the 48 ROM. Most folks don't realize that a vast majority of the underlying math libraries/routines in all post 71B machines up through the 50g are based on the foundation laid by the 71B OS. Cyrille has even commented that much of the 39GII and Prime's "guts" re-uses much of the same stuff, though ported to C for portability.