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crackez10/11/20241 replyview on HN

Yet the same number of register bytes (when only counting 6502's zero page)... 32x8 = 256 bytes...


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brucehoult10/12/2024

31x4 = 124 bytes :-) The Zero register doesn't have to physically exist, and we're talking about 32 bit CPUs e.g. Pi Pico 2 here, right.

Ok, 128 bytes if you add in the PC.

Except for RV32E -- as seen in the very popular $0.10 CH32V003 -- which has 15x4 = 60 bytes of GPRs, plus the PC.

Plus usually a few CSRs on practical CPUs, though Zicsr is an extension so you don't have to have it.