mips type R, I and J, RS, RT and RD fields length

Question

Is there any particular reason why RS, RT and RD fields have 5 bits?

Pavan Manjunath · Accepted Answer · 2022-07-12T18:56:47.300

4

MIPS has 32 integer registers and 32 floating point registers and hence 5 bits are needed to represent each set of 32 registers.

The register letters d, t, and s are placeholders for (register) numbers or register names.

Read more on Wikipedia and also here

edited Jul 12 '22 at 18:56

answered Apr 24 '12 at 18:41

Pavan Manjunath

That is indeed the reason. The smallest storage space that is capable of holding every register value. The RS = source register, RD = destination register. (RT actually has a few purposes) – Wiz Apr 25 '12 at 02:30
That should have said every register number not value. Typo. – Wiz Apr 25 '12 at 06:29
Hi, the "University of Minnesota" url is inactive since years. This is the most recent archived page: http://web.archive.org/web/20121010181500/https://www.d.umn.edu/~gshute/spimsal/talref.html – ABO Jul 06 '22 at 14:25
@ABO Thanks. I've updated my answer to reflect the link you provided. – Pavan Manjunath Jul 12 '22 at 18:57

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