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Comment by cassepipe

5 hours ago

Curious: What does the "imac" stand for in the architecture target name ?

IMAC are the RISC-V extensions supported:

I = Base integer instruction set, 32-bit

M = Standard extension for integer multiplication and division

A = Standard extension for atomic instructions

C = Standard extension for compressed instructions

https://en.wikipedia.org/wiki/RISC-V#ISA_base_and_extensions

  • Thanks.I can't believe they chose non-arcane, memory-friendly letters. Kind of rare in naming hardware I feel (unless it's not ?)

    • The core set of extensions has pretty friendly single letters, but the flip side is you run out of letters pretty quickly.

      The non-single-letter extensions should make you feel more at home. Like the supervisor instructions. You have Smcntrpmf which helps with benchmarking by pausing perf counters during traps. I think Smcntrpmf just rolls off the tongue nicely.

      Then there's a lot of extensions that start with Z followed by a sprinkling of random letters which is secretly an abbreviation you couldn't have guessed. For instance you have your SHA-2 instructions in Zvknha and Zvknhb, since that's the Vector Krypto NIST Hashes.

    • I see you are unfamiliar with `rv64mafdcbvh_zicsr_zicntr_zihpm_ziccif_ziccrse_ziccrse_ziccamoa_zicclsm_za64rs_zihintpause_zic64b_zicbom_zicbop_zicboz_zfhmin_zkt_zihintntl_zicond_zimop_zcmop_zcb_zfa_zawrs_supm_svade_ssccptr_sstvecd_sstvala_sscounterenw_svpbmt_svinval_svnapot_sstc_sscofpmf_ssnpm_ssu64xl_sstateen_shcounterenw_shvstvala_shtvala_shvstvecd_shvsatpa_shgatpa` also known as `RVA23`