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RISC-V Instruction Set Manual
https://riscv.org/
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Is Ziccrse compatible with rv32i? #1538

Open palmer-dabbelt opened 1 year ago

palmer-dabbelt commented 1 year ago

There's a bunch of new extensions listed in the profile document that are only defined by being mandatory in some profiles that require rv64i. Are these meant to also be legal extensions to other base ISAs?

aswaterman commented 1 year ago

Most or all of them could be compatible with RV32I (and the other base ISAs), and the intent wasn't to imply otherwise.

I agree with the point you're driving at, though: the strategy of implicitly defining these extensions within profiles leaves it unstated whether these extensions are only defined for the profile's base ISA, or whether they're more broadly scoped.

kasanovic commented 1 year ago

For now, the names are being introduced in the context of profiles. Many of them should be later expanded within the context of priv arch spec.