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riscv / riscv-bitmanip

Working draft of the proposed RISC-V Bitmanipulation extension
https://jira.riscv.org/browse/RVG-122
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Should the instruction listings be purely in alphabetical order, or in logical order? #137

Open BrianGraysonSiV opened 3 years ago

BrianGraysonSiV commented 3 years ago

For many extensions, there's a pattern where both the alphabetical order and the logical order agree:

foo foow bar barw baz bazw

This pattern is broken when we get to the rotate instructions, where we end up listing ror, rori, roriw, rorw, which breaks the logical parallelism but maintains the (less-important?) alphabetical ordering.

When I was reading it the first time, I expected the instructions were in the logical order, not in alphabetical order, and got confused by the ror/rori/roriw/rorw ordering. I don't know which of these two we want to do.

This also crops up in min/max. It's titled min/max, the text talks about min then max, but then the listing does max then min, due to alphabetical order.