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chipsalliance / rocket-chip

Rocket Chip Generator
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SLOI, SROI also need *_RV32 version; how REV, REV8, ORC_B instructions are related to b-ext. #2549

Open davidmlw opened 4 years ago

davidmlw commented 4 years ago

  1. Like RORI has RORI_RV32 version, I think SLOI and SROI also need *_RV32 version. https://github.com/chipsalliance/rocket-chip/blob/f1521796c292ee87958df6ea52f12145d869c83f/src/main/scala/rocket/Instructions.scala#L823

  2. REV, REV8, ORC_B are instructions from Zbb, while bitmanip defines them as pseudo instructions. Is it hte case? where is the REV, REV8 and ORC_B spec definitions?

aswaterman commented 4 years ago

Right. I'll update this stuff once the bitmanip task group makes decisions on what will be included.

Even though REV[8] and ORC.B are pseudoinstructions, it still helps to have them in this list, because some cores will implement only these forms, rather than implementing all of GORCI and GREVI.