[llvm] [RISC-V] Add P-ext MC Support for More Pair Operations (PR #154088)

[Craig Topper via llvm-commits]

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@@ -149,6 +149,48 @@ class RVPShiftB_ri<bits<3> f, bits<3> funct3, string opcodestr>
   let Inst{22-20} = shamt;
 }
 
+class RVPPairShift_ri<bits<3> f, string opcodestr, Operand ImmType>
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topperc wrote:

The `ri` vs `pi` might be too subtle to spot.

Maybe

Input\Output | GPR | GPRPair
-- | -- | --
GPR | RVPShift_ri (existing) | RVPWideningShift_ri
GPRPair | RVPNarrowingShift_ri | RVPPairShift_ri


https://github.com/llvm/llvm-project/pull/154088