[llvm] [RISCV][llvm] Preliminary P extension codegen support (PR #162668)

[Brandon Wu via llvm-commits]

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@@ -809,6 +809,7 @@ struct RISCVOperand final : public MCParsedAsmOperand {
 
   bool isSImm5() const { return isSImm<5>(); }
   bool isSImm6() const { return isSImm<6>(); }
+  bool isSImm8() const { return isSImm<8>(); }
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4vtomat wrote:

Oh, we cant use pattern match, we need to select manually since we have to convert to canonical form when doing instruction selection right

https://github.com/llvm/llvm-project/pull/162668