[RISCV] Add OperandType for vector rounding mode operands.

llvm/lib/Target/RISCV/MCTargetDesc/RISCVBaseInfo.h

@@ -337,7 +337,13 @@ enum OperandType : unsigned {
   OPERAND_RTZARG,
   // Condition code used by select and short forward branch pseudos.
   OPERAND_COND_CODE,
-  OPERAND_LAST_RISCV_IMM = OPERAND_COND_CODE,
+  // Vector policy operand.
+  OPERAND_VEC_POLICY,
+  // Vector SEW operand.
+  OPERAND_SEW,
+  // Vector rounding mode for VXRM or FRM.
+  OPERAND_VEC_RM,
+  OPERAND_LAST_RISCV_IMM = OPERAND_VEC_RM,
   // Operand is either a register or uimm5, this is used by V extension pseudo
   // instructions to represent a value that be passed as AVL to either vsetvli
   // or vsetivli.

llvm/lib/Target/RISCV/RISCVInstrInfo.cpp

@@ -2545,6 +2545,19 @@ bool RISCVInstrInfo::verifyInstruction(const MachineInstr &MI,
         case RISCVOp::OPERAND_COND_CODE:
           Ok = Imm >= 0 && Imm < RISCVCC::COND_INVALID;
           break;
+        case RISCVOp::OPERAND_VEC_POLICY:
+          Ok = (Imm & (RISCVII::TAIL_AGNOSTIC | RISCVII::MASK_AGNOSTIC)) == Imm;
+          break;
+        case RISCVOp::OPERAND_SEW:
+          Ok = Imm == 0 || (Imm >= 3 && Imm <= 6);
+          break;
+        case RISCVOp::OPERAND_VEC_RM:
+          assert(RISCVII::hasRoundModeOp(Desc.TSFlags));
+          if (RISCVII::usesVXRM(Desc.TSFlags))
+            Ok = isUInt<2>(Imm);
+          else
+            Ok = RISCVFPRndMode::isValidRoundingMode(Imm);
+          break;
         }
         if (!Ok) {
           ErrInfo = "Invalid immediate";