[RISCV] Add OperandType for sew and vecpolicy operands.

Author: topperc

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

@@ -335,7 +335,11 @@ enum OperandType : unsigned {
   OPERAND_FRMARG,
   // Operand is a 3-bit rounding mode where only RTZ is valid.
   OPERAND_RTZARG,
-  OPERAND_LAST_RISCV_IMM = OPERAND_RTZARG,
+  // Vector policy operand.
+  OPERAND_VECPOLICY,
+  // Vector SEW operand.
+  OPERAND_SEW,
+  OPERAND_LAST_RISCV_IMM = OPERAND_SEW,
   // 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

@@ -2542,6 +2542,12 @@ bool RISCVInstrInfo::verifyInstruction(const MachineInstr &MI,
         case RISCVOp::OPERAND_RTZARG:
           Ok = Imm == RISCVFPRndMode::RTZ;
           break;
+        case RISCVOp::OPERAND_VECPOLICY:
+          Ok = (Imm & (RISCVII::TAIL_AGNOSTIC | RISCVII::MASK_AGNOSTIC)) == Imm;
+          break;
+        case RISCVOp::OPERAND_SEW:
+          Ok = Imm == 0 || (Imm >= 3 && Imm <= 6);
+          break;
         }
         if (!Ok) {
           ErrInfo = "Invalid immediate";