Index: llvm/lib/Target/RISCV/RISCVInstrInfo.cpp
===================================================================
--- llvm/lib/Target/RISCV/RISCVInstrInfo.cpp
+++ llvm/lib/Target/RISCV/RISCVInstrInfo.cpp
@@ -1220,6 +1220,15 @@
     }
   }
 
+  uint64_t TSFlags = MI.getDesc().TSFlags;
+  if (RISCVII::hasVLOp(TSFlags) && !RISCVII::hasSEWOp(TSFlags)) {
+    ErrInfo = "VL operand w/o SEW operand?";
+    return false;
+  }
+  if (RISCVII::hasVecPolicyOp(TSFlags) && !RISCVII::hasVLOp(TSFlags)) {
+    ErrInfo = "policy operand w/o SEW operand?";
+    return false;
+  }
   return true;
 }