Index: llvm/lib/Target/RISCV/MCTargetDesc/RISCVInstPrinter.cpp
===================================================================
--- llvm/lib/Target/RISCV/MCTargetDesc/RISCVInstPrinter.cpp
+++ llvm/lib/Target/RISCV/MCTargetDesc/RISCVInstPrinter.cpp
@@ -170,6 +170,12 @@
 void RISCVInstPrinter::printVTypeI(const MCInst *MI, unsigned OpNo,
                                    const MCSubtargetInfo &STI, raw_ostream &O) {
   unsigned Imm = MI->getOperand(OpNo).getImm();
+  // The encoding vlmul[2:0]=4 is reserved, so we just print the immediate.
+  if ((Imm & 7) == 4) {
+    O << Imm;
+    return;
+  }
+  // Print the text form.
   RISCVVType::printVType(Imm, O);
 }
 
Index: llvm/test/MC/RISCV/rvv/vsetvl-invalid.s
===================================================================
--- /dev/null
+++ llvm/test/MC/RISCV/rvv/vsetvl-invalid.s
@@ -0,0 +1,28 @@
+# RUN: llvm-mc -filetype=obj -triple=riscv32 %s \
+# RUN:     | llvm-objdump -d --mattr=+experimental-v - | FileCheck %s
+# RUN: llvm-mc -filetype=obj -triple=riscv64 %s \
+# RUN:     | llvm-objdump -d --mattr=+experimental-v - | FileCheck %s
+
+# CHECK: vsetvli a1, a0, e64, m1, tu, mu
+.word 0x018575d7
+
+# CHECK: vsetvli a1, a0, 28
+.word 0x01c575d7
+
+# CHECK: vsetvli a1, a0, 36
+.word 0x024575d7
+
+# CHECK: vsetvli a1, a0, e64, mf8, tu, mu
+.word 0x01d575d7
+
+# CHECK: vsetivli a1, 16, e8, m4, tu, mu
+.word 0xc02875d7
+
+# CHECK: vsetivli a1, 16, 12
+.word 0xc0c875d7
+
+# CHECK: vsetivli a1, 16, 52
+.word 0xc34875d7
+
+# CHECK: vsetivli a1, 16, e8, mf4, tu, mu
+.word 0xc06875d7