Index: llvm/lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp
===================================================================
--- llvm/lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp
+++ llvm/lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp
@@ -1622,6 +1622,8 @@
     return MatchOperand_NoMatch;
   if (Lmul != 1 && Lmul != 2 && Lmul != 4 && Lmul != 8)
     return MatchOperand_NoMatch;
+  if (Fractional && Lmul == 1)
+    return MatchOperand_NoMatch;
   getLexer().Lex();
 
   if (!getLexer().is(AsmToken::Comma))
@@ -1631,9 +1633,9 @@
   Name = getLexer().getTok().getIdentifier();
   // ta or tu
   bool TailAgnostic;
-  if (Name.consume_front("ta"))
+  if (Name == "ta")
     TailAgnostic = true;
-  else if (Name.consume_front("tu"))
+  else if (Name == "tu")
     TailAgnostic = false;
   else
     return MatchOperand_NoMatch;
@@ -1646,9 +1648,9 @@
   Name = getLexer().getTok().getIdentifier();
   // ma or mu
   bool MaskedoffAgnostic;
-  if (Name.consume_front("ma"))
+  if (Name == "ma")
     MaskedoffAgnostic = true;
-  else if (Name.consume_front("mu"))
+  else if (Name == "mu")
     MaskedoffAgnostic = false;
   else
     return MatchOperand_NoMatch;
Index: llvm/test/MC/RISCV/rvv/invalid.s
===================================================================
--- llvm/test/MC/RISCV/rvv/invalid.s
+++ llvm/test/MC/RISCV/rvv/invalid.s
@@ -37,6 +37,15 @@
 vsetvli a2, a0, e8,m1z,tu,mu
 # CHECK-ERROR: operand must be e[8|16|32|64|128|256|512|1024],m[1|2|4|8|f2|f4|f8],[ta|tu],[ma|mu]
 
+vsetvli a2, a0, e8,mf1,tu,mu
+# CHECK-ERROR: operand must be e[8|16|32|64|128|256|512|1024],m[1|2|4|8|f2|f4|f8],[ta|tu],[ma|mu]
+
+vsetvli a2, a0, e8,m1,tu,mut
+# CHECK-ERROR: operand must be e[8|16|32|64|128|256|512|1024],m[1|2|4|8|f2|f4|f8],[ta|tu],[ma|mu]
+
+vsetvli a2, a0, e8,m1,tut,mu
+# CHECK-ERROR: operand must be e[8|16|32|64|128|256|512|1024],m[1|2|4|8|f2|f4|f8],[ta|tu],[ma|mu]
+
 vadd.vv v1, v3, v2, v4.t
 # CHECK-ERROR: operand must be v0.t