[RISCV] Change parseVTypeI function

[StephenFan]

Summary

Change parseVTypeI function to Make the added vset instruction test cases report more concrete error message.

[StephenFan]

ping.

[craig.topper]

llvm/lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp

1533

Can this be isNot?

1598

!VTypeIElements.empty()

[StephenFan]

Address craig.topper 's comment

[StephenFan]

Address @craig.topper 's comments

[craig.topper]

LGTM

llvm/lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp

if (getLexer().is(AsmToken::Identifier) &&
       getLexer().peekTok().is(AsmToken::Comma))
     return MatchOperand_NoMatch;
 
   return parseImmediate(Operands);
 }
 
 OperandMatchResultTy RISCVAsmParser::parseVTypeI(OperandVector &Operands) {
   SMLoc S = getLoc();
-  if (getLexer().getKind() != AsmToken::Identifier)
+  if (getLexer().isNot(AsmToken::Identifier))
     return MatchOperand_NoMatch;
 
-  // Parse "e8,m1,t[a|u],m[a|u]"
-  StringRef Name = getLexer().getTok().getIdentifier();
+  SmallVector<AsmToken, 7> VTypeIElements;
+  // Put all the tokens for vtypei operand into VTypeIElements vector.
+  while (getLexer().isNot(AsmToken::EndOfStatement)) {
+    VTypeIElements.push_back(getLexer().getTok());
+    getLexer().Lex();
+    if (getLexer().is(AsmToken::EndOfStatement))
+      break;
+    if (getLexer().isNot(AsmToken::Comma))
+      goto MatchFail;
+    AsmToken Comma = getLexer().getTok();
+    VTypeIElements.push_back(Comma);
+    getLexer().Lex();
+  }
+
+  if (VTypeIElements.size() == 7) {
+    // The VTypeIElements layout is:
+    // SEW comma LMUL comma TA comma MA
+    //  0    1    2     3    4   5    6
+    StringRef Name = VTypeIElements[0].getIdentifier();
     if (!Name.consume_front("e"))
-    return MatchOperand_NoMatch;
+      goto MatchFail;
     unsigned Sew;
     if (Name.getAsInteger(10, Sew))
-    return MatchOperand_NoMatch;
+      goto MatchFail;
     if (!RISCVVType::isValidSEW(Sew))
-    return MatchOperand_NoMatch;
-  getLexer().Lex();
+      goto MatchFail;
 
-  if (!getLexer().is(AsmToken::Comma))
-    return MatchOperand_NoMatch;
-  getLexer().Lex();
-
-  Name = getLexer().getTok().getIdentifier();
+    Name = VTypeIElements[2].getIdentifier();
     if (!Name.consume_front("m"))
-    return MatchOperand_NoMatch;
+      goto MatchFail;
     // "m" or "mf"
     bool Fractional = Name.consume_front("f");
     unsigned Lmul;
     if (Name.getAsInteger(10, Lmul))
-    return MatchOperand_NoMatch;
+      goto MatchFail;
     if (!RISCVVType::isValidLMUL(Lmul, Fractional))
-    return MatchOperand_NoMatch;
-  getLexer().Lex();
+      goto MatchFail;
 
-  if (!getLexer().is(AsmToken::Comma))
-    return MatchOperand_NoMatch;
-  getLexer().Lex();
-
-  Name = getLexer().getTok().getIdentifier();
     // ta or tu
+    Name = VTypeIElements[4].getIdentifier();
     bool TailAgnostic;
     if (Name == "ta")
       TailAgnostic = true;
     else if (Name == "tu")
       TailAgnostic = false;
     else
-    return MatchOperand_NoMatch;
-  getLexer().Lex();
-
-  if (!getLexer().is(AsmToken::Comma))
-    return MatchOperand_NoMatch;
-  getLexer().Lex();
+      goto MatchFail;
 
-  Name = getLexer().getTok().getIdentifier();
     // ma or mu
+    Name = VTypeIElements[6].getIdentifier();
     bool MaskAgnostic;
     if (Name == "ma")
       MaskAgnostic = true;
     else if (Name == "mu")
       MaskAgnostic = false;
     else
-    return MatchOperand_NoMatch;
-  getLexer().Lex();
-
-  if (getLexer().getKind() != AsmToken::EndOfStatement)
-    return MatchOperand_NoMatch;
+      goto MatchFail;
 
     unsigned SewLog2 = Log2_32(Sew / 8);
     unsigned LmulLog2 = Log2_32(Lmul);
     RISCVVSEW VSEW = static_cast<RISCVVSEW>(SewLog2);
     RISCVVLMUL VLMUL =
         static_cast<RISCVVLMUL>(Fractional ? 8 - LmulLog2 : LmulLog2);
 
     unsigned VTypeI =
         RISCVVType::encodeVTYPE(VLMUL, VSEW, TailAgnostic, MaskAgnostic);
     Operands.push_back(RISCVOperand::createVType(VTypeI, S, isRV64()));
-
     return MatchOperand_Success;
   }
 
+// If NoMatch, unlex all the tokens that comprise a vtypei operand
+MatchFail:
+  while (!VTypeIElements.empty())
+    getLexer().UnLex(VTypeIElements.pop_back_val());
+  return MatchOperand_NoMatch;
+}
+
 OperandMatchResultTy RISCVAsmParser::parseMaskReg(OperandVector &Operands) {
   switch (getLexer().getKind()) {
   default:
     return MatchOperand_NoMatch;
   case AsmToken::Identifier:
     StringRef Name = getLexer().getTok().getIdentifier();
     if (!Name.consume_back(".t")) {
       Error(getLoc(), "expected '.t' suffix");

llvm/test/MC/RISCV/rvv/invalid.s

 # RUN: not llvm-mc -triple=riscv64 --mattr=+experimental-v --mattr=+f %s 2>&1 \
 # RUN:        | FileCheck %s --check-prefix=CHECK-ERROR
 
 vsetivli a2, 32, e8,m1
-# CHECK-ERROR: unknown operand
+# CHECK-ERROR: immediate must be an integer in the range [0, 31]
 
 vsetivli a2, zero, e8,m1
-# CHECK-ERROR: unknown operand
+# CHECK-ERROR: immediate must be an integer in the range [0, 31]
 
 vsetivli a2, 5, e31
 # 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, e31
 # 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, e32,m3

 # 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]
 
+vsetvli a2, a0, e8
+# 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
+# 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,ta
+# 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
 
 vadd.vv v1, v3, v2, v0
 # CHECK-ERROR: expected '.t' suffix
 
 vadd.vv v1, v3, a0
 # CHECK-ERROR: invalid operand for instruction