[RISCV] Fix incomplete asm statement parsing

[luismarques]

Summary

For instructions without operands, the final AsmToken::EndOfStatement wasn't being consumed. In the context of inline assembly, the resulting empty statements would cause extraneous empty lines to be emitted. Fix the issue by consuming the EndOfStatement token.

[asb]

Nice catch, thanks.

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

if (Assembler != nullptr) {
       MAB.setForceRelocs();
     }
   }
 
   // First operand is token for instruction
   Operands.push_back(RISCVOperand::createToken(Name, NameLoc, isRV64()));
 
   // If there are no more operands, then finish
-  if (getLexer().is(AsmToken::EndOfStatement))
+  if (getLexer().is(AsmToken::EndOfStatement)) {
+    getParser().Lex(); // Consume the EndOfStatement.
     return false;
+  }
 
   // Parse first operand
   if (parseOperand(Operands, Name))
     return true;
 
   // Parse until end of statement, consuming commas between operands
   unsigned OperandIdx = 1;
   while (getLexer().is(AsmToken::Comma)) {

llvm/test/CodeGen/RISCV/large-stack.ll

 ; RV32I-FPELIM-NEXT:    sub sp, sp, a1
 ; RV32I-FPELIM-NEXT:    .cfi_def_cfa_offset 400016
 ; RV32I-FPELIM-NEXT:    lui a1, 78
 ; RV32I-FPELIM-NEXT:    addi a1, a1, 512
 ; RV32I-FPELIM-NEXT:    addi a2, sp, 8
 ; RV32I-FPELIM-NEXT:    add a1, a2, a1
 ; RV32I-FPELIM-NEXT:    #APP
 ; RV32I-FPELIM-NEXT:    nop
-; RV32I-FPELIM-EMPTY:
 ; RV32I-FPELIM-NEXT:    #NO_APP
 ; RV32I-FPELIM-NEXT:    sw a0, 0(a1)
 ; RV32I-FPELIM-NEXT:    #APP
 ; RV32I-FPELIM-NEXT:    nop
-; RV32I-FPELIM-EMPTY:
 ; RV32I-FPELIM-NEXT:    #NO_APP
 ; RV32I-FPELIM-NEXT:    lui a0, 97
 ; RV32I-FPELIM-NEXT:    addi a0, a0, 672
 ; RV32I-FPELIM-NEXT:    add sp, sp, a0
 ; RV32I-FPELIM-NEXT:    lw s0, 2028(sp) # 4-byte Folded Reload
 ; RV32I-FPELIM-NEXT:    lw s1, 2024(sp) # 4-byte Folded Reload
 ; RV32I-FPELIM-NEXT:    addi sp, sp, 2032
 ; RV32I-FPELIM-NEXT:    ret

 ; RV32I-WITHFP-NEXT:    lui a1, 78
 ; RV32I-WITHFP-NEXT:    addi a1, a1, 512
 ; RV32I-WITHFP-NEXT:    lui a2, 1048478
 ; RV32I-WITHFP-NEXT:    addi a2, a2, 1388
 ; RV32I-WITHFP-NEXT:    add a2, s0, a2
 ; RV32I-WITHFP-NEXT:    add a1, a2, a1
 ; RV32I-WITHFP-NEXT:    #APP
 ; RV32I-WITHFP-NEXT:    nop
-; RV32I-WITHFP-EMPTY:
 ; RV32I-WITHFP-NEXT:    #NO_APP
 ; RV32I-WITHFP-NEXT:    sw a0, 0(a1)
 ; RV32I-WITHFP-NEXT:    #APP
 ; RV32I-WITHFP-NEXT:    nop
-; RV32I-WITHFP-EMPTY:
 ; RV32I-WITHFP-NEXT:    #NO_APP
 ; RV32I-WITHFP-NEXT:    lui a0, 97
 ; RV32I-WITHFP-NEXT:    addi a0, a0, 688
 ; RV32I-WITHFP-NEXT:    add sp, sp, a0
 ; RV32I-WITHFP-NEXT:    lw ra, 2028(sp) # 4-byte Folded Reload
 ; RV32I-WITHFP-NEXT:    lw s0, 2024(sp) # 4-byte Folded Reload
 ; RV32I-WITHFP-NEXT:    lw s1, 2020(sp) # 4-byte Folded Reload
 ; RV32I-WITHFP-NEXT:    lw s2, 2016(sp) # 4-byte Folded Reload