[AMDGPU][MC][GFX11][NFC] Correct VOPD parsing

[dp]

Summary

Instruction opcode for the Y operation is currently stored as an expression operand. This may cause incorrect detection of error position by getLitLoc. Currently, it does not because VOPD instructions are not validated by the parser.

This change is required for VOPD validation which is WIP.

[Joe_Nash]

LGTM

llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp

OperandMatchResultTy AMDGPUAsmParser::parseVOPD(OperandVector &Operands) {
   if (!hasVOPD(getSTI()))
     return MatchOperand_NoMatch;
 
   if (isToken(AsmToken::Colon) && peekToken(false).is(AsmToken::Colon)) {
     SMLoc S = getLoc();
     lex();
     lex();
     Operands.push_back(AMDGPUOperand::CreateToken(this, "::", S));
-    const MCExpr *Expr;
-    if (isToken(AsmToken::Identifier) && !Parser.parseExpression(Expr)) {
-      Operands.push_back(AMDGPUOperand::CreateExpr(this, Expr, S));
+    StringRef OpYName;
+    if (isToken(AsmToken::Identifier) && !Parser.parseIdentifier(OpYName)) {
+      Operands.push_back(AMDGPUOperand::CreateToken(this, OpYName, S));
       return MatchOperand_Success;
     }
     Error(S, "invalid VOPD :: usage");
     return MatchOperand_ParseFail;
   }
   return MatchOperand_NoMatch;
 }