[llvm] [RISCV][MC] Recognise that fcvt.d.s with frm != 0b000 is valid (PR #67555)

[Alex Bradbury via llvm-commits]

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@@ -158,6 +158,16 @@ void RISCVInstPrinter::printFRMArg(const MCInst *MI, unsigned OpNo,
   O << ", " << RISCVFPRndMode::roundingModeToString(FRMArg);
 }
 
+void RISCVInstPrinter::printFRMArgLegacy(const MCInst *MI, unsigned OpNo,
+                                         const MCSubtargetInfo &STI,
+                                         raw_ostream &O) {
+  auto FRMArg =
+      static_cast<RISCVFPRndMode::RoundingMode>(MI->getOperand(OpNo).getImm());
+  if (PrintAliases && !NoAliases && FRMArg == RISCVFPRndMode::RoundingMode::RNE)
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asb wrote:

Good idea, I've made that change. I don't imagine no aliases is commonly used outside of our own backend tests, but no harm in being cautious here.

https://github.com/llvm/llvm-project/pull/67555