[llvm] [AArch64][llvm] Gate some `tlbip` insns with either +tlbid or +d128 (PR #178913)

[Jonathan Thackray via llvm-commits]

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@@ -4264,12 +4264,24 @@ bool AArch64AsmParser::parseSyspAlias(StringRef Name, SMLoc NameLoc,
     const AArch64TLBIP::TLBIP *TLBIP = AArch64TLBIP::lookupTLBIPByName(Op);
     if (!TLBIP)
       return TokError("invalid operand for TLBIP instruction");
-    if (!getSTI().hasFeature(AArch64::FeatureD128) &&
-        !getSTI().hasFeature(AArch64::FeatureAll))
-      return TokError("instruction requires: d128");
+
     if (!TLBIP->haveFeatures(getSTI().getFeatureBits())) {
+      FeatureBitset Active = getSTI().getFeatureBits();
+      FeatureBitset Missing = TLBIP->getRequiredFeatures() & ~Active;
+
+      bool NeedD128OrTLBID =
+          TLBIP->allowTLBID() &&
+          !(Active[AArch64::FeatureD128] || Active[AArch64::FeatureTLBID]);
+
       std::string Str("instruction requires: ");
-      setRequiredFeatureString(TLBIP->getRequiredFeatures(), Str);
+      if (Missing.any())
+        setRequiredFeatureString(Missing, Str);
+
+      if (NeedD128OrTLBID) {
+        if (Missing.any())
+          Str += ", ";
+        Str += "tlbid or d128";
+      }
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jthackray wrote:

Now that #187400 has been merged, this removed the (erroneous) `+tlb-rmi` from `llvm/test/MC/AArch64/armv9a-tlbip.s`, which means I can mark this comment has resolved.

I've rebased this change on main (with minor edits) so it's now ready for approval, as this was the last remaining issue to be addressed.

https://github.com/llvm/llvm-project/pull/178913