[llvm] [AArch64] Emit .arch and .arch_extension during assembly to textual asm (PR #138433)

[Zachary Yedidia via llvm-commits]

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@@ -7234,6 +7236,8 @@ bool AArch64AsmParser::parseDirectiveArchExtension(SMLoc L) {
     STI.ClearFeatureBitsTransitively(It->Features);
   FeatureBitset Features = ComputeAvailableFeatures(STI.getFeatureBits());
   setAvailableFeatures(Features);
+
+  getTargetStreamer().emitDirectiveArchExtension(Name);
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zyedidia wrote:

Thank you for catching that. I have updated the code so that it emits the full name from before the `no` prefix is stripped, along with a test. Let me know if you'd like further changes.

https://github.com/llvm/llvm-project/pull/138433