[clang] [llvm] [AArch64] Decouple feature dependency expansion. (PR #94279)

[Tomas Matheson via llvm-commits]

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@@ -250,13 +248,17 @@ void AArch64::ExtensionSet::addArchDefaults(const ArchInfo &Arch) {
 bool AArch64::ExtensionSet::parseModifier(StringRef Modifier) {
   LLVM_DEBUG(llvm::dbgs() << "parseModifier(" << Modifier << ")\n");
 
-  bool IsNegated = Modifier.starts_with("no");
-  StringRef ArchExt = IsNegated ? Modifier.drop_front(2) : Modifier;
+  size_t NChars = 0;
+  if (Modifier.starts_with("no-"))
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tmatheson-arm wrote:

Will this enable `no-` prefix in `-march` whereas it was only enabled in the target attribute before?

https://github.com/llvm/llvm-project/pull/94279