[clang] [llvm] [AArch64] Add ability to list extensions enabled for a target (PR #95805)

[Tomas Matheson via cfe-commits]

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@@ -1841,7 +1868,8 @@ INSTANTIATE_TEST_SUITE_P(
                  AArch64::AEK_PROFILE, AArch64::AEK_RAND,
                  AArch64::AEK_FP16FML, AArch64::AEK_I8MM,
                  AArch64::AEK_JSCVT,   AArch64::AEK_FCMA,
-                 AArch64::AEK_PAUTH,   AArch64::AEK_PERFMON}),
+                 AArch64::AEK_PAUTH,   AArch64::AEK_PERFMON,
+                 AArch64::AEK_CCDP}),
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tmatheson-arm wrote:

We should think about whether we want each AEK to correspond to a `-march` modifier (status quo) or whether we want it to correspond to an `Extension` like here.

https://github.com/llvm/llvm-project/pull/95805