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

[David Spickett via cfe-commits]

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@@ -13,3 +13,57 @@
 // RUN: %clang --target=aarch64_be -mbig-endian -march=armv8.6a -### -c %s 2>&1 | FileCheck -check-prefix=GENERICV86A-BE %s
 // RUN: %clang --target=aarch64_be -mbig-endian -march=armv8.6-a -### -c %s 2>&1 | FileCheck -check-prefix=GENERICV86A-BE %s
 // GENERICV86A-BE: "-cc1"{{.*}} "-triple" "aarch64_be{{.*}}" "-target-cpu" "generic" "-target-feature" "+v8.6a"{{.*}} "-target-feature" "+neon"
+
+// ===== Architecture extensions =====
+
+// RUN: %clang -target aarch64 -march=armv8.6-a --print-enabled-extensions 2>&1 | FileCheck -check-prefix=ARCH-EXTENSION --implicit-check-not FEAT_ %s
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DavidSpickett wrote:

What is the implicit-check-not doing here? Or rather, what possible bug is it making sure we don't miss?

Is it that in the information we list the names as "AMUv1" for example, so if we forgot to add a name, we'd output just "FEAT_" ?

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