[clang] [llvm] [AIX] support builtin_cpu_is() for aix (PR #80069)

[Nemanja Ivanovic via cfe-commits]

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@@ -362,8 +362,18 @@ class LLVM_LIBRARY_VISIBILITY PPCTargetInfo : public TargetInfo {
 
   // We support __builtin_cpu_supports/__builtin_cpu_is on targets that
   // have Glibc since it is Glibc that provides the HWCAP[2] in the auxv.
+#define MINIMUM_AIX_OS_MAJOR 7
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nemanjai wrote:

We can probably just make these `constexpr int` variables rather than #defining them.

https://github.com/llvm/llvm-project/pull/80069