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

[Amy Kwan via cfe-commits]

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@@ -16542,12 +16542,64 @@ Value *CodeGenFunction::EmitPPCBuiltinExpr(unsigned BuiltinID,
 
   Intrinsic::ID ID = Intrinsic::not_intrinsic;
 
+  // The lambda function converts builtin_cpu_is function into directly
+  // returning false or true, or it gets and checks the information from the
+  // kernel variable _system_configuration for AIX OS.
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amy-kwan wrote:

```suggestion
  // This lambda function converts __builtin_cpu_is() into directly
  // returning true or false, or it gets and checks the information from the
  // kernel variable _system_configuration from the AIX OS.
```
I'm not sure if this wording sounds better or more accurate, so we can change this but basically I think we can update this comment a bit more so that it makes more sense.


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