[clang] [llvm] [PowerPC][X86] Make cpu id builtins target independent and lower for PPC (PR #68919)

[Nemanja Ivanovic via cfe-commits]

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@@ -210,6 +210,12 @@ let TargetPrefix = "ppc" in {  // All intrinsics start with "llvm.ppc.".
             [llvm_float_ty],
             [llvm_float_ty, llvm_float_ty, llvm_float_ty, llvm_vararg_ty],
             [IntrNoMem]>;
+  // Load of a value provided by the system library at a fixed address. Used for
+  // accessing things like HWCAP word provided by GLIBC.
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nemanjai wrote:

I don't think that comment would make sense any longer now that I have made this intrinsic PPC-specific. This is why I removed it and shortened it. I will put back the PPC-specific portions of the elaborated comment though.

https://github.com/llvm/llvm-project/pull/68919