[clang] [llvm] [PowerPC] Support for Packed BCD conversion builtins (PR #142723)

[Lei Huang via llvm-commits]

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@@ -567,6 +567,13 @@ TARGET_BUILTIN(__builtin_altivec_vextsh2w, "V4SiV8Ss", "", "power9-vector")
 TARGET_BUILTIN(__builtin_altivec_vextsh2d, "V2SLLiV8Ss", "", "power9-vector")
 TARGET_BUILTIN(__builtin_altivec_vextsw2d, "V2SLLiV4Si", "", "power9-vector")
 
+// P9 BCD builtins (the signature used here is for informational purposes only
+// as front-end emits custom codegens for these set of builtins.)                                                    
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lei137 wrote:

Let's keep this general and have a section for all BCD builtins here.
```suggestion
// P9 Binary-coded decimal (BCD) builtins.
```

https://github.com/llvm/llvm-project/pull/142723