[clang] [llvm] [PowerPC] Add BCDCOPYSIGN and BCDSETSIGN Instruction Support (PR #144874)

[Aditi Medhane via llvm-commits]

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@@ -515,6 +515,10 @@ TARGET_BUILTIN(__builtin_altivec_vctzh, "V8UsV8Us", "", "power9-vector")
 TARGET_BUILTIN(__builtin_altivec_vctzw, "V4UiV4Ui", "", "power9-vector")
 TARGET_BUILTIN(__builtin_altivec_vctzd, "V2ULLiV2ULLi", "", "power9-vector")
 
+//P9 BCD builtins
+TARGET_BUILTIN(__builtin_ppc_bcdcopysign, "V16UcV16UcV16Uc", "", "power9-vector")
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AditiRM wrote:

This is another power9 instruction according to the documentation : [[documentation of XLC compiler](https://www.ibm.com/docs/en/xl-c-and-cpp-aix/16.1.0?topic=end-builtin-bcdcopysign-clang-based-front)]
Since bcdcopysign and bcdsetsign operate on vector types and are specific to Power9, the appropriate feature for these builtins is power9-vector.

https://github.com/llvm/llvm-project/pull/144874