[clang] [PowerPC] Align bcdsetsign Sema validation with other BCD builtins (PR #178121)

[Aditi Medhane via cfe-commits]

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@@ -147,7 +147,14 @@ bool SemaPPC::CheckPPCBuiltinFunctionCall(const TargetInfo &TI,
   switch (BuiltinID) {
   default:
     return false;
-  case PPC::BI__builtin_ppc_bcdsetsign:
+  case PPC::BI__builtin_ppc_bcdsetsign: {
+    // Arg0 must be vector unsigned char
+    if (!IsTypeVecUChar(TheCall->getArg(0)->getType(), 0))
+      return false;
+
+    // Restrict Arg1 constant range (0–1)
+    return SemaRef.BuiltinConstantArgRange(TheCall, 1, 0, 1);
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AditiRM wrote:

For`bcdsetsign`, the second argument is required to be a constant `0 or 1`. Enforcing the [0,1] constant range is sufficient and matches the documented semantics; an explicit unsigned char type check is unnecessary and consistent with prior BCD builtin handling.

https://github.com/llvm/llvm-project/pull/178121