[clang] [llvm] [PowerPC] Add AMO load builtins for conditional increment/decrement (PR #169435)

[Lei Huang via cfe-commits]

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@@ -281,6 +285,21 @@ bool SemaPPC::CheckPPCBuiltinFunctionCall(const TargetInfo &TI,
            << toString(Result, 10) << (IsUnsigned ? "0-4, 6" : "0, 5, 7") << "8"
            << Arg->getSourceRange();
   }
+  case PPC::BI__builtin_amo_lwat_cond:
+  case PPC::BI__builtin_amo_ldat_cond:
+  case PPC::BI__builtin_amo_lwat_cond_s:
+  case PPC::BI__builtin_amo_ldat_cond_s: {
+    llvm::APSInt Result;
+    if (SemaRef.BuiltinConstantArg(TheCall, 1, Result))
+      return true;
+    unsigned Val = Result.getZExtValue();
+    if (llvm::is_contained({24u, 25u, 28u}, Val))
+      return false;
----------------
lei137 wrote:

Yes, so the function would basically test a `val` to a given `list` and error if it's not in the list.  The message that the value is not `in the range` confused me originally.  Maybe it's better in this case to create a new error to indicate we are checking a valid list of values instead of a range?  But I am okay with that being in a follow up patch since I also feel these cases for amo should be place above the section where we are dealing with CUSTOM_BUILTINs .  I think I left that comment on a previous patch but not sure if you saw that.

https://github.com/llvm/llvm-project/pull/169435