[clang] [Clang] Add __builtin_bswapg (PR #162433)

[Alexander Richardson via cfe-commits]

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@@ -14030,6 +13982,15 @@ bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
 
     return Success(Val.reverseBits(), E);
   }
+  case Builtin::BI__builtin_bswapg: {
+    APSInt Val;
+    if (!EvaluateInteger(E->getArg(0), Val, Info))
+      return false;
+    if (Val.getBitWidth() == 8)
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arichardson wrote:

merge this with the switch case below?

https://github.com/llvm/llvm-project/pull/162433