[clang] [llvm] [SystemZ] Add support for __builtin_setjmp and __builtin_longjmp (PR #116642)

[Ulrich Weigand via cfe-commits]

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@@ -6292,6 +6534,10 @@ SDValue SystemZTargetLowering::LowerOperation(SDValue Op,
     return lowerGET_ROUNDING(Op, DAG);
   case ISD::READCYCLECOUNTER:
     return lowerREADCYCLECOUNTER(Op, DAG);
+  case ISD::EH_SJLJ_SETJMP:
+  case ISD::EH_SJLJ_LONGJMP:
+    return Op;
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uweigand wrote:

This comment doesn't look quite right to me.  I think it should say something like:
"These operations are legal on our platform, but we cannot actually set the operation action to Legal as common code would treat this as equivalent to Expand.  Instead, we the operation action to Custom and just leave them unchanged here."

https://github.com/llvm/llvm-project/pull/116642