[llvm] [Xtensa] Lowering FRAMEADDR/RETURNADDR operations. (PR #107363)

[Matt Arsenault via llvm-commits]

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@@ -722,6 +743,28 @@ SDValue XtensaTargetLowering::LowerSTACKRESTORE(SDValue Op,
                           Op.getOperand(1));
 }
 
+SDValue XtensaTargetLowering::LowerFRAMEADDR(SDValue Op,
+                                             SelectionDAG &DAG) const {
+  // This nodes represent llvm.frameaddress on the DAG.
+  // It takes one operand, the index of the frame address to return.
+  // An index of zero corresponds to the current function's frame address.
+  // An index of one to the parent's frame address, and so on.
+  // Depths > 0 not supported yet!
+  if (Op.getConstantOperandVal(0) > 0)
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arsenm wrote:

!= 0

https://github.com/llvm/llvm-project/pull/107363