[llvm] Xtensa] Implement windowed call ABI. (PR #130001)

[Matt Arsenault via llvm-commits]

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@@ -944,9 +946,11 @@ SDValue XtensaTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
   SDValue SP = DAG.getCopyFromReg(Chain, DL, SPReg, VT);
   SDValue NewSP = DAG.getNode(ISD::SUB, DL, VT, SP, SizeRoundUp); // Value
   if (Subtarget.isWindowedABI()) {
-    NewSP = DAG.getNode(XtensaISD::MOVSP, DL, MVT::i32, NewSP);
+    Chain = DAG.getNode(XtensaISD::MOVSP, SDLoc(Op), MVT::Other, SP.getValue(1),
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arsenm wrote:

Should this be using the call frame pseudos like other targets? As is I think this will miss setting MachineFrameInfo's AdjustsStack 

https://github.com/llvm/llvm-project/pull/130001