[clang] [llvm] [ARM] Add support for Windows SEH (PR #184953)

[Eli Friedman via cfe-commits]

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@@ -3838,6 +3838,23 @@ ARMTargetLowering::LowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG,
   SDLoc dl(Op);
   switch (IntNo) {
   default: return SDValue();    // Don't custom lower most intrinsics.
+  case Intrinsic::localaddress: {
+    const MachineFunction &MF = DAG.getMachineFunction();
+    const TargetRegisterInfo *RegInfo = Subtarget->getRegisterInfo();
+    unsigned Reg = RegInfo->getFrameRegister(MF);
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efriedma-quic wrote:

getFrameRegister() here looks suspicious, comparing to other architectures.

https://github.com/llvm/llvm-project/pull/184953