[llvm] [Xtensa] Implement volatile load/store. (PR #110292)

[Andrei Safronov via llvm-commits]

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@@ -1104,10 +1104,24 @@ XtensaTargetLowering::emitSelectCC(MachineInstr &MI,
 MachineBasicBlock *XtensaTargetLowering::EmitInstrWithCustomInserter(
     MachineInstr &MI, MachineBasicBlock *MBB) const {
   DebugLoc DL = MI.getDebugLoc();
+  const TargetInstrInfo &TII = *Subtarget.getInstrInfo();
 
   switch (MI.getOpcode()) {
   case Xtensa::SELECT:
     return emitSelectCC(MI, MBB);
+  case Xtensa::S8I:
+  case Xtensa::S16I:
+  case Xtensa::S32I:
+  case Xtensa::L8UI:
+  case Xtensa::L16SI:
+  case Xtensa::L16UI:
+  case Xtensa::L32I: {
+    const MachineMemOperand &MMO = **MI.memoperands_begin();
+    if (MMO.isVolatile()) {
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andreisfr wrote:

I added handling of the case when MMO is missing.

https://github.com/llvm/llvm-project/pull/110292