[llvm] [PATCH] [Xtensa] Implement FrameLowering methods and stack operation lowering. (PR #92960)

[Matt Arsenault via llvm-commits]

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@@ -33,10 +33,158 @@ bool XtensaFrameLowering::hasFP(const MachineFunction &MF) const {
 }
 
 void XtensaFrameLowering::emitPrologue(MachineFunction &MF,
-                                       MachineBasicBlock &MBB) const {}
+                                       MachineBasicBlock &MBB) const {
+  assert(&MBB == &MF.front() && "Shrink-wrapping not yet implemented");
+  MachineFrameInfo &MFI = MF.getFrameInfo();
+  const XtensaRegisterInfo *RegInfo = static_cast<const XtensaRegisterInfo *>(
+      MF.getSubtarget().getRegisterInfo());
+  const XtensaInstrInfo &TII =
+      *static_cast<const XtensaInstrInfo *>(MF.getSubtarget().getInstrInfo());
+  MachineBasicBlock::iterator MBBI = MBB.begin();
+  DebugLoc DL = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
+  unsigned SP = Xtensa::SP;
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arsenm wrote:

Use MCRegister 

https://github.com/llvm/llvm-project/pull/92960