[llvm] [RISCV][CFI] add function epilogue cfi information (PR #110810)

[via llvm-commits]

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@@ -852,14 +879,35 @@ void RISCVFrameLowering::emitEpilogue(MachineFunction &MF,
   // normally it's just checking the variable sized object is present or not
   // is enough, but we also don't preserve that at prologue/epilogue when
   // have vector objects in stack.
-  if (RestoreFP) {
+  if (RestoreSPFromFP) {
     assert(hasFP(MF) && "frame pointer should not have been eliminated");
 
     RI->adjustReg(MBB, LastFrameDestroy, DL, SPReg, FPReg,
                   StackOffset::getFixed(-FPOffset), MachineInstr::FrameDestroy,
                   getStackAlign());
   }
 
+  if (hasFP(MF)) {
+    unsigned CFIIndex = MF.addFrameInst(MCCFIInstruction::cfiDefCfa(
+        nullptr, RI->getDwarfRegNum(SPReg, true), RealStackSize));
+    BuildMI(MBB, LastFrameDestroy, DL, TII->get(TargetOpcode::CFI_INSTRUCTION))
+        .addCFIIndex(CFIIndex)
+        .setMIFlag(MachineInstr::FrameDestroy);
+  }
+
+  if (getLibCallID(MF, CSI) + 1) {
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dlav-sc wrote:

addressed

https://github.com/llvm/llvm-project/pull/110810