[AArch64] Use std::optional in AArch64FrameLowering.cpp (NFC)

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716

diff --git a/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp b/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
index ba325a5..3a85cfe 100644 (file)
--- a/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
@@ -228,6 +228,7 @@
 #include <cassert>
 #include <cstdint>
 #include <iterator>
+#include <optional>
 #include <vector>
 
 using namespace llvm;
@@ -3392,7 +3393,7 @@ class TagStoreEdit {
   StackOffset FrameRegOffset;
   int64_t Size;
   // If not None, move FrameReg to (FrameReg + FrameRegUpdate) at the end.
-  Optional<int64_t> FrameRegUpdate;
+  std::optional<int64_t> FrameRegUpdate;
   // MIFlags for any FrameReg updating instructions.
   unsigned FrameRegUpdateFlags;
 
@@ -3734,7 +3735,7 @@ MachineBasicBlock::iterator tryMergeAdjacentSTG(MachineBasicBlock::iterator II,
   // Find contiguous runs of tagged memory and emit shorter instruction
   // sequencies for them when possible.
   TagStoreEdit TSE(MBB, FirstZeroData);
-  Optional<int64_t> EndOffset;
+  std::optional<int64_t> EndOffset;
   for (auto &Instr : Instrs) {
     if (EndOffset && *EndOffset != Instr.Offset) {
       // Found a gap.