[CodeGen] Use std::optional in SafeStack.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

1 files changed, 2 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/SafeStack.cpp b/llvm/lib/CodeGen/SafeStack.cpp
index 0e65a0b..bcad7a3 100644
--- a/llvm/lib/CodeGen/SafeStack.cpp
+++ b/llvm/lib/CodeGen/SafeStack.cpp
@@ -67,6 +67,7 @@
 #include <algorithm>
 #include <cassert>
 #include <cstdint>
+#include <optional>
 #include <string>
 #include <utility>
 
@@ -896,7 +897,7 @@ public:
 
     DominatorTree *DT;
     bool ShouldPreserveDominatorTree;
-    Optional<DominatorTree> LazilyComputedDomTree;
+    std::optional<DominatorTree> LazilyComputedDomTree;
 
     // Do we already have a DominatorTree avaliable from the previous pass?
     // Note that we should *NOT* require it, to avoid the case where we end up