[clang] Use std::optional instead of llvm::Optional (NFC)

This patch replaces (llvm::|)Optional< with std::optional<.  I'll post
a separate patch to remove #include "llvm/ADT/Optional.h".

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, 4 insertions, 4 deletions

diff --git a/clang/lib/Analysis/ReachableCode.cpp b/clang/lib/Analysis/ReachableCode.cpp
index a375521..5cc63bb 100644
--- a/clang/lib/Analysis/ReachableCode.cpp
+++ b/clang/lib/Analysis/ReachableCode.cpp
@@ -74,7 +74,7 @@ static bool isBuiltinAssumeFalse(const CFGBlock *B, const Stmt *S,
     // (e.g. a CFGBlock containing only a goto).
     return false;
   }
-  if (Optional<CFGStmt> CS = B->back().getAs<CFGStmt>()) {
+  if (std::optional<CFGStmt> CS = B->back().getAs<CFGStmt>()) {
     if (const auto *CE = dyn_cast<CallExpr>(CS->getStmt())) {
       return CE->getCallee()->IgnoreCasts() == S && CE->isBuiltinAssumeFalse(C);
     }
@@ -89,7 +89,7 @@ static bool isDeadReturn(const CFGBlock *B, const Stmt *S) {
   const CFGBlock *Current = B;
   while (true) {
     for (const CFGElement &CE : llvm::reverse(*Current)) {
-      if (Optional<CFGStmt> CS = CE.getAs<CFGStmt>()) {
+      if (std::optional<CFGStmt> CS = CE.getAs<CFGStmt>()) {
         if (const ReturnStmt *RS = dyn_cast<ReturnStmt>(CS->getStmt())) {
           if (RS == S)
             return true;
@@ -340,7 +340,7 @@ static unsigned scanFromBlock(const CFGBlock *Start,
     // This allows us to potentially uncover some "always unreachable" code
     // within the "sometimes unreachable" code.
     // Look at the successors and mark then reachable.
-    Optional<bool> TreatAllSuccessorsAsReachable;
+    std::optional<bool> TreatAllSuccessorsAsReachable;
     if (!IncludeSometimesUnreachableEdges)
       TreatAllSuccessorsAsReachable = false;
 
@@ -462,7 +462,7 @@ static bool isValidDeadStmt(const Stmt *S) {
 
 const Stmt *DeadCodeScan::findDeadCode(const clang::CFGBlock *Block) {
   for (CFGBlock::const_iterator I = Block->begin(), E = Block->end(); I!=E; ++I)
-    if (Optional<CFGStmt> CS = I->getAs<CFGStmt>()) {
+    if (std::optional<CFGStmt> CS = I->getAs<CFGStmt>()) {
       const Stmt *S = CS->getStmt();
       if (isValidDeadStmt(S))
         return S;