[Transforms] Use std::nullopt instead of None (NFC)

This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated.  The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.

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/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
index 62f0791..6cdd18f 100644
--- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -3267,7 +3267,7 @@ FoldCondBranchOnValueKnownInPredecessorImpl(BranchInst *BI, DomTreeUpdater *DTU,
     MergeBlockIntoPredecessor(EdgeBB, DTU);
 
     // Signal repeat, simplifying any other constants.
-    return None;
+    return std::nullopt;
   }
 
   return false;
@@ -3282,8 +3282,8 @@ static bool FoldCondBranchOnValueKnownInPredecessor(BranchInst *BI,
   do {
     // Note that None means "we changed things, but recurse further."
     Result = FoldCondBranchOnValueKnownInPredecessorImpl(BI, DTU, DL, AC);
-    EverChanged |= Result == None || *Result;
-  } while (Result == None);
+    EverChanged |= Result == std::nullopt || *Result;
+  } while (Result == std::nullopt);
   return EverChanged;
 }
 
@@ -3558,7 +3558,7 @@ shouldFoldCondBranchesToCommonDestination(BranchInst *BI, BranchInst *PBI,
     if (PBITrueProb.isUnknown() || PBITrueProb.getCompl() < Likely)
       return {{Instruction::Or, true}};
   }
-  return None;
+  return std::nullopt;
 }
 
 static bool performBranchToCommonDestFolding(BranchInst *BI, BranchInst *PBI,