[gardening] Use proper doxygen comments (///)

include/swift/SIL/SILCloner.h

@@ -379,7 +379,7 @@ SILCloner<ImplClass>::postProcess(SILInstruction *Orig,
   InstructionMap.insert(std::make_pair(Orig, Cloned));
 }
 
-// \brief Recursively visit a callee's BBs in depth-first preorder (only
+/// \brief Recursively visit a callee's BBs in depth-first preorder (only
 /// processing blocks on the first visit), mapping newly visited BBs to new BBs
 /// in the caller and cloning all instructions into the caller other than
 /// terminators which should be handled separately later by subclasses

lib/SILOptimizer/LoopTransforms/COWArrayOpt.cpp

@@ -359,14 +359,14 @@ class COWArrayOpt {
   // make_mutable calls are required within the loop body for that array.
   llvm::SmallDenseMap<SILValue, ApplyInst*> ArrayMakeMutableMap;
 
-  // \brief Transient per-Array user set.
-  //
-  // Track all known array users with the exception of struct_extract users
-  // (checkSafeArrayElementUse prohibits struct_extract users from mutating the
-  // array). During analysis of retains/releases within the loop body, the
-  // users in this set are assumed to cover all possible mutating operations on
-  // the array. If the array escaped through an unknown use, the analysis must
-  // abort earlier.
+  /// \brief Transient per-Array user set.
+  ///
+  /// Track all known array users with the exception of struct_extract users
+  /// (checkSafeArrayElementUse prohibits struct_extract users from mutating the
+  /// array). During analysis of retains/releases within the loop body, the
+  /// users in this set are assumed to cover all possible mutating operations on
+  /// the array. If the array escaped through an unknown use, the analysis must
+  /// abort earlier.
   SmallPtrSet<SILInstruction*, 8> ArrayUserSet;
 
   // When matching retains to releases we must not match the same release twice.
@@ -466,8 +466,8 @@ SmallPtrSetImpl<SILBasicBlock*> &COWArrayOpt::getReachingBlocks() {
 }
 
 
-// \return true if the instruction is a call to a non-mutating array semantic
-// function.
+/// \return true if the instruction is a call to a non-mutating array semantic
+/// function.
 static bool isNonMutatingArraySemanticCall(SILInstruction *Inst) {
   ArraySemanticsCall Call(Inst);
   if (!Call)

lib/Sema/ConstraintSystem.h

@@ -1553,9 +1553,9 @@ class ConstraintSystem {
   void assignFixedType(TypeVariableType *typeVar, Type type,
                        bool updateState = true);
 
-  // \brief Set the TVO_MustBeMaterializable bit on all type variables
-  // necessary to ensure that the type in question is materializable in a
-  // viable solution.
+  /// \brief Set the TVO_MustBeMaterializable bit on all type variables
+  /// necessary to ensure that the type in question is materializable in a
+  /// viable solution.
   void setMustBeMaterializableRecursive(Type type);
 
   /// \brief Determine if the type in question is an Array<T>.