addressed comments

Author: Alexander Yermolovich

bolt/include/bolt/Core/BinaryContext.h

@@ -277,9 +277,9 @@ class BinaryContext {
 
 public:
   enum class ICFLevel {
-    None,
-    Safe,
-    All,
+    None, // No ICF. (Default)
+    Safe, // Safe ICF for all sections.
+    All,  // Aggressive ICF for code.
   };
   static Expected<std::unique_ptr<BinaryContext>>
   createBinaryContext(Triple TheTriple, StringRef InputFileName,

bolt/include/bolt/Passes/IdenticalCodeFolding.h

@@ -40,10 +40,10 @@ class IdenticalCodeFolding : public BinaryFunctionPass {
   Error runOnFunctions(BinaryContext &BC) override;
 
 private:
-  /// Analyses .text section and relocations and marks functions that are not
+  /// Analyze .text section and relocations and mark functions that are not
   /// safe to fold.
   Error markFunctionsUnsafeToFold(BinaryContext &BC);
-  /// Processes relocations in the .data section to identify function
+  /// Process relocations in the .data section to identify function
   /// references.
   void processDataRelocations(BinaryContext &BC,
                               const SectionRef &SecRefRelData);

bolt/lib/Core/BinaryContext.cpp

@@ -2015,6 +2015,7 @@ static void printDebugInfo(raw_ostream &OS, const MCInst &Instruction,
     OS << " discriminator:" << Row.Discriminator;
 }
 
+/// Skip instructions that are not interesting for safe ICF.
 static bool skipInstruction(const MCInst &Inst, const BinaryContext &BC) {
   const bool IsX86 = BC.isX86();
   return (BC.MIB->isPseudo(Inst) || BC.MIB->isUnconditionalBranch(Inst) ||