[ELF] Internalize computeCacheDirectedSortOrder. NFC

and delete an incorremtn comment about ctx.arg.callGraphProfile

Author: MaskRay

lld/ELF/CallGraphSort.cpp

@@ -276,8 +276,8 @@ DenseMap<const InputSectionBase *, int> CallGraphSort::run() {
 // Sort sections by the profile data using the Cache-Directed Sort algorithm.
 // The placement is done by optimizing the locality by co-locating frequently
 // executed code sections together.
-DenseMap<const InputSectionBase *, int>
-elf::computeCacheDirectedSortOrder(Ctx &ctx) {
+static DenseMap<const InputSectionBase *, int>
+computeCacheDirectedSortOrder(Ctx &ctx) {
   SmallVector<uint64_t, 0> funcSizes;
   SmallVector<uint64_t, 0> funcCounts;
   SmallVector<codelayout::EdgeCount, 0> callCounts;

lld/ELF/CallGraphSort.h

@@ -15,9 +15,6 @@ namespace lld::elf {
 struct Ctx;
 class InputSectionBase;
 
-llvm::DenseMap<const InputSectionBase *, int>
-computeCacheDirectedSortOrder(Ctx &);
-
 llvm::DenseMap<const InputSectionBase *, int>
 computeCallGraphProfileOrder(Ctx &);
 } // namespace lld::elf

lld/ELF/Writer.cpp

@@ -1083,7 +1083,6 @@ static void maybeShuffle(Ctx &ctx,
 // Builds section order for handling --symbol-ordering-file.
 static DenseMap<const InputSectionBase *, int> buildSectionOrder(Ctx &ctx) {
   DenseMap<const InputSectionBase *, int> sectionOrder;
-  // Use the rarely used option --call-graph-ordering-file to sort sections.
   if (!ctx.arg.callGraphProfile.empty())
     return computeCallGraphProfileOrder(ctx);