[ELF] - Linkerscript: cleanup of LinkerScript<ELFT>::createSections().

[grimar]

Summary

It is becoming harder to update the AddInputSec functor.
I suggest the next cleanup.

[grimar]

ELF/LinkerScript.cpp

261

forgot static, will add if approved.

[evgeny777]

ELF/LinkerScript.cpp

261

Will it be called from anywhere else except lambda?
I suggest making it static for now

[davide]

ELF/LinkerScript.cpp

288

I'm not entirely convinced about this cleanup, but, whatever.
I think this function should be called shouldIncludeSection.

[grimar]

This is depricated one.

ELF/LinkerScript.cpp

 static bool match(StringRef Pattern, ArrayRef<StringRef> Arr) {
   for (StringRef S : Arr)
     if (globMatch(S, Pattern))
       return true;
   return false;
 }
 
 template <class ELFT>
+bool canAddSection(InputSectionBase<ELFT> *C, ConstraintKind Kind) {
+  if (Kind == NoConstraint)
+    return true;
+  bool Writable = C->getSectionHdr()->sh_flags & SHF_WRITE;
+  if (Kind == ReadWrite && !Writable)
+    return false;
+  if (Kind == ReadOnly && Writable)
+    return false;
+  return true;
+}
+
+template <class ELFT>
 std::vector<OutputSectionBase<ELFT> *>
 LinkerScript<ELFT>::createSections(OutputSectionFactory<ELFT> &Factory) {
   typedef const std::unique_ptr<ObjectFile<ELFT>> ObjectFile;
   std::vector<OutputSectionBase<ELFT> *> Result;
   DenseSet<OutputSectionBase<ELFT> *> Removed;
 
   // Add input section to output section. If there is no output section yet,
   // then create it and add to output section list.
   auto AddInputSec = [&](InputSectionBase<ELFT> *C, StringRef Name,
                          ConstraintKind Constraint) {
     OutputSectionBase<ELFT> *Sec;
     bool IsNew;
     std::tie(Sec, IsNew) = Factory.create(C, Name);
     if (IsNew)
       Result.push_back(Sec);
-    if ((!(C->getSectionHdr()->sh_flags & SHF_WRITE)) &&
-        Constraint == ReadWrite) {
-      Removed.insert(Sec);
-      return;
-    }
-    if ((C->getSectionHdr()->sh_flags & SHF_WRITE) && Constraint == ReadOnly) {
+    if (!canAddSection(C, Constraint)) {
       Removed.insert(Sec);
       return;
     }
     Sec->addSection(C);
   };
 
   // Select input sections matching rule and add them to corresponding
   // output section. Section rules are processed in order they're listed