Reduce code duplication a bit

[ruiu]

LGTM

[grimar]

LGTM.

[grimar]

I think the same simplification can be used for code added in r328419.

[• espindola]

328569

ELF/InputSection.cpp

template <class ELFT> void InputSection::copyShtGroup(uint8_t *Buf) {
   // Adjust section numbers because section numbers in an input object
   // files are different in the output.
   ArrayRef<InputSectionBase *> Sections = File->getSections();
   for (uint32_t Idx : From.slice(1))
     *To++ = Sections[Idx]->getOutputSection()->SectionIndex;
 }
 
 InputSectionBase *InputSection::getRelocatedSection() {
-  assert(Type == SHT_RELA || Type == SHT_REL);
+  if (!File || (Type != SHT_RELA && Type != SHT_REL))
+    return nullptr;
   ArrayRef<InputSectionBase *> Sections = File->getSections();
   return Sections[Info];
 }
 
 // This is used for -r and --emit-relocs. We can't use memcpy to copy
 // relocations because we need to update symbol table offset and section index
 // for each relocation. So we copy relocations one by one.
 template <class ELFT, class RelTy>

ELF/LinkerScript.cpp

auto Add = [&](InputSectionBase *S) {
     assert(S->getOutputSection()->SectionIndex == UINT32_MAX);
   };
 
   // For futher --emit-reloc handling code we need target output section
   // to be created before we create relocation output section, so we want
   // to create target sections first. We do not want priority handling
   // for synthetic sections because them are special.
   for (InputSectionBase *IS : InputSections) {
-    if ((IS->Type == SHT_REL || IS->Type == SHT_RELA) &&
-        !isa<SyntheticSection>(IS))
-      if (auto *Rel = cast<InputSection>(IS)->getRelocatedSection())
+    if (auto *Sec = dyn_cast<InputSection>(IS))
+      if (InputSectionBase *Rel = Sec->getRelocatedSection())
         if (auto *RelIS = dyn_cast_or_null<InputSectionBase>(Rel->Parent))
           Add(RelIS);
     Add(IS);
   }
 
   // If no SECTIONS command was given, we should insert sections commands
   // before others, so that we can handle scripts which refers them,
   // for example: "foo = ABSOLUTE(ADDR(.text)));".

ELF/Writer.cpp

 
 StringRef elf::getOutputSectionName(InputSectionBase *S) {
   if (Config->Relocatable)
     return S->Name;
 
   // This is for --emit-relocs. If .text.foo is emitted as .text.bar, we want
   // to emit .rela.text.foo as .rela.text.bar for consistency (this is not
   // technically required, but not doing it is odd). This code guarantees that.
-  if ((S->Type == SHT_REL || S->Type == SHT_RELA) &&
-      !isa<SyntheticSection>(S)) {
-    OutputSection *Out =
-        cast<InputSection>(S)->getRelocatedSection()->getOutputSection();
+  if (auto *IS = dyn_cast<InputSection>(S)) {
+    if (InputSectionBase *Rel = IS->getRelocatedSection()) {
+      OutputSection *Out = Rel->getOutputSection();
       if (S->Type == SHT_RELA)
         return Saver.save(".rela" + Out->Name);
       return Saver.save(".rel" + Out->Name);
     }
+  }
 
   for (StringRef V :
        {".text.", ".rodata.", ".data.rel.ro.", ".data.", ".bss.rel.ro.",
         ".bss.", ".init_array.", ".fini_array.", ".ctors.", ".dtors.", ".tbss.",
         ".gcc_except_table.", ".tdata.", ".ARM.exidx.", ".ARM.extab."}) {
     StringRef Prefix = V.drop_back();
     if (S->Name.startswith(V) || S->Name == Prefix)
       return Prefix;