[ELF] - Split Writer::assignAddresses(): extract code for initializing dummies sections

[grimar]

Summary

Extracts code for initializing dummies sections
to avoid possible duplication in following patches.

[ruiu]

ELF/Writer.cpp

1377

This line does not depend on any data we have created until the control reaches this point. Move this to writeResult.

1378–1379

Then you can move this at end of createPhdrs.

[grimar]

• Addressed review comments.

[ruiu]

I cleaned up this part of the Writer, so please rebase to head and upload the patch again. Thanks.

[grimar]

In D18691#389584, @ruiu wrote:

I cleaned up this part of the Writer, so please rebase to head and upload the patch again. Thanks.

Ok. Btw there is a empty fixFileOff() now left in code.

[grimar]

• Rebased

[ruiu]

LGTM with a few nits.

ELF/Writer.cpp

209

Please move this after

OutputSectionBase<ELFT> ElfHeader("", 0, SHF_ALLOC);

1339–1340

Out<ELFT>::ProgramHeaders->setSize(sizeof(Elf_Phdr) * Phdrs.size());

[grimar]

In D18691#389604, @ruiu wrote:

LGTM with a few nits.

Ok, thanks for review. I am planning to rebase/update D18499 now with this all changes.

[grimar]

r265159

ELF/Writer.cpp

private:
   // Flag to force GOT to be in output if we have relocations
   // that relies on its address.
   bool HasGotOffRel = false;
 };
 } // anonymous namespace
 
 template <class ELFT> void elf::writeResult(SymbolTable<ELFT> *Symtab) {
   typedef typename ELFT::uint uintX_t;
+  typedef typename ELFT::Ehdr Elf_Ehdr;
 
   // Create singleton output sections.
   DynamicSection<ELFT> Dynamic(*Symtab);
   EhFrameHeader<ELFT> EhFrameHdr;
   GotSection<ELFT> Got;
   InterpSection<ELFT> Interp;
   PltSection<ELFT> Plt;
   RelocationSection<ELFT> RelaDyn(Config->Rela ? ".rela.dyn" : ".rel.dyn");
template <class ELFT> void elf::writeResult(SymbolTable<ELFT> *Symtab) {
   Out<ELFT>::SymTab = SymTabSec.get();
   Out<ELFT>::Bss = nullptr;
   Out<ELFT>::MipsRldMap = MipsRldMap.get();
   Out<ELFT>::Opd = nullptr;
   Out<ELFT>::OpdBuf = nullptr;
   Out<ELFT>::TlsPhdr = nullptr;
   Out<ELFT>::ElfHeader = &ElfHeader;
   Out<ELFT>::ProgramHeaders = &ProgramHeaders;
+  Out<ELFT>::ElfHeader->setSize(sizeof(Elf_Ehdr));
 
   Writer<ELFT>(*Symtab).run();
 }
 
 // The main function of the writer.
 template <class ELFT> void Writer<ELFT>::run() {
   if (!Config->DiscardAll)
     copyLocalSymbols();
template <class ELFT> void Writer<ELFT>::createPhdrs() {
 
   // PT_GNU_STACK is a special section to tell the loader to make the
   // pages for the stack non-executable.
   if (!Config->ZExecStack)
     AddHdr(PT_GNU_STACK, PF_R | PF_W);
 
   if (Note.First)
     Phdrs.push_back(std::move(Note));
+
+  size_t PhdrSize = sizeof(Elf_Phdr) * Phdrs.size();
+  Out<ELFT>::ProgramHeaders->setSize(PhdrSize);
 }
 
 // The first section of each PT_LOAD and the first section after PT_GNU_RELRO
 // have to be page aligned so that the dynamic linker can set the permissions.
 template <class ELFT> void Writer<ELFT>::fixSectionAlignments() {
   for (const Phdr &P : Phdrs)
     if (P.H.p_type == PT_LOAD)
       P.First->PageAlign = true;
if (Sec->getType() != SHT_NOBITS)
     FileOff = alignTo(FileOff, Align);
   Sec->setFileOffset(FileOff);
   if (Sec->getType() != SHT_NOBITS)
     FileOff += Sec->getSize();
   return FileOff;
 }
 
 // Used for relocatable output (-r). In this case we create only ELF file
 // header, do not create program headers. Also assign of section addresses
 // is very straightforward: we just put all sections sequentually to the file.
 template <class ELFT> void Writer<ELFT>::assignAddressesRelocatable() {
-  Out<ELFT>::ElfHeader->setSize(sizeof(Elf_Ehdr));
   uintX_t FileOff = 0;
   for (OutputSectionBase<ELFT> *Sec : OutputSections)
     FileOff = fixFileOff(FileOff, Sec->getAlign(), Sec);
   SectionHeaderOff = alignTo(FileOff, sizeof(uintX_t));
   FileSize = SectionHeaderOff + getNumSections() * sizeof(Elf_Shdr);
 }
 
 // Visits all headers in PhdrTable and assigns the adresses to
 // the output sections. Also creates common and special headers.
 template <class ELFT> void Writer<ELFT>::assignAddresses() {
-  Out<ELFT>::ElfHeader->setSize(sizeof(Elf_Ehdr));
-  size_t PhdrSize = sizeof(Elf_Phdr) * Phdrs.size();
-  Out<ELFT>::ProgramHeaders->setSize(PhdrSize);
-
   uintX_t ThreadBssOffset = 0;
   uintX_t VA = Target->getVAStart();
   uintX_t FileOff = 0;
 
   for (OutputSectionBase<ELFT> *Sec : OutputSections) {
     uintX_t Align = Sec->getAlign();
     if (Sec->PageAlign)
       Align = std::max<uintX_t>(Align, Target->PageSize);