Rename VAStart -> ImageBase. NFC.

[ruiu]

Summary

Config members are named after corresponding command line options.
This patch renames VAStart ImageBase so that they are in line with
--image-base.

[• rafael]

LGTM

ELF/Config.h

struct Configuration {
   bool ZNow;
   bool ZOrigin;
   bool ZRelro;
   UnresolvedPolicy UnresolvedSymbols;
   BuildIdKind BuildId = BuildIdKind::None;
   ELFKind EKind = ELFNoneKind;
   uint16_t EMachine = llvm::ELF::EM_NONE;
   uint64_t EntryAddr = -1;
-  uint64_t VAStart;
+  uint64_t ImageBase;
   unsigned LtoJobs;
   unsigned LtoO;
   unsigned Optimize;
 };
 
 // The only instance of Configuration struct.
 extern Configuration *Config;
 
 } // namespace elf
 } // namespace lld
 
 #endif

ELF/Driver.cpp

template <class ELFT> void LinkerDriver::link(opt::InputArgList &Args) {
   if (!Config->Entry.empty()) {
     StringRef S = Config->Entry;
     if (S.getAsInteger(0, Config->EntryAddr))
       Config->EntrySym = Symtab.addUndefined(S);
   }
 
   if (auto *Arg = Args.getLastArg(OPT_image_base)) {
     StringRef S = Arg->getValue();
-    if (S.getAsInteger(0, Config->VAStart))
+    if (S.getAsInteger(0, Config->ImageBase))
       error(Arg->getSpelling() + ": number expected, but got " + S);
-    else if ((Config->VAStart % Target->PageSize) != 0)
+    else if ((Config->ImageBase % Target->PageSize) != 0)
       warning(Arg->getSpelling() + ": address isn't multiple of page size");
   } else {
-    Config->VAStart = Target->getVAStart();
+    Config->ImageBase = Target->getImageBase();
   }
 
   for (std::unique_ptr<InputFile> &F : Files)
     Symtab.addFile(std::move(F));
   if (HasError)
     return; // There were duplicate symbols or incompatible files
 
   Symtab.scanUndefinedFlags();

ELF/OutputSections.cpp

template <class ELFT> void DynamicSection<ELFT>::finalize() {
   if (HasVerNeed) {
     Add({DT_VERNEED, Out<ELFT>::VerNeed});
     Add({DT_VERNEEDNUM, Out<ELFT>::VerNeed->getNeedNum()});
   }
 
   if (Config->EMachine == EM_MIPS) {
     Add({DT_MIPS_RLD_VERSION, 1});
     Add({DT_MIPS_FLAGS, RHF_NOTPOT});
-    Add({DT_MIPS_BASE_ADDRESS, (uintX_t)Target->getVAStart()});
+    Add({DT_MIPS_BASE_ADDRESS, (uintX_t)Target->getImageBase()});
     Add({DT_MIPS_SYMTABNO, Out<ELFT>::DynSymTab->getNumSymbols()});
     Add({DT_MIPS_LOCAL_GOTNO, Out<ELFT>::Got->getMipsLocalEntriesNum()});
     if (const SymbolBody *B = Out<ELFT>::Got->getMipsFirstGlobalEntry())
       Add({DT_MIPS_GOTSYM, B->DynsymIndex});
     else
       Add({DT_MIPS_GOTSYM, Out<ELFT>::DynSymTab->getNumSymbols()});
     Add({DT_PLTGOT, Out<ELFT>::Got});
     if (Out<ELFT>::MipsRldMap)

ELF/Target.h

 
 namespace lld {
 namespace elf {
 class InputFile;
 class SymbolBody;
 
 class TargetInfo {
 public:
-  uint64_t getVAStart() const;
+  uint64_t getImageBase() const;
   virtual bool isTlsInitialExecRel(uint32_t Type) const;
   virtual bool isTlsLocalDynamicRel(uint32_t Type) const;
   virtual bool isTlsGlobalDynamicRel(uint32_t Type) const;
   virtual uint32_t getDynRel(uint32_t Type) const { return Type; }
   virtual void writeGotPltHeader(uint8_t *Buf) const {}
   virtual void writeGotPlt(uint8_t *Buf, const SymbolBody &S) const {};
   virtual uint64_t getImplicitAddend(const uint8_t *Buf, uint32_t Type) const;
 
public:
   unsigned PageSize = 4096;
 
   // On freebsd x86_64 the first page cannot be mmaped.
   // On linux that is controled by vm.mmap_min_addr. At least on some x86_64
   // installs that is 65536, so the first 15 pages cannot be used.
   // Given that, the smallest value that can be used in here is 0x10000.
   // If using 2MB pages, the smallest page aligned address that works is
   // 0x200000, but it looks like every OS uses 4k pages for executables.
-  uint64_t VAStart = 0x10000;
+  uint64_t ImageBase = 0x10000;
 
   uint32_t CopyRel;
   uint32_t GotRel;
   uint32_t PltRel;
   uint32_t RelativeRel;
   uint32_t IRelativeRel;
   uint32_t TlsDescRel;
   uint32_t TlsGotRel;

ELF/Target.cpp

 
 TargetInfo::~TargetInfo() {}
 
 uint64_t TargetInfo::getImplicitAddend(const uint8_t *Buf,
                                        uint32_t Type) const {
   return 0;
 }
 
-uint64_t TargetInfo::getVAStart() const { return Config->Pic ? 0 : VAStart; }
+uint64_t TargetInfo::getImageBase() const {
+  return Config->Pic ? 0 : ImageBase;
+}
 
 bool TargetInfo::usesOnlyLowPageBits(uint32_t Type) const { return false; }
 
 RelExpr TargetInfo::getThunkExpr(RelExpr Expr, uint32_t RelocType,
                                  const InputFile &File,
                                  const SymbolBody &S) const {
   return Expr;
 }
PPC64TargetInfo::PPC64TargetInfo() {
   // The PPC64 ELF ABI v1 spec, says:
   //
   //   It is normally desirable to put segments with different characteristics
   //   in separate 256 Mbyte portions of the address space, to give the
   //   operating system full paging flexibility in the 64-bit address space.
   //
   // And because the lowest non-zero 256M boundary is 0x10000000, PPC64 linkers
   // use 0x10000000 as the starting address.
-  VAStart = 0x10000000;
+  ImageBase = 0x10000000;
 }
 
 static uint64_t PPC64TocOffset = 0x8000;
 
 uint64_t getPPC64TocBase() {
   // The TOC consists of sections .got, .toc, .tocbss, .plt in that order. The
   // TOC starts where the first of these sections starts. We always create a
   // .got when we see a relocation that uses it, so for us the start is always

ELF/Writer.cpp

if (needsPtLoad(Sec))
       Sec->PageAlign = true;
   }
 }
 
 // We should set file offsets and VAs for elf header and program headers
 // sections. These are special, we do not include them into output sections
 // list, but have them to simplify the code.
 template <class ELFT> void Writer<ELFT>::fixHeaders() {
-  uintX_t BaseVA = ScriptConfig->DoLayout ? 0 : Config->VAStart;
+  uintX_t BaseVA = ScriptConfig->DoLayout ? 0 : Config->ImageBase;
   Out<ELFT>::ElfHeader->setVA(BaseVA);
   uintX_t Off = Out<ELFT>::ElfHeader->getSize();
   Out<ELFT>::ProgramHeaders->setVA(Off + BaseVA);
 }
 
 // Assign VAs (addresses at run-time) to output sections.
 template <class ELFT> void Writer<ELFT>::assignAddresses() {
-  uintX_t VA = Config->VAStart + Out<ELFT>::ElfHeader->getSize() +
+  uintX_t VA = Config->ImageBase + Out<ELFT>::ElfHeader->getSize() +
                Out<ELFT>::ProgramHeaders->getSize();
 
   uintX_t ThreadBssOffset = 0;
   for (OutputSectionBase<ELFT> *Sec : OutputSections) {
     uintX_t Alignment = Sec->getAlignment();
     if (Sec->PageAlign)
       Alignment = std::max<uintX_t>(Alignment, Target->PageSize);