Don't iterate over all sections in the ELFFile constructor.

[oota-llvm.git] / include / llvm / Object / ELFObjectFile.h

diff --git a/include/llvm/Object/ELFObjectFile.h b/include/llvm/Object/ELFObjectFile.h
index 633211e056f6b5c45239747627d7c39b450b2225..3a9739afbeba76b6b97cf2056db118ffb59866e0 100644 (file)
--- a/include/llvm/Object/ELFObjectFile.h
+++ b/include/llvm/Object/ELFObjectFile.h
@@ -193,6 +193,8 @@ protected:
   ELFFile<ELFT> EF;
 
   const Elf_Shdr *DotDynSymSec = nullptr; // Dynamic symbol table section.
+  const Elf_Shdr *DotSymtabSec = nullptr; // Symbol table section.
+  ArrayRef<Elf_Word> ShndxTable;
 
   void moveSymbolNext(DataRefImpl &Symb) const override;
   ErrorOr<StringRef> getSymbolName(DataRefImpl Symb) const override;
@@ -204,7 +206,8 @@ protected:
   uint8_t getSymbolOther(DataRefImpl Symb) const override;
   uint8_t getSymbolELFType(DataRefImpl Symb) const override;
   SymbolRef::Type getSymbolType(DataRefImpl Symb) const override;
-  ErrorOr<section_iterator> getSymbolSection(const Elf_Sym *Symb) const;
+  ErrorOr<section_iterator> getSymbolSection(const Elf_Sym *Symb,
+                                             const Elf_Shdr *SymTab) const;
   ErrorOr<section_iterator> getSymbolSection(DataRefImpl Symb) const override;
 
   void moveSectionNext(DataRefImpl &Sec) const override;
@@ -239,10 +242,6 @@ protected:
     return *EF.getSection(Rel.d.a);
   }
 
-  const Elf_Sym *toELFSymIter(DataRefImpl Sym) const {
-    return EF.template getEntry<Elf_Sym>(Sym.d.a, Sym.d.b);
-  }
-
   DataRefImpl toDRI(const Elf_Shdr *SymTable, unsigned SymbolNum) const {
     DataRefImpl DRI;
     if (!SymTable) {
@@ -303,7 +302,13 @@ public:
   const Elf_Rel *getRel(DataRefImpl Rel) const;
   const Elf_Rela *getRela(DataRefImpl Rela) const;
 
-  const Elf_Sym *getSymbol(DataRefImpl Symb) const;
+  const Elf_Sym *getSymbol(DataRefImpl Sym) const {
+    return EF.template getEntry<Elf_Sym>(Sym.d.a, Sym.d.b);
+  }
+
+  const Elf_Shdr *getSection(DataRefImpl Sec) const {
+    return reinterpret_cast<const Elf_Shdr *>(Sec.p);
+  }
 
   basic_symbol_iterator symbol_begin_impl() const override;
   basic_symbol_iterator symbol_end_impl() const override;
@@ -350,7 +355,7 @@ void ELFObjectFile<ELFT>::moveSymbolNext(DataRefImpl &Sym) const {
 
 template <class ELFT>
 ErrorOr<StringRef> ELFObjectFile<ELFT>::getSymbolName(DataRefImpl Sym) const {
-  const Elf_Sym *ESym = toELFSymIter(Sym);
+  const Elf_Sym *ESym = getSymbol(Sym);
   const Elf_Shdr *SymTableSec = *EF.getSection(Sym.d.a);
   const Elf_Shdr *StringTableSec = *EF.getSection(SymTableSec->sh_link);
   StringRef SymTable = *EF.getStringTable(StringTableSec);
@@ -359,12 +364,12 @@ ErrorOr<StringRef> ELFObjectFile<ELFT>::getSymbolName(DataRefImpl Sym) const {
 
 template <class ELFT>
 uint64_t ELFObjectFile<ELFT>::getSectionFlags(DataRefImpl Sec) const {
-  return toELFShdrIter(Sec)->sh_flags;
+  return getSection(Sec)->sh_flags;
 }
 
 template <class ELFT>
 uint32_t ELFObjectFile<ELFT>::getSectionType(DataRefImpl Sec) const {
-  return toELFShdrIter(Sec)->sh_type;
+  return getSection(Sec)->sh_type;
 }
 
 template <class ELFT>
@@ -396,9 +401,11 @@ ELFObjectFile<ELFT>::getSymbolAddress(DataRefImpl Symb) const {
   }
 
   const Elf_Ehdr *Header = EF.getHeader();
+  const Elf_Shdr *SymTab = *EF.getSection(Symb.d.a);
 
   if (Header->e_type == ELF::ET_REL) {
-    ErrorOr<const Elf_Shdr *> SectionOrErr = EF.getSection(ESym);
+    ErrorOr<const Elf_Shdr *> SectionOrErr =
+        EF.getSection(ESym, SymTab, ShndxTable);
     if (std::error_code EC = SectionOrErr.getError())
       return EC;
     const Elf_Shdr *Section = *SectionOrErr;
@@ -411,7 +418,7 @@ ELFObjectFile<ELFT>::getSymbolAddress(DataRefImpl Symb) const {
 
 template <class ELFT>
 uint32_t ELFObjectFile<ELFT>::getSymbolAlignment(DataRefImpl Symb) const {
-  const Elf_Sym *Sym = toELFSymIter(Symb);
+  const Elf_Sym *Sym = getSymbol(Symb);
   if (Sym->st_shndx == ELF::SHN_COMMON)
     return Sym->st_value;
   return 0;
@@ -419,22 +426,22 @@ uint32_t ELFObjectFile<ELFT>::getSymbolAlignment(DataRefImpl Symb) const {
 
 template <class ELFT>
 uint64_t ELFObjectFile<ELFT>::getSymbolSize(DataRefImpl Sym) const {
-  return toELFSymIter(Sym)->st_size;
+  return getSymbol(Sym)->st_size;
 }
 
 template <class ELFT>
 uint64_t ELFObjectFile<ELFT>::getCommonSymbolSizeImpl(DataRefImpl Symb) const {
-  return toELFSymIter(Symb)->st_size;
+  return getSymbol(Symb)->st_size;
 }
 
 template <class ELFT>
 uint8_t ELFObjectFile<ELFT>::getSymbolOther(DataRefImpl Symb) const {
-  return toELFSymIter(Symb)->st_other;
+  return getSymbol(Symb)->st_other;
 }
 
 template <class ELFT>
 uint8_t ELFObjectFile<ELFT>::getSymbolELFType(DataRefImpl Symb) const {
-  return toELFSymIter(Symb)->getType();
+  return getSymbol(Symb)->getType();
 }
 
 template <class ELFT>
@@ -461,7 +468,7 @@ SymbolRef::Type ELFObjectFile<ELFT>::getSymbolType(DataRefImpl Symb) const {
 
 template <class ELFT>
 uint32_t ELFObjectFile<ELFT>::getSymbolFlags(DataRefImpl Sym) const {
-  const Elf_Sym *ESym = toELFSymIter(Sym);
+  const Elf_Sym *ESym = getSymbol(Sym);
 
   uint32_t Result = SymbolRef::SF_None;
 
@@ -475,7 +482,7 @@ uint32_t ELFObjectFile<ELFT>::getSymbolFlags(DataRefImpl Sym) const {
     Result |= SymbolRef::SF_Absolute;
 
   if (ESym->getType() == ELF::STT_FILE || ESym->getType() == ELF::STT_SECTION ||
-      ESym == EF.symbol_begin(EF.getDotSymtabSec()) ||
+      ESym == EF.symbol_begin(DotSymtabSec) ||
       ESym == EF.symbol_begin(DotDynSymSec))
     Result |= SymbolRef::SF_FormatSpecific;
 
@@ -505,8 +512,9 @@ uint32_t ELFObjectFile<ELFT>::getSymbolFlags(DataRefImpl Sym) const {
 
 template <class ELFT>
 ErrorOr<section_iterator>
-ELFObjectFile<ELFT>::getSymbolSection(const Elf_Sym *ESym) const {
-  ErrorOr<const Elf_Shdr *> ESecOrErr = EF.getSection(ESym);
+ELFObjectFile<ELFT>::getSymbolSection(const Elf_Sym *ESym,
+                                      const Elf_Shdr *SymTab) const {
+  ErrorOr<const Elf_Shdr *> ESecOrErr = EF.getSection(ESym, SymTab, ShndxTable);
   if (std::error_code EC = ESecOrErr.getError())
     return EC;
 
@@ -522,19 +530,21 @@ ELFObjectFile<ELFT>::getSymbolSection(const Elf_Sym *ESym) const {
 template <class ELFT>
 ErrorOr<section_iterator>
 ELFObjectFile<ELFT>::getSymbolSection(DataRefImpl Symb) const {
-  return getSymbolSection(getSymbol(Symb));
+  const Elf_Sym *Sym = getSymbol(Symb);
+  const Elf_Shdr *SymTab = *EF.getSection(Symb.d.a);
+  return getSymbolSection(Sym, SymTab);
 }
 
 template <class ELFT>
 void ELFObjectFile<ELFT>::moveSectionNext(DataRefImpl &Sec) const {
-  const Elf_Shdr *ESec = toELFShdrIter(Sec);
+  const Elf_Shdr *ESec = getSection(Sec);
   Sec = toDRI(++ESec);
 }
 
 template <class ELFT>
 std::error_code ELFObjectFile<ELFT>::getSectionName(DataRefImpl Sec,
                                                     StringRef &Result) const {
-  ErrorOr<StringRef> Name = EF.getSectionName(&*toELFShdrIter(Sec));
+  ErrorOr<StringRef> Name = EF.getSectionName(&*getSection(Sec));
   if (!Name)
     return Name.getError();
   Result = *Name;
@@ -543,50 +553,50 @@ std::error_code ELFObjectFile<ELFT>::getSectionName(DataRefImpl Sec,
 
 template <class ELFT>
 uint64_t ELFObjectFile<ELFT>::getSectionAddress(DataRefImpl Sec) const {
-  return toELFShdrIter(Sec)->sh_addr;
+  return getSection(Sec)->sh_addr;
 }
 
 template <class ELFT>
 uint64_t ELFObjectFile<ELFT>::getSectionSize(DataRefImpl Sec) const {
-  return toELFShdrIter(Sec)->sh_size;
+  return getSection(Sec)->sh_size;
 }
 
 template <class ELFT>
 std::error_code
 ELFObjectFile<ELFT>::getSectionContents(DataRefImpl Sec,
                                         StringRef &Result) const {
-  const Elf_Shdr *EShdr = toELFShdrIter(Sec);
+  const Elf_Shdr *EShdr = getSection(Sec);
   Result = StringRef((const char *)base() + EShdr->sh_offset, EShdr->sh_size);
   return std::error_code();
 }
 
 template <class ELFT>
 uint64_t ELFObjectFile<ELFT>::getSectionAlignment(DataRefImpl Sec) const {
-  return toELFShdrIter(Sec)->sh_addralign;
+  return getSection(Sec)->sh_addralign;
 }
 
 template <class ELFT>
 bool ELFObjectFile<ELFT>::isSectionText(DataRefImpl Sec) const {
-  return toELFShdrIter(Sec)->sh_flags & ELF::SHF_EXECINSTR;
+  return getSection(Sec)->sh_flags & ELF::SHF_EXECINSTR;
 }
 
 template <class ELFT>
 bool ELFObjectFile<ELFT>::isSectionData(DataRefImpl Sec) const {
-  const Elf_Shdr *EShdr = toELFShdrIter(Sec);
+  const Elf_Shdr *EShdr = getSection(Sec);
   return EShdr->sh_flags & (ELF::SHF_ALLOC | ELF::SHF_WRITE) &&
          EShdr->sh_type == ELF::SHT_PROGBITS;
 }
 
 template <class ELFT>
 bool ELFObjectFile<ELFT>::isSectionBSS(DataRefImpl Sec) const {
-  const Elf_Shdr *EShdr = toELFShdrIter(Sec);
+  const Elf_Shdr *EShdr = getSection(Sec);
   return EShdr->sh_flags & (ELF::SHF_ALLOC | ELF::SHF_WRITE) &&
          EShdr->sh_type == ELF::SHT_NOBITS;
 }
 
 template <class ELFT>
 bool ELFObjectFile<ELFT>::isSectionVirtual(DataRefImpl Sec) const {
-  return toELFShdrIter(Sec)->sh_type == ELF::SHT_NOBITS;
+  return getSection(Sec)->sh_type == ELF::SHT_NOBITS;
 }
 
 template <class ELFT>
@@ -633,7 +643,7 @@ ELFObjectFile<ELFT>::getRelocatedSection(DataRefImpl Sec) const {
   if (EF.getHeader()->e_type != ELF::ET_REL)
     return section_end();
 
-  const Elf_Shdr *EShdr = toELFShdrIter(Sec);
+  const Elf_Shdr *EShdr = getSection(Sec);
   uintX_t Type = EShdr->sh_type;
   if (Type != ELF::SHT_REL && Type != ELF::SHT_RELA)
     return section_end();
@@ -667,7 +677,7 @@ ELFObjectFile<ELFT>::getRelocationSymbol(DataRefImpl Rel) const {
   if (IsDyn)
     SymbolData = toDRI(DotDynSymSec, symbolIdx);
   else
-    SymbolData = toDRI(EF.getDotSymtabSec(), symbolIdx);
+    SymbolData = toDRI(DotSymtabSec, symbolIdx);
   return symbol_iterator(SymbolRef(SymbolData, this));
 }
 
@@ -711,12 +721,6 @@ ELFObjectFile<ELFT>::getRelocationAddend(DataRefImpl Rel) const {
   return (int64_t)getRela(Rel)->r_addend;
 }
 
-template <class ELFT>
-const typename ELFFile<ELFT>::Elf_Sym *
-ELFObjectFile<ELFT>::getSymbol(DataRefImpl Symb) const {
-  return &*toELFSymIter(Symb);
-}
-
 template <class ELFT>
 const typename ELFObjectFile<ELFT>::Elf_Rel *
 ELFObjectFile<ELFT>::getRel(DataRefImpl Rel) const {
@@ -750,19 +754,35 @@ ELFObjectFile<ELFT>::ELFObjectFile(MemoryBufferRef Object, std::error_code &EC)
       DotDynSymSec = &Sec;
       break;
     }
+    case ELF::SHT_SYMTAB: {
+      if (DotSymtabSec) {
+        // More than one .dynsym!
+        EC = object_error::parse_failed;
+        return;
+      }
+      DotSymtabSec = &Sec;
+      break;
+    }
+    case ELF::SHT_SYMTAB_SHNDX: {
+      ErrorOr<ArrayRef<Elf_Word>> TableOrErr = EF.getSHNDXTable(Sec);
+      if ((EC = TableOrErr.getError()))
+        return;
+      ShndxTable = *TableOrErr;
+      break;
+    }
     }
   }
 }
 
 template <class ELFT>
 basic_symbol_iterator ELFObjectFile<ELFT>::symbol_begin_impl() const {
-  DataRefImpl Sym = toDRI(EF.getDotSymtabSec(), 0);
+  DataRefImpl Sym = toDRI(DotSymtabSec, 0);
   return basic_symbol_iterator(SymbolRef(Sym, this));
 }
 
 template <class ELFT>
 basic_symbol_iterator ELFObjectFile<ELFT>::symbol_end_impl() const {
-  const Elf_Shdr *SymTab = EF.getDotSymtabSec();
+  const Elf_Shdr *SymTab = DotSymtabSec;
   if (!SymTab)
     return symbol_begin_impl();
   DataRefImpl Sym = toDRI(SymTab, SymTab->sh_size / sizeof(Elf_Sym));