From 4cda58168a97778ebd1cf57d3bc66804b45c1966 Mon Sep 17 00:00:00 2001
From: Rafael Espindola <rafael.espindola@gmail.com>
Date: Fri, 16 Oct 2015 15:29:48 +0000
Subject: [PATCH] Add a ObjectFile<ELFT>::getSection helper and simplify. NFC.

llvm-svn: 250519
---
 lld/ELF/InputFiles.cpp     | 27 +++++++++++++++++----------
 lld/ELF/InputFiles.h       |  1 +
 lld/ELF/OutputSections.cpp | 29 +++++------------------------
 3 files changed, 23 insertions(+), 34 deletions(-)

diff --git a/lld/ELF/InputFiles.cpp b/lld/ELF/InputFiles.cpp
index b154ac63c2ad..661ea64c1768 100644
--- a/lld/ELF/InputFiles.cpp
+++ b/lld/ELF/InputFiles.cpp
@@ -172,6 +172,21 @@ template <class ELFT> void elf2::ObjectFile<ELFT>::initializeSymbols() {
     this->SymbolBodies.push_back(createSymbolBody(this->StringTable, &Sym));
 }
 
+template <class ELFT>
+InputSection<ELFT> *
+elf2::ObjectFile<ELFT>::getSection(const Elf_Sym &Sym) const {
+  uint32_t Index = Sym.st_shndx;
+  if (Index == ELF::SHN_XINDEX)
+    Index = this->ELFObj.getExtendedSymbolTableIndex(&Sym, this->Symtab,
+                                                     SymtabSHNDX);
+  else if (Index == ELF::SHN_UNDEF || Index >= ELF::SHN_LORESERVE)
+    return nullptr;
+
+  if (Index >= Sections.size() || !Index || !Sections[Index])
+    error("Invalid section index");
+  return Sections[Index];
+}
+
 template <class ELFT>
 SymbolBody *elf2::ObjectFile<ELFT>::createSymbolBody(StringRef StringTable,
                                                      const Elf_Sym *Sym) {
@@ -179,30 +194,22 @@ SymbolBody *elf2::ObjectFile<ELFT>::createSymbolBody(StringRef StringTable,
   error(NameOrErr.getError());
   StringRef Name = *NameOrErr;
 
-  uint32_t SecIndex = Sym->st_shndx;
-  switch (SecIndex) {
+  switch (Sym->st_shndx) {
   case SHN_ABS:
     return new (this->Alloc) DefinedAbsolute<ELFT>(Name, *Sym);
   case SHN_UNDEF:
     return new (this->Alloc) Undefined<ELFT>(Name, *Sym);
   case SHN_COMMON:
     return new (this->Alloc) DefinedCommon<ELFT>(Name, *Sym);
-  case SHN_XINDEX:
-    SecIndex = this->ELFObj.getExtendedSymbolTableIndex(Sym, this->Symtab,
-                                                        SymtabSHNDX);
-    break;
   }
 
-  if (SecIndex >= Sections.size() || !SecIndex || !Sections[SecIndex])
-    error("Invalid section index");
-
   switch (Sym->getBinding()) {
   default:
     error("unexpected binding");
   case STB_GLOBAL:
   case STB_WEAK:
   case STB_GNU_UNIQUE: {
-    InputSection<ELFT> *Sec = Sections[SecIndex];
+    InputSection<ELFT> *Sec = getSection(*Sym);
     if (Sec == &InputSection<ELFT>::Discarded)
       return new (this->Alloc) Undefined<ELFT>(Name, *Sym);
     return new (this->Alloc) DefinedRegular<ELFT>(Name, *Sym, *Sec);
diff --git a/lld/ELF/InputFiles.h b/lld/ELF/InputFiles.h
index 00ab848eddf5..00b44201d9d5 100644
--- a/lld/ELF/InputFiles.h
+++ b/lld/ELF/InputFiles.h
@@ -111,6 +111,7 @@ public:
   void parse(llvm::DenseSet<StringRef> &Comdats);
 
   ArrayRef<InputSection<ELFT> *> getSections() const { return Sections; }
+  InputSection<ELFT> *getSection(const Elf_Sym &Sym) const;
 
   SymbolBody *getSymbolBody(uint32_t SymbolIndex) const {
     uint32_t FirstNonLocal = this->Symtab->sh_info;
diff --git a/lld/ELF/OutputSections.cpp b/lld/ELF/OutputSections.cpp
index 6d27e421d1a2..7f7b970a72f8 100644
--- a/lld/ELF/OutputSections.cpp
+++ b/lld/ELF/OutputSections.cpp
@@ -434,17 +434,11 @@ lld::elf2::getLocalRelTarget(const ObjectFile<ELFT> &File,
   if (!Sym)
     return 0;
 
-  uint32_t SecIndex = Sym->st_shndx;
-  if (SecIndex == SHN_XINDEX)
-    SecIndex = File.getObj().getExtendedSymbolTableIndex(
-        Sym, File.getSymbolTable(), File.getSymbolTableShndx());
-  ArrayRef<InputSection<ELFT> *> Sections = File.getSections();
-  InputSection<ELFT> *Section = Sections[SecIndex];
-
   // According to the ELF spec reference to a local symbol from outside
   // the group are not allowed. Unfortunately .eh_frame breaks that rule
   // and must be treated specially. For now we just replace the symbol with
   // 0.
+  InputSection<ELFT> *Section = File.getSection(*Sym);
   if (Section == &InputSection<ELFT>::Discarded)
     return 0;
 
@@ -535,16 +529,8 @@ bool lld::elf2::shouldKeepInSymtab(const ObjectFile<ELFT> &File,
     return false;
 
   // If sym references a section in a discarded group, don't keep it.
-  uint32_t SecIndex = Sym.st_shndx;
-  if (SecIndex != SHN_ABS) {
-    if (SecIndex == SHN_XINDEX)
-      SecIndex = File.getObj().getExtendedSymbolTableIndex(
-          &Sym, File.getSymbolTable(), File.getSymbolTableShndx());
-    ArrayRef<InputSection<ELFT> *> Sections = File.getSections();
-    const InputSection<ELFT> *Section = Sections[SecIndex];
-    if (Section == &InputSection<ELFT>::Discarded)
-      return false;
-  }
+  if (File.getSection(Sym) == &InputSection<ELFT>::Discarded)
+    return false;
 
   if (Config->DiscardNone)
     return true;
@@ -611,16 +597,11 @@ void SymbolTableSection<ELFT>::writeLocalSymbols(uint8_t *&Buf) {
       ESym->st_name = StrTabSec.getFileOff(SymName);
       ESym->st_size = Sym.st_size;
       ESym->setBindingAndType(Sym.getBinding(), Sym.getType());
-      uint32_t SecIndex = Sym.st_shndx;
       uintX_t VA = Sym.st_value;
-      if (SecIndex == SHN_ABS) {
+      if (Sym.st_shndx == SHN_ABS) {
         ESym->st_shndx = SHN_ABS;
       } else {
-        if (SecIndex == SHN_XINDEX)
-          SecIndex = File->getObj().getExtendedSymbolTableIndex(
-              &Sym, File->getSymbolTable(), File->getSymbolTableShndx());
-        ArrayRef<InputSection<ELFT> *> Sections = File->getSections();
-        const InputSection<ELFT> *Sec = Sections[SecIndex];
+        const InputSection<ELFT> *Sec = File->getSection(Sym);
         ESym->st_shndx = Sec->OutSec->SectionIndex;
         VA += Sec->OutSec->getVA() + Sec->OutSecOff;
       }