use std::vector instead of std::list for both Section and Symbol lists because

we care more about random access than insertion/deletion of elements.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75828 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 194 insertions, 191 deletions

diff --git a/lib/CodeGen/ELF.h b/lib/CodeGen/ELF.h
index 2c37c57..730ba47 100644
--- a/lib/CodeGen/ELF.h
+++ b/lib/CodeGen/ELF.h
@@ -52,6 +52,70 @@ namespace llvm {
     EV_CURRENT = 1
   };
 
+  /// ELFSym - This struct contains information about each symbol that is
+  /// added to logical symbol table for the module.  This is eventually
+  /// turned into a real symbol table in the file.
+  struct ELFSym {
+    // The global value this symbol matches. This should be null if the symbol
+    // is not a global value.
+    const GlobalValue *GV;
+
+    // ELF specific fields
+    unsigned NameIdx;         // Index in .strtab of name, once emitted.
+    uint64_t Value;
+    unsigned Size;
+    uint8_t Info;
+    uint8_t Other;
+    unsigned short SectionIdx;
+
+    // Symbol index into the Symbol table
+    unsigned SymTabIdx;
+
+    enum {
+      STB_LOCAL = 0,
+      STB_GLOBAL = 1,
+      STB_WEAK = 2
+    };
+
+    enum {
+      STT_NOTYPE = 0,
+      STT_OBJECT = 1,
+      STT_FUNC = 2,
+      STT_SECTION = 3,
+      STT_FILE = 4
+    };
+
+    enum {
+      STV_DEFAULT = 0,  // Visibility is specified by binding type
+      STV_INTERNAL = 1, // Defined by processor supplements
+      STV_HIDDEN = 2,   // Not visible to other components
+      STV_PROTECTED = 3 // Visible in other components but not preemptable
+    };
+
+    ELFSym(const GlobalValue *gv) : GV(gv), NameIdx(0), Value(0),
+                                    Size(0), Info(0), Other(STV_DEFAULT),
+                                    SectionIdx(0), SymTabIdx(0) {}
+
+    unsigned getBind() const { return (Info >> 4) & 0xf; }
+    unsigned getType() const { return Info & 0xf; }
+    bool isLocalBind() const { return getBind() == STB_LOCAL; }
+
+    void setBind(unsigned X) {
+      assert(X == (X & 0xF) && "Bind value out of range!");
+      Info = (Info & 0x0F) | (X << 4);
+    }
+
+    void setType(unsigned X) {
+      assert(X == (X & 0xF) && "Type value out of range!");
+      Info = (Info & 0xF0) | X;
+    }
+
+    void setVisibility(unsigned V) {
+      assert(V == (V & 0x3) && "Visibility value out of range!");
+      Other = V;
+    }
+  };
+
   /// ELFSection - This struct contains information about each section that is
   /// emitted to the file.  This is eventually turned into the section header
   /// table at the end of the file.
@@ -117,73 +181,12 @@ namespace llvm {
     /// SectionIdx - The number of the section in the Section Table.
     unsigned short SectionIdx;
 
+    /// Sym - The symbol to represent this section if it has one.
+    ELFSym *Sym;
+
     ELFSection(const std::string &name, bool isLittleEndian, bool is64Bit)
       : BinaryObject(name, isLittleEndian, is64Bit), Type(0), Flags(0), Addr(0),
-        Offset(0), Size(0), Link(0), Info(0), Align(0), EntSize(0) {}
-  };
-
-  /// ELFSym - This struct contains information about each symbol that is
-  /// added to logical symbol table for the module.  This is eventually
-  /// turned into a real symbol table in the file.
-  struct ELFSym {
-    // The global value this symbol matches. This should be null if the symbol
-    // is not a global value.
-    const GlobalValue *GV;
-
-    // ELF specific fields
-    unsigned NameIdx;         // Index in .strtab of name, once emitted.
-    uint64_t Value;
-    unsigned Size;
-    uint8_t Info;
-    uint8_t Other;
-    unsigned short SectionIdx;
-
-    // Symbol index into the Symbol table
-    unsigned SymTabIdx;
-
-    enum {
-      STB_LOCAL = 0,
-      STB_GLOBAL = 1,
-      STB_WEAK = 2 
-    };
-
-    enum {
-      STT_NOTYPE = 0,
-      STT_OBJECT = 1,
-      STT_FUNC = 2,
-      STT_SECTION = 3,
-      STT_FILE = 4
-    };
-
-    enum {
-      STV_DEFAULT = 0,  // Visibility is specified by binding type
-      STV_INTERNAL = 1, // Defined by processor supplements
-      STV_HIDDEN = 2,   // Not visible to other components
-      STV_PROTECTED = 3 // Visible in other components but not preemptable
-    };
-
-    ELFSym(const GlobalValue *gv) : GV(gv), NameIdx(0), Value(0),
-                                    Size(0), Info(0), Other(STV_DEFAULT),
-                                    SectionIdx(ELFSection::SHN_UNDEF),
-                                    SymTabIdx(0) {}
-
-    unsigned getBind() { return (Info >> 4) & 0xf; }
-    unsigned getType() { return Info & 0xf; }
-
-    void setBind(unsigned X) {
-      assert(X == (X & 0xF) && "Bind value out of range!");
-      Info = (Info & 0x0F) | (X << 4);
-    }
-
-    void setType(unsigned X) {
-      assert(X == (X & 0xF) && "Type value out of range!");
-      Info = (Info & 0xF0) | X;
-    }
-
-    void setVisibility(unsigned V) {
-      assert(V == (V & 0x3) && "Type value out of range!");
-      Other = V;
-    }
+        Offset(0), Size(0), Link(0), Info(0), Align(0), EntSize(0), Sym(0) {}
   };
 
   /// ELFRelocation - This class contains all the information necessary to
diff --git a/lib/CodeGen/ELFCodeEmitter.cpp b/lib/CodeGen/ELFCodeEmitter.cpp
index 5133e74..1d15003 100644
--- a/lib/CodeGen/ELFCodeEmitter.cpp
+++ b/lib/CodeGen/ELFCodeEmitter.cpp
@@ -60,23 +60,18 @@ void ELFCodeEmitter::startFunction(MachineFunction &MF) {
 bool ELFCodeEmitter::finishFunction(MachineFunction &MF) {
   // Add a symbol to represent the function.
   const Function *F = MF.getFunction();
-  ELFSym FnSym(F);
-  FnSym.setType(ELFSym::STT_FUNC);
-  FnSym.setBind(EW.getGlobalELFBinding(F));
-  FnSym.setVisibility(EW.getGlobalELFVisibility(F));
-  FnSym.SectionIdx = ES->SectionIdx;
-  FnSym.Size = ES->getCurrentPCOffset()-FnStartOff;
+  ELFSym *FnSym = new ELFSym(F);
+  FnSym->setType(ELFSym::STT_FUNC);
+  FnSym->setBind(EW.getGlobalELFBinding(F));
+  FnSym->setVisibility(EW.getGlobalELFVisibility(F));
+  FnSym->SectionIdx = ES->SectionIdx;
+  FnSym->Size = ES->getCurrentPCOffset()-FnStartOff;
 
   // Offset from start of Section
-  FnSym.Value = FnStartOff;
-
-  // Locals should go on the symbol list front
-  if (!F->hasPrivateLinkage()) {
-    if (FnSym.getBind() == ELFSym::STB_LOCAL)
-      EW.SymbolList.push_front(FnSym);
-    else
-      EW.SymbolList.push_back(FnSym);
-  }
+  FnSym->Value = FnStartOff;
+
+  if (!F->hasPrivateLinkage())
+    EW.SymbolList.push_back(FnSym);
 
   // Emit constant pool to appropriate section(s)
   emitConstantPool(MF.getConstantPool());
diff --git a/lib/CodeGen/ELFWriter.cpp b/lib/CodeGen/ELFWriter.cpp
index 05b7361..a89dae4 100644
--- a/lib/CodeGen/ELFWriter.cpp
+++ b/lib/CodeGen/ELFWriter.cpp
@@ -235,13 +235,13 @@ void ELFWriter::EmitGlobal(const GlobalValue *GV) {
 
   // Handle ELF Bind, Visibility and Type for the current symbol
   unsigned SymBind = getGlobalELFBinding(GV);
-  ELFSym GblSym(GV);
-  GblSym.setBind(SymBind);
-  GblSym.setVisibility(getGlobalELFVisibility(GV));
-  GblSym.setType(getGlobalELFType(GV));
+  ELFSym *GblSym = new ELFSym(GV);
+  GblSym->setBind(SymBind);
+  GblSym->setVisibility(getGlobalELFVisibility(GV));
+  GblSym->setType(getGlobalELFType(GV));
 
   if (isELFUndefSym(GV)) {
-    GblSym.SectionIdx = ELFSection::SHN_UNDEF;
+    GblSym->SectionIdx = ELFSection::SHN_UNDEF;
   } else {
     assert(isa<GlobalVariable>(GV) && "GV not a global variable!");
     const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
@@ -254,41 +254,41 @@ void ELFWriter::EmitGlobal(const GlobalValue *GV) {
     const TargetData *TD = TM.getTargetData();
     unsigned Align = TD->getPreferredAlignment(GVar);
     unsigned Size = TD->getTypeAllocSize(GVar->getInitializer()->getType());
-    GblSym.Size = Size;
+    GblSym->Size = Size;
 
     if (isELFCommonSym(GV)) {
-      GblSym.SectionIdx = ELFSection::SHN_COMMON;
+      GblSym->SectionIdx = ELFSection::SHN_COMMON;
       getSection(S->getName(), ELFSection::SHT_NOBITS, SectionFlags, 1);
 
       // A new linkonce section is created for each global in the
       // common section, the default alignment is 1 and the symbol
       // value contains its alignment.
-      GblSym.Value = Align;
+      GblSym->Value = Align;
 
     } else if (isELFBssSym(GV)) {
       ELFSection &ES =
         getSection(S->getName(), ELFSection::SHT_NOBITS, SectionFlags);
-      GblSym.SectionIdx = ES.SectionIdx;
+      GblSym->SectionIdx = ES.SectionIdx;
 
       // Update the size with alignment and the next object can
       // start in the right offset in the section
       if (Align) ES.Size = (ES.Size + Align-1) & ~(Align-1);
       ES.Align = std::max(ES.Align, Align);
 
-      // GblSym.Value should contain the virtual offset inside the section.
+      // GblSym->Value should contain the virtual offset inside the section.
       // Virtual because the BSS space is not allocated on ELF objects
-      GblSym.Value = ES.Size;
+      GblSym->Value = ES.Size;
       ES.Size += Size;
 
     } else if (isELFDataSym(GV)) {
       ELFSection &ES =
         getSection(S->getName(), ELFSection::SHT_PROGBITS, SectionFlags);
-      GblSym.SectionIdx = ES.SectionIdx;
+      GblSym->SectionIdx = ES.SectionIdx;
 
-      // GblSym.Value should contain the symbol offset inside the section,
+      // GblSym->Value should contain the symbol offset inside the section,
       // and all symbols should start on their required alignment boundary
       ES.Align = std::max(ES.Align, Align);
-      GblSym.Value = (ES.size() + (Align-1)) & (-Align);
+      GblSym->Value = (ES.size() + (Align-1)) & (-Align);
       ES.emitAlignment(ES.Align);
 
       // Emit the global to the data section 'ES'
@@ -296,13 +296,8 @@ void ELFWriter::EmitGlobal(const GlobalValue *GV) {
     }
   }
 
-  // Local symbols should come first on the symbol table.
-  if (!GV->hasPrivateLinkage()) {
-    if (SymBind == ELFSym::STB_LOCAL)
-      SymbolList.push_front(GblSym);
-    else
-      SymbolList.push_back(GblSym);
-  }
+  if (!GV->hasPrivateLinkage())
+    SymbolList.push_back(GblSym);
 }
 
 void ELFWriter::EmitGlobalConstantStruct(const ConstantStruct *CVS,
@@ -419,23 +414,17 @@ bool ELFWriter::doFinalization(Module &M) {
   if (TAI->getNonexecutableStackDirective())
     getNonExecStackSection();
 
-  // Emit a symbol for each section created until now
-  for (std::map<std::string, ELFSection*>::iterator I = SectionLookup.begin(),
-       E = SectionLookup.end(); I != E; ++I) {
-    ELFSection *ES = I->second;
-
-    // Skip null section
-    if (ES->SectionIdx == 0) continue;
-
-    ELFSym SectionSym(0);
-    SectionSym.SectionIdx = ES->SectionIdx;
-    SectionSym.Size = 0;
-    SectionSym.setBind(ELFSym::STB_LOCAL);
-    SectionSym.setType(ELFSym::STT_SECTION);
-    SectionSym.setVisibility(ELFSym::STV_DEFAULT);
-
-    // Local symbols go in the list front
-    SymbolList.push_front(SectionSym);
+  // Emit a symbol for each section created until now, skip null section
+  for (unsigned i = 1, e = SectionList.size(); i < e; ++i) {
+    ELFSection &ES = *SectionList[i];
+    ELFSym *SectionSym = new ELFSym(0);
+    SectionSym->SectionIdx = ES.SectionIdx;
+    SectionSym->Size = 0;
+    SectionSym->setBind(ELFSym::STB_LOCAL);
+    SectionSym->setType(ELFSym::STT_SECTION);
+    SectionSym->setVisibility(ELFSym::STV_DEFAULT);
+    SymbolList.push_back(SectionSym);
+    ES.Sym = SymbolList.back();
   }
 
   // Emit string table
@@ -454,6 +443,7 @@ bool ELFWriter::doFinalization(Module &M) {
   OutputSectionsAndSectionTable();
 
   // We are done with the abstract symbols.
+  SymbolList.clear();
   SectionList.clear();
   NumSections = 0;
 
@@ -466,26 +456,26 @@ bool ELFWriter::doFinalization(Module &M) {
 void ELFWriter::EmitRelocations() {
 
   // Create Relocation sections for each section which needs it.
-  for (std::list<ELFSection>::iterator I = SectionList.begin(),
-       E = SectionList.end(); I != E; ++I) {
+  for (unsigned i=0, e=SectionList.size(); i < e; ++i) {
+    ELFSection &S = *SectionList[i];
 
     // This section does not have relocations
-    if (!I->hasRelocations()) continue;
+    if (!S.hasRelocations()) continue;
 
-    // Get the relocation section for section 'I'
+    // Get the relocation section for section 'S'
     bool HasRelA = TEW->hasRelocationAddend();
-    ELFSection &RelSec = getRelocSection(I->getName(), HasRelA,
+    ELFSection &RelSec = getRelocSection(S.getName(), HasRelA,
                                          TEW->getPrefELFAlignment());
 
     // 'Link' - Section hdr idx of the associated symbol table
     // 'Info' - Section hdr idx of the section to which the relocation applies
     ELFSection &SymTab = getSymbolTableSection();
     RelSec.Link = SymTab.SectionIdx;
-    RelSec.Info = I->SectionIdx;
+    RelSec.Info = S.SectionIdx;
     RelSec.EntSize = TEW->getRelocationEntrySize();
 
     // Get the relocations from Section
-    std::vector<MachineRelocation> Relos = I->getRelocations();
+    std::vector<MachineRelocation> Relos = S.getRelocations();
     for (std::vector<MachineRelocation>::iterator MRI = Relos.begin(),
          MRE = Relos.end(); MRI != MRE; ++MRI) {
       MachineRelocation &MR = *MRI;
@@ -510,15 +500,10 @@ void ELFWriter::EmitRelocations() {
         SymIdx = GblSymLookup[G];
         Addend = TEW->getAddendForRelTy(RelType);
       } else {
+        // Get the symbol index for the section symbol referenced
+        // by the relocation
         unsigned SectionIdx = MR.getConstantVal();
-        // TODO: use a map for this.
-        for (std::list<ELFSym>::iterator I = SymbolList.begin(),
-             E = SymbolList.end(); I != E; ++I)
-          if ((SectionIdx == I->SectionIdx) &&
-              (I->getType() == ELFSym::STT_SECTION)) {
-            SymIdx = I->SymTabIdx;
-            break;
-          }
+        SymIdx = SectionList[SectionIdx]->Sym->SymTabIdx;
         Addend = (uint64_t)MR.getResultPointer();
       }
 
@@ -596,17 +581,17 @@ void ELFWriter::EmitStringTable() {
   // Walk on the symbol list and write symbol names into the
   // string table.
   unsigned Index = 1;
-  for (std::list<ELFSym>::iterator I = SymbolList.begin(),
-       E = SymbolList.end(); I != E; ++I) {
+  for (unsigned i = 0, e = SymbolList.size(); i < e; ++i) {
+    ELFSym &Sym = *SymbolList[i];
 
     // Use the name mangler to uniquify the LLVM symbol.
     std::string Name;
-    if (I->GV) Name.append(Mang->getMangledName(I->GV));
+    if (Sym.GV) Name.append(Mang->getMangledName(Sym.GV));
 
     if (Name.empty()) {
-      I->NameIdx = 0;
+      Sym.NameIdx = 0;
     } else {
-      I->NameIdx = Index;
+      Sym.NameIdx = Index;
       StrTab.emitString(Name);
 
       // Keep track of the number of bytes emitted to this section.
@@ -617,11 +602,38 @@ void ELFWriter::EmitStringTable() {
   StrTab.Size = Index;
 }
 
+// SortSymbols - On the symbol table local symbols must come before
+// all other symbols with non-local bindings. The return value is
+// the position of the first non local symbol.
+unsigned ELFWriter::SortSymbols() {
+  unsigned FirstNonLocalSymbol, i, e;
+  std::vector<ELFSym*> LocalSyms, OtherSyms;
+
+  for (i = 0, e = SymbolList.size(); i < e; ++i) {
+    if (SymbolList[i]->isLocalBind())
+      LocalSyms.push_back(SymbolList[i]);
+    else
+      OtherSyms.push_back(SymbolList[i]);
+  }
+  SymbolList.clear();
+  FirstNonLocalSymbol = LocalSyms.size();
+
+  for (i = 0; i < FirstNonLocalSymbol; ++i)
+    SymbolList.push_back(LocalSyms[i]);
+
+  for (i = 0, e = OtherSyms.size(); i < e; ++i)
+    SymbolList.push_back(OtherSyms[i]);
+
+  LocalSyms.clear();
+  OtherSyms.clear();
+
+  return FirstNonLocalSymbol;
+}
+
 /// EmitSymbolTable - Emit the symbol table itself.
 void ELFWriter::EmitSymbolTable() {
   if (!SymbolList.size()) return;  // Empty symbol table.
 
-  unsigned FirstNonLocalSymbol = 1;
   // Now that we have emitted the string table and know the offset into the
   // string table of each symbol, emit the symbol table itself.
   ELFSection &SymTab = getSymbolTableSection();
@@ -634,29 +646,26 @@ void ELFWriter::EmitSymbolTable() {
   SymTab.EntSize = TEW->getSymTabEntrySize();
 
   // The first entry in the symtab is the null symbol
-  ELFSym NullSym = ELFSym(0);
-  EmitSymbol(SymTab, NullSym);
+  SymbolList.insert(SymbolList.begin(), new ELFSym(0));
 
-  // Emit all the symbols to the symbol table. Skip the null
-  // symbol, cause it's emitted already
-  unsigned Index = 1;
-  for (std::list<ELFSym>::iterator I = SymbolList.begin(),
-       E = SymbolList.end(); I != E; ++I, ++Index) {
-    // Keep track of the first non-local symbol
-    if (I->getBind() == ELFSym::STB_LOCAL)
-      FirstNonLocalSymbol++;
+  // Reorder the symbol table with local symbols first!
+  unsigned FirstNonLocalSymbol = SortSymbols();
+
+  // Emit all the symbols to the symbol table.
+  for (unsigned i = 0, e = SymbolList.size(); i < e; ++i) {
+    ELFSym &Sym = *SymbolList[i];
 
     // Emit symbol to the symbol table
-    EmitSymbol(SymTab, *I);
+    EmitSymbol(SymTab, Sym);
 
     // Record the symbol table index for each global value
-    if (I->GV)
-      GblSymLookup[I->GV] = Index;
+    if (Sym.GV) GblSymLookup[Sym.GV] = i;
 
     // Keep track on the symbol index into the symbol table
-    I->SymTabIdx = Index;
+    Sym.SymTabIdx = i;
   }
 
+  // One greater than the symbol table index of the last local symbol
   SymTab.Info = FirstNonLocalSymbol;
   SymTab.Size = SymTab.size();
 }
@@ -676,15 +685,14 @@ void ELFWriter::EmitSectionTableStringTable() {
   // the string table.
   unsigned Index = 0;
 
-  for (std::list<ELFSection>::iterator I = SectionList.begin(),
-         E = SectionList.end(); I != E; ++I) {
+  for (unsigned i=0, e=SectionList.size(); i < e; ++i) {
     // Set the index into the table.  Note if we have lots of entries with
     // common suffixes, we could memoize them here if we cared.
-    I->NameIdx = Index;
-    SHStrTab.emitString(I->getName());
+    SectionList[i]->NameIdx = Index;
+    SHStrTab.emitString(SectionList[i]->getName());
 
     // Keep track of the number of bytes emitted to this section.
-    Index += I->getName().size()+1;
+    Index += SectionList[i]->getName().size()+1;
   }
 
   // Set the size of .shstrtab now that we know what it is.
@@ -699,29 +707,24 @@ void ELFWriter::OutputSectionsAndSectionTable() {
   // Pass #1: Compute the file offset for each section.
   size_t FileOff = ElfHdr.size();   // File header first.
 
-  // Adjust alignment of all section if needed.
-  for (std::list<ELFSection>::iterator I = SectionList.begin(),
-         E = SectionList.end(); I != E; ++I) {
-
-    // Section idx 0 has 0 offset
-    if (!I->SectionIdx)
-      continue;
-
-    if (!I->size()) {
-      I->Offset = FileOff;
+  // Adjust alignment of all section if needed, skip the null section.
+  for (unsigned i=1, e=SectionList.size(); i < e; ++i) {
+    ELFSection &ES = *SectionList[i];
+    if (!ES.size()) {
+      ES.Offset = FileOff;
       continue;
     }
 
     // Update Section size
-    if (!I->Size)
-      I->Size = I->size();
+    if (!ES.Size)
+      ES.Size = ES.size();
 
     // Align FileOff to whatever the alignment restrictions of the section are.
-    if (I->Align)
-      FileOff = (FileOff+I->Align-1) & ~(I->Align-1);
+    if (ES.Align)
+      FileOff = (FileOff+ES.Align-1) & ~(ES.Align-1);
 
-    I->Offset = FileOff;
-    FileOff += I->Size;
+    ES.Offset = FileOff;
+    FileOff += ES.Size;
   }
 
   // Align Section Header.
@@ -745,8 +748,8 @@ void ELFWriter::OutputSectionsAndSectionTable() {
   BinaryObject SHdrTable(isLittleEndian, is64Bit);
 
   // Emit all of sections to the file and build the section header table.
-  while (!SectionList.empty()) {
-    ELFSection &S = *SectionList.begin();
+  for (unsigned i=0, e=SectionList.size(); i < e; ++i) {
+    ELFSection &S = *SectionList[i];
     DOUT << "SectionIdx: " << S.SectionIdx << ", Name: " << S.getName()
          << ", Size: " << S.Size << ", Offset: " << S.Offset
          << ", SectionData Size: " << S.size() << "\n";
@@ -763,7 +766,6 @@ void ELFWriter::OutputSectionsAndSectionTable() {
     }
 
     EmitSectionHeader(SHdrTable, S);
-    SectionList.pop_front();
   }
 
   // Align output for the section table.
diff --git a/lib/CodeGen/ELFWriter.h b/lib/CodeGen/ELFWriter.h
index b0d7f3b..3cc50fe 100644
--- a/lib/CodeGen/ELFWriter.h
+++ b/lib/CodeGen/ELFWriter.h
@@ -16,7 +16,6 @@
 
 #include "llvm/ADT/SetVector.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
-#include <list>
 #include <map>
 
 namespace llvm {
@@ -95,13 +94,13 @@ namespace llvm {
     BinaryObject ElfHdr;
 
     /// SectionList - This is the list of sections that we have emitted to the
-    /// file.  Once the file has been completely built, the section header table
+    /// file. Once the file has been completely built, the section header table
     /// is constructed from this info.
-    std::list<ELFSection> SectionList;
+    std::vector<ELFSection*> SectionList;
     unsigned NumSections;   // Always = SectionList.size()
 
     /// SectionLookup - This is a mapping from section name to section number in
-    /// the SectionList.
+    /// the SectionList. Used to quickly gather the Section Index from TAI names
     std::map<std::string, ELFSection*> SectionLookup;
 
     /// GblSymLookup - This is a mapping from global value to a symbol index
@@ -109,17 +108,18 @@ namespace llvm {
     /// must be quickly mapped to a symbol table index
     std::map<const GlobalValue*, uint32_t> GblSymLookup;
 
-    /// SymbolList - This is the list of symbols emitted to the symbol table
-    /// Local symbols go to the front and Globals to the back.
-    std::list<ELFSym> SymbolList;
+    /// SymbolList - This is the list of symbols emitted to the symbol table.
+    /// When the SymbolList is finally built, local symbols must be placed in
+    /// the beginning while non-locals at the end.
+    std::vector<ELFSym*> SymbolList;
 
     /// PendingGlobals - List of externally defined symbols that we have been
     /// asked to emit, but have not seen a reference to.  When a reference
     /// is seen, the symbol will move from this list to the SymbolList.
     SetVector<GlobalValue*> PendingGlobals;
 
-    // Remove tab from section name prefix. This is necessary becase TAI 
-    // sometimes return a section name prefixed with a "\t" char. This is
+    // Remove tab from section name prefix. This is necessary becase TAI
+    // sometimes return a section name prefixed with elf unused chars. This is
     // a little bit dirty. FIXME: find a better approach, maybe add more
     // methods to TAI to get the clean name?
     void fixNameForSection(std::string &Name) {
@@ -140,14 +140,14 @@ namespace llvm {
     /// section if one does not already exist.
     ELFSection &getSection(const std::string &Name, unsigned Type,
                            unsigned Flags = 0, unsigned Align = 0) {
-      std::string SectionName(Name);
-      fixNameForSection(SectionName);
+      std::string SName(Name);
+      fixNameForSection(SName);
 
-      ELFSection *&SN = SectionLookup[SectionName];
+      ELFSection *&SN = SectionLookup[SName];
       if (SN) return *SN;
 
-      SectionList.push_back(ELFSection(SectionName, isLittleEndian, is64Bit));
-      SN = &SectionList.back();
+      SectionList.push_back(new ELFSection(SName, isLittleEndian, is64Bit));
+      SN = SectionList.back();
       SN->SectionIdx = NumSections++;
       SN->Type = Type;
       SN->Flags = Flags;
@@ -245,6 +245,7 @@ namespace llvm {
     void EmitSymbolTable();
     void EmitStringTable();
     void OutputSectionsAndSectionTable();
+    unsigned SortSymbols();
   };
 }
 
diff --git a/lib/Target/X86/X86ELFWriterInfo.cpp b/lib/Target/X86/X86ELFWriterInfo.cpp
index a26fe8c..2736a81 100644
--- a/lib/Target/X86/X86ELFWriterInfo.cpp
+++ b/lib/Target/X86/X86ELFWriterInfo.cpp
@@ -65,6 +65,8 @@ long int X86ELFWriterInfo::getAddendForRelTy(unsigned RelTy) const {
     switch(RelTy) {
     case R_X86_64_PC32: return -4;
       break;
+    case R_X86_64_32: return 0;
+      break;
     default:
       llvm_unreachable("unknown x86 relocation type");
     }