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diff --git a/lib/CodeGen/MachOCodeEmitter.cpp b/lib/CodeGen/MachOCodeEmitter.cpp
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+++ b/lib/CodeGen/MachOCodeEmitter.cpp
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+//===-- MachOEmitter.cpp - Target-independent Mach-O Emitter code --------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "MachOCodeEmitter.h"
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Function.h"
+#include "llvm/CodeGen/MachineConstantPool.h"
+#include "llvm/CodeGen/MachineJumpTableInfo.h"
+#include "llvm/Target/TargetAsmInfo.h"
+#include "llvm/Support/Mangler.h"
+#include "llvm/Support/OutputBuffer.h"
+
+//===----------------------------------------------------------------------===//
+//                       MachOCodeEmitter Implementation
+//===----------------------------------------------------------------------===//
+
+namespace llvm {
+    
+/// startFunction - This callback is invoked when a new machine function is
+/// about to be emitted.
+
+void MachOCodeEmitter::startFunction(MachineFunction &MF) {
+  const TargetData *TD = TM.getTargetData();
+  const Function *F = MF.getFunction();
+
+  // Align the output buffer to the appropriate alignment, power of 2.
+  unsigned FnAlign = F->getAlignment();
+  unsigned TDAlign = TD->getPrefTypeAlignment(F->getType());
+  unsigned Align = Log2_32(std::max(FnAlign, TDAlign));
+  assert(!(Align & (Align-1)) && "Alignment is not a power of two!");
+
+  // Get the Mach-O Section that this function belongs in.
+  MachOSection *MOS = MOW.getTextSection();
+  
+  // FIXME: better memory management
+  MOS->SectionData.reserve(4096);
+  BufferBegin = &MOS->SectionData[0];
+  BufferEnd = BufferBegin + MOS->SectionData.capacity();
+
+  // Upgrade the section alignment if required.
+  if (MOS->align < Align) MOS->align = Align;
+
+  // Round the size up to the correct alignment for starting the new function.
+  if ((MOS->size & ((1 << Align) - 1)) != 0) {
+    MOS->size += (1 << Align);
+    MOS->size &= ~((1 << Align) - 1);
+  }
+
+  // FIXME: Using MOS->size directly here instead of calculating it from the
+  // output buffer size (impossible because the code emitter deals only in raw
+  // bytes) forces us to manually synchronize size and write padding zero bytes
+  // to the output buffer for all non-text sections.  For text sections, we do
+  // not synchonize the output buffer, and we just blow up if anyone tries to
+  // write non-code to it.  An assert should probably be added to
+  // AddSymbolToSection to prevent calling it on the text section.
+  CurBufferPtr = BufferBegin + MOS->size;
+}
+
+/// finishFunction - This callback is invoked after the function is completely
+/// finished.
+
+bool MachOCodeEmitter::finishFunction(MachineFunction &MF) {
+    
+  // Get the Mach-O Section that this function belongs in.
+  MachOSection *MOS = MOW.getTextSection();
+
+  // Get a symbol for the function to add to the symbol table
+  // FIXME: it seems like we should call something like AddSymbolToSection
+  // in startFunction rather than changing the section size and symbol n_value
+  // here.
+  const GlobalValue *FuncV = MF.getFunction();
+  MachOSym FnSym(FuncV, MOW.Mang->getValueName(FuncV), MOS->Index, TAI);
+  FnSym.n_value = MOS->size;
+  MOS->size = CurBufferPtr - BufferBegin;
+  
+  // Emit constant pool to appropriate section(s)
+  emitConstantPool(MF.getConstantPool());
+
+  // Emit jump tables to appropriate section
+  emitJumpTables(MF.getJumpTableInfo());
+  
+  // If we have emitted any relocations to function-specific objects such as 
+  // basic blocks, constant pools entries, or jump tables, record their
+  // addresses now so that we can rewrite them with the correct addresses
+  // later.
+  for (unsigned i = 0, e = Relocations.size(); i != e; ++i) {
+    MachineRelocation &MR = Relocations[i];
+    intptr_t Addr;
+
+    if (MR.isBasicBlock()) {
+      Addr = getMachineBasicBlockAddress(MR.getBasicBlock());
+      MR.setConstantVal(MOS->Index);
+      MR.setResultPointer((void*)Addr);
+    } else if (MR.isJumpTableIndex()) {
+      Addr = getJumpTableEntryAddress(MR.getJumpTableIndex());
+      MR.setConstantVal(MOW.getJumpTableSection()->Index);
+      MR.setResultPointer((void*)Addr);
+    } else if (MR.isConstantPoolIndex()) {
+      Addr = getConstantPoolEntryAddress(MR.getConstantPoolIndex());
+      MR.setConstantVal(CPSections[MR.getConstantPoolIndex()]);
+      MR.setResultPointer((void*)Addr);
+    } else if (MR.isGlobalValue()) {
+      // FIXME: This should be a set or something that uniques
+      MOW.PendingGlobals.push_back(MR.getGlobalValue());
+    } else {
+      assert(0 && "Unhandled relocation type");
+    }
+    MOS->Relocations.push_back(MR);
+  }
+  Relocations.clear();
+  
+  // Finally, add it to the symtab.
+  MOW.SymbolTable.push_back(FnSym);
+
+  // Clear per-function data structures.
+  CPLocations.clear();
+  CPSections.clear();
+  JTLocations.clear();
+  MBBLocations.clear();
+
+  return false;
+}
+
+/// emitConstantPool - For each constant pool entry, figure out which section
+/// the constant should live in, allocate space for it, and emit it to the 
+/// Section data buffer.
+void MachOCodeEmitter::emitConstantPool(MachineConstantPool *MCP) {
+  const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
+  if (CP.empty()) return;
+
+  // FIXME: handle PIC codegen
+  assert(TM.getRelocationModel() != Reloc::PIC_ &&
+         "PIC codegen not yet handled for mach-o jump tables!");
+
+  // Although there is no strict necessity that I am aware of, we will do what
+  // gcc for OS X does and put each constant pool entry in a section of constant
+  // objects of a certain size.  That means that float constants go in the
+  // literal4 section, and double objects go in literal8, etc.
+  //
+  // FIXME: revisit this decision if we ever do the "stick everything into one
+  // "giant object for PIC" optimization.
+  for (unsigned i = 0, e = CP.size(); i != e; ++i) {
+    const Type *Ty = CP[i].getType();
+    unsigned Size = TM.getTargetData()->getTypeAllocSize(Ty);
+
+    MachOSection *Sec = MOW.getConstSection(CP[i].Val.ConstVal);
+    OutputBuffer SecDataOut(Sec->SectionData, is64Bit, isLittleEndian);
+
+    CPLocations.push_back(Sec->SectionData.size());
+    CPSections.push_back(Sec->Index);
+    
+    // FIXME: remove when we have unified size + output buffer
+    Sec->size += Size;
+
+    // Allocate space in the section for the global.
+    // FIXME: need alignment?
+    // FIXME: share between here and AddSymbolToSection?
+    for (unsigned j = 0; j < Size; ++j)
+      SecDataOut.outbyte(0);
+
+    MOW.InitMem(CP[i].Val.ConstVal, &Sec->SectionData[0], CPLocations[i],
+                TM.getTargetData(), Sec->Relocations);
+  }
+}
+
+/// emitJumpTables - Emit all the jump tables for a given jump table info
+/// record to the appropriate section.
+
+void MachOCodeEmitter::emitJumpTables(MachineJumpTableInfo *MJTI) {
+  const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
+  if (JT.empty()) return;
+
+  // FIXME: handle PIC codegen
+  assert(TM.getRelocationModel() != Reloc::PIC_ &&
+         "PIC codegen not yet handled for mach-o jump tables!");
+
+  MachOSection *Sec = MOW.getJumpTableSection();
+  unsigned TextSecIndex = MOW.getTextSection()->Index;
+  OutputBuffer SecDataOut(Sec->SectionData, is64Bit, isLittleEndian);
+
+  for (unsigned i = 0, e = JT.size(); i != e; ++i) {
+    // For each jump table, record its offset from the start of the section,
+    // reserve space for the relocations to the MBBs, and add the relocations.
+    const std::vector<MachineBasicBlock*> &MBBs = JT[i].MBBs;
+    JTLocations.push_back(Sec->SectionData.size());
+    for (unsigned mi = 0, me = MBBs.size(); mi != me; ++mi) {
+      MachineRelocation MR(MOW.GetJTRelocation(Sec->SectionData.size(),
+                                               MBBs[mi]));
+      MR.setResultPointer((void *)JTLocations[i]);
+      MR.setConstantVal(TextSecIndex);
+      Sec->Relocations.push_back(MR);
+      SecDataOut.outaddr(0);
+    }
+  }
+  // FIXME: remove when we have unified size + output buffer
+  Sec->size = Sec->SectionData.size();
+}
+
+} // end namespace llvm
+