diff --git a/include/llvm/CodeGen/MachineFunction.h b/include/llvm/CodeGen/MachineFunction.h
index b3609c2..09d33b1 100644
--- a/include/llvm/CodeGen/MachineFunction.h
+++ b/include/llvm/CodeGen/MachineFunction.h
@@ -70,7 +70,7 @@
 };
 
 class MachineFunction {
-  Function *Fn;
+  const Function *Fn;
   const TargetMachine &Target;
   MCContext &Ctx;
   MachineModuleInfo &MMI;
@@ -124,8 +124,8 @@
   MachineFunction(const MachineFunction &); // DO NOT IMPLEMENT
   void operator=(const MachineFunction&);   // DO NOT IMPLEMENT
 public:
-  MachineFunction(Function *Fn, const TargetMachine &TM, unsigned FunctionNum,
-                  MachineModuleInfo &MMI);
+  MachineFunction(const Function *Fn, const TargetMachine &TM,
+                  unsigned FunctionNum, MachineModuleInfo &MMI);
   ~MachineFunction();
 
   MachineModuleInfo &getMMI() const { return MMI; }
@@ -133,7 +133,7 @@
   
   /// getFunction - Return the LLVM function that this machine code represents
   ///
-  Function *getFunction() const { return Fn; }
+  const Function *getFunction() const { return Fn; }
 
   /// getFunctionNumber - Return a unique ID for the current function.
   ///
diff --git a/lib/CodeGen/ELFWriter.cpp b/lib/CodeGen/ELFWriter.cpp
index fe55b32..b644ebe 100644
--- a/lib/CodeGen/ELFWriter.cpp
+++ b/lib/CodeGen/ELFWriter.cpp
@@ -208,7 +208,7 @@
 }
 
 // getTextSection - Get the text section for the specified function
-ELFSection &ELFWriter::getTextSection(Function *F) {
+ELFSection &ELFWriter::getTextSection(const Function *F) {
   const MCSectionELF *Text = 
     (const MCSectionELF *)TLOF.SectionForGlobal(F, Mang, TM);
   return getSection(Text->getSectionName(), Text->getType(), Text->getFlags());
diff --git a/lib/CodeGen/ELFWriter.h b/lib/CodeGen/ELFWriter.h
index b61b484..db66ecc 100644
--- a/lib/CodeGen/ELFWriter.h
+++ b/lib/CodeGen/ELFWriter.h
@@ -191,7 +191,7 @@
     ELFSection &getDtorSection();
     ELFSection &getJumpTableSection();
     ELFSection &getConstantPoolSection(MachineConstantPoolEntry &CPE);
-    ELFSection &getTextSection(Function *F);
+    ELFSection &getTextSection(const Function *F);
     ELFSection &getRelocSection(ELFSection &S);
 
     // Helpers for obtaining ELF specific info.
diff --git a/lib/CodeGen/MachineFunction.cpp b/lib/CodeGen/MachineFunction.cpp
index 1a912a3..3cf10b3 100644
--- a/lib/CodeGen/MachineFunction.cpp
+++ b/lib/CodeGen/MachineFunction.cpp
@@ -51,7 +51,7 @@
   MBB->getParent()->DeleteMachineBasicBlock(MBB);
 }
 
-MachineFunction::MachineFunction(Function *F, const TargetMachine &TM,
+MachineFunction::MachineFunction(const Function *F, const TargetMachine &TM,
                                  unsigned FunctionNum, MachineModuleInfo &mmi)
   : Fn(F), Target(TM), Ctx(mmi.getContext()), MMI(mmi) {
   if (TM.getRegisterInfo())
diff --git a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
index 77b5790..7ecaabb 100644
--- a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
+++ b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
@@ -123,10 +123,11 @@
 /// isUsedOutsideOfDefiningBlock - Return true if this instruction is used by
 /// PHI nodes or outside of the basic block that defines it, or used by a
 /// switch or atomic instruction, which may expand to multiple basic blocks.
-static bool isUsedOutsideOfDefiningBlock(Instruction *I) {
+static bool isUsedOutsideOfDefiningBlock(const Instruction *I) {
   if (isa<PHINode>(I)) return true;
-  BasicBlock *BB = I->getParent();
-  for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI != E; ++UI)
+  const BasicBlock *BB = I->getParent();
+  for (Value::const_use_iterator UI = I->use_begin(), E = I->use_end();
+        UI != E; ++UI)
     if (cast<Instruction>(*UI)->getParent() != BB || isa<PHINode>(*UI))
       return true;
   return false;
@@ -135,7 +136,7 @@
 /// isOnlyUsedInEntryBlock - If the specified argument is only used in the
 /// entry block, return true.  This includes arguments used by switches, since
 /// the switch may expand into multiple basic blocks.
-static bool isOnlyUsedInEntryBlock(Argument *A, bool EnableFastISel) {
+static bool isOnlyUsedInEntryBlock(const Argument *A, bool EnableFastISel) {
   // With FastISel active, we may be splitting blocks, so force creation
   // of virtual registers for all non-dead arguments.
   // Don't force virtual registers for byval arguments though, because
@@ -143,8 +144,9 @@
   if (EnableFastISel && !A->hasByValAttr())
     return A->use_empty();
 
-  BasicBlock *Entry = A->getParent()->begin();
-  for (Value::use_iterator UI = A->use_begin(), E = A->use_end(); UI != E; ++UI)
+  const BasicBlock *Entry = A->getParent()->begin();
+  for (Value::const_use_iterator UI = A->use_begin(), E = A->use_end();
+       UI != E; ++UI)
     if (cast<Instruction>(*UI)->getParent() != Entry || isa<SwitchInst>(*UI))
       return false;  // Use not in entry block.
   return true;
@@ -154,7 +156,7 @@
   : TLI(tli) {
 }
 
-void FunctionLoweringInfo::set(Function &fn, MachineFunction &mf,
+void FunctionLoweringInfo::set(const Function &fn, MachineFunction &mf,
                                bool EnableFastISel) {
   Fn = &fn;
   MF = &mf;
@@ -162,7 +164,7 @@
 
   // Create a vreg for each argument register that is not dead and is used
   // outside of the entry block for the function.
-  for (Function::arg_iterator AI = Fn->arg_begin(), E = Fn->arg_end();
+  for (Function::const_arg_iterator AI = Fn->arg_begin(), E = Fn->arg_end();
        AI != E; ++AI)
     if (!isOnlyUsedInEntryBlock(AI, EnableFastISel))
       InitializeRegForValue(AI);
@@ -170,10 +172,10 @@
   // Initialize the mapping of values to registers.  This is only set up for
   // instruction values that are used outside of the block that defines
   // them.
-  Function::iterator BB = Fn->begin(), EB = Fn->end();
-  for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
-    if (AllocaInst *AI = dyn_cast<AllocaInst>(I))
-      if (ConstantInt *CUI = dyn_cast<ConstantInt>(AI->getArraySize())) {
+  Function::const_iterator BB = Fn->begin(), EB = Fn->end();
+  for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E; ++I)
+    if (const AllocaInst *AI = dyn_cast<AllocaInst>(I))
+      if (const ConstantInt *CUI = dyn_cast<ConstantInt>(AI->getArraySize())) {
         const Type *Ty = AI->getAllocatedType();
         uint64_t TySize = TLI.getTargetData()->getTypeAllocSize(Ty);
         unsigned Align =
@@ -187,7 +189,7 @@
       }
 
   for (; BB != EB; ++BB)
-    for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
+    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E; ++I)
       if (!I->use_empty() && isUsedOutsideOfDefiningBlock(I))
         if (!isa<AllocaInst>(I) ||
             !StaticAllocaMap.count(cast<AllocaInst>(I)))
@@ -209,9 +211,9 @@
 
     // Create Machine PHI nodes for LLVM PHI nodes, lowering them as
     // appropriate.
-    PHINode *PN;
+    const PHINode *PN;
     DebugLoc DL;
-    for (BasicBlock::iterator
+    for (BasicBlock::const_iterator
            I = BB->begin(), E = BB->end(); I != E; ++I) {
 
       PN = dyn_cast<PHINode>(I);
@@ -235,7 +237,7 @@
 
   // Mark landing pad blocks.
   for (BB = Fn->begin(); BB != EB; ++BB)
-    if (InvokeInst *Invoke = dyn_cast<InvokeInst>(BB->getTerminator()))
+    if (const InvokeInst *Invoke = dyn_cast<InvokeInst>(BB->getTerminator()))
       MBBMap[Invoke->getSuccessor(1)]->setIsLandingPad();
 }
 
diff --git a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.h b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.h
index 9e972dc..dfbcef9 100644
--- a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.h
+++ b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.h
@@ -48,7 +48,7 @@
 class FunctionLoweringInfo {
 public:
   TargetLowering &TLI;
-  Function *Fn;
+  const Function *Fn;
   MachineFunction *MF;
   MachineRegisterInfo *RegInfo;
 
@@ -93,7 +93,7 @@
   /// set - Initialize this FunctionLoweringInfo with the given Function
   /// and its associated MachineFunction.
   ///
-  void set(Function &Fn, MachineFunction &MF, bool EnableFastISel);
+  void set(const Function &Fn, MachineFunction &MF, bool EnableFastISel);
 
   /// clear - Clear out all the function-specific state. This returns this
   /// FunctionLoweringInfo to an empty state, ready to be used for a
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 8aa4ac3..cdb7f7c 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -3610,7 +3610,7 @@
     if (Val == 0)
       return DAG.getConstantFP(1.0, LHS.getValueType());
 
-    Function *F = DAG.getMachineFunction().getFunction();
+    const Function *F = DAG.getMachineFunction().getFunction();
     if (!F->hasFnAttr(Attribute::OptimizeForSize) ||
         // If optimizing for size, don't insert too many multiplies.  This
         // inserts up to 5 multiplies.
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 7618166..d320b65 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -195,7 +195,7 @@
   assert((!EnableFastISelAbort || EnableFastISel) &&
          "-fast-isel-abort requires -fast-isel");
 
-  Function &Fn = *mf.getFunction();
+  const Function &Fn = *mf.getFunction();
   const TargetInstrInfo &TII = *TM.getInstrInfo();
   const TargetRegisterInfo &TRI = *TM.getRegisterInfo();
 
diff --git a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
index cb762a4..8585c1e 100644
--- a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
+++ b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
@@ -1358,7 +1358,7 @@
     return false;
 
   unsigned Align = (*Op0->memoperands_begin())->getAlignment();
-  Function *Func = MF->getFunction();
+  const Function *Func = MF->getFunction();
   unsigned ReqAlign = STI->hasV6Ops()
     ? TD->getPrefTypeAlignment(Type::getInt64Ty(Func->getContext())) 
     : 8;  // Pre-v6 need 8-byte align