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diff --git a/contrib/llvm/lib/Analysis/AliasAnalysis.cpp b/contrib/llvm/lib/Analysis/AliasAnalysis.cpp
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+++ b/contrib/llvm/lib/Analysis/AliasAnalysis.cpp
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+//===- AliasAnalysis.cpp - Generic Alias Analysis Interface Implementation -==//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the generic AliasAnalysis interface which is used as the
+// common interface used by all clients and implementations of alias analysis.
+//
+// This file also implements the default version of the AliasAnalysis interface
+// that is to be used when no other implementation is specified.  This does some
+// simple tests that detect obvious cases: two different global pointers cannot
+// alias, a global cannot alias a malloc, two different mallocs cannot alias,
+// etc.
+//
+// This alias analysis implementation really isn't very good for anything, but
+// it is very fast, and makes a nice clean default implementation.  Because it
+// handles lots of little corner cases, other, more complex, alias analysis
+// implementations may choose to rely on this pass to resolve these simple and
+// easy cases.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/CaptureTracking.h"
+#include "llvm/Analysis/Dominators.h"
+#include "llvm/Analysis/ValueTracking.h"
+#include "llvm/IR/BasicBlock.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Type.h"
+#include "llvm/Pass.h"
+#include "llvm/Target/TargetLibraryInfo.h"
+using namespace llvm;
+
+// Register the AliasAnalysis interface, providing a nice name to refer to.
+INITIALIZE_ANALYSIS_GROUP(AliasAnalysis, "Alias Analysis", NoAA)
+char AliasAnalysis::ID = 0;
+
+//===----------------------------------------------------------------------===//
+// Default chaining methods
+//===----------------------------------------------------------------------===//
+
+AliasAnalysis::AliasResult
+AliasAnalysis::alias(const Location &LocA, const Location &LocB) {
+  assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!");
+  return AA->alias(LocA, LocB);
+}
+
+bool AliasAnalysis::pointsToConstantMemory(const Location &Loc,
+                                           bool OrLocal) {
+  assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!");
+  return AA->pointsToConstantMemory(Loc, OrLocal);
+}
+
+void AliasAnalysis::deleteValue(Value *V) {
+  assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!");
+  AA->deleteValue(V);
+}
+
+void AliasAnalysis::copyValue(Value *From, Value *To) {
+  assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!");
+  AA->copyValue(From, To);
+}
+
+void AliasAnalysis::addEscapingUse(Use &U) {
+  assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!");
+  AA->addEscapingUse(U);
+}
+
+
+AliasAnalysis::ModRefResult
+AliasAnalysis::getModRefInfo(ImmutableCallSite CS,
+                             const Location &Loc) {
+  assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!");
+
+  ModRefBehavior MRB = getModRefBehavior(CS);
+  if (MRB == DoesNotAccessMemory)
+    return NoModRef;
+
+  ModRefResult Mask = ModRef;
+  if (onlyReadsMemory(MRB))
+    Mask = Ref;
+
+  if (onlyAccessesArgPointees(MRB)) {
+    bool doesAlias = false;
+    if (doesAccessArgPointees(MRB)) {
+      MDNode *CSTag = CS.getInstruction()->getMetadata(LLVMContext::MD_tbaa);
+      for (ImmutableCallSite::arg_iterator AI = CS.arg_begin(), AE = CS.arg_end();
+           AI != AE; ++AI) {
+        const Value *Arg = *AI;
+        if (!Arg->getType()->isPointerTy())
+          continue;
+        Location CSLoc(Arg, UnknownSize, CSTag);
+        if (!isNoAlias(CSLoc, Loc)) {
+          doesAlias = true;
+          break;
+        }
+      }
+    }
+    if (!doesAlias)
+      return NoModRef;
+  }
+
+  // If Loc is a constant memory location, the call definitely could not
+  // modify the memory location.
+  if ((Mask & Mod) && pointsToConstantMemory(Loc))
+    Mask = ModRefResult(Mask & ~Mod);
+
+  // If this is the end of the chain, don't forward.
+  if (!AA) return Mask;
+
+  // Otherwise, fall back to the next AA in the chain. But we can merge
+  // in any mask we've managed to compute.
+  return ModRefResult(AA->getModRefInfo(CS, Loc) & Mask);
+}
+
+AliasAnalysis::ModRefResult
+AliasAnalysis::getModRefInfo(ImmutableCallSite CS1, ImmutableCallSite CS2) {
+  assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!");
+
+  // If CS1 or CS2 are readnone, they don't interact.
+  ModRefBehavior CS1B = getModRefBehavior(CS1);
+  if (CS1B == DoesNotAccessMemory) return NoModRef;
+
+  ModRefBehavior CS2B = getModRefBehavior(CS2);
+  if (CS2B == DoesNotAccessMemory) return NoModRef;
+
+  // If they both only read from memory, there is no dependence.
+  if (onlyReadsMemory(CS1B) && onlyReadsMemory(CS2B))
+    return NoModRef;
+
+  AliasAnalysis::ModRefResult Mask = ModRef;
+
+  // If CS1 only reads memory, the only dependence on CS2 can be
+  // from CS1 reading memory written by CS2.
+  if (onlyReadsMemory(CS1B))
+    Mask = ModRefResult(Mask & Ref);
+
+  // If CS2 only access memory through arguments, accumulate the mod/ref
+  // information from CS1's references to the memory referenced by
+  // CS2's arguments.
+  if (onlyAccessesArgPointees(CS2B)) {
+    AliasAnalysis::ModRefResult R = NoModRef;
+    if (doesAccessArgPointees(CS2B)) {
+      MDNode *CS2Tag = CS2.getInstruction()->getMetadata(LLVMContext::MD_tbaa);
+      for (ImmutableCallSite::arg_iterator
+           I = CS2.arg_begin(), E = CS2.arg_end(); I != E; ++I) {
+        const Value *Arg = *I;
+        if (!Arg->getType()->isPointerTy())
+          continue;
+        Location CS2Loc(Arg, UnknownSize, CS2Tag);
+        R = ModRefResult((R | getModRefInfo(CS1, CS2Loc)) & Mask);
+        if (R == Mask)
+          break;
+      }
+    }
+    return R;
+  }
+
+  // If CS1 only accesses memory through arguments, check if CS2 references
+  // any of the memory referenced by CS1's arguments. If not, return NoModRef.
+  if (onlyAccessesArgPointees(CS1B)) {
+    AliasAnalysis::ModRefResult R = NoModRef;
+    if (doesAccessArgPointees(CS1B)) {
+      MDNode *CS1Tag = CS1.getInstruction()->getMetadata(LLVMContext::MD_tbaa);
+      for (ImmutableCallSite::arg_iterator
+           I = CS1.arg_begin(), E = CS1.arg_end(); I != E; ++I) {
+        const Value *Arg = *I;
+        if (!Arg->getType()->isPointerTy())
+          continue;
+        Location CS1Loc(Arg, UnknownSize, CS1Tag);
+        if (getModRefInfo(CS2, CS1Loc) != NoModRef) {
+          R = Mask;
+          break;
+        }
+      }
+    }
+    if (R == NoModRef)
+      return R;
+  }
+
+  // If this is the end of the chain, don't forward.
+  if (!AA) return Mask;
+
+  // Otherwise, fall back to the next AA in the chain. But we can merge
+  // in any mask we've managed to compute.
+  return ModRefResult(AA->getModRefInfo(CS1, CS2) & Mask);
+}
+
+AliasAnalysis::ModRefBehavior
+AliasAnalysis::getModRefBehavior(ImmutableCallSite CS) {
+  assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!");
+
+  ModRefBehavior Min = UnknownModRefBehavior;
+
+  // Call back into the alias analysis with the other form of getModRefBehavior
+  // to see if it can give a better response.
+  if (const Function *F = CS.getCalledFunction())
+    Min = getModRefBehavior(F);
+
+  // If this is the end of the chain, don't forward.
+  if (!AA) return Min;
+
+  // Otherwise, fall back to the next AA in the chain. But we can merge
+  // in any result we've managed to compute.
+  return ModRefBehavior(AA->getModRefBehavior(CS) & Min);
+}
+
+AliasAnalysis::ModRefBehavior
+AliasAnalysis::getModRefBehavior(const Function *F) {
+  assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!");
+  return AA->getModRefBehavior(F);
+}
+
+//===----------------------------------------------------------------------===//
+// AliasAnalysis non-virtual helper method implementation
+//===----------------------------------------------------------------------===//
+
+AliasAnalysis::Location AliasAnalysis::getLocation(const LoadInst *LI) {
+  return Location(LI->getPointerOperand(),
+                  getTypeStoreSize(LI->getType()),
+                  LI->getMetadata(LLVMContext::MD_tbaa));
+}
+
+AliasAnalysis::Location AliasAnalysis::getLocation(const StoreInst *SI) {
+  return Location(SI->getPointerOperand(),
+                  getTypeStoreSize(SI->getValueOperand()->getType()),
+                  SI->getMetadata(LLVMContext::MD_tbaa));
+}
+
+AliasAnalysis::Location AliasAnalysis::getLocation(const VAArgInst *VI) {
+  return Location(VI->getPointerOperand(),
+                  UnknownSize,
+                  VI->getMetadata(LLVMContext::MD_tbaa));
+}
+
+AliasAnalysis::Location
+AliasAnalysis::getLocation(const AtomicCmpXchgInst *CXI) {
+  return Location(CXI->getPointerOperand(),
+                  getTypeStoreSize(CXI->getCompareOperand()->getType()),
+                  CXI->getMetadata(LLVMContext::MD_tbaa));
+}
+
+AliasAnalysis::Location
+AliasAnalysis::getLocation(const AtomicRMWInst *RMWI) {
+  return Location(RMWI->getPointerOperand(),
+                  getTypeStoreSize(RMWI->getValOperand()->getType()),
+                  RMWI->getMetadata(LLVMContext::MD_tbaa));
+}
+
+AliasAnalysis::Location 
+AliasAnalysis::getLocationForSource(const MemTransferInst *MTI) {
+  uint64_t Size = UnknownSize;
+  if (ConstantInt *C = dyn_cast<ConstantInt>(MTI->getLength()))
+    Size = C->getValue().getZExtValue();
+
+  // memcpy/memmove can have TBAA tags. For memcpy, they apply
+  // to both the source and the destination.
+  MDNode *TBAATag = MTI->getMetadata(LLVMContext::MD_tbaa);
+
+  return Location(MTI->getRawSource(), Size, TBAATag);
+}
+
+AliasAnalysis::Location 
+AliasAnalysis::getLocationForDest(const MemIntrinsic *MTI) {
+  uint64_t Size = UnknownSize;
+  if (ConstantInt *C = dyn_cast<ConstantInt>(MTI->getLength()))
+    Size = C->getValue().getZExtValue();
+
+  // memcpy/memmove can have TBAA tags. For memcpy, they apply
+  // to both the source and the destination.
+  MDNode *TBAATag = MTI->getMetadata(LLVMContext::MD_tbaa);
+  
+  return Location(MTI->getRawDest(), Size, TBAATag);
+}
+
+
+
+AliasAnalysis::ModRefResult
+AliasAnalysis::getModRefInfo(const LoadInst *L, const Location &Loc) {
+  // Be conservative in the face of volatile/atomic.
+  if (!L->isUnordered())
+    return ModRef;
+
+  // If the load address doesn't alias the given address, it doesn't read
+  // or write the specified memory.
+  if (!alias(getLocation(L), Loc))
+    return NoModRef;
+
+  // Otherwise, a load just reads.
+  return Ref;
+}
+
+AliasAnalysis::ModRefResult
+AliasAnalysis::getModRefInfo(const StoreInst *S, const Location &Loc) {
+  // Be conservative in the face of volatile/atomic.
+  if (!S->isUnordered())
+    return ModRef;
+
+  // If the store address cannot alias the pointer in question, then the
+  // specified memory cannot be modified by the store.
+  if (!alias(getLocation(S), Loc))
+    return NoModRef;
+
+  // If the pointer is a pointer to constant memory, then it could not have been
+  // modified by this store.
+  if (pointsToConstantMemory(Loc))
+    return NoModRef;
+
+  // Otherwise, a store just writes.
+  return Mod;
+}
+
+AliasAnalysis::ModRefResult
+AliasAnalysis::getModRefInfo(const VAArgInst *V, const Location &Loc) {
+  // If the va_arg address cannot alias the pointer in question, then the
+  // specified memory cannot be accessed by the va_arg.
+  if (!alias(getLocation(V), Loc))
+    return NoModRef;
+
+  // If the pointer is a pointer to constant memory, then it could not have been
+  // modified by this va_arg.
+  if (pointsToConstantMemory(Loc))
+    return NoModRef;
+
+  // Otherwise, a va_arg reads and writes.
+  return ModRef;
+}
+
+AliasAnalysis::ModRefResult
+AliasAnalysis::getModRefInfo(const AtomicCmpXchgInst *CX, const Location &Loc) {
+  // Acquire/Release cmpxchg has properties that matter for arbitrary addresses.
+  if (CX->getOrdering() > Monotonic)
+    return ModRef;
+
+  // If the cmpxchg address does not alias the location, it does not access it.
+  if (!alias(getLocation(CX), Loc))
+    return NoModRef;
+
+  return ModRef;
+}
+
+AliasAnalysis::ModRefResult
+AliasAnalysis::getModRefInfo(const AtomicRMWInst *RMW, const Location &Loc) {
+  // Acquire/Release atomicrmw has properties that matter for arbitrary addresses.
+  if (RMW->getOrdering() > Monotonic)
+    return ModRef;
+
+  // If the atomicrmw address does not alias the location, it does not access it.
+  if (!alias(getLocation(RMW), Loc))
+    return NoModRef;
+
+  return ModRef;
+}
+
+namespace {
+  // Conservatively return true. Return false, if there is a single path
+  // starting from "From" and the path does not reach "To".
+  static bool hasPath(const BasicBlock *From, const BasicBlock *To) {
+    const unsigned MaxCheck = 5;
+    const BasicBlock *Current = From;
+    for (unsigned I = 0; I < MaxCheck; I++) {
+      unsigned NumSuccs = Current->getTerminator()->getNumSuccessors();
+      if (NumSuccs > 1)
+        return true;
+      if (NumSuccs == 0)
+        return false;
+      Current = Current->getTerminator()->getSuccessor(0);
+      if (Current == To)
+        return true;
+    }
+    return true;
+  }
+
+  /// Only find pointer captures which happen before the given instruction. Uses
+  /// the dominator tree to determine whether one instruction is before another.
+  /// Only support the case where the Value is defined in the same basic block
+  /// as the given instruction and the use.
+  struct CapturesBefore : public CaptureTracker {
+    CapturesBefore(const Instruction *I, DominatorTree *DT)
+      : BeforeHere(I), DT(DT), Captured(false) {}
+
+    void tooManyUses() { Captured = true; }
+
+    bool shouldExplore(Use *U) {
+      Instruction *I = cast<Instruction>(U->getUser());
+      BasicBlock *BB = I->getParent();
+      // We explore this usage only if the usage can reach "BeforeHere".
+      // If use is not reachable from entry, there is no need to explore.
+      if (BeforeHere != I && !DT->isReachableFromEntry(BB))
+        return false;
+      // If the value is defined in the same basic block as use and BeforeHere,
+      // there is no need to explore the use if BeforeHere dominates use.
+      // Check whether there is a path from I to BeforeHere.
+      if (BeforeHere != I && DT->dominates(BeforeHere, I) &&
+          !hasPath(BB, BeforeHere->getParent()))
+        return false;
+      return true;
+    }
+
+    bool captured(Use *U) {
+      Instruction *I = cast<Instruction>(U->getUser());
+      BasicBlock *BB = I->getParent();
+      // Same logic as in shouldExplore.
+      if (BeforeHere != I && !DT->isReachableFromEntry(BB))
+        return false;
+      if (BeforeHere != I && DT->dominates(BeforeHere, I) &&
+          !hasPath(BB, BeforeHere->getParent()))
+        return false;
+      Captured = true;
+      return true;
+    }
+
+    const Instruction *BeforeHere;
+    DominatorTree *DT;
+
+    bool Captured;
+  };
+}
+
+// FIXME: this is really just shoring-up a deficiency in alias analysis.
+// BasicAA isn't willing to spend linear time determining whether an alloca
+// was captured before or after this particular call, while we are. However,
+// with a smarter AA in place, this test is just wasting compile time.
+AliasAnalysis::ModRefResult
+AliasAnalysis::callCapturesBefore(const Instruction *I,
+                                  const AliasAnalysis::Location &MemLoc,
+                                  DominatorTree *DT) {
+  if (!DT || !TD) return AliasAnalysis::ModRef;
+
+  const Value *Object = GetUnderlyingObject(MemLoc.Ptr, TD);
+  if (!isIdentifiedObject(Object) || isa<GlobalValue>(Object) ||
+      isa<Constant>(Object))
+    return AliasAnalysis::ModRef;
+
+  ImmutableCallSite CS(I);
+  if (!CS.getInstruction() || CS.getInstruction() == Object)
+    return AliasAnalysis::ModRef;
+
+  CapturesBefore CB(I, DT);
+  llvm::PointerMayBeCaptured(Object, &CB);
+  if (CB.Captured)
+    return AliasAnalysis::ModRef;
+
+  unsigned ArgNo = 0;
+  for (ImmutableCallSite::arg_iterator CI = CS.arg_begin(), CE = CS.arg_end();
+       CI != CE; ++CI, ++ArgNo) {
+    // Only look at the no-capture or byval pointer arguments.  If this
+    // pointer were passed to arguments that were neither of these, then it
+    // couldn't be no-capture.
+    if (!(*CI)->getType()->isPointerTy() ||
+        (!CS.doesNotCapture(ArgNo) && !CS.isByValArgument(ArgNo)))
+      continue;
+
+    // If this is a no-capture pointer argument, see if we can tell that it
+    // is impossible to alias the pointer we're checking.  If not, we have to
+    // assume that the call could touch the pointer, even though it doesn't
+    // escape.
+    if (!isNoAlias(AliasAnalysis::Location(*CI),
+                   AliasAnalysis::Location(Object))) {
+      return AliasAnalysis::ModRef;
+    }
+  }
+  return AliasAnalysis::NoModRef;
+}
+
+// AliasAnalysis destructor: DO NOT move this to the header file for
+// AliasAnalysis or else clients of the AliasAnalysis class may not depend on
+// the AliasAnalysis.o file in the current .a file, causing alias analysis
+// support to not be included in the tool correctly!
+//
+AliasAnalysis::~AliasAnalysis() {}
+
+/// InitializeAliasAnalysis - Subclasses must call this method to initialize the
+/// AliasAnalysis interface before any other methods are called.
+///
+void AliasAnalysis::InitializeAliasAnalysis(Pass *P) {
+  TD = P->getAnalysisIfAvailable<DataLayout>();
+  TLI = P->getAnalysisIfAvailable<TargetLibraryInfo>();
+  AA = &P->getAnalysis<AliasAnalysis>();
+}
+
+// getAnalysisUsage - All alias analysis implementations should invoke this
+// directly (using AliasAnalysis::getAnalysisUsage(AU)).
+void AliasAnalysis::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.addRequired<AliasAnalysis>();         // All AA's chain
+}
+
+/// getTypeStoreSize - Return the DataLayout store size for the given type,
+/// if known, or a conservative value otherwise.
+///
+uint64_t AliasAnalysis::getTypeStoreSize(Type *Ty) {
+  return TD ? TD->getTypeStoreSize(Ty) : UnknownSize;
+}
+
+/// canBasicBlockModify - Return true if it is possible for execution of the
+/// specified basic block to modify the value pointed to by Ptr.
+///
+bool AliasAnalysis::canBasicBlockModify(const BasicBlock &BB,
+                                        const Location &Loc) {
+  return canInstructionRangeModify(BB.front(), BB.back(), Loc);
+}
+
+/// canInstructionRangeModify - Return true if it is possible for the execution
+/// of the specified instructions to modify the value pointed to by Ptr.  The
+/// instructions to consider are all of the instructions in the range of [I1,I2]
+/// INCLUSIVE.  I1 and I2 must be in the same basic block.
+///
+bool AliasAnalysis::canInstructionRangeModify(const Instruction &I1,
+                                              const Instruction &I2,
+                                              const Location &Loc) {
+  assert(I1.getParent() == I2.getParent() &&
+         "Instructions not in same basic block!");
+  BasicBlock::const_iterator I = &I1;
+  BasicBlock::const_iterator E = &I2;
+  ++E;  // Convert from inclusive to exclusive range.
+
+  for (; I != E; ++I) // Check every instruction in range
+    if (getModRefInfo(I, Loc) & Mod)
+      return true;
+  return false;
+}
+
+/// isNoAliasCall - Return true if this pointer is returned by a noalias
+/// function.
+bool llvm::isNoAliasCall(const Value *V) {
+  if (isa<CallInst>(V) || isa<InvokeInst>(V))
+    return ImmutableCallSite(cast<Instruction>(V))
+      .paramHasAttr(0, Attribute::NoAlias);
+  return false;
+}
+
+/// isIdentifiedObject - Return true if this pointer refers to a distinct and
+/// identifiable object.  This returns true for:
+///    Global Variables and Functions (but not Global Aliases)
+///    Allocas and Mallocs
+///    ByVal and NoAlias Arguments
+///    NoAlias returns
+///
+bool llvm::isIdentifiedObject(const Value *V) {
+  if (isa<AllocaInst>(V))
+    return true;
+  if (isa<GlobalValue>(V) && !isa<GlobalAlias>(V))
+    return true;
+  if (isNoAliasCall(V))
+    return true;
+  if (const Argument *A = dyn_cast<Argument>(V))
+    return A->hasNoAliasAttr() || A->hasByValAttr();
+  return false;
+}