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diff --git a/contrib/llvm/tools/clang/lib/CodeGen/CGException.h b/contrib/llvm/tools/clang/lib/CodeGen/CGException.h
new file mode 100644
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+++ b/contrib/llvm/tools/clang/lib/CodeGen/CGException.h
@@ -0,0 +1,428 @@
+//===-- CGException.h - Classes for exceptions IR generation ----*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// These classes support the generation of LLVM IR for exceptions in
+// C++ and Objective C.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef CLANG_CODEGEN_CGEXCEPTION_H
+#define CLANG_CODEGEN_CGEXCEPTION_H
+
+/// EHScopeStack is defined in CodeGenFunction.h, but its
+/// implementation is in this file and in CGException.cpp.
+#include "CodeGenFunction.h"
+
+namespace llvm {
+  class Value;
+  class BasicBlock;
+}
+
+namespace clang {
+namespace CodeGen {
+
+/// A protected scope for zero-cost EH handling.
+class EHScope {
+  llvm::BasicBlock *CachedLandingPad;
+
+  unsigned K : 3;
+
+protected:
+  enum { BitsRemaining = 29 };
+
+public:
+  enum Kind { Cleanup, LazyCleanup, Catch, Terminate, Filter };
+
+  EHScope(Kind K) : CachedLandingPad(0), K(K) {}
+
+  Kind getKind() const { return static_cast<Kind>(K); }
+
+  llvm::BasicBlock *getCachedLandingPad() const {
+    return CachedLandingPad;
+  }
+
+  void setCachedLandingPad(llvm::BasicBlock *Block) {
+    CachedLandingPad = Block;
+  }
+};
+
+/// A scope which attempts to handle some, possibly all, types of
+/// exceptions.
+///
+/// Objective C @finally blocks are represented using a cleanup scope
+/// after the catch scope.
+class EHCatchScope : public EHScope {
+  unsigned NumHandlers : BitsRemaining;
+
+  // In effect, we have a flexible array member
+  //   Handler Handlers[0];
+  // But that's only standard in C99, not C++, so we have to do
+  // annoying pointer arithmetic instead.
+
+public:
+  struct Handler {
+    /// A type info value, or null (C++ null, not an LLVM null pointer)
+    /// for a catch-all.
+    llvm::Value *Type;
+
+    /// The catch handler for this type.
+    llvm::BasicBlock *Block;
+
+    static Handler make(llvm::Value *Type, llvm::BasicBlock *Block) {
+      Handler Temp;
+      Temp.Type = Type;
+      Temp.Block = Block;
+      return Temp;
+    }
+  };
+
+private:
+  Handler *getHandlers() {
+    return reinterpret_cast<Handler*>(this+1);
+  }
+
+  const Handler *getHandlers() const {
+    return reinterpret_cast<const Handler*>(this+1);
+  }
+
+public:
+  static size_t getSizeForNumHandlers(unsigned N) {
+    return sizeof(EHCatchScope) + N * sizeof(Handler);
+  }
+
+  EHCatchScope(unsigned NumHandlers)
+    : EHScope(Catch), NumHandlers(NumHandlers) {
+  }
+
+  unsigned getNumHandlers() const {
+    return NumHandlers;
+  }
+
+  void setCatchAllHandler(unsigned I, llvm::BasicBlock *Block) {
+    setHandler(I, /*catchall*/ 0, Block);
+  }
+
+  void setHandler(unsigned I, llvm::Value *Type, llvm::BasicBlock *Block) {
+    assert(I < getNumHandlers());
+    getHandlers()[I] = Handler::make(Type, Block);
+  }
+
+  const Handler &getHandler(unsigned I) const {
+    assert(I < getNumHandlers());
+    return getHandlers()[I];
+  }
+
+  typedef const Handler *iterator;
+  iterator begin() const { return getHandlers(); }
+  iterator end() const { return getHandlers() + getNumHandlers(); }
+
+  static bool classof(const EHScope *Scope) {
+    return Scope->getKind() == Catch;
+  }
+};
+
+/// A cleanup scope which generates the cleanup blocks lazily.
+class EHLazyCleanupScope : public EHScope {
+  /// Whether this cleanup needs to be run along normal edges.
+  bool IsNormalCleanup : 1;
+
+  /// Whether this cleanup needs to be run along exception edges.
+  bool IsEHCleanup : 1;
+
+  /// The amount of extra storage needed by the LazyCleanup.
+  /// Always a multiple of the scope-stack alignment.
+  unsigned CleanupSize : 12;
+
+  /// The number of fixups required by enclosing scopes (not including
+  /// this one).  If this is the top cleanup scope, all the fixups
+  /// from this index onwards belong to this scope.
+  unsigned FixupDepth : BitsRemaining - 14;
+
+  /// The nearest normal cleanup scope enclosing this one.
+  EHScopeStack::stable_iterator EnclosingNormal;
+
+  /// The nearest EH cleanup scope enclosing this one.
+  EHScopeStack::stable_iterator EnclosingEH;
+
+  /// The dual entry/exit block along the normal edge.  This is lazily
+  /// created if needed before the cleanup is popped.
+  llvm::BasicBlock *NormalBlock;
+
+  /// The dual entry/exit block along the EH edge.  This is lazily
+  /// created if needed before the cleanup is popped.
+  llvm::BasicBlock *EHBlock;
+
+public:
+  /// Gets the size required for a lazy cleanup scope with the given
+  /// cleanup-data requirements.
+  static size_t getSizeForCleanupSize(size_t Size) {
+    return sizeof(EHLazyCleanupScope) + Size;
+  }
+
+  size_t getAllocatedSize() const {
+    return sizeof(EHLazyCleanupScope) + CleanupSize;
+  }
+
+  EHLazyCleanupScope(bool IsNormal, bool IsEH, unsigned CleanupSize,
+                     unsigned FixupDepth,
+                     EHScopeStack::stable_iterator EnclosingNormal,
+                     EHScopeStack::stable_iterator EnclosingEH)
+    : EHScope(EHScope::LazyCleanup),
+      IsNormalCleanup(IsNormal), IsEHCleanup(IsEH),
+      CleanupSize(CleanupSize), FixupDepth(FixupDepth),
+      EnclosingNormal(EnclosingNormal), EnclosingEH(EnclosingEH),
+      NormalBlock(0), EHBlock(0)
+  {}
+
+  bool isNormalCleanup() const { return IsNormalCleanup; }
+  llvm::BasicBlock *getNormalBlock() const { return NormalBlock; }
+  void setNormalBlock(llvm::BasicBlock *BB) { NormalBlock = BB; }
+
+  bool isEHCleanup() const { return IsEHCleanup; }
+  llvm::BasicBlock *getEHBlock() const { return EHBlock; }
+  void setEHBlock(llvm::BasicBlock *BB) { EHBlock = BB; }
+
+  unsigned getFixupDepth() const { return FixupDepth; }
+  EHScopeStack::stable_iterator getEnclosingNormalCleanup() const {
+    return EnclosingNormal;
+  }
+  EHScopeStack::stable_iterator getEnclosingEHCleanup() const {
+    return EnclosingEH;
+  }
+
+  size_t getCleanupSize() const { return CleanupSize; }
+  void *getCleanupBuffer() { return this + 1; }
+
+  EHScopeStack::LazyCleanup *getCleanup() {
+    return reinterpret_cast<EHScopeStack::LazyCleanup*>(getCleanupBuffer());
+  }
+
+  static bool classof(const EHScope *Scope) {
+    return (Scope->getKind() == LazyCleanup);
+  }
+};
+
+/// A scope which needs to execute some code if we try to unwind ---
+/// either normally, via the EH mechanism, or both --- through it.
+class EHCleanupScope : public EHScope {
+  /// The number of fixups required by enclosing scopes (not including
+  /// this one).  If this is the top cleanup scope, all the fixups
+  /// from this index onwards belong to this scope.
+  unsigned FixupDepth : BitsRemaining;
+
+  /// The nearest normal cleanup scope enclosing this one.
+  EHScopeStack::stable_iterator EnclosingNormal;
+
+  /// The nearest EH cleanup scope enclosing this one.
+  EHScopeStack::stable_iterator EnclosingEH;
+
+  llvm::BasicBlock *NormalEntry;
+  llvm::BasicBlock *NormalExit;
+  llvm::BasicBlock *EHEntry;
+  llvm::BasicBlock *EHExit;
+
+public:
+  static size_t getSize() { return sizeof(EHCleanupScope); }
+
+  EHCleanupScope(unsigned FixupDepth,
+                 EHScopeStack::stable_iterator EnclosingNormal,
+                 EHScopeStack::stable_iterator EnclosingEH,
+                 llvm::BasicBlock *NormalEntry, llvm::BasicBlock *NormalExit,
+                 llvm::BasicBlock *EHEntry, llvm::BasicBlock *EHExit)
+    : EHScope(Cleanup), FixupDepth(FixupDepth),
+      EnclosingNormal(EnclosingNormal), EnclosingEH(EnclosingEH),
+      NormalEntry(NormalEntry), NormalExit(NormalExit),
+      EHEntry(EHEntry), EHExit(EHExit) {
+    assert((NormalEntry != 0) == (NormalExit != 0));
+    assert((EHEntry != 0) == (EHExit != 0));
+  }
+
+  bool isNormalCleanup() const { return NormalEntry != 0; }
+  bool isEHCleanup() const { return EHEntry != 0; }
+
+  llvm::BasicBlock *getNormalEntry() const { return NormalEntry; }
+  llvm::BasicBlock *getNormalExit() const { return NormalExit; }
+  llvm::BasicBlock *getEHEntry() const { return EHEntry; }
+  llvm::BasicBlock *getEHExit() const { return EHExit; }
+  unsigned getFixupDepth() const { return FixupDepth; }
+  EHScopeStack::stable_iterator getEnclosingNormalCleanup() const {
+    return EnclosingNormal;
+  }
+  EHScopeStack::stable_iterator getEnclosingEHCleanup() const {
+    return EnclosingEH;
+  }
+
+  static bool classof(const EHScope *Scope) {
+    return Scope->getKind() == Cleanup;
+  }
+};
+
+/// An exceptions scope which filters exceptions thrown through it.
+/// Only exceptions matching the filter types will be permitted to be
+/// thrown.
+///
+/// This is used to implement C++ exception specifications.
+class EHFilterScope : public EHScope {
+  unsigned NumFilters : BitsRemaining;
+
+  // Essentially ends in a flexible array member:
+  // llvm::Value *FilterTypes[0];
+
+  llvm::Value **getFilters() {
+    return reinterpret_cast<llvm::Value**>(this+1);
+  }
+
+  llvm::Value * const *getFilters() const {
+    return reinterpret_cast<llvm::Value* const *>(this+1);
+  }
+
+public:
+  EHFilterScope(unsigned NumFilters) :
+    EHScope(Filter), NumFilters(NumFilters) {}
+
+  static size_t getSizeForNumFilters(unsigned NumFilters) {
+    return sizeof(EHFilterScope) + NumFilters * sizeof(llvm::Value*);
+  }
+
+  unsigned getNumFilters() const { return NumFilters; }
+
+  void setFilter(unsigned I, llvm::Value *FilterValue) {
+    assert(I < getNumFilters());
+    getFilters()[I] = FilterValue;
+  }
+
+  llvm::Value *getFilter(unsigned I) const {
+    assert(I < getNumFilters());
+    return getFilters()[I];
+  }
+
+  static bool classof(const EHScope *Scope) {
+    return Scope->getKind() == Filter;
+  }
+};
+
+/// An exceptions scope which calls std::terminate if any exception
+/// reaches it.
+class EHTerminateScope : public EHScope {
+public:
+  EHTerminateScope() : EHScope(Terminate) {}
+  static size_t getSize() { return sizeof(EHTerminateScope); }
+
+  static bool classof(const EHScope *Scope) {
+    return Scope->getKind() == Terminate;
+  }
+};
+
+/// A non-stable pointer into the scope stack.
+class EHScopeStack::iterator {
+  char *Ptr;
+
+  friend class EHScopeStack;
+  explicit iterator(char *Ptr) : Ptr(Ptr) {}
+
+public:
+  iterator() : Ptr(0) {}
+
+  EHScope *get() const { 
+    return reinterpret_cast<EHScope*>(Ptr);
+  }
+
+  EHScope *operator->() const { return get(); }
+  EHScope &operator*() const { return *get(); }
+
+  iterator &operator++() {
+    switch (get()->getKind()) {
+    case EHScope::Catch:
+      Ptr += EHCatchScope::getSizeForNumHandlers(
+          static_cast<const EHCatchScope*>(get())->getNumHandlers());
+      break;
+
+    case EHScope::Filter:
+      Ptr += EHFilterScope::getSizeForNumFilters(
+          static_cast<const EHFilterScope*>(get())->getNumFilters());
+      break;
+
+    case EHScope::LazyCleanup:
+      Ptr += static_cast<const EHLazyCleanupScope*>(get())
+        ->getAllocatedSize();
+      break;
+
+    case EHScope::Cleanup:
+      Ptr += EHCleanupScope::getSize();
+      break;
+
+    case EHScope::Terminate:
+      Ptr += EHTerminateScope::getSize();
+      break;
+    }
+
+    return *this;
+  }
+
+  iterator next() {
+    iterator copy = *this;
+    ++copy;
+    return copy;
+  }
+
+  iterator operator++(int) {
+    iterator copy = *this;
+    operator++();
+    return copy;
+  }
+
+  bool operator==(iterator other) const { return Ptr == other.Ptr; }
+  bool operator!=(iterator other) const { return Ptr != other.Ptr; }
+};
+
+inline EHScopeStack::iterator EHScopeStack::begin() const {
+  return iterator(StartOfData);
+}
+
+inline EHScopeStack::iterator EHScopeStack::end() const {
+  return iterator(EndOfBuffer);
+}
+
+inline void EHScopeStack::popCatch() {
+  assert(!empty() && "popping exception stack when not empty");
+
+  assert(isa<EHCatchScope>(*begin()));
+  StartOfData += EHCatchScope::getSizeForNumHandlers(
+                          cast<EHCatchScope>(*begin()).getNumHandlers());
+
+  assert(CatchDepth > 0 && "mismatched catch/terminate push/pop");
+  CatchDepth--;
+}
+
+inline void EHScopeStack::popTerminate() {
+  assert(!empty() && "popping exception stack when not empty");
+
+  assert(isa<EHTerminateScope>(*begin()));
+  StartOfData += EHTerminateScope::getSize();
+
+  assert(CatchDepth > 0 && "mismatched catch/terminate push/pop");
+  CatchDepth--;
+}
+
+inline EHScopeStack::iterator EHScopeStack::find(stable_iterator sp) const {
+  assert(sp.isValid() && "finding invalid savepoint");
+  assert(sp.Size <= stable_begin().Size && "finding savepoint after pop");
+  return iterator(EndOfBuffer - sp.Size);
+}
+
+inline EHScopeStack::stable_iterator
+EHScopeStack::stabilize(iterator ir) const {
+  assert(StartOfData <= ir.Ptr && ir.Ptr <= EndOfBuffer);
+  return stable_iterator(EndOfBuffer - ir.Ptr);
+}
+
+}
+}
+
+#endif