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//===- llvm/ADT/IndexedMap.h - An index map implementation ------*- C++ -*-===//
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// The LLVM Compiler Infrastructure
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//===----------------------------------------------------------------------===//
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// This file implements an indexed map. The index map template takes two
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// types. The first is the mapped type and the second is a functor
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// that maps its argument to a size_t. On instantiation a "null" value
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// can be provided to be used as a "does not exist" indicator in the
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// map. A member function grow() is provided that given the value of
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// the maximally indexed key (the argument of the functor) makes sure
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// the map has enough space for it.
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_ADT_INDEXEDMAP_H
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#define LLVM_ADT_INDEXEDMAP_H
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struct IdentityFunctor : public std::unary_function<unsigned, unsigned> {
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unsigned operator()(unsigned Index) const {
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template <typename T, typename ToIndexT = IdentityFunctor>
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typedef typename ToIndexT::argument_type IndexT;
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typedef std::vector<T> StorageT;
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IndexedMap() : nullVal_(T()) { }
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explicit IndexedMap(const T& val) : nullVal_(val) { }
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typename StorageT::reference operator[](IndexT n) {
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assert(toIndex_(n) < storage_.size() && "index out of bounds!");
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return storage_[toIndex_(n)];
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typename StorageT::const_reference operator[](IndexT n) const {
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assert(toIndex_(n) < storage_.size() && "index out of bounds!");
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return storage_[toIndex_(n)];
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unsigned NewSize = toIndex_(n) + 1;
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if (NewSize > storage_.size())
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storage_.resize(NewSize, nullVal_);
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typename StorageT::size_type size() const {
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return storage_.size();
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} // End llvm namespace