Imported Upstream version 5.18.0.167

Former-commit-id: 289509151e0fee68a1b591a20c9f109c3c789d3a

external/llvm/utils/TableGen/SequenceToOffsetTable.h

@@ -1,146 +0,0 @@
-//===-- SequenceToOffsetTable.h - Compress similar sequences ----*- C++ -*-===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// SequenceToOffsetTable can be used to emit a number of null-terminated
-// sequences as one big array.  Use the same memory when a sequence is a suffix
-// of another.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLVM_UTILS_TABLEGEN_SEQUENCETOOFFSETTABLE_H
-#define LLVM_UTILS_TABLEGEN_SEQUENCETOOFFSETTABLE_H
-
-#include "llvm/Support/raw_ostream.h"
-#include <algorithm>
-#include <cassert>
-#include <cctype>
-#include <functional>
-#include <map>
-
-namespace llvm {
-
-/// SequenceToOffsetTable - Collect a number of terminated sequences of T.
-/// Compute the layout of a table that contains all the sequences, possibly by
-/// reusing entries.
-///
-/// @tparam SeqT The sequence container. (vector or string).
-/// @tparam Less A stable comparator for SeqT elements.
-template<typename SeqT, typename Less = std::less<typename SeqT::value_type> >
-class SequenceToOffsetTable {
-  typedef typename SeqT::value_type ElemT;
-
-  // Define a comparator for SeqT that sorts a suffix immediately before a
-  // sequence with that suffix.
-  struct SeqLess {
-    Less L;
-    bool operator()(const SeqT &A, const SeqT &B) const {
-      return std::lexicographical_compare(A.rbegin(), A.rend(),
-                                          B.rbegin(), B.rend(), L);
-    }
-  };
-
-  // Keep sequences ordered according to SeqLess so suffixes are easy to find.
-  // Map each sequence to its offset in the table.
-  typedef std::map<SeqT, unsigned, SeqLess> SeqMap;
-
-  // Sequences added so far, with suffixes removed.
-  SeqMap Seqs;
-
-  // Entries in the final table, or 0 before layout was called.
-  unsigned Entries;
-
-  // isSuffix - Returns true if A is a suffix of B.
-  static bool isSuffix(const SeqT &A, const SeqT &B) {
-    return A.size() <= B.size() && std::equal(A.rbegin(), A.rend(), B.rbegin());
-  }
-
-public:
-  SequenceToOffsetTable() : Entries(0) {}
-
-  /// add - Add a sequence to the table.
-  /// This must be called before layout().
-  void add(const SeqT &Seq) {
-    assert(Entries == 0 && "Cannot call add() after layout()");
-    typename SeqMap::iterator I = Seqs.lower_bound(Seq);
-
-    // If SeqMap contains a sequence that has Seq as a suffix, I will be
-    // pointing to it.
-    if (I != Seqs.end() && isSuffix(Seq, I->first))
-      return;
-
-    I = Seqs.insert(I, std::make_pair(Seq, 0u));
-
-    // The entry before I may be a suffix of Seq that can now be erased.
-    if (I != Seqs.begin() && isSuffix((--I)->first, Seq))
-      Seqs.erase(I);
-  }
-
-  bool empty() const { return Seqs.empty(); }
-
-  unsigned size() const {
-    assert(Entries && "Call layout() before size()");
-    return Entries;
-  }
-
-  /// layout - Computes the final table layout.
-  void layout() {
-    assert(Entries == 0 && "Can only call layout() once");
-    // Lay out the table in Seqs iteration order.
-    for (typename SeqMap::iterator I = Seqs.begin(), E = Seqs.end(); I != E;
-         ++I) {
-      I->second = Entries;
-      // Include space for a terminator.
-      Entries += I->first.size() + 1;
-    }
-  }
-
-  /// get - Returns the offset of Seq in the final table.
-  unsigned get(const SeqT &Seq) const {
-    assert(Entries && "Call layout() before get()");
-    typename SeqMap::const_iterator I = Seqs.lower_bound(Seq);
-    assert(I != Seqs.end() && isSuffix(Seq, I->first) &&
-           "get() called with sequence that wasn't added first");
-    return I->second + (I->first.size() - Seq.size());
-  }
-
-  /// emit - Print out the table as the body of an array initializer.
-  /// Use the Print function to print elements.
-  void emit(raw_ostream &OS,
-            void (*Print)(raw_ostream&, ElemT),
-            const char *Term = "0") const {
-    assert(Entries && "Call layout() before emit()");
-    for (typename SeqMap::const_iterator I = Seqs.begin(), E = Seqs.end();
-         I != E; ++I) {
-      OS << "  /* " << I->second << " */ ";
-      for (typename SeqT::const_iterator SI = I->first.begin(),
-             SE = I->first.end(); SI != SE; ++SI) {
-        Print(OS, *SI);
-        OS << ", ";
-      }
-      OS << Term << ",\n";
-    }
-  }
-};
-
-// Helper function for SequenceToOffsetTable<string>.
-static inline void printChar(raw_ostream &OS, char C) {
-  unsigned char UC(C);
-  if (isalnum(UC) || ispunct(UC)) {
-    OS << '\'';
-    if (C == '\\' || C == '\'')
-      OS << '\\';
-    OS << C << '\'';
-  } else {
-    OS << unsigned(UC);
-  }
-}
-
-} // end namespace llvm
-
-#endif