lldb/include/lldb/Symbol/LineTable.h - llvm-project - Git at Google

 //===-- LineTable.h ---------------------------------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//

 #ifndef LLDB_SYMBOL_LINETABLE_H
 #define LLDB_SYMBOL_LINETABLE_H

 #include "lldb/Core/Address.h"
 #include "lldb/Core/ModuleChild.h"
 #include "lldb/Core/Section.h"
 #include "lldb/Core/SourceLocationSpec.h"
 #include "lldb/Symbol/LineEntry.h"
 #include "lldb/Utility/RangeMap.h"
 #include "lldb/lldb-private.h"
 #include <vector>

 namespace lldb_private {

 /// \class LineSequence LineTable.h "lldb/Symbol/LineTable.h" An abstract base
 /// class used during symbol table creation.
 class LineSequence {
 public:
   LineSequence();

   virtual ~LineSequence() = default;

   virtual void Clear() = 0;

 private:
   LineSequence(const LineSequence &) = delete;
   const LineSequence &operator=(const LineSequence &) = delete;
 };

 /// \class LineTable LineTable.h "lldb/Symbol/LineTable.h"
 /// A line table class.
 class LineTable {
 public:
   /// Construct with compile unit.
   ///
   /// \param[in] comp_unit
   ///     The compile unit to which this line table belongs.
   LineTable(CompileUnit *comp_unit);

   /// Construct with entries found in \a sequences.
   ///
   /// \param[in] sequences
   ///     Unsorted list of line sequences.
   LineTable(CompileUnit *comp_unit,
             std::vector<std::unique_ptr<LineSequence>> &&sequences);

   /// Destructor.
   ~LineTable();

   /// Adds a new line entry to this line table.
   ///
   /// All line entries are maintained in file address order.
   ///
   /// \param[in] line_entry
   ///     A const reference to a new line_entry to add to this line
   ///     table.
   ///
   /// \see Address::DumpStyle
   //  void
   //  AddLineEntry (const LineEntry& line_entry);

   // Called when you can't guarantee the addresses are in increasing order
   void InsertLineEntry(lldb::addr_t file_addr, uint32_t line, uint16_t column,
                        uint16_t file_idx, bool is_start_of_statement,
                        bool is_start_of_basic_block, bool is_prologue_end,
                        bool is_epilogue_begin, bool is_terminal_entry);

   // Used to instantiate the LineSequence helper class
   static std::unique_ptr<LineSequence> CreateLineSequenceContainer();

   // Append an entry to a caller-provided collection that will later be
   // inserted in this line table.
   static void AppendLineEntryToSequence(LineSequence *sequence, lldb::addr_t file_addr,
                                  uint32_t line, uint16_t column,
                                  uint16_t file_idx, bool is_start_of_statement,
                                  bool is_start_of_basic_block,
                                  bool is_prologue_end, bool is_epilogue_begin,
                                  bool is_terminal_entry);

   // Insert a sequence of entries into this line table.
   void InsertSequence(LineSequence *sequence);

   /// Dump all line entries in this line table to the stream \a s.
   ///
   /// \param[in] s
   ///     The stream to which to dump the object description.
   ///
   /// \param[in] style
   ///     The display style for the address.
   ///
   /// \see Address::DumpStyle
   void Dump(Stream *s, Target *target, Address::DumpStyle style,
             Address::DumpStyle fallback_style, bool show_line_ranges);

   void GetDescription(Stream *s, Target *target, lldb::DescriptionLevel level);

   /// Find a line entry that contains the section offset address \a so_addr.
   ///
   /// \param[in] so_addr
   ///     A section offset address object containing the address we
   ///     are searching for.
   ///
   /// \param[out] line_entry
   ///     A copy of the line entry that was found if \b true is
   ///     returned, otherwise \a entry is left unmodified.
   ///
   /// \param[out] index_ptr
   ///     A pointer to a 32 bit integer that will get the actual line
   ///     entry index if it is not nullptr.
   ///
   /// \return
   ///     Returns \b true if \a so_addr is contained in a line entry
   ///     in this line table, \b false otherwise.
   bool FindLineEntryByAddress(const Address &so_addr, LineEntry &line_entry,
                               uint32_t *index_ptr = nullptr);

   /// Find a line entry index that has a matching file index and source line
   /// number.
   ///
   /// Finds the next line entry that has a matching \a file_idx and source
   /// line number \a line starting at the \a start_idx entries into the line
   /// entry collection.
   ///
   /// \param[in] start_idx
   ///     The number of entries to skip when starting the search.
   ///
   /// \param[out] file_idx
   ///     The file index to search for that should be found prior
   ///     to calling this function using the following functions:
   ///     CompileUnit::GetSupportFiles()
   ///     FileSpecList::FindFileIndex (uint32_t, const FileSpec &) const
   ///
   /// \param[in] src_location_spec
   ///     The source location specifier to match.
   ///
   /// \param[out] line_entry_ptr
   ///     A pointer to a line entry object that will get a copy of
   ///     the line entry if \b true is returned, otherwise \a
   ///     line_entry is left untouched.
   ///
   /// \return
   ///     Returns \b true if a matching line entry is found in this
   ///     line table, \b false otherwise.
   ///
   /// \see CompileUnit::GetSupportFiles()
   /// \see FileSpecList::FindFileIndex (uint32_t, const FileSpec &) const
   uint32_t
   FindLineEntryIndexByFileIndex(uint32_t start_idx, uint32_t file_idx,
                                 const SourceLocationSpec &src_location_spec,
                                 LineEntry *line_entry_ptr);

   uint32_t FindLineEntryIndexByFileIndex(
       uint32_t start_idx, const std::vector<uint32_t> &file_idx,
       const SourceLocationSpec &src_location_spec, LineEntry *line_entry_ptr);

   size_t FineLineEntriesForFileIndex(uint32_t file_idx, bool append,
                                      SymbolContextList &sc_list);

   /// Get the line entry from the line table at index \a idx.
   ///
   /// \param[in] idx
   ///     An index into the line table entry collection.
   ///
   /// \return
   ///     A valid line entry if \a idx is a valid index, or an invalid
   ///     line entry if \a idx is not valid.
   ///
   /// \see LineTable::GetSize()
   /// \see LineEntry::IsValid() const
   bool GetLineEntryAtIndex(uint32_t idx, LineEntry &line_entry);

   /// Gets the size of the line table in number of line table entries.
   ///
   /// \return
   ///     The number of line table entries in this line table.
   uint32_t GetSize() const;

   typedef lldb_private::RangeVector<lldb::addr_t, lldb::addr_t, 32>
       FileAddressRanges;

   /// Gets all contiguous file address ranges for the entire line table.
   ///
   /// \param[out] file_ranges
   ///     A collection of file address ranges that will be filled in
   ///     by this function.
   ///
   /// \param[out] append
   ///     If \b true, then append to \a file_ranges, otherwise clear
   ///     \a file_ranges prior to adding any ranges.
   ///
   /// \return
   ///     The number of address ranges added to \a file_ranges
   size_t GetContiguousFileAddressRanges(FileAddressRanges &file_ranges,
                                         bool append);

   typedef RangeDataVector<lldb::addr_t, lldb::addr_t, lldb::addr_t>
       FileRangeMap;

   LineTable *LinkLineTable(const FileRangeMap &file_range_map);

 protected:
   struct Entry {
     Entry()
         : line(0), is_start_of_statement(false), is_start_of_basic_block(false),
           is_prologue_end(false), is_epilogue_begin(false),
           is_terminal_entry(false) {}

     Entry(lldb::addr_t _file_addr, uint32_t _line, uint16_t _column,
           uint16_t _file_idx, bool _is_start_of_statement,
           bool _is_start_of_basic_block, bool _is_prologue_end,
           bool _is_epilogue_begin, bool _is_terminal_entry)
         : file_addr(_file_addr), line(_line),
           is_start_of_statement(_is_start_of_statement),
           is_start_of_basic_block(_is_start_of_basic_block),
           is_prologue_end(_is_prologue_end),
           is_epilogue_begin(_is_epilogue_begin),
           is_terminal_entry(_is_terminal_entry), column(_column),
           file_idx(_file_idx) {}

     int bsearch_compare(const void *key, const void *arrmem);

     void Clear() {
       file_addr = LLDB_INVALID_ADDRESS;
       line = 0;
       column = 0;
       file_idx = 0;
       is_start_of_statement = false;
       is_start_of_basic_block = false;
       is_prologue_end = false;
       is_epilogue_begin = false;
       is_terminal_entry = false;
     }

     static int Compare(const Entry &lhs, const Entry &rhs) {
 // Compare the sections before calling
 #define SCALAR_COMPARE(a, b)                                                   \
   if (a < b)                                                                   \
     return -1;                                                                 \
   if (a > b)                                                                   \
   return +1
       SCALAR_COMPARE(lhs.file_addr, rhs.file_addr);
       SCALAR_COMPARE(lhs.line, rhs.line);
       SCALAR_COMPARE(lhs.column, rhs.column);
       SCALAR_COMPARE(lhs.is_start_of_statement, rhs.is_start_of_statement);
       SCALAR_COMPARE(lhs.is_start_of_basic_block, rhs.is_start_of_basic_block);
       // rhs and lhs reversed on purpose below.
       SCALAR_COMPARE(rhs.is_prologue_end, lhs.is_prologue_end);
       SCALAR_COMPARE(lhs.is_epilogue_begin, rhs.is_epilogue_begin);
       // rhs and lhs reversed on purpose below.
       SCALAR_COMPARE(rhs.is_terminal_entry, lhs.is_terminal_entry);
       SCALAR_COMPARE(lhs.file_idx, rhs.file_idx);
 #undef SCALAR_COMPARE
       return 0;
     }

     class LessThanBinaryPredicate {
     public:
       LessThanBinaryPredicate(LineTable *line_table);
       bool operator()(const LineTable::Entry &, const LineTable::Entry &) const;
       bool operator()(const std::unique_ptr<LineSequence> &,
                       const std::unique_ptr<LineSequence> &) const;

     protected:
       LineTable *m_line_table;
     };

     static bool EntryAddressLessThan(const Entry &lhs, const Entry &rhs) {
       return lhs.file_addr < rhs.file_addr;
     }

     // Member variables.
     /// The file address for this line entry.
     lldb::addr_t file_addr = LLDB_INVALID_ADDRESS;
     /// The source line number, or zero if there is no line number
     /// information.
     uint32_t line : 27;
     /// Indicates this entry is the beginning of a statement.
     uint32_t is_start_of_statement : 1;
     /// Indicates this entry is the beginning of a basic block.
     uint32_t is_start_of_basic_block : 1;
     /// Indicates this entry is one (of possibly many) where execution
     /// should be suspended for an entry breakpoint of a function.
     uint32_t is_prologue_end : 1;
     /// Indicates this entry is one (of possibly many) where execution
     /// should be suspended for an exit breakpoint of a function.
     uint32_t is_epilogue_begin : 1;
     /// Indicates this entry is that of the first byte after the end
     /// of a sequence of target machine instructions.
     uint32_t is_terminal_entry : 1;
     /// The column number of the source line, or zero if there is no
     /// column information.
     uint16_t column = 0;
     /// The file index into CompileUnit's file table, or zero if there
     /// is no file information.
     uint16_t file_idx = 0;
   };

   struct EntrySearchInfo {
     LineTable *line_table;
     lldb_private::Section *a_section;
     Entry *a_entry;
   };

   // Types
   typedef std::vector<lldb_private::Section *>
       section_collection; ///< The collection type for the sections.
   typedef std::vector<Entry>
       entry_collection; ///< The collection type for the line entries.
   // Member variables.
   CompileUnit
       *m_comp_unit; ///< The compile unit that this line table belongs to.
   entry_collection
       m_entries; ///< The collection of line entries in this line table.

   // Helper class
   class LineSequenceImpl : public LineSequence {
   public:
     LineSequenceImpl() = default;

     ~LineSequenceImpl() override = default;

     void Clear() override;

     entry_collection
         m_entries; ///< The collection of line entries in this sequence.
   };

   bool ConvertEntryAtIndexToLineEntry(uint32_t idx, LineEntry &line_entry);

 private:
   LineTable(const LineTable &) = delete;
   const LineTable &operator=(const LineTable &) = delete;

   template <typename T>
   uint32_t FindLineEntryIndexByFileIndexImpl(
       uint32_t start_idx, T file_idx,
       const SourceLocationSpec &src_location_spec, LineEntry *line_entry_ptr,
       std::function<bool(T, uint16_t)> file_idx_matcher) {
     const size_t count = m_entries.size();
     size_t best_match = UINT32_MAX;

     if (!line_entry_ptr)
       return best_match;

     const uint32_t line = src_location_spec.GetLine().getValueOr(0);
     const uint16_t column =
         src_location_spec.GetColumn().getValueOr(LLDB_INVALID_COLUMN_NUMBER);
     const bool exact_match = src_location_spec.GetExactMatch();

     for (size_t idx = start_idx; idx < count; ++idx) {
       // Skip line table rows that terminate the previous row (is_terminal_entry
       // is non-zero)
       if (m_entries[idx].is_terminal_entry)
         continue;

       if (!file_idx_matcher(file_idx, m_entries[idx].file_idx))
         continue;

       // Exact match always wins.  Otherwise try to find the closest line > the
       // desired line.
       // FIXME: Maybe want to find the line closest before and the line closest
       // after and if they're not in the same function, don't return a match.

       if (column == LLDB_INVALID_COLUMN_NUMBER) {
         if (m_entries[idx].line < line) {
           continue;
         } else if (m_entries[idx].line == line) {
           ConvertEntryAtIndexToLineEntry(idx, *line_entry_ptr);
           return idx;
         } else if (!exact_match) {
           if (best_match == UINT32_MAX ||
               m_entries[idx].line < m_entries[best_match].line)
             best_match = idx;
         }
       } else {
         if (m_entries[idx].line < line) {
           continue;
         } else if (m_entries[idx].line == line &&
                    m_entries[idx].column == column) {
           ConvertEntryAtIndexToLineEntry(idx, *line_entry_ptr);
           return idx;
         } else if (!exact_match) {
           if (best_match == UINT32_MAX)
             best_match = idx;
           else if (m_entries[idx].line < m_entries[best_match].line)
             best_match = idx;
           else if (m_entries[idx].line == m_entries[best_match].line)
             if (m_entries[idx].column &&
                 m_entries[idx].column < m_entries[best_match].column)
               best_match = idx;
         }
       }
     }

     if (best_match != UINT32_MAX) {
       if (line_entry_ptr)
         ConvertEntryAtIndexToLineEntry(best_match, *line_entry_ptr);
       return best_match;
     }
     return UINT32_MAX;
   }
 };

 } // namespace lldb_private

 #endif // LLDB_SYMBOL_LINETABLE_H
	//===-- LineTable.h ---------------------------------------------- C++ --===//
	//
	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
	// See https://llvm.org/LICENSE.txt for license information.
	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
	//
	//===----------------------------------------------------------------------===//

	#ifndef LLDB_SYMBOL_LINETABLE_H
	#define LLDB_SYMBOL_LINETABLE_H

	#include "lldb/Core/Address.h"
	#include "lldb/Core/ModuleChild.h"
	#include "lldb/Core/Section.h"
	#include "lldb/Core/SourceLocationSpec.h"
	#include "lldb/Symbol/LineEntry.h"
	#include "lldb/Utility/RangeMap.h"
	#include "lldb/lldb-private.h"
	#include <vector>

	namespace lldb_private {

	/// \class LineSequence LineTable.h "lldb/Symbol/LineTable.h" An abstract base
	/// class used during symbol table creation.
	class LineSequence {
	public:
	LineSequence();

	virtual ~LineSequence() = default;

	virtual void Clear() = 0;

	private:
	LineSequence(const LineSequence &) = delete;
	const LineSequence &operator=(const LineSequence &) = delete;
	};

	/// \class LineTable LineTable.h "lldb/Symbol/LineTable.h"
	/// A line table class.
	class LineTable {
	public:
	/// Construct with compile unit.
	///
	/// \param[in] comp_unit
	/// The compile unit to which this line table belongs.
	LineTable(CompileUnit *comp_unit);

	/// Construct with entries found in \a sequences.
	///
	/// \param[in] sequences
	/// Unsorted list of line sequences.
	LineTable(CompileUnit *comp_unit,
	std::vector<std::unique_ptr<LineSequence>> &&sequences);

	/// Destructor.
	~LineTable();

	/// Adds a new line entry to this line table.
	///
	/// All line entries are maintained in file address order.
	///
	/// \param[in] line_entry
	/// A const reference to a new line_entry to add to this line
	/// table.
	///
	/// \see Address::DumpStyle
	// void
	// AddLineEntry (const LineEntry& line_entry);

	// Called when you can't guarantee the addresses are in increasing order
	void InsertLineEntry(lldb::addr_t file_addr, uint32_t line, uint16_t column,
	uint16_t file_idx, bool is_start_of_statement,
	bool is_start_of_basic_block, bool is_prologue_end,
	bool is_epilogue_begin, bool is_terminal_entry);

	// Used to instantiate the LineSequence helper class
	static std::unique_ptr<LineSequence> CreateLineSequenceContainer();

	// Append an entry to a caller-provided collection that will later be
	// inserted in this line table.
	static void AppendLineEntryToSequence(LineSequence *sequence, lldb::addr_t file_addr,
	uint32_t line, uint16_t column,
	uint16_t file_idx, bool is_start_of_statement,
	bool is_start_of_basic_block,
	bool is_prologue_end, bool is_epilogue_begin,
	bool is_terminal_entry);

	// Insert a sequence of entries into this line table.
	void InsertSequence(LineSequence *sequence);

	/// Dump all line entries in this line table to the stream \a s.
	///
	/// \param[in] s
	/// The stream to which to dump the object description.
	///
	/// \param[in] style
	/// The display style for the address.
	///
	/// \see Address::DumpStyle
	void Dump(Stream s, Target target, Address::DumpStyle style,
	Address::DumpStyle fallback_style, bool show_line_ranges);

	void GetDescription(Stream s, Target target, lldb::DescriptionLevel level);

	/// Find a line entry that contains the section offset address \a so_addr.
	///
	/// \param[in] so_addr
	/// A section offset address object containing the address we
	/// are searching for.
	///
	/// \param[out] line_entry
	/// A copy of the line entry that was found if \b true is
	/// returned, otherwise \a entry is left unmodified.
	///
	/// \param[out] index_ptr
	/// A pointer to a 32 bit integer that will get the actual line
	/// entry index if it is not nullptr.
	///
	/// \return
	/// Returns \b true if \a so_addr is contained in a line entry
	/// in this line table, \b false otherwise.
	bool FindLineEntryByAddress(const Address &so_addr, LineEntry &line_entry,
	uint32_t *index_ptr = nullptr);

	/// Find a line entry index that has a matching file index and source line
	/// number.
	///
	/// Finds the next line entry that has a matching \a file_idx and source
	/// line number \a line starting at the \a start_idx entries into the line
	/// entry collection.
	///
	/// \param[in] start_idx
	/// The number of entries to skip when starting the search.
	///
	/// \param[out] file_idx
	/// The file index to search for that should be found prior
	/// to calling this function using the following functions:
	/// CompileUnit::GetSupportFiles()
	/// FileSpecList::FindFileIndex (uint32_t, const FileSpec &) const
	///
	/// \param[in] src_location_spec
	/// The source location specifier to match.
	///
	/// \param[out] line_entry_ptr
	/// A pointer to a line entry object that will get a copy of
	/// the line entry if \b true is returned, otherwise \a
	/// line_entry is left untouched.
	///
	/// \return
	/// Returns \b true if a matching line entry is found in this
	/// line table, \b false otherwise.
	///
	/// \see CompileUnit::GetSupportFiles()
	/// \see FileSpecList::FindFileIndex (uint32_t, const FileSpec &) const
	uint32_t
	FindLineEntryIndexByFileIndex(uint32_t start_idx, uint32_t file_idx,
	const SourceLocationSpec &src_location_spec,
	LineEntry *line_entry_ptr);

	uint32_t FindLineEntryIndexByFileIndex(
	uint32_t start_idx, const std::vector<uint32_t> &file_idx,
	const SourceLocationSpec &src_location_spec, LineEntry *line_entry_ptr);

	size_t FineLineEntriesForFileIndex(uint32_t file_idx, bool append,
	SymbolContextList &sc_list);

	/// Get the line entry from the line table at index \a idx.
	///
	/// \param[in] idx
	/// An index into the line table entry collection.
	///
	/// \return
	/// A valid line entry if \a idx is a valid index, or an invalid
	/// line entry if \a idx is not valid.
	///
	/// \see LineTable::GetSize()
	/// \see LineEntry::IsValid() const
	bool GetLineEntryAtIndex(uint32_t idx, LineEntry &line_entry);

	/// Gets the size of the line table in number of line table entries.
	///
	/// \return
	/// The number of line table entries in this line table.
	uint32_t GetSize() const;

	typedef lldb_private::RangeVector<lldb::addr_t, lldb::addr_t, 32>
	FileAddressRanges;

	/// Gets all contiguous file address ranges for the entire line table.
	///
	/// \param[out] file_ranges
	/// A collection of file address ranges that will be filled in
	/// by this function.
	///
	/// \param[out] append
	/// If \b true, then append to \a file_ranges, otherwise clear
	/// \a file_ranges prior to adding any ranges.
	///
	/// \return
	/// The number of address ranges added to \a file_ranges
	size_t GetContiguousFileAddressRanges(FileAddressRanges &file_ranges,
	bool append);

	typedef RangeDataVector<lldb::addr_t, lldb::addr_t, lldb::addr_t>
	FileRangeMap;

	LineTable *LinkLineTable(const FileRangeMap &file_range_map);

	protected:
	struct Entry {
	Entry()
	: line(0), is_start_of_statement(false), is_start_of_basic_block(false),
	is_prologue_end(false), is_epilogue_begin(false),
	is_terminal_entry(false) {}

	Entry(lldb::addr_t _file_addr, uint32_t _line, uint16_t _column,
	uint16_t _file_idx, bool _is_start_of_statement,
	bool _is_start_of_basic_block, bool _is_prologue_end,
	bool _is_epilogue_begin, bool _is_terminal_entry)
	: file_addr(_file_addr), line(_line),
	is_start_of_statement(_is_start_of_statement),
	is_start_of_basic_block(_is_start_of_basic_block),
	is_prologue_end(_is_prologue_end),
	is_epilogue_begin(_is_epilogue_begin),
	is_terminal_entry(_is_terminal_entry), column(_column),
	file_idx(_file_idx) {}

	int bsearch_compare(const void key, const void arrmem);

	void Clear() {
	file_addr = LLDB_INVALID_ADDRESS;
	line = 0;
	column = 0;
	file_idx = 0;
	is_start_of_statement = false;
	is_start_of_basic_block = false;
	is_prologue_end = false;
	is_epilogue_begin = false;
	is_terminal_entry = false;
	}

	static int Compare(const Entry &lhs, const Entry &rhs) {
	// Compare the sections before calling
	#define SCALAR_COMPARE(a, b) \
	if (a < b) \
	return -1; \
	if (a > b) \
	return +1
	SCALAR_COMPARE(lhs.file_addr, rhs.file_addr);
	SCALAR_COMPARE(lhs.line, rhs.line);
	SCALAR_COMPARE(lhs.column, rhs.column);
	SCALAR_COMPARE(lhs.is_start_of_statement, rhs.is_start_of_statement);
	SCALAR_COMPARE(lhs.is_start_of_basic_block, rhs.is_start_of_basic_block);
	// rhs and lhs reversed on purpose below.
	SCALAR_COMPARE(rhs.is_prologue_end, lhs.is_prologue_end);
	SCALAR_COMPARE(lhs.is_epilogue_begin, rhs.is_epilogue_begin);
	// rhs and lhs reversed on purpose below.
	SCALAR_COMPARE(rhs.is_terminal_entry, lhs.is_terminal_entry);
	SCALAR_COMPARE(lhs.file_idx, rhs.file_idx);
	#undef SCALAR_COMPARE
	return 0;
	}

	class LessThanBinaryPredicate {
	public:
	LessThanBinaryPredicate(LineTable *line_table);
	bool operator()(const LineTable::Entry &, const LineTable::Entry &) const;
	bool operator()(const std::unique_ptr<LineSequence> &,
	const std::unique_ptr<LineSequence> &) const;

	protected:
	LineTable *m_line_table;
	};

	static bool EntryAddressLessThan(const Entry &lhs, const Entry &rhs) {
	return lhs.file_addr < rhs.file_addr;
	}

	// Member variables.
	/// The file address for this line entry.
	lldb::addr_t file_addr = LLDB_INVALID_ADDRESS;
	/// The source line number, or zero if there is no line number
	/// information.
	uint32_t line : 27;
	/// Indicates this entry is the beginning of a statement.
	uint32_t is_start_of_statement : 1;
	/// Indicates this entry is the beginning of a basic block.
	uint32_t is_start_of_basic_block : 1;
	/// Indicates this entry is one (of possibly many) where execution
	/// should be suspended for an entry breakpoint of a function.
	uint32_t is_prologue_end : 1;
	/// Indicates this entry is one (of possibly many) where execution
	/// should be suspended for an exit breakpoint of a function.
	uint32_t is_epilogue_begin : 1;
	/// Indicates this entry is that of the first byte after the end
	/// of a sequence of target machine instructions.
	uint32_t is_terminal_entry : 1;
	/// The column number of the source line, or zero if there is no
	/// column information.
	uint16_t column = 0;
	/// The file index into CompileUnit's file table, or zero if there
	/// is no file information.
	uint16_t file_idx = 0;
	};

	struct EntrySearchInfo {
	LineTable *line_table;
	lldb_private::Section *a_section;
	Entry *a_entry;
	};

	// Types
	typedef std::vector<lldb_private::Section *>
	section_collection; ///< The collection type for the sections.
	typedef std::vector<Entry>
	entry_collection; ///< The collection type for the line entries.
	// Member variables.
	CompileUnit
	*m_comp_unit; ///< The compile unit that this line table belongs to.
	entry_collection
	m_entries; ///< The collection of line entries in this line table.

	// Helper class
	class LineSequenceImpl : public LineSequence {
	public:
	LineSequenceImpl() = default;

	~LineSequenceImpl() override = default;

	void Clear() override;

	entry_collection
	m_entries; ///< The collection of line entries in this sequence.
	};

	bool ConvertEntryAtIndexToLineEntry(uint32_t idx, LineEntry &line_entry);

	private:
	LineTable(const LineTable &) = delete;
	const LineTable &operator=(const LineTable &) = delete;

	template <typename T>
	uint32_t FindLineEntryIndexByFileIndexImpl(
	uint32_t start_idx, T file_idx,
	const SourceLocationSpec &src_location_spec, LineEntry *line_entry_ptr,
	std::function<bool(T, uint16_t)> file_idx_matcher) {
	const size_t count = m_entries.size();
	size_t best_match = UINT32_MAX;

	if (!line_entry_ptr)
	return best_match;

	const uint32_t line = src_location_spec.GetLine().getValueOr(0);
	const uint16_t column =
	src_location_spec.GetColumn().getValueOr(LLDB_INVALID_COLUMN_NUMBER);
	const bool exact_match = src_location_spec.GetExactMatch();

	for (size_t idx = start_idx; idx < count; ++idx) {
	// Skip line table rows that terminate the previous row (is_terminal_entry
	// is non-zero)
	if (m_entries[idx].is_terminal_entry)
	continue;

	if (!file_idx_matcher(file_idx, m_entries[idx].file_idx))
	continue;

	// Exact match always wins. Otherwise try to find the closest line > the
	// desired line.
	// FIXME: Maybe want to find the line closest before and the line closest
	// after and if they're not in the same function, don't return a match.

	if (column == LLDB_INVALID_COLUMN_NUMBER) {
	if (m_entries[idx].line < line) {
	continue;
	} else if (m_entries[idx].line == line) {
	ConvertEntryAtIndexToLineEntry(idx, *line_entry_ptr);
	return idx;
	} else if (!exact_match) {
	if (best_match == UINT32_MAX \|\|
	m_entries[idx].line < m_entries[best_match].line)
	best_match = idx;
	}
	} else {
	if (m_entries[idx].line < line) {
	continue;
	} else if (m_entries[idx].line == line &&
	m_entries[idx].column == column) {
	ConvertEntryAtIndexToLineEntry(idx, *line_entry_ptr);
	return idx;
	} else if (!exact_match) {
	if (best_match == UINT32_MAX)
	best_match = idx;
	else if (m_entries[idx].line < m_entries[best_match].line)
	best_match = idx;
	else if (m_entries[idx].line == m_entries[best_match].line)
	if (m_entries[idx].column &&
	m_entries[idx].column < m_entries[best_match].column)
	best_match = idx;
	}
	}
	}

	if (best_match != UINT32_MAX) {
	if (line_entry_ptr)
	ConvertEntryAtIndexToLineEntry(best_match, *line_entry_ptr);
	return best_match;
	}
	return UINT32_MAX;
	}
	};

	} // namespace lldb_private

	#endif // LLDB_SYMBOL_LINETABLE_H