xref: /freebsd-11-stable/contrib/llvm-project/lldb/include/lldb/Symbol/UnwindTable.h

//===-- Symtab.h ------------------------------------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//


#ifndef liblldb_UnwindTable_h
#define liblldb_UnwindTable_h

#include <map>
#include <mutex>

#include "lldb/lldb-private.h"

namespace lldb_private {

// A class which holds all the FuncUnwinders objects for a given ObjectFile.
// The UnwindTable is populated with FuncUnwinders objects lazily during
// the debug session.

class UnwindTable
{
public:
    UnwindTable(ObjectFile& objfile);
    ~UnwindTable();

    lldb_private::DWARFCallFrameInfo *
    GetEHFrameInfo ();

    lldb_private::CompactUnwindInfo *
    GetCompactUnwindInfo ();

    ArmUnwindInfo *
    GetArmUnwindInfo ();

    lldb::FuncUnwindersSP
    GetFuncUnwindersContainingAddress (const Address& addr, SymbolContext &sc);

    bool
    GetAllowAssemblyEmulationUnwindPlans ();

// Normally when we create a new FuncUnwinders object we track it in this UnwindTable so it can
// be reused later.  But for the target modules show-unwind we want to create brand new
// UnwindPlans for the function of interest - so ignore any existing FuncUnwinders for that
// function and don't add this new one to our UnwindTable.
// This FuncUnwinders object does have a reference to the UnwindTable but the lifetime of this
// uncached FuncUnwinders is expected to be short so in practice this will not be a problem.
    lldb::FuncUnwindersSP
    GetUncachedFuncUnwindersContainingAddress (const Address& addr, SymbolContext &sc);

    bool
    GetArchitecture (lldb_private::ArchSpec &arch);

private:
    void
    Dump (Stream &s);

    void Initialize ();

    typedef std::map<lldb::addr_t, lldb::FuncUnwindersSP> collection;
    typedef collection::iterator iterator;
    typedef collection::const_iterator const_iterator;

    ObjectFile&         m_object_file;
    collection          m_unwinds;

    bool                m_initialized;  // delay some initialization until ObjectFile is set up
    std::mutex m_mutex;

    std::unique_ptr<DWARFCallFrameInfo> m_eh_frame_up;
    std::unique_ptr<CompactUnwindInfo>  m_compact_unwind_up;
    std::unique_ptr<ArmUnwindInfo>      m_arm_unwind_up;

    DISALLOW_COPY_AND_ASSIGN (UnwindTable);
};

} // namespace lldb_private

#endif  // liblldb_UnwindTable_h