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

#include "DIERef.h"
#include "DWARFCompileUnit.h"
#include "DWARFFormValue.h"
#include "DWARFDebugInfo.h"
#include "SymbolFileDWARF.h"
#include "SymbolFileDWARFDebugMap.h"

DIERef::DIERef() :
    cu_offset(DW_INVALID_OFFSET),
    die_offset(DW_INVALID_OFFSET)
{}

DIERef::DIERef(dw_offset_t c, dw_offset_t d) :
    cu_offset(c),
    die_offset(d)
{}

DIERef::DIERef(lldb::user_id_t uid, SymbolFileDWARF *dwarf) :
    cu_offset(DW_INVALID_OFFSET),
    die_offset(uid&0xffffffff)
{
    SymbolFileDWARFDebugMap *debug_map = dwarf->GetDebugMapSymfile();
    if (debug_map)
    {
        const uint32_t oso_idx = debug_map->GetOSOIndexFromUserID(uid);
        SymbolFileDWARF *actual_dwarf = debug_map->GetSymbolFileByOSOIndex(oso_idx);
        if (actual_dwarf)
        {
            DWARFDebugInfo *debug_info = actual_dwarf->DebugInfo();
            if (debug_info)
            {
                DWARFCompileUnit *dwarf_cu = debug_info->GetCompileUnitContainingDIEOffset(die_offset);
                if (dwarf_cu)
                {
                    cu_offset = dwarf_cu->GetOffset();
                    return;
                }
            }
        }
        die_offset = DW_INVALID_OFFSET;
    }
    else
    {
        cu_offset = uid>>32;
    }
}

DIERef::DIERef(const DWARFFormValue& form_value) :
    cu_offset(DW_INVALID_OFFSET),
    die_offset(DW_INVALID_OFFSET)
{
    if (form_value.IsValid())
    {
        const DWARFCompileUnit* dwarf_cu = form_value.GetCompileUnit();
        if (dwarf_cu)
        {
            if (dwarf_cu->GetBaseObjOffset() != DW_INVALID_OFFSET)
                cu_offset = dwarf_cu->GetBaseObjOffset();
            else
                cu_offset = dwarf_cu->GetOffset();
        }
        die_offset = form_value.Reference();
    }
}

lldb::user_id_t
DIERef::GetUID(SymbolFileDWARF *dwarf) const
{
    //----------------------------------------------------------------------
    // Each SymbolFileDWARF will set its ID to what is expected.
    //
    // SymbolFileDWARF, when used for DWARF with .o files on MacOSX, has the
    // ID set to the compile unit index.
    //
    // SymbolFileDWARFDwo sets the ID to the compile unit offset.
    //----------------------------------------------------------------------
    if (dwarf)
        return dwarf->GetID() | die_offset;
    else
        return LLDB_INVALID_UID;
}