protected DwarfMethodSource GetMethodSource(DieSubprogram subprog, int start_row, int end_row) { DwarfMethodSource source; source = (DwarfMethodSource) method_source_hash [subprog.Offset]; if (source != null) return source; source = new DwarfMethodSource (subprog, start_row, end_row); method_source_hash.Add (subprog.Offset, source); return source; }