Fix counting the DwarfLineProgramTable layout (#23)

Author: filipnavara

src/LibObjectFile/Dwarf/DwarfLineProgramTable.cs

@@ -682,7 +682,7 @@ protected override void UpdateLayout(DwarfLayoutContext layoutContext)
             ulong sizeOf = 0;
 
             // unit_length
-            sizeOf += DwarfHelper.SizeOfUInt(Is64BitEncoding);
+            sizeOf += DwarfHelper.SizeOfUnitLength(Is64BitEncoding);
 
             sizeOf += 2; // version (uhalf)
 
@@ -691,18 +691,26 @@ protected override void UpdateLayout(DwarfLayoutContext layoutContext)
             ulong headerLengthStart = sizeOf;
 
             // minimum_instruction_length
+            sizeOf++;
+
+            if (Version >= 4)
+            {
+                // maximum_operations_per_instruction
+                sizeOf++;
+            }
+
             // default_is_stmt
             // line_base
             // line_range
             // opcode_base
-            sizeOf += 5;
+            sizeOf += 4;
 
             // StandardOpCodeLengths
             foreach (var opcodeLength in _standardOpCodeLengths)
             {
                 sizeOf += DwarfHelper.SizeOfULEB128(opcodeLength);
             }
-            
+
             // Write directory names
             _directoryNameToIndex.Clear();
             _directoryNames.Clear();
@@ -738,8 +746,8 @@ private void RecordDirectory(string directoryName, ref ulong sizeOf, out uint di
         {
             if (!_directoryNameToIndex.TryGetValue(directoryName, out dirIndex))
             {
-                uint directoryIndex = (uint) _directoryNames.Count + 1;
-                _directoryNameToIndex.Add(directoryName, directoryIndex);
+                dirIndex = (uint) _directoryNames.Count + 1;
+                _directoryNameToIndex.Add(directoryName, dirIndex);
                 sizeOf += (ulong) Encoding.UTF8.GetByteCount(directoryName) + 1;
                 _directoryNames.Add(directoryName);
             }
@@ -1365,4 +1373,4 @@ public override string ToString()
             return $"Section .debug_line, {nameof(Version)}: {Version}, {nameof(Is64BitEncoding)}: {Is64BitEncoding}, {nameof(FileNames)}: {FileNames.Count}, {nameof(LineSequences)}: {LineSequences.Count}";
         }
     }
-}
+}