implemented SPIR-V shader export

AssetStudioUtility/CSspv/Reader.cs

@@ -0,0 +1,50 @@
+using System;
+using System.IO;
+using System.Runtime.CompilerServices;
+
+namespace SpirV
+{
+	internal sealed class Reader
+	{
+		public Reader(BinaryReader reader)
+		{
+			reader_ = reader;
+			uint magicNumber = reader_.ReadUInt32();
+			if (magicNumber == Meta.MagicNumber)
+			{
+				littleEndian_ = true;
+			}
+			else if (Reverse(magicNumber) == Meta.MagicNumber)
+			{
+				littleEndian_ = false;
+			}
+			else
+			{
+				throw new Exception("Invalid magic number");
+			}
+		}
+
+		public uint ReadDWord()
+		{
+			if (littleEndian_)
+			{
+				return reader_.ReadUInt32 ();
+			}
+			else
+			{
+				return Reverse(reader_.ReadUInt32());
+			}
+		}
+
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		private static uint Reverse(uint u)
+		{
+			return (u << 24) | (u & 0xFF00U) << 8 | (u >> 8) & 0xFF00U | (u >> 24);
+		}
+
+		public bool EndOfStream => reader_.BaseStream.Position == reader_.BaseStream.Length;
+
+		private readonly BinaryReader reader_;
+		private readonly bool littleEndian_;
+	}
+}