Shader Disk Cache implementation for D3D. Saves generated shaders on disk. Eliminates "freeze jerks" in D3D plugin the _second_ and later times you play something.... not much to do about the first time. The D3D shader compiler is just slow.

Also assorted cleanup around the shader code.

git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@4869 8ced0084-cf51-0410-be5f-012b33b47a6e

Source/Core/Common/Src/LinearDiskCache.h

@@ -0,0 +1,67 @@
+// Copyright (C) 2003 Dolphin Project.
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, version 2.0.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License 2.0 for more details.
+
+// A copy of the GPL 2.0 should have been included with the program.
+// If not, see http://www.gnu.org/licenses/
+
+// Official SVN repository and contact information can be found at
+// http://code.google.com/p/dolphin-emu/
+
+#ifndef _LINEAR_DISKCACHE
+#define _LINEAR_DISKCACHE
+
+#include "Common.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+
+// On disk format:
+// uint32 'DCAC'
+// uint32 version;  // svn_rev
+// uint32 key_length;
+// uint32 value_length;
+// ....   key;
+// ....   value;
+
+class LinearDiskCacheReader {
+public:
+	virtual void Read(const u8 *key, int key_size, const u8 *value, int value_size) = 0;
+};
+
+// Dead simple unsorted key-value store with append functionality.
+// No random read functionality, all reading is done in OpenAndRead.
+// Keys and values can contain any characters, including \0.
+//
+// Suitable for caching generated shader bytecode between executions.
+// Not tuned for extreme performance but should be reasonably fast.
+// Does not support keys or values larger than 2GB, which should be reasonable.
+// Keys must have non-zero length; values can have zero length.
+class LinearDiskCache {
+public:
+	LinearDiskCache();
+
+	// Returns the number of items read from the cache.
+	int OpenAndRead(const char *filename, LinearDiskCacheReader *reader);
+	void Close();
+	void Sync();
+
+	// Appends a key-value pair to the store.
+	void Append(const u8 *key, int key_size, const u8 *value, int value_size);
+
+private:
+	void WriteHeader();
+	bool ValidateHeader();
+
+	FILE *file_;
+	int num_entries_;
+};
+
+#endif  // _LINEAR_DISKCACHE