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engines/sci/engine/gc.h

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+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * 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, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+
+#ifndef SCI_ENGINE_GC_H
+#define SCI_ENGINE_GC_H
+
+#include "common/hashmap.h"
+#include "sci/engine/vm_types.h"
+#include "sci/engine/state.h"
+
+namespace Sci {
+
+struct reg_t_Hash {
+	uint operator()(const reg_t& x) const {
+		return (x.getSegment() << 3) ^ x.getOffset() ^ (x.getOffset() << 16);
+	}
+};
+
+/*
+ * The AddrSet is a "set" of reg_t values.
+ * We don't have a HashSet type, so we abuse a HashMap for this.
+ */
+typedef Common::HashMap<reg_t, bool, reg_t_Hash> AddrSet;
+
+/**
+ * Finds all used references and normalises them to their memory addresses
+ * @param s The state to gather all information from
+ * @return A hash map containing entries for all used references
+ */
+AddrSet *findAllActiveReferences(EngineState *s);
+
+/**
+ * Runs garbage collection on the current system state
+ * @param s The state in which we should gc
+ */
+void run_gc(EngineState *s);
+
+struct WorklistManager {
+	Common::Array<reg_t> _worklist;
+	AddrSet _map;	// used for 2 contains() calls, inside push() and run_gc()
+
+	void push(reg_t reg);
+	void pushArray(const Common::Array<reg_t> &tmp);
+};
+
+
+} // End of namespace Sci
+
+#endif // SCI_ENGINE_GC_H