Reorganizing source code. Created util dir

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

src/util/page.h

@@ -0,0 +1,42 @@
+/*++
+Copyright (c) 2006 Microsoft Corporation
+
+Module Name:
+
+    page.h
+
+Abstract:
+
+    Goodies for manipulating pages of memory.
+
+Author:
+
+    Leonardo de Moura (leonardo) 2011-02-27.
+
+Revision History:
+
+--*/
+#ifndef _PAGE_H_
+#define _PAGE_H_
+
+#include"memory_manager.h"
+
+#define PAGE_HEADER_SZ sizeof(size_t)
+#define DEFAULT_PAGE_SIZE (8192 - PAGE_HEADER_SZ)
+#define PAGE_HEADER_MASK (static_cast<size_t>(-1) - 1)
+
+inline char * prev_page(char * page) {
+    size_t tagged_ptr = reinterpret_cast<size_t *>(page)[-1];
+    return reinterpret_cast<char *>(tagged_ptr & PAGE_HEADER_MASK);
+}
+inline bool is_default_page(char * page) {
+    size_t tagged_ptr = reinterpret_cast<size_t *>(page)[-1];
+    return static_cast<bool>(tagged_ptr & 1);
+}
+inline char * end_of_default_page(char * p) { return p + DEFAULT_PAGE_SIZE; }
+void del_pages(char * page);
+char * allocate_default_page(char * prev, char * & free_pages);
+char * allocate_page(char * prev, size_t sz);
+void recycle_page(char * p, char * & free_pages);
+
+#endif