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/*
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* Copyright (c) 2000, 2003, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation. Oracle designates this
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* particular file as subject to the "Classpath" exception as provided
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* by Oracle in the LICENSE file that accompanied this code.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*/
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#include "mlib_image.h"
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/***************************************************************/
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typedef union {
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mlib_d64 db;
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struct {
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#ifdef _LITTLE_ENDIAN
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mlib_s32 int1, int0;
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#else
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mlib_s32 int0, int1;
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#endif
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} two_int;
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} type_union_mlib_d64;
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#define DVAIN52 4.503599627370496e15
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/***************************************************************/
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mlib_s32 mlib_ilogb(mlib_d64 X)
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{
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type_union_mlib_d64 arg;
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mlib_s32 n;
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if (X == 0.0)
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return -MLIB_S32_MAX;
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arg.db = X;
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n = arg.two_int.int0 & 0x7ff00000;
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if (n)
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n = (n < 0x7ff00000) ? (n >> 20) - 1023 : MLIB_S32_MAX;
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else {
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arg.db = X * DVAIN52;
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n = ((arg.two_int.int0 & 0x7ff00000) >> 20) - 1075;
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}
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return n;
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}
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/***************************************************************/
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