59 lines
2.1 KiB
C++
59 lines
2.1 KiB
C++
/*
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* Copyright (c) 2017, 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.
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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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*/
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#include "precompiled.hpp"
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#include "utilities/count_trailing_zeros.hpp"
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#include "utilities/globalDefinitions.hpp"
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#include "unittest.hpp"
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TEST(count_trailing_zeros, one_or_two_set_bits) {
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unsigned i = 0; // Position of a set bit.
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for (uintx ix = 1; ix != 0; ix <<= 1, ++i) {
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unsigned j = 0; // Position of a set bit.
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for (uintx jx = 1; jx != 0; jx <<= 1, ++j) {
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uintx value = ix | jx;
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EXPECT_EQ(MIN2(i, j), count_trailing_zeros(value))
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<< "value = " << value;
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}
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}
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}
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TEST(count_trailing_zeros, all_ones_followed_by_all_zeros) {
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unsigned i = BitsPerWord - 1; // Index of most significant set bit.
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uintx value = ~(uintx)0;
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for ( ; value != 0; value >>= 1, --i) {
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EXPECT_EQ(0u, count_trailing_zeros(value))
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<< "value = " << value;
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}
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}
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TEST(count_trailing_zeros, all_zeros_followed_by_all_ones) {
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unsigned i = 0; // Index of least significant set bit.
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uintx value = ~(uintx)0;
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for ( ; value != 0; value <<= 1, ++i) {
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EXPECT_EQ(i, count_trailing_zeros(value))
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<< "value = " << value;
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}
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}
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