From 267c6f2ac71f92999e969232431ba04678e7437e Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 15 Apr 2024 07:54:39 +0200 Subject: Adding upstream version 4:24.2.0. Signed-off-by: Daniel Baumann --- include/o3tl/hash_combine.hxx | 55 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 include/o3tl/hash_combine.hxx (limited to 'include/o3tl/hash_combine.hxx') diff --git a/include/o3tl/hash_combine.hxx b/include/o3tl/hash_combine.hxx new file mode 100644 index 0000000000..48e1426222 --- /dev/null +++ b/include/o3tl/hash_combine.hxx @@ -0,0 +1,55 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * This file is part of the LibreOffice project. + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. + */ + +#pragma once + +#include +#include +#include + +namespace o3tl +{ +template +inline std::enable_if_t<(sizeof(N) == 4)> hash_combine(N& nSeed, T const* pValue, size_t nCount) +{ + static_assert(sizeof(nSeed) == 4); + for (size_t i = 0; i < nCount; ++i) + { + nSeed ^= std::hash{}(*pValue) + 0x9E3779B9u + (nSeed << 6) + (nSeed >> 2); + ++pValue; + } +} + +template +inline std::enable_if_t<(sizeof(N) == 4)> hash_combine(N& nSeed, T const& nValue) +{ + static_assert(sizeof(nSeed) == 4); + nSeed ^= std::hash{}(nValue) + 0x9E3779B9u + (nSeed << 6) + (nSeed >> 2); +} + +template +inline std::enable_if_t<(sizeof(N) == 8)> hash_combine(N& nSeed, T const* pValue, size_t nCount) +{ + static_assert(sizeof(nSeed) == 8); + for (size_t i = 0; i < nCount; ++i) + { + nSeed ^= std::hash{}(*pValue) + 0x9E3779B97F4A7C15llu + (nSeed << 12) + (nSeed >> 4); + ++pValue; + } +} + +template +inline std::enable_if_t<(sizeof(N) == 8)> hash_combine(N& nSeed, T const& nValue) +{ + static_assert(sizeof(nSeed) == 8); + nSeed ^= std::hash{}(nValue) + 0x9E3779B97F4A7C15llu + (nSeed << 12) + (nSeed >> 4); +} +} + +/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */ -- cgit v1.2.3