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Diffstat (limited to '3rdParty/Boost/src/boost/uuid/detail/uuid_x86.hpp')
-rw-r--r--3rdParty/Boost/src/boost/uuid/detail/uuid_x86.hpp109
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diff --git a/3rdParty/Boost/src/boost/uuid/detail/uuid_x86.hpp b/3rdParty/Boost/src/boost/uuid/detail/uuid_x86.hpp
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+++ b/3rdParty/Boost/src/boost/uuid/detail/uuid_x86.hpp
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+/*
+ * Copyright Andrey Semashev 2013.
+ * Distributed under the Boost Software License, Version 1.0.
+ * (See accompanying file LICENSE_1_0.txt or copy at
+ * http://www.boost.org/LICENSE_1_0.txt)
+ */
+/*!
+ * \file uuid/detail/uuid_x86.hpp
+ *
+ * \brief This header contains optimized SSE implementation of \c boost::uuid operations.
+ */
+
+#ifndef BOOST_UUID_DETAIL_UUID_X86_HPP_INCLUDED_
+#define BOOST_UUID_DETAIL_UUID_X86_HPP_INCLUDED_
+
+// MSVC does not always have immintrin.h (at least, not up to MSVC 10), so include the appropriate header for each instruction set
+#if defined(BOOST_UUID_USE_SSE41)
+#include <smmintrin.h>
+#elif defined(BOOST_UUID_USE_SSE3)
+#include <pmmintrin.h>
+#else
+#include <emmintrin.h>
+#endif
+
+namespace boost {
+namespace uuids {
+namespace detail {
+
+BOOST_FORCEINLINE __m128i load_unaligned_si128(const uint8_t* p) BOOST_NOEXCEPT
+{
+#if defined(BOOST_UUID_USE_SSE3)
+ return _mm_lddqu_si128(reinterpret_cast< const __m128i* >(p));
+#else
+ return _mm_loadu_si128(reinterpret_cast< const __m128i* >(p));
+#endif
+}
+
+} // namespace detail
+
+inline bool uuid::is_nil() const BOOST_NOEXCEPT
+{
+ register __m128i mm = uuids::detail::load_unaligned_si128(data);
+#if defined(BOOST_UUID_USE_SSE41)
+ return _mm_test_all_zeros(mm, mm) != 0;
+#else
+ mm = _mm_cmpeq_epi8(mm, _mm_setzero_si128());
+ return _mm_movemask_epi8(mm) == 0xFFFF;
+#endif
+}
+
+inline void uuid::swap(uuid& rhs) BOOST_NOEXCEPT
+{
+ register __m128i mm_this = uuids::detail::load_unaligned_si128(data);
+ register __m128i mm_rhs = uuids::detail::load_unaligned_si128(rhs.data);
+ _mm_storeu_si128(reinterpret_cast< __m128i* >(rhs.data), mm_this);
+ _mm_storeu_si128(reinterpret_cast< __m128i* >(data), mm_rhs);
+}
+
+inline bool operator== (uuid const& lhs, uuid const& rhs) BOOST_NOEXCEPT
+{
+ register __m128i mm_left = uuids::detail::load_unaligned_si128(lhs.data);
+ register __m128i mm_right = uuids::detail::load_unaligned_si128(rhs.data);
+
+ register __m128i mm_cmp = _mm_cmpeq_epi32(mm_left, mm_right);
+#if defined(BOOST_UUID_USE_SSE41)
+ return _mm_test_all_ones(mm_cmp);
+#else
+ return _mm_movemask_epi8(mm_cmp) == 0xFFFF;
+#endif
+}
+
+inline bool operator< (uuid const& lhs, uuid const& rhs) BOOST_NOEXCEPT
+{
+ register __m128i mm_left = uuids::detail::load_unaligned_si128(lhs.data);
+ register __m128i mm_right = uuids::detail::load_unaligned_si128(rhs.data);
+
+ // To emulate lexicographical_compare behavior we have to perform two comparisons - the forward and reverse one.
+ // Then we know which bytes are equivalent and which ones are different, and for those different the comparison results
+ // will be opposite. Then we'll be able to find the first differing comparison result (for both forward and reverse ways),
+ // and depending on which way it is for, this will be the result of the operation. There are a few notes to consider:
+ //
+ // 1. Due to little endian byte order the first bytes go into the lower part of the xmm registers,
+ // so the comparison results in the least significant bits will actually be the most signigicant for the final operation result.
+ // This means we have to determine which of the comparison results have the least significant bit on, and this is achieved with
+ // the "(x - 1) ^ x" trick.
+ // 2. Because there is only signed comparison in SSE/AVX, we have to invert byte comparison results whenever signs of the corresponding
+ // bytes are different. I.e. in signed comparison it's -1 < 1, but in unsigned it is the opposite (255 > 1). To do that we XOR left and right,
+ // making the most significant bit of each byte 1 if the signs are different, and later apply this mask with another XOR to the comparison results.
+ // 3. pcmpgtw compares for "greater" relation, so we swap the arguments to get what we need.
+
+ const __m128i mm_signs_mask = _mm_xor_si128(mm_left, mm_right);
+
+ __m128i mm_cmp = _mm_cmpgt_epi8(mm_right, mm_left), mm_rcmp = _mm_cmpgt_epi8(mm_left, mm_right);
+
+ mm_cmp = _mm_xor_si128(mm_signs_mask, mm_cmp);
+ mm_rcmp = _mm_xor_si128(mm_signs_mask, mm_rcmp);
+
+ uint32_t cmp = static_cast< uint32_t >(_mm_movemask_epi8(mm_cmp)), rcmp = static_cast< uint32_t >(_mm_movemask_epi8(mm_rcmp));
+
+ cmp = (cmp - 1u) ^ cmp;
+ rcmp = (rcmp - 1u) ^ rcmp;
+
+ return static_cast< uint16_t >(cmp) < static_cast< uint16_t >(rcmp);
+}
+
+} // namespace uuids
+} // namespace boost
+
+#endif // BOOST_UUID_DETAIL_UUID_X86_HPP_INCLUDED_