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‎.clang-format

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.cppsm/.clang-format

‎.cppsm

Submodule .cppsm added at ea2cd9a

‎.gitignore

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.cppsm/.gitignore

‎.gitmodules

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[submodule ".cppsm"]
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path = .cppsm
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url = https://github.com/cppsm/cppsm-boilerplate.git
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branch = master
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[submodule "requires/polyfill.cpp/v1"]
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path = requires/polyfill.cpp/v1
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url = https://github.com/per-framework/polyfill.cpp.git
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branch = v1
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[submodule "equipment/testing.cpp/v1"]
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path = equipment/testing.cpp/v1
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url = https://github.com/per-framework/testing.cpp.git
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branch = v1
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[submodule "requires/intrinsics.cpp/v1"]
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path = requires/intrinsics.cpp/v1
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url = https://github.com/per-framework/intrinsics.cpp.git
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branch = v1
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[submodule "requires/dumpster.cpp/v1"]
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path = requires/dumpster.cpp/v1
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url = https://github.com/per-framework/dumpster.cpp.git
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branch = v1
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[submodule "requires/lax.cpp/v1"]
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path = requires/lax.cpp/v1
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url = https://github.com/per-framework/lax.cpp.git
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branch = v1

‎.prettierrc

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.cppsm/.prettierrc

‎.travis.yml

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language: cpp
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notifications:
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email: false
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matrix:
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include:
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- os: linux
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dist: trusty
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addons:
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apt:
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sources:
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- ubuntu-toolchain-r-test
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- llvm-toolchain-trusty-7
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packages:
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- g++-8
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- clang-7
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- os: osx
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osx_image: xcode10.2
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- os: windows
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git:
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submodules: false
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before_install:
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- git submodule update --init
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script:
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- .cppsm/travis-ci || ./test

‎CMakeLists.txt

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cmake_minimum_required(VERSION 3.9)
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include(.cppsm/c++17-no-rtti-no-exns.cmake)

‎LICENSE.md

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Copyright © 2019 Vesa Karvonen
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Permission is hereby granted, free of charge, to any person obtaining a copy of
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this software and associated documentation files (the "Software"), to deal in
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the Software without restriction, including without limitation the rights to
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use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
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the Software, and to permit persons to whom the Software is furnished to do so,
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subject to the following conditions:
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The above copyright notice and this permission notice shall be included in all
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copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
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FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
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COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
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IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

‎README.md

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# [≡](#contents) [RDCSS.C++](#) [![Build Status](https://travis-ci.org/per-framework/rdcss.cpp.svg?branch=v1)](https://travis-ci.org/per-framework/rdcss.cpp)
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[RDCSS](https://www.cl.cam.ac.uk/research/srg/netos/papers/2002-casn.pdf) based
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multi-word compare-and-swap for C++.
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## <a id="contents"></a> [≡](#contents) [Contents](#contents)
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- [References](#references)
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## <a id="references"></a> [≡](#contents) [References](#references)
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- [A Practical Multi-Word Compare-and-Swap Operation](https://www.cl.cam.ac.uk/research/srg/netos/papers/2002-casn.pdf)
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- [Lock-Free Linked Lists Using Compare-and-Swap](http://people.csail.mit.edu/bushl2/rpi/portfolio/lockfree-grape/documents/lock-free-linked-lists.pdf)
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- [Easy Lock-Free Indexing in Non-Volatile Memory](http://justinlevandoski.org/papers/mwcas.pdf)
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- [Persistent Multi-Word Compare-and-Swap (PMwCAS) for NVRAM](https://github.com/Microsoft/pmwcas)
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- [A Practical Wait-Free Multi-Word Compare-and-Swap Operation](https://www.osti.gov/servlets/purl/1110662)
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- [Algorithms for Scalable Synchronization on Shared-Memory Multiprocessors](http://web.mit.edu/6.173/www/currentsemester/readings/R06-scalable-synchronization-1991.pdf)
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- [Reagents: expressing and composing fine-grained concurrency](http://aturon.github.io/academic/reagents.pdf)
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- [`std::atomic`](https://en.cppreference.com/w/cpp/atomic/atomic)

‎equipment/testing.cpp/v1

Submodule v1 added at 7aeb198

‎internals/CMakeLists.txt

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add_conventional_executable_test(rdcss_test)
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target_link_libraries(rdcss_test PRIVATE rdcss_v1 testing_v1)

‎internals/testing/test.cpp

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#include "rdcss_v1/casn.hpp"
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#include "testing_v1/test.hpp"
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using namespace testing_v1;
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auto test_casn = test([]() {
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using namespace rdcss_v1;
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auto i = CASN::atom(101);
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auto b = CASN::atom(false);
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CASN::store(b, true);
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verify(CASN::load(i) == 101);
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verify(CASN::load(b) == true);
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verify(!CASN::casn(CASN::op(i, 101, 69), CASN::op(b, false, true)));
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verify(CASN::load(i) == 101);
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verify(CASN::load(b) == true);
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verify(CASN::casn(CASN::op(i, 101, 69), CASN::op(b, true, false)));
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verify(CASN::load(i) == 69);
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verify(CASN::load(b) == false);
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});

‎provides/CMakeLists.txt

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add_conventional_library(rdcss_v1)
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target_link_libraries(rdcss_v1 PUBLIC dumpster_v1 polyfill_v1 lax_v1 PRIVATE intrinsics_v1)

‎provides/include/rdcss_v1/casn.hpp

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#pragma once
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#include "rdcss_v1/casn_synopsis.hpp"
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#include "rdcss_v1/config.hpp"
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#include "lax_v1/comparison.hpp"
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#include "lax_v1/logical.hpp"
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#include "lax_v1/type_traits.hpp"
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#include <atomic>
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#include <cstdint>
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#include <type_traits>
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#include <utility>
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namespace rdcss_v1 {
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class CASN_private : CASN {
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friend struct CASN;
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template <class Value>
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struct is_stored_plain_m
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: lax::or_m<
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lax::and_m<
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lax::is_pointer_m<Value>,
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lax::lte_m<lax::value_t<size_t, 2>,
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lax::alignment_of_m<lax::remove_pointer_m<Value>>>>,
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lax::and_m<lax::is_array_m<Value>,
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is_stored_plain_m<lax::remove_all_extents_m<Value>>>> {};
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template <class Value>
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static inline constexpr bool is_stored_plain_v =
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lax::value_of_v<is_stored_plain_m<lax::type_t<Value>>>;
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static_assert(!is_stored_plain_v<int>);
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static_assert(is_stored_plain_v<int *>);
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static_assert(is_stored_plain_v<int * [2]>);
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static_assert(is_stored_plain_v<float * [2]>);
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static_assert(!is_stored_plain_v<float>);
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static inline constexpr size_t align_to(size_t alignment, size_t size) {
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return (size + alignment - 1) & ~(alignment - 1);
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}
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using elem_t = std::atomic<void *>;
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template <class Value>
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static inline constexpr size_t num_elems_for =
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align_to(sizeof(elem_t),
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sizeof(Value) * (is_stored_plain_v<Value> ? 1 : 2)) /
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sizeof(elem_t);
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template <class Value> struct atom_t {
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private:
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elem_t elems[num_elems_for<Value>];
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};
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};
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class CASN_detail : CASN {
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friend struct CASN;
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struct atom_base_t;
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struct content_t;
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enum type_t : int_fast8_t;
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template <class Value> struct value_t;
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enum status_t : int_fast8_t;
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struct rdcss_t;
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struct casn_t;
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static content_t *cas1(atom_base_t &atom, content_t *expected,
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content_t *desired);
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static bool is_rdcss(content_t *content);
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static content_t *rdcss(rdcss_t &descriptor);
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static void rdcss_complete(atom_base_t &atom, rdcss_t &descriptor);
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static content_t *rdcss_read(atom_base_t &atom);
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static bool is_casn(content_t *content);
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static bool casn(casn_t &descriptor);
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static content_t *casn_read(atom_base_t &atom);
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};
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} // namespace rdcss_v1
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struct rdcss_v1::CASN_detail::atom_base_t {
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std::atomic<content_t *> content;
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};
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//
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enum rdcss_v1::CASN_detail::type_t : int_fast8_t { RDCSS = -1, VALUE, CASN };
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struct rdcss_v1::CASN_detail::content_t {
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type_t type;
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};
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enum rdcss_v1::CASN_detail::status_t : int_fast8_t {
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FAILED = -1,
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UNDECIDED,
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SUCCEEDED
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};
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struct rdcss_v1::CASN_detail::rdcss_t : content_t {
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std::atomic<status_t> &status; // UNDECIDED expected
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atom_base_t &atom;
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content_t *expected;
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content_t *desired;
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};
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struct rdcss_v1::CASN_detail::casn_t : content_t {
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std::atomic<status_t> status;
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op_mono_t *ops;
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};
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struct rdcss_v1::CASN::op_mono_t {
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CASN_detail::atom_base_t *atom;
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CASN_detail::content_t *before;
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CASN_detail::content_t *after;
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};
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template <class Value> struct rdcss_v1::CASN_detail::value_t : content_t {
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value_t(Value &&value) : content_t{VALUE}, value(std::move(value)) {}
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value_t(const Value &value) : content_t{VALUE}, value(value) {}
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// TODO ref count?
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Value value;
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};
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//
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template <class Value>
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struct rdcss_v1::CASN::atom_t : CASN_detail::atom_base_t {};
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template <class Value>
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rdcss_v1::CASN::atom_t<std::remove_cvref_t<Value>>
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rdcss_v1::CASN::atom(Value &&value) {
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return {{new CASN_detail::value_t<std::remove_cvref_t<Value>>(
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std::forward<Value>(value))}};
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}
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template <class Value> Value rdcss_v1::CASN::load(const atom_t<Value> &atom) {
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CASN_detail::content_t *result =
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CASN_detail::casn_read(const_cast<atom_t<Value> &>(atom));
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return static_cast<CASN_detail::value_t<Value> *>(result)->value;
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}
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template <class Value, class Forwardable_Value>
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void rdcss_v1::CASN::store(atom_t<Value> &atom, Forwardable_Value &&value) {
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CASN_detail::value_t<Value> *desired =
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new CASN_detail::value_t<Value>(std::forward<Forwardable_Value>(value));
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while (true) {
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CASN_detail::content_t *expected = CASN_detail::casn_read(atom);
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if (expected == CASN_detail::cas1(atom, expected, desired))
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break;
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}
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}
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//
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template <class Value> struct rdcss_v1::CASN::op_t : op_mono_t {};
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template <class Value, class Forwardable_Expected, class Forwardable_Desired>
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rdcss_v1::CASN::op_t<Value> rdcss_v1::CASN::op(atom_t<Value> &atom,
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Forwardable_Expected &&expected,
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Forwardable_Desired &&desired) {
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CASN_detail::content_t *before = CASN_detail::casn_read(atom);
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CASN_detail::content_t *after = nullptr;
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if (expected == static_cast<CASN_detail::value_t<Value> *>(before)->value) {
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after = new CASN_detail::value_t<Value>(
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std::forward<Forwardable_Desired>(desired));
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} else {
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before = nullptr;
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}
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return {op_mono_t{&atom, before, after}};
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}
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template <class Value>
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rdcss_v1::CASN::op_mono_t rdcss_v1::CASN::as_mono(op_t<Value> &op) {
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return op;
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}
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template <class... Ops> bool rdcss_v1::CASN::casn(Ops &&... ops) {
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op_mono_t mono_ops[] = {std::forward<Ops>(ops)...,
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{nullptr, nullptr, nullptr}};
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return casn(mono_ops);
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}

‎provides/include/rdcss_v1/casn_synopsis.hpp

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#pragma once
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#include "polyfill_v1/type_traits.hpp"
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namespace rdcss_v1 {
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// Multi-word atomic compare and set (CASN)
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struct CASN {
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// Mutable atoms -------------------------------------------------------------
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template <class Value> struct atom_t;
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// A mutable atom that supports CASN operations.
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template <class Value>
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static atom_t<std::remove_cvref_t<Value>> atom(Value &&value);
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// Creates a mutable atom.
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template <class Value> static Value load(const atom_t<Value> &atom);
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// Atomically loads and returns the current value of the atom.
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template <class Value, class Forwardable_Value>
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static void store(atom_t<Value> &atom, Forwardable_Value &&desired);
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// Atomically replaces the value of the atom with the desired value.
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// Typed CASN ----------------------------------------------------------------
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template <class Value> struct op_t;
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// Describes a single CAS operation.
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template <class Value, class Forwardable_Expected, class Forwardable_Desired>
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static op_t<Value> op(atom_t<Value> &atom, Forwardable_Expected &&expected,
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Forwardable_Desired &&desired);
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// Specifies a single CAS operation.
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template <class... Ops> static bool casn(Ops &&... ops);
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// Attempts the described CAS operations. Returns `true` on success and
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// `false` on failure.
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// Unityped CASN -------------------------------------------------------------
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struct op_mono_t;
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// Describes a single CAS operation in a unityped manner.
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template <class Value> static op_mono_t as_mono(op_t<Value> &op);
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// Creates a unityped reference to the CAS operation.
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static bool casn(op_mono_t *mono_ops);
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// Attempts the described unityped CAS operations. Returns `true` on success
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// and `false` on failure.
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};
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} // namespace rdcss_v1

‎provides/include/rdcss_v1/config.hpp

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#pragma once
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#include "lax_v1/config.hpp"
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namespace rdcss_v1 {
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namespace lax = lax_v1;
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}

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