| /* |
| Copyright Charly Chevalier 2015 |
| Copyright Joel Falcou 2015 |
| 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) |
| */ |
| |
| #include <boost/predef/hardware/simd/x86.h> |
| #include <boost/predef/hardware/simd/x86_amd.h> |
| #include <boost/predef/hardware/simd/arm.h> |
| #include <boost/predef/hardware/simd/ppc.h> |
| |
| #ifndef BOOST_PREDEF_HARDWARE_SIMD_H |
| #define BOOST_PREDEF_HARDWARE_SIMD_H |
| |
| #include <boost/predef/version_number.h> |
| |
| /* tag::reference[] |
| = Using the `BOOST_HW_SIMD_*` predefs |
| |
| SIMD predefs depend on compiler options. For example, you will have to add the |
| option `-msse3` to clang or gcc to enable SSE3. SIMD predefs are also inclusive. |
| This means that if SSE3 is enabled, then every other extensions with a lower |
| version number will implicitly be enabled and detected. However, some extensions |
| are CPU specific, they may not be detected nor enabled when an upper version is |
| enabled. |
| |
| NOTE: SSE(1) and SSE2 are automatically enabled by default when using x86-64 |
| architecture. |
| |
| To check if any SIMD extension has been enabled, you can use: |
| |
| [source] |
| ---- |
| #include <boost/predef/hardware/simd.h> |
| #include <iostream> |
| |
| int main() |
| { |
| #if defined(BOOST_HW_SIMD_AVAILABLE) |
| std::cout << "SIMD detected!" << std::endl; |
| #endif |
| return 0; |
| } |
| ---- |
| |
| When writing SIMD specific code, you may want to check if a particular extension |
| has been detected. To do so you have to use the right architecture predef and |
| compare it. Those predef are of the form `BOOST_HW_SIMD_"ARCH"` (where `"ARCH"` |
| is either `ARM`, `PPC`, or `X86`). For example, if you compile code for x86 |
| architecture, you will have to use `BOOST_HW_SIMD_X86`. Its value will be the |
| version number of the most recent SIMD extension detected for the architecture. |
| |
| To check if an extension has been enabled: |
| |
| [source] |
| ---- |
| #include <boost/predef/hardware/simd.h> |
| #include <iostream> |
| |
| int main() |
| { |
| #if BOOST_HW_SIMD_X86 >= BOOST_HW_SIMD_X86_SSE3_VERSION |
| std::cout << "This is SSE3!" << std::endl; |
| #endif |
| return 0; |
| } |
| ---- |
| |
| NOTE: The *_VERSION* defines that map version number to actual real |
| identifiers. This way it is easier to write comparisons without messing up with |
| version numbers. |
| |
| To *"strictly"* check the most recent detected extension: |
| |
| [source] |
| ---- |
| #include <boost/predef/hardware/simd.h> |
| #include <iostream> |
| |
| int main() |
| { |
| #if BOOST_HW_SIMD_X86 == BOOST_HW_SIMD_X86_SSE3_VERSION |
| std::cout << "This is SSE3 and this is the most recent enabled extension!" |
| << std::endl; |
| #endif |
| return 0; |
| } |
| ---- |
| |
| Because of the version systems of predefs and of the inclusive property of SIMD |
| extensions macros, you can easily check for ranges of supported extensions: |
| |
| [source] |
| ---- |
| #include <boost/predef/hardware/simd.h> |
| #include <iostream> |
| |
| int main() |
| { |
| #if BOOST_HW_SIMD_X86 >= BOOST_HW_SIMD_X86_SSE2_VERSION &&\ |
| BOOST_HW_SIMD_X86 <= BOOST_HW_SIMD_X86_SSSE3_VERSION |
| std::cout << "This is SSE2, SSE3 and SSSE3!" << std::endl; |
| #endif |
| return 0; |
| } |
| ---- |
| |
| NOTE: Unlike gcc and clang, Visual Studio does not allow you to specify precisely |
| the SSE variants you want to use, the only detections that will take place are |
| SSE, SSE2, AVX and AVX2. For more informations, |
| see [@https://msdn.microsoft.com/en-us/library/b0084kay.aspx here]. |
| |
| |
| */ // end::reference[] |
| |
| // We check if SIMD extension of multiples architectures have been detected, |
| // if yes, then this is an error! |
| // |
| // NOTE: _X86_AMD implies _X86, so there is no need to check for it here! |
| // |
| #if defined(BOOST_HW_SIMD_ARM_AVAILABLE) && defined(BOOST_HW_SIMD_PPC_AVAILABLE) ||\ |
| defined(BOOST_HW_SIMD_ARM_AVAILABLE) && defined(BOOST_HW_SIMD_X86_AVAILABLE) ||\ |
| defined(BOOST_HW_SIMD_PPC_AVAILABLE) && defined(BOOST_HW_SIMD_X86_AVAILABLE) |
| # error "Multiple SIMD architectures detected, this cannot happen!" |
| #endif |
| |
| #if defined(BOOST_HW_SIMD_X86_AVAILABLE) && defined(BOOST_HW_SIMD_X86_AMD_AVAILABLE) |
| // If both standard _X86 and _X86_AMD are available, |
| // then take the biggest version of the two! |
| # if BOOST_HW_SIMD_X86 >= BOOST_HW_SIMD_X86_AMD |
| # define BOOST_HW_SIMD BOOST_HW_SIMD_X86 |
| # else |
| # define BOOST_HW_SIMD BOOST_HW_SIMD_X86_AMD |
| # endif |
| #endif |
| |
| #if !defined(BOOST_HW_SIMD) |
| // At this point, only one of these two is defined |
| # if defined(BOOST_HW_SIMD_X86_AVAILABLE) |
| # define BOOST_HW_SIMD BOOST_HW_SIMD_X86 |
| # endif |
| # if defined(BOOST_HW_SIMD_X86_AMD_AVAILABLE) |
| # define BOOST_HW_SIMD BOOST_HW_SIMD_X86_AMD |
| # endif |
| #endif |
| |
| #if defined(BOOST_HW_SIMD_ARM_AVAILABLE) |
| # define BOOST_HW_SIMD BOOST_HW_SIMD_ARM |
| #endif |
| |
| #if defined(BOOST_HW_SIMD_PPC_AVAILABLE) |
| # define BOOST_HW_SIMD BOOST_HW_SIMD_PPC |
| #endif |
| |
| #if defined(BOOST_HW_SIMD) |
| # define BOOST_HW_SIMD_AVAILABLE |
| #else |
| # define BOOST_HW_SIMD BOOST_VERSION_NUMBER_NOT_AVAILABLE |
| #endif |
| |
| #define BOOST_HW_SIMD_NAME "Hardware SIMD" |
| |
| #endif |
| |
| #include <boost/predef/detail/test.h> |
| BOOST_PREDEF_DECLARE_TEST(BOOST_HW_SIMD, BOOST_HW_SIMD_NAME) |