config_host/config_global.h.in | 5 +++++ configure.ac | 22 ++++++++++++++++++++++ include/o3tl/sorted_vector.hxx | 4 ++-- sc/source/core/tool/token.cxx | 3 +++ 4 files changed, 32 insertions(+), 2 deletions(-)
New commits: commit 689dc632875c4ec51e44cf53718d625d9a217d9c Author: Stephan Bergmann <sberg...@redhat.com> AuthorDate: Wed Sep 25 14:43:16 2019 +0200 Commit: Stephan Bergmann <sberg...@redhat.com> CommitDate: Wed Sep 25 20:55:53 2019 +0200 constinit, here we come Following up on b13421011d9377676e1adc282634991d5064a866 "better data structures for some static const vars": * Make the o3tl::sorted_vector ctor taking an initializer_list constexpr. <https://wg21.link/P0202R3> "Add Constexpr Modifiers to Functions in <algorithm> and <utility> Headers", which will be in C++2a and is already implemented by recent libc++ and libstdc++ according to <https://en.cppreference.com/w/cpp/compiler_support #C.2B.2B2a_library_features>, makes std::sort constexpr but explicitly keeps std::stable_sort non-constexpr. ("Algorithms stable_partition, inplace_merge and stable_sort allocate memory, construct variables using placement new, use unique_ptr and do other things not acceptable in constexpr expressions. Making those algorithms constexpr seems to be a hard task that would require a lot of intrinsics. Those algorithms are not marked with constexpr in this wording.") But keep o3tl::sorted_vector::Resort (which was introduced in c59355e936446fe55960209e543b072acb6b2170 "fdo#58793: re-implement SwpHintsArray::Resort()") using std::stable_sort instead of std::sort, in case that is relevant for its pre-exisiting uses. * <https://wg21.link/P1004R2> "Making std::vector constexpr", which was voted into C++2a according to <https://wg21.link/n4829> "Editors' Report -- Programming Languages -- C++", will make the relevant parts of std::vector constexpr. But none of libc++, libstdc++, and MSVC implement that as of now. * Introduce HAVE_CPP_CONSTINIT_SORTED_VECTOR to hide the constinit behind for now for the one case from b13421011d9377676e1adc282634991d5064a866 "better data structures for some static const vars" that can clearly be constinit once constexpr std::vector is supported by compilers. The other three cases (s_aContainerDocumentCommands in chart2/source/controller/main/CommandDispatchContainer.cxx, aMetricCompatibleMap in vcl/source/font/PhysicalFontCollection.cxx, and aBlacklist in writerfilter/source/dmapper/PropertyMap.cxx) would each need a constexpr OUString first. (Technically, the constinit would not even be needed, but it nicely documents our intent that this will actually be initialized at compile-time once compilers support that.) Change-Id: Ibeb138f120528be3a7a09b3912143bf795fbab29 Reviewed-on: https://gerrit.libreoffice.org/79556 Tested-by: Jenkins Reviewed-by: Stephan Bergmann <sberg...@redhat.com> diff --git a/config_host/config_global.h.in b/config_host/config_global.h.in index 2e986fbe24b6..adb36c39ab8b 100644 --- a/config_host/config_global.h.in +++ b/config_host/config_global.h.in @@ -24,6 +24,11 @@ Any change in this header will cause a rebuild of almost everything. /* Guaranteed copy elision (C++17), __cpp_guaranteed_copy_elision (C++2a): */ #define HAVE_CPP_GUARANTEED_COPY_ELISION 0 +// Compiler supports all of C++2a <https://wg21.link/P0202R3> "Add Constexpr Modifiers to Functions +// in <algorithm> and <utility> Headers", <https://wg21.link/P1004R2> "Making std::vector +// constexpr", and <https://wg21.link/P1143R2> "Adding the constinit keyword": +#define HAVE_CPP_CONSTINIT_SORTED_VECTOR 0 + /* GCC bug <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87150> "move ctor wrongly chosen in return stmt (derived vs. base)": */ #define HAVE_GCC_BUG_87150 0 diff --git a/configure.ac b/configure.ac index 88c512c2635f..eb08a5883eda 100644 --- a/configure.ac +++ b/configure.ac @@ -6618,6 +6618,28 @@ AC_COMPILE_IFELSE([AC_LANG_SOURCE([ CXXFLAGS=$save_CXXFLAGS AC_LANG_POP([C++]) +AC_MSG_CHECKING([whether $CXX_BASE supports C++2a constinit sorted vectors]) +AC_LANG_PUSH([C++]) +save_CXXFLAGS=$CXXFLAGS +CXXFLAGS="$CXXFLAGS $CXXFLAGS_CXX11" +AC_COMPILE_IFELSE([AC_LANG_SOURCE([ + #include <algorithm> + #include <initializer_list> + #include <vector> + template<typename T> class S { + private: + std::vector<T> v_; + public: + constexpr S(std::initializer_list<T> i): v_(i) { std::sort(v_.begin(), v_.end()); } + }; + constinit S<int> s{3, 2, 1}; + ])], [ + AC_DEFINE([HAVE_CPP_CONSTINIT_SORTED_VECTOR],[1]) + AC_MSG_RESULT([yes]) + ], [AC_MSG_RESULT([no])]) +CXXFLAGS=$save_CXXFLAGS +AC_LANG_POP([C++]) + AC_MSG_CHECKING([whether $CXX_BASE has GCC bug 87150]) AC_LANG_PUSH([C++]) save_CXXFLAGS=$CXXFLAGS diff --git a/include/o3tl/sorted_vector.hxx b/include/o3tl/sorted_vector.hxx index 527f34e568c7..102287d52a21 100644 --- a/include/o3tl/sorted_vector.hxx +++ b/include/o3tl/sorted_vector.hxx @@ -45,10 +45,10 @@ public: typedef typename std::vector<Value>::difference_type difference_type; typedef typename std::vector<Value>::size_type size_type; - sorted_vector( std::initializer_list<Value> init ) + constexpr sorted_vector( std::initializer_list<Value> init ) : m_vector(init) { - Resort(); + std::sort(m_vector.begin(), m_vector.end(), Compare()); } sorted_vector() = default; sorted_vector(sorted_vector const&) = default; diff --git a/sc/source/core/tool/token.cxx b/sc/source/core/tool/token.cxx index b9048dd25f19..475fcf16d189 100644 --- a/sc/source/core/tool/token.cxx +++ b/sc/source/core/tool/token.cxx @@ -1277,6 +1277,9 @@ bool ScTokenArray::AddFormulaToken( void ScTokenArray::CheckForThreading( const FormulaToken& r ) { +#if HAVE_CPP_CONSTINIT_SORTED_VECTOR + constinit +#endif static const o3tl::sorted_vector<OpCode> aThreadedCalcBlackList({ ocIndirect, ocMacro, _______________________________________________ Libreoffice-commits mailing list libreoffice-comm...@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/libreoffice-commits