[Mesa-dev] [PATCH] gallium/swr: confine c++11 flag to swr driver

Rowley, Timothy O timothy.o.rowley at intel.com
Fri Apr 15 15:55:39 UTC 2016


> On Apr 15, 2016, at 10:33 AM, Jose Fonseca <jfonseca at vmware.com> wrote:
> 
> On 15/04/16 00:30, Tim Rowley wrote:
>> On the philosophy that a driver shouldn't change the compile flags
>> for the entire tree, take the clove approach of moving the c++11 flag
>> to the swr driver directory.
>> ---
>>  configure.ac                        |   9 +-
>>  m4/ax_cxx_compile_stdcxx.m4         | 558 ------------------------------------
>>  src/gallium/drivers/swr/Makefile.am |   3 +-
>>  3 files changed, 9 insertions(+), 561 deletions(-)
>>  delete mode 100644 m4/ax_cxx_compile_stdcxx.m4
>> 
>> diff --git a/configure.ac b/configure.ac
>> index 8c82c43..6155942 100644
>> --- a/configure.ac
>> +++ b/configure.ac
>> @@ -2265,15 +2265,20 @@ if test -n "$with_gallium_drivers"; then
>>              fi
>>              ;;
>>          xswr)
>> -            AX_CXX_COMPILE_STDCXX([11], [noext], [mandatory])
>>              swr_llvm_check "swr"
>> 
>> -            AC_MSG_CHECKING([whether $CXX supports AVX/AVX2])
>> +            AC_MSG_CHECKING([whether $CXX supports c++11/AVX/AVX2])
>>              AVX_CXXFLAGS="-march=core-avx-i"
>>              AVX2_CXXFLAGS="-march=core-avx2"
>> 
>>              AC_LANG_PUSH([C++])
>>              save_CXXFLAGS="$CXXFLAGS"
>> +            CXXFLAGS="-std=c++11 $CXXFLAGS"
>> +            AC_COMPILE_IFELSE([AC_LANG_PROGRAM()],[],
>> +                              [AC_MSG_ERROR([c++11 compiler support not detected])])
>> +            CXXFLAGS="$save_CXXFLAGS"
>> +
>> +            save_CXXFLAGS="$CXXFLAGS"
>>              CXXFLAGS="$AVX_CXXFLAGS $CXXFLAGS"
>>              AC_COMPILE_IFELSE([AC_LANG_PROGRAM()],[],
>>                                [AC_MSG_ERROR([AVX compiler support not detected])])
>> diff --git a/m4/ax_cxx_compile_stdcxx.m4 b/m4/ax_cxx_compile_stdcxx.m4
>> deleted file mode 100644
>> index 079e17d..0000000
>> --- a/m4/ax_cxx_compile_stdcxx.m4
>> +++ /dev/null
>> @@ -1,558 +0,0 @@
>> -# ===========================================================================
>> -#   http://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx.html
>> -# ===========================================================================
>> -#
>> -# SYNOPSIS
>> -#
>> -#   AX_CXX_COMPILE_STDCXX(VERSION, [ext|noext], [mandatory|optional])
>> -#
>> -# DESCRIPTION
>> -#
>> -#   Check for baseline language coverage in the compiler for the specified
>> -#   version of the C++ standard.  If necessary, add switches to CXXFLAGS to
>> -#   enable support.  VERSION may be '11' (for the C++11 standard) or '14'
>> -#   (for the C++14 standard).
>> -#
>> -#   The second argument, if specified, indicates whether you insist on an
>> -#   extended mode (e.g. -std=gnu++11) or a strict conformance mode (e.g.
>> -#   -std=c++11).  If neither is specified, you get whatever works, with
>> -#   preference for an extended mode.
>> -#
>> -#   The third argument, if specified 'mandatory' or if left unspecified,
>> -#   indicates that baseline support for the specified C++ standard is
>> -#   required and that the macro should error out if no mode with that
>> -#   support is found.  If specified 'optional', then configuration proceeds
>> -#   regardless, after defining HAVE_CXX${VERSION} if and only if a
>> -#   supporting mode is found.
>> -#
>> -# LICENSE
>> -#
>> -#   Copyright (c) 2008 Benjamin Kosnik <bkoz at redhat.com>
>> -#   Copyright (c) 2012 Zack Weinberg <zackw at panix.com>
>> -#   Copyright (c) 2013 Roy Stogner <roystgnr at ices.utexas.edu>
>> -#   Copyright (c) 2014, 2015 Google Inc.; contributed by Alexey Sokolov <sokolov at google.com>
>> -#   Copyright (c) 2015 Paul Norman <penorman at mac.com>
>> -#   Copyright (c) 2015 Moritz Klammler <moritz at klammler.eu>
>> -#
>> -#   Copying and distribution of this file, with or without modification, are
>> -#   permitted in any medium without royalty provided the copyright notice
>> -#   and this notice are preserved.  This file is offered as-is, without any
>> -#   warranty.
>> -
>> -#serial 1
>> -
>> -dnl  This macro is based on the code from the AX_CXX_COMPILE_STDCXX_11 macro
>> -dnl  (serial version number 13).
>> -
>> -AC_DEFUN([AX_CXX_COMPILE_STDCXX], [dnl
>> -  m4_if([$1], [11], [],
>> -        [$1], [14], [],
>> -        [$1], [17], [m4_fatal([support for C++17 not yet implemented in AX_CXX_COMPILE_STDCXX])],
>> -        [m4_fatal([invalid first argument `$1' to AX_CXX_COMPILE_STDCXX])])dnl
>> -  m4_if([$2], [], [],
>> -        [$2], [ext], [],
>> -        [$2], [noext], [],
>> -        [m4_fatal([invalid second argument `$2' to AX_CXX_COMPILE_STDCXX])])dnl
>> -  m4_if([$3], [], [ax_cxx_compile_cxx$1_required=true],
>> -        [$3], [mandatory], [ax_cxx_compile_cxx$1_required=true],
>> -        [$3], [optional], [ax_cxx_compile_cxx$1_required=false],
>> -        [m4_fatal([invalid third argument `$3' to AX_CXX_COMPILE_STDCXX])])
>> -  AC_LANG_PUSH([C++])dnl
>> -  ac_success=no
>> -  AC_CACHE_CHECK(whether $CXX supports C++$1 features by default,
>> -  ax_cv_cxx_compile_cxx$1,
>> -  [AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])],
>> -    [ax_cv_cxx_compile_cxx$1=yes],
>> -    [ax_cv_cxx_compile_cxx$1=no])])
>> -  if test x$ax_cv_cxx_compile_cxx$1 = xyes; then
>> -    ac_success=yes
>> -  fi
>> -
>> -  m4_if([$2], [noext], [], [dnl
>> -  if test x$ac_success = xno; then
>> -    for switch in -std=gnu++$1 -std=gnu++0x; do
>> -      cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx$1_$switch])
>> -      AC_CACHE_CHECK(whether $CXX supports C++$1 features with $switch,
>> -                     $cachevar,
>> -        [ac_save_CXXFLAGS="$CXXFLAGS"
>> -         CXXFLAGS="$CXXFLAGS $switch"
>> -         AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])],
>> -          [eval $cachevar=yes],
>> -          [eval $cachevar=no])
>> -         CXXFLAGS="$ac_save_CXXFLAGS"])
>> -      if eval test x\$$cachevar = xyes; then
>> -        CXXFLAGS="$CXXFLAGS $switch"
>> -        ac_success=yes
>> -        break
>> -      fi
>> -    done
>> -  fi])
>> -
>> -  m4_if([$2], [ext], [], [dnl
>> -  if test x$ac_success = xno; then
>> -    dnl HP's aCC needs +std=c++11 according to:
>> -    dnl http://h21007.www2.hp.com/portal/download/files/unprot/aCxx/PDF_Release_Notes/769149-001.pdf
>> -    dnl Cray's crayCC needs "-h std=c++11"
>> -    for switch in -std=c++$1 -std=c++0x +std=c++$1 "-h std=c++$1"; do
>> -      cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx$1_$switch])
>> -      AC_CACHE_CHECK(whether $CXX supports C++$1 features with $switch,
>> -                     $cachevar,
>> -        [ac_save_CXXFLAGS="$CXXFLAGS"
>> -         CXXFLAGS="$CXXFLAGS $switch"
>> -         AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])],
>> -          [eval $cachevar=yes],
>> -          [eval $cachevar=no])
>> -         CXXFLAGS="$ac_save_CXXFLAGS"])
>> -      if eval test x\$$cachevar = xyes; then
>> -        CXXFLAGS="$CXXFLAGS $switch"
>> -        ac_success=yes
>> -        break
>> -      fi
>> -    done
>> -  fi])
>> -  AC_LANG_POP([C++])
>> -  if test x$ax_cxx_compile_cxx$1_required = xtrue; then
>> -    if test x$ac_success = xno; then
>> -      AC_MSG_ERROR([*** A compiler with support for C++$1 language features is required.])
>> -    fi
>> -  else
>> -    if test x$ac_success = xno; then
>> -      HAVE_CXX$1=0
>> -      AC_MSG_NOTICE([No compiler with C++$1 support was found])
>> -    else
>> -      HAVE_CXX$1=1
>> -      AC_DEFINE(HAVE_CXX$1,1,
>> -                [define if the compiler supports basic C++$1 syntax])
>> -    fi
>> -
>> -    AC_SUBST(HAVE_CXX$1)
>> -  fi
>> -])
>> -
>> -
>> -dnl  Test body for checking C++11 support
>> -
>> -m4_define([_AX_CXX_COMPILE_STDCXX_testbody_11],
>> -  _AX_CXX_COMPILE_STDCXX_testbody_new_in_11
>> -)
>> -
>> -
>> -dnl  Test body for checking C++14 support
>> -
>> -m4_define([_AX_CXX_COMPILE_STDCXX_testbody_14],
>> -  _AX_CXX_COMPILE_STDCXX_testbody_new_in_11
>> -  _AX_CXX_COMPILE_STDCXX_testbody_new_in_14
>> -)
>> -
>> -
>> -dnl  Tests for new features in C++11
>> -
>> -m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_11], [[
>> -
>> -// If the compiler admits that it is not ready for C++11, why torture it?
>> -// Hopefully, this will speed up the test.
>> -
>> -#ifndef __cplusplus
>> -
>> -#error "This is not a C++ compiler"
>> -
>> -#elif __cplusplus < 201103L
>> -
>> -#error "This is not a C++11 compiler"
>> -
>> -#else
>> -
>> -namespace cxx11
>> -{
>> -
>> -  namespace test_static_assert
>> -  {
>> -
>> -    template <typename T>
>> -    struct check
>> -    {
>> -      static_assert(sizeof(int) <= sizeof(T), "not big enough");
>> -    };
>> -
>> -  }
>> -
>> -  namespace test_final_override
>> -  {
>> -
>> -    struct Base
>> -    {
>> -      virtual void f() {}
>> -    };
>> -
>> -    struct Derived : public Base
>> -    {
>> -      virtual void f() override {}
>> -    };
>> -
>> -  }
>> -
>> -  namespace test_double_right_angle_brackets
>> -  {
>> -
>> -    template < typename T >
>> -    struct check {};
>> -
>> -    typedef check<void> single_type;
>> -    typedef check<check<void>> double_type;
>> -    typedef check<check<check<void>>> triple_type;
>> -    typedef check<check<check<check<void>>>> quadruple_type;
>> -
>> -  }
>> -
>> -  namespace test_decltype
>> -  {
>> -
>> -    int
>> -    f()
>> -    {
>> -      int a = 1;
>> -      decltype(a) b = 2;
>> -      return a + b;
>> -    }
>> -
>> -  }
>> -
>> -  namespace test_type_deduction
>> -  {
>> -
>> -    template < typename T1, typename T2 >
>> -    struct is_same
>> -    {
>> -      static const bool value = false;
>> -    };
>> -
>> -    template < typename T >
>> -    struct is_same<T, T>
>> -    {
>> -      static const bool value = true;
>> -    };
>> -
>> -    template < typename T1, typename T2 >
>> -    auto
>> -    add(T1 a1, T2 a2) -> decltype(a1 + a2)
>> -    {
>> -      return a1 + a2;
>> -    }
>> -
>> -    int
>> -    test(const int c, volatile int v)
>> -    {
>> -      static_assert(is_same<int, decltype(0)>::value == true, "");
>> -      static_assert(is_same<int, decltype(c)>::value == false, "");
>> -      static_assert(is_same<int, decltype(v)>::value == false, "");
>> -      auto ac = c;
>> -      auto av = v;
>> -      auto sumi = ac + av + 'x';
>> -      auto sumf = ac + av + 1.0;
>> -      static_assert(is_same<int, decltype(ac)>::value == true, "");
>> -      static_assert(is_same<int, decltype(av)>::value == true, "");
>> -      static_assert(is_same<int, decltype(sumi)>::value == true, "");
>> -      static_assert(is_same<int, decltype(sumf)>::value == false, "");
>> -      static_assert(is_same<int, decltype(add(c, v))>::value == true, "");
>> -      return (sumf > 0.0) ? sumi : add(c, v);
>> -    }
>> -
>> -  }
>> -
>> -  namespace test_noexcept
>> -  {
>> -
>> -    int f() { return 0; }
>> -    int g() noexcept { return 0; }
>> -
>> -    static_assert(noexcept(f()) == false, "");
>> -    static_assert(noexcept(g()) == true, "");
>> -
>> -  }
>> -
>> -  namespace test_constexpr
>> -  {
>> -
>> -    template < typename CharT >
>> -    unsigned long constexpr
>> -    strlen_c_r(const CharT *const s, const unsigned long acc) noexcept
>> -    {
>> -      return *s ? strlen_c_r(s + 1, acc + 1) : acc;
>> -    }
>> -
>> -    template < typename CharT >
>> -    unsigned long constexpr
>> -    strlen_c(const CharT *const s) noexcept
>> -    {
>> -      return strlen_c_r(s, 0UL);
>> -    }
>> -
>> -    static_assert(strlen_c("") == 0UL, "");
>> -    static_assert(strlen_c("1") == 1UL, "");
>> -    static_assert(strlen_c("example") == 7UL, "");
>> -    static_assert(strlen_c("another\0example") == 7UL, "");
>> -
>> -  }
>> -
>> -  namespace test_rvalue_references
>> -  {
>> -
>> -    template < int N >
>> -    struct answer
>> -    {
>> -      static constexpr int value = N;
>> -    };
>> -
>> -    answer<1> f(int&)       { return answer<1>(); }
>> -    answer<2> f(const int&) { return answer<2>(); }
>> -    answer<3> f(int&&)      { return answer<3>(); }
>> -
>> -    void
>> -    test()
>> -    {
>> -      int i = 0;
>> -      const int c = 0;
>> -      static_assert(decltype(f(i))::value == 1, "");
>> -      static_assert(decltype(f(c))::value == 2, "");
>> -      static_assert(decltype(f(0))::value == 3, "");
>> -    }
>> -
>> -  }
>> -
>> -  namespace test_uniform_initialization
>> -  {
>> -
>> -    struct test
>> -    {
>> -      static const int zero {};
>> -      static const int one {1};
>> -    };
>> -
>> -    static_assert(test::zero == 0, "");
>> -    static_assert(test::one == 1, "");
>> -
>> -  }
>> -
>> -  namespace test_lambdas
>> -  {
>> -
>> -    void
>> -    test1()
>> -    {
>> -      auto lambda1 = [](){};
>> -      auto lambda2 = lambda1;
>> -      lambda1();
>> -      lambda2();
>> -    }
>> -
>> -    int
>> -    test2()
>> -    {
>> -      auto a = [](int i, int j){ return i + j; }(1, 2);
>> -      auto b = []() -> int { return '0'; }();
>> -      auto c = [=](){ return a + b; }();
>> -      auto d = [&](){ return c; }();
>> -      auto e = [a, &b](int x) mutable {
>> -        const auto identity = [](int y){ return y; };
>> -        for (auto i = 0; i < a; ++i)
>> -          a += b--;
>> -        return x + identity(a + b);
>> -      }(0);
>> -      return a + b + c + d + e;
>> -    }
>> -
>> -    int
>> -    test3()
>> -    {
>> -      const auto nullary = [](){ return 0; };
>> -      const auto unary = [](int x){ return x; };
>> -      using nullary_t = decltype(nullary);
>> -      using unary_t = decltype(unary);
>> -      const auto higher1st = [](nullary_t f){ return f(); };
>> -      const auto higher2nd = [unary](nullary_t f1){
>> -        return [unary, f1](unary_t f2){ return f2(unary(f1())); };
>> -      };
>> -      return higher1st(nullary) + higher2nd(nullary)(unary);
>> -    }
>> -
>> -  }
>> -
>> -  namespace test_variadic_templates
>> -  {
>> -
>> -    template <int...>
>> -    struct sum;
>> -
>> -    template <int N0, int... N1toN>
>> -    struct sum<N0, N1toN...>
>> -    {
>> -      static constexpr auto value = N0 + sum<N1toN...>::value;
>> -    };
>> -
>> -    template <>
>> -    struct sum<>
>> -    {
>> -      static constexpr auto value = 0;
>> -    };
>> -
>> -    static_assert(sum<>::value == 0, "");
>> -    static_assert(sum<1>::value == 1, "");
>> -    static_assert(sum<23>::value == 23, "");
>> -    static_assert(sum<1, 2>::value == 3, "");
>> -    static_assert(sum<5, 5, 11>::value == 21, "");
>> -    static_assert(sum<2, 3, 5, 7, 11, 13>::value == 41, "");
>> -
>> -  }
>> -
>> -  // http://stackoverflow.com/questions/13728184/template-aliases-and-sfinae
>> -  // Clang 3.1 fails with headers of libstd++ 4.8.3 when using std::function
>> -  // because of this.
>> -  namespace test_template_alias_sfinae
>> -  {
>> -
>> -    struct foo {};
>> -
>> -    template<typename T>
>> -    using member = typename T::member_type;
>> -
>> -    template<typename T>
>> -    void func(...) {}
>> -
>> -    template<typename T>
>> -    void func(member<T>*) {}
>> -
>> -    void test();
>> -
>> -    void test() { func<foo>(0); }
>> -
>> -  }
>> -
>> -}  // namespace cxx11
>> -
>> -#endif  // __cplusplus >= 201103L
>> -
>> -]])
>> -
>> -
>> -dnl  Tests for new features in C++14
>> -
>> -m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_14], [[
>> -
>> -// If the compiler admits that it is not ready for C++14, why torture it?
>> -// Hopefully, this will speed up the test.
>> -
>> -#ifndef __cplusplus
>> -
>> -#error "This is not a C++ compiler"
>> -
>> -#elif __cplusplus < 201402L
>> -
>> -#error "This is not a C++14 compiler"
>> -
>> -#else
>> -
>> -namespace cxx14
>> -{
>> -
>> -  namespace test_polymorphic_lambdas
>> -  {
>> -
>> -    int
>> -    test()
>> -    {
>> -      const auto lambda = [](auto&&... args){
>> -        const auto istiny = [](auto x){
>> -          return (sizeof(x) == 1UL) ? 1 : 0;
>> -        };
>> -        const int aretiny[] = { istiny(args)... };
>> -        return aretiny[0];
>> -      };
>> -      return lambda(1, 1L, 1.0f, '1');
>> -    }
>> -
>> -  }
>> -
>> -  namespace test_binary_literals
>> -  {
>> -
>> -    constexpr auto ivii = 0b0000000000101010;
>> -    static_assert(ivii == 42, "wrong value");
>> -
>> -  }
>> -
>> -  namespace test_generalized_constexpr
>> -  {
>> -
>> -    template < typename CharT >
>> -    constexpr unsigned long
>> -    strlen_c(const CharT *const s) noexcept
>> -    {
>> -      auto length = 0UL;
>> -      for (auto p = s; *p; ++p)
>> -        ++length;
>> -      return length;
>> -    }
>> -
>> -    static_assert(strlen_c("") == 0UL, "");
>> -    static_assert(strlen_c("x") == 1UL, "");
>> -    static_assert(strlen_c("test") == 4UL, "");
>> -    static_assert(strlen_c("another\0test") == 7UL, "");
>> -
>> -  }
>> -
>> -  namespace test_lambda_init_capture
>> -  {
>> -
>> -    int
>> -    test()
>> -    {
>> -      auto x = 0;
>> -      const auto lambda1 = [a = x](int b){ return a + b; };
>> -      const auto lambda2 = [a = lambda1(x)](){ return a; };
>> -      return lambda2();
>> -    }
>> -
>> -  }
>> -
>> -  namespace test_digit_seperators
>> -  {
>> -
>> -    constexpr auto ten_million = 100'000'000;
>> -    static_assert(ten_million == 100000000, "");
>> -
>> -  }
>> -
>> -  namespace test_return_type_deduction
>> -  {
>> -
>> -    auto f(int& x) { return x; }
>> -    decltype(auto) g(int& x) { return x; }
>> -
>> -    template < typename T1, typename T2 >
>> -    struct is_same
>> -    {
>> -      static constexpr auto value = false;
>> -    };
>> -
>> -    template < typename T >
>> -    struct is_same<T, T>
>> -    {
>> -      static constexpr auto value = true;
>> -    };
>> -
>> -    int
>> -    test()
>> -    {
>> -      auto x = 0;
>> -      static_assert(is_same<int, decltype(f(x))>::value, "");
>> -      static_assert(is_same<int&, decltype(g(x))>::value, "");
>> -      return x;
>> -    }
>> -
>> -  }
>> -
>> -}  // namespace cxx14It also includes other options you want,
>> -
>> -#endif  // __cplusplus >= 201402L
>> -
>> -]])
>> diff --git a/src/gallium/drivers/swr/Makefile.am b/src/gallium/drivers/swr/Makefile.am
>> index d6d6e7d..12bb42e 100644
>> --- a/src/gallium/drivers/swr/Makefile.am
>> +++ b/src/gallium/drivers/swr/Makefile.am
>> @@ -22,7 +22,7 @@
>>  include Makefile.sources
>>  include $(top_srcdir)/src/gallium/Automake.inc
>> 
>> -AM_CXXFLAGS = $(GALLIUM_DRIVER_CFLAGS)
>> +AM_CXXFLAGS = $(GALLIUM_DRIVER_CFLAGS) -std=c++11
>> 
>>  noinst_LTLIBRARIES = libmesaswr.la
>> 
>> @@ -31,6 +31,7 @@ libmesaswr_la_SOURCES = $(LOADER_SOURCES)
>>  COMMON_CXXFLAGS = \
>>  	$(GALLIUM_DRIVER_CFLAGS) \
>>  	$(LLVM_CFLAGS) \
>> +	-std=c++11 \
> 
> I think that if instead of using LLVM_CFLAGS you used LLVM_CXXFLAGS you wouldn't anything more
> 
> As LLVM_CXXFLAGS / `llvm-config --cxxflags` already includes std=c++11

Yes, I saw that and considered going that direction, but wasn’t sure if we should rely on llvm setting the language version required.

>>  	-I$(builddir)/rasterizer/scripts \
>>  	-I$(builddir)/rasterizer/jitter \
>>  	-I$(srcdir)/rasterizer \
>> 
> 
> Either way,
> 
> Acked-by: Jose Fonseca <jfonseca at vmware.com>
> 
> Jose



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