Doesn't build on powerpc64

[pkubaj]

I'm building as part of SuperCollider with LLVM 11 rc2 on FreeBSD:

/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/vec/vec_int_altivec.hpp:38:23: error: non-constant-expression cannot be narrowed from type 'int' to 'unsigned int' in initializer list [-Wc++11-narrowing]
        return (ivec){i, i, i, i};
                      ^
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/vec/vec_int_altivec.hpp:38:23: note: insert an explicit cast to silence this issue
        return (ivec){i, i, i, i};
                      ^
                      static_cast<unsigned int>( )
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/vec/vec_int_altivec.hpp:38:26: error: non-constant-expression cannot be narrowed from type 'int' to 'unsigned int' in initializer list [-Wc++11-narrowing]
        return (ivec){i, i, i, i};
                         ^
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/vec/vec_int_altivec.hpp:38:26: note: insert an explicit cast to silence this issue
        return (ivec){i, i, i, i};
                         ^
                         static_cast<unsigned int>( )
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/vec/vec_int_altivec.hpp:38:29: error: non-constant-expression cannot be narrowed from type 'int' to 'unsigned int' in initializer list [-Wc++11-narrowing]
        return (ivec){i, i, i, i};
                            ^
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/vec/vec_int_altivec.hpp:38:29: note: insert an explicit cast to silence this issue
        return (ivec){i, i, i, i};
                            ^
                            static_cast<unsigned int>( )
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/vec/vec_int_altivec.hpp:38:32: error: non-constant-expression cannot be narrowed from type 'int' to 'unsigned int' in initializer list [-Wc++11-narrowing]
        return (ivec){i, i, i, i};
                               ^
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/vec/vec_int_altivec.hpp:38:32: note: insert an explicit cast to silence this issue
        return (ivec){i, i, i, i};
                               ^
                               static_cast<unsigned int>( )
4 errors generated.

The following patch fixes build, but I'm not sure whether it causes any runtime issues:

--- external_libraries/nova-simd/vec/vec_int_altivec.hpp.orig   2020-09-03 23:55:08.848538000 +0200
+++ external_libraries/nova-simd/vec/vec_int_altivec.hpp        2020-09-03 23:58:16.614642000 +0200
@@ -35,7 +35,7 @@
     static ivec set_vector(int i)
     {
 #ifdef __GNUC__
-        return (ivec){i, i, i, i};
+        return (ivec){static_cast<unsigned int>(i), static_cast<unsigned int>(i), static_cast<unsigned int>(i), static_cast<unsigned int>(i)};
 #else
 #error compiler not supported
 #endif 

[timblechmann]

could you create a PR? i cannot test it, but if you're running on a ppc hardware, it might be a good idea to execute the unit tests

[pkubaj]

Tests currently don't build:

pkubaj@talos:$/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite$ make
[  3%] Linking CXX executable simd_unit_conversion_tests
[  6%] Built target simd_unit_conversion_tests
[ 10%] Building CXX object testsuite/CMakeFiles/simd_unary_tests.dir/simd_unary_tests.cpp.o
In file included from /tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/simd_unary_tests.cpp:4:
/usr/local/include/boost/test/floating_point_comparison.hpp:14:1: warning: This header is deprecated. Use This header is deprecated. Please use <boost/test/tools/floating_point_comparison.hpp> instead. instead. [-W#pragma-messages]
BOOST_HEADER_DEPRECATED( "This header is deprecated. Please use <boost/test/tools/floating_point_comparison.hpp> instead." )
^
/usr/local/include/boost/config/header_deprecated.hpp:23:37: note: expanded from macro 'BOOST_HEADER_DEPRECATED'
# define BOOST_HEADER_DEPRECATED(a) BOOST_PRAGMA_MESSAGE("This header is deprecated. Use " a " instead.")
                                    ^
/usr/local/include/boost/config/pragma_message.hpp:24:34: note: expanded from macro 'BOOST_PRAGMA_MESSAGE'
# define BOOST_PRAGMA_MESSAGE(x) _Pragma(BOOST_STRINGIZE(message(x)))
                                 ^
<scratch space>:105:2: note: expanded from here
 message("This header is deprecated. Use " "This header is deprecated. Please use <boost/test/tools/floating_point_comparison.hpp> instead." " instead.")
 ^
In file included from /tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/simd_unary_tests.cpp:8:
In file included from /tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/test_helper.hpp:1:
/usr/local/include/boost/test/floating_point_comparison.hpp:14:1: warning: This header is deprecated. Use This header is deprecated. Please use <boost/test/tools/floating_point_comparison.hpp> instead. instead. [-W#pragma-messages]
BOOST_HEADER_DEPRECATED( "This header is deprecated. Please use <boost/test/tools/floating_point_comparison.hpp> instead." )
^
/usr/local/include/boost/config/header_deprecated.hpp:23:37: note: expanded from macro 'BOOST_HEADER_DEPRECATED'
# define BOOST_HEADER_DEPRECATED(a) BOOST_PRAGMA_MESSAGE("This header is deprecated. Use " a " instead.")
                                    ^
/usr/local/include/boost/config/pragma_message.hpp:24:34: note: expanded from macro 'BOOST_PRAGMA_MESSAGE'
# define BOOST_PRAGMA_MESSAGE(x) _Pragma(BOOST_STRINGIZE(message(x)))
                                 ^
<scratch space>:108:2: note: expanded from here
 message("This header is deprecated. Use " "This header is deprecated. Please use <boost/test/tools/floating_point_comparison.hpp> instead." " instead.")
 ^
In file included from /tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/simd_unary_tests.cpp:11:
In file included from /tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/../simd_unary_arithmetic.hpp:22:
In file included from /tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/../vec/../detail/../vec.hpp:23:
In file included from /tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/../vec/vec_generic.hpp:28:
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/../vec/../detail/math.hpp:323:9: error: no viable conversion from 'nova::vec<float>' to 'bool'
    if (arg > 0) {
        ^~~~~~~
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/../simd_unary_arithmetic.hpp:63:37: note: in instantiation of function template specialization 'nova::detail::undenormalize<nova::vec<float>>' requested here
DEFINE_UNARY_FUNCTOR(undenormalize, undenormalize)
                                    ^
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/../vec/../detail/unroll_helpers.hpp:95:27: note: in instantiation of function template specialization 'nova::detail::undenormalize_::operator()<float>' requested here
        vec_type result = f(loaded_in1);
                          ^
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/../vec/../detail/unroll_helpers.hpp:47:46: note: in instantiation of function template specialization 'nova::detail::compile_time_unroller<float, 16>::mp_iteration_1<nova::detail::vector_pointer_argument<float>,
nova::detail::undenormalize_>' requested here
        compile_time_unroller<FloatType, N>::mp_iteration_1(out, in1.consume(), in1, f);
                                             ^
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/../vec/../detail/unroll_helpers.hpp:232:62: note: in instantiation of function template specialization 'nova::detail::compile_time_unroller<float, 16>::run<nova::detail::vector_pointer_argument<float>, nova::detail::undenormalize_>' requested here
        detail::compile_time_unroller<float_type, per_loop>::run(out, arg1, f);
                                                             ^
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/../detail/define_macros.hpp:47:23: note: in instantiation of function template specialization 'nova::detail::generate_simd_loop<float, nova::detail::vector_pointer_argument<float>, nova::detail::undenormalize_>'
requested here
        nova::detail::generate_simd_loop(out, nova::detail::wrap_vector_arg(wrap_argument(arg)), n, Functor());
                      ^
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/../simd_unary_arithmetic.hpp:78:1: note: in instantiation of function template specialization 'nova::detail::unary_functor<nova::detail::undenormalize_>::perform_vec_simd<float>' requested here
NOVA_SIMD_DEFINE_UNARY_WRAPPER(undenormalize, detail::undenormalize_)
^
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/../detail/define_macros.hpp:183:43: note: expanded from macro 'NOVA_SIMD_DEFINE_UNARY_WRAPPER'
    nova::detail::unary_functor<FUNCTOR>::perform_vec_simd<FloatType>(out, arg, n); \
                                          ^
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/simd_unary_tests.cpp:152:11: note: in instantiation of function template specialization 'nova::undenormalize_vec_simd<float>' requested here
    nova::undenormalize_vec_simd<float_type>(out_simd.c_array(), in.c_array(), size);
          ^
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/simd_unary_tests.cpp:160:5: note: in instantiation of function template specialization 'undenormalize_compare<float>' requested here
    undenormalize_compare<float>();
    ^
/tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite/../vec/vec_altivec.hpp:190:5: note: candidate function
    operator internal_vector_type (void) const
    ^
2 warnings and 1 error generated.
*** Error code 1

Stop.
make[2]: stopped in /tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd
*** Error code 1

Stop.
make[1]: stopped in /tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd
*** Error code 1

Stop.
make: stopped in /tmp/usr/ports/audio/supercollider/work/SuperCollider-3.11.0-Source/external_libraries/nova-simd/testsuite

[timblechmann]

i'm not sure if the ppc/altivec code was ever used in production, i merely wrote the altivec version as a proof of concept with a gcc of 10 years ago and tested it on qemu.
it seems that some parts might need some more love

[pkubaj]

If you'd like to fix it, but don't have the hardware, there are free PPC64 VM's for FOSS devs provided by OSU or Minicloud.