libstdc++: Fix condition when AVX512F ldexp implementation is used

This improves codegen of ldexp if AVX512VL is available.

Signed-off-by: Matthias Kretz <m.kretz@gsi.de>
libstdc++-v3/ChangeLog:

	* include/experimental/bits/simd_x86.h (_S_ldexp): The AVX512F
	implementation doesn't require a _VecBltnBtmsk ABI tag, it
	requires either a 64-Byte input (in which case AVX512F must be
	available) or AVX512VL.

diff --git a/libstdc++-v3/include/experimental/bits/simd_x86.h b/libstdc++-v3/include/experimental/bits/simd_x86.h
index 305d7a9..5706bf6 100644 (file)
--- a/libstdc++-v3/include/experimental/bits/simd_x86.h
+++ b/libstdc++-v3/include/experimental/bits/simd_x86.h
@@ -2611,13 +2611,14 @@ template <typename _Abi>
       _S_ldexp(_SimdWrapper<_Tp, _Np> __x,
               __fixed_size_storage_t<int, _Np> __exp)
       {
-       if constexpr (__is_avx512_abi<_Abi>())
+       if constexpr (sizeof(__x) == 64 || __have_avx512vl)
          {
            const auto __xi = __to_intrin(__x);
            constexpr _SimdConverter<int, simd_abi::fixed_size<_Np>, _Tp, _Abi>
              __cvt;
            const auto __expi = __to_intrin(__cvt(__exp));
-           constexpr auto __k1 = _Abi::template _S_implicit_mask_intrin<_Tp>();
+           using _Up = __bool_storage_member_type_t<_Np>;
+           constexpr _Up __k1 = _Np < sizeof(_Up) * __CHAR_BIT__ ? _Up((1ULL << _Np) - 1) : ~_Up();
            if constexpr (sizeof(__xi) == 16)
              {
                if constexpr (sizeof(_Tp) == 8)