Tested on aarch64-linux-gnu, arm-linux-gnueabihf, powerpc64le-linux-gnu,
x86_64-linux-gnu (-m64, -m32, -mx32), and arm-linux-gnueabi
OK for trunk? And when backporting, should I squash it with the commit that
introduced the regression?
8< ---
This resolves a regression on i686 that was introduced with
r15-429-gfb1649f8b4ad50.
Signed-off-by: Matthias Kretz
libstdc++-v3/ChangeLog:
PR libstdc++/114958
* include/experimental/bits/simd.h (__as_vector): Don't use
vector_size(8) on __i386__.
(__vec_shuffle): Never return MMX vectors, widen to 16 bytes
instead.
(concat): Fix padding calculation to pick up widening logic from
__as_vector.
---
libstdc++-v3/include/experimental/bits/simd.h | 39 +--
1 file changed, 28 insertions(+), 11 deletions(-)
--
──
Dr. Matthias Kretz https://mattkretz.github.io
GSI Helmholtz Centre for Heavy Ion Research https://gsi.de
stdₓ::simd
──diff --git a/libstdc++-v3/include/experimental/bits/simd.h b/libstdc++-v3/include/experimental/bits/simd.h
index 6a6fd4f109d..7c524625719 100644
--- a/libstdc++-v3/include/experimental/bits/simd.h
+++ b/libstdc++-v3/include/experimental/bits/simd.h
@@ -1665,7 +1665,12 @@ __as_vector(_V __x)
{
static_assert(is_simd<_V>::value);
using _Tp = typename _V::value_type;
+#ifdef __i386__
+ constexpr auto __bytes = sizeof(_Tp) == 8 ? 16 : sizeof(_Tp);
+ using _RV [[__gnu__::__vector_size__(__bytes)]] = _Tp;
+#else
using _RV [[__gnu__::__vector_size__(sizeof(_Tp))]] = _Tp;
+#endif
return _RV{__data(__x)};
}
}
@@ -2081,11 +2086,14 @@ __not(_Tp __a) noexcept
// }}}
// __vec_shuffle{{{
template
- _GLIBCXX_SIMD_INTRINSIC constexpr auto
+ _GLIBCXX_SIMD_INTRINSIC constexpr
+ __vector_type_t()[0])>, sizeof...(_Is)>
__vec_shuffle(_T0 __x, _T1 __y, index_sequence<_Is...> __seq, _Fun __idx_perm)
{
constexpr int _N0 = sizeof(__x) / sizeof(__x[0]);
constexpr int _N1 = sizeof(__y) / sizeof(__y[0]);
+using _Tp = remove_reference_t()[0])>;
+using _RV [[maybe_unused]] = __vector_type_t<_Tp, sizeof...(_Is)>;
#if __has_builtin(__builtin_shufflevector)
#ifdef __clang__
// Clang requires _T0 == _T1
@@ -2105,14 +2113,23 @@ __not(_Tp __a) noexcept
});
else
#endif
- return __builtin_shufflevector(__x, __y, [=] {
- constexpr int __j = __idx_perm(_Is);
- static_assert(__j < _N0 + _N1);
- return __j;
- }()...);
+ {
+ const auto __r = __builtin_shufflevector(__x, __y, [=] {
+ constexpr int __j = __idx_perm(_Is);
+ static_assert(__j < _N0 + _N1);
+ return __j;
+ }()...);
+#ifdef __i386__
+ if constexpr (sizeof(__r) == sizeof(_RV))
+ return __r;
+ else
+ return _RV {__r[_Is]...};
+#else
+ return __r;
+#endif
+ }
#else
-using _Tp = __remove_cvref_t;
-return __vector_type_t<_Tp, sizeof...(_Is)> {
+return _RV {
[=]() -> _Tp {
constexpr int __j = __idx_perm(_Is);
static_assert(__j < _N0 + _N1);
@@ -4393,9 +4410,9 @@ for (unsigned __j = 0; __j < __i; ++__j)
__vec_shuffle(__as_vector(__xs)..., std::make_index_sequence<_RW::_S_full_size>(),
[](int __i) {
constexpr int __sizes[2] = {int(simd_size_v<_Tp, _As>)...};
-constexpr int __padding0
- = sizeof(__vector_type_t<_Tp, __sizes[0]>) / sizeof(_Tp)
- - __sizes[0];
+constexpr int __vsizes[2]
+ = {int(sizeof(__as_vector(__xs)) / sizeof(_Tp))...};
+constexpr int __padding0 = __vsizes[0] - __sizes[0];
return __i >= _Np ? -1 : __i < __sizes[0] ? __i : __i + __padding0;
})};
}
