diff options
| author | Matthias Kretz <m.kretz@gsi.de> | 2023-01-13 16:20:36 +0100 |
|---|---|---|
| committer | Matthias Kretz <m.kretz@gsi.de> | 2023-02-16 15:58:33 +0100 |
| commit | fea34ee491104f325682cc5fb75683b7d74a0a3b (patch) | |
| tree | ec55aa58014371348f525117f550f6fcb53bc7c0 | |
| parent | feff71e035c2948c3e4cbcc06adf1ed633e3bd50 (diff) | |
| download | gcc-fea34ee491104f325682cc5fb75683b7d74a0a3b.zip gcc-fea34ee491104f325682cc5fb75683b7d74a0a3b.tar.gz gcc-fea34ee491104f325682cc5fb75683b7d74a0a3b.tar.bz2 | |
libstdc++: Ensure __builtin_constant_p isn't lost on the way
The more expensive code path should only be taken if it can be optimized
away.
Signed-off-by: Matthias Kretz <m.kretz@gsi.de>
libstdc++-v3/ChangeLog:
* include/experimental/bits/simd.h
(_SimdWrapper::_M_is_constprop_none_of)
(_SimdWrapper::_M_is_constprop_all_of): Return false unless the
computed result still satisfies __builtin_constant_p.
| -rw-r--r-- | libstdc++-v3/include/experimental/bits/simd.h | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/libstdc++-v3/include/experimental/bits/simd.h b/libstdc++-v3/include/experimental/bits/simd.h index e76f478..3de966b 100644 --- a/libstdc++-v3/include/experimental/bits/simd.h +++ b/libstdc++-v3/include/experimental/bits/simd.h @@ -2673,7 +2673,8 @@ template <typename _Tp, size_t _Width> else __execute_n_times<_Width>( [&](auto __i) { __r &= _M_data[__i.value] == _Tp(); }); - return __r; + if (__builtin_constant_p(__r)) + return __r; } return false; } @@ -2693,7 +2694,8 @@ template <typename _Tp, size_t _Width> else __execute_n_times<_Width>( [&](auto __i) { __r &= _M_data[__i.value] == ~_Tp(); }); - return __r; + if (__builtin_constant_p(__r)) + return __r; } return false; } |