* [PATCH 0/2] Make std::experimental::simd (more) usable with Clang
@ 2023-03-21 9:22 Matthias Kretz
2023-03-21 9:23 ` [PATCH 1/2] libstdc++: Fix simd test compilation " Matthias Kretz
2023-03-21 9:23 ` [PATCH 2/2] libstdc++: Fix simd " Matthias Kretz
0 siblings, 2 replies; 6+ messages in thread
From: Matthias Kretz @ 2023-03-21 9:22 UTC (permalink / raw)
To: gcc-patches, libstdc++
Up to now, compiling std::experimental::simd with Clang would lead to wrong
code, not compiling, or ICEs. After these patches I hope it's only ICEs.
Tested on x86_64-pc-linux-gnu.
Matthias Kretz (2):
libstdc++: Fix simd test compilation with Clang
libstdc++: Fix simd compilation with Clang
.../include/experimental/bits/simd_detail.h | 2 +-
.../include/experimental/bits/simd_x86.h | 59 +++++++++++++++++--
.../experimental/simd/tests/operators.cc | 9 ++-
3 files changed, 64 insertions(+), 6 deletions(-)
--
──────────────────────────────────────────────────────────────────────────
Dr. Matthias Kretz https://mattkretz.github.io
GSI Helmholtz Centre for Heavy Ion Research https://gsi.de
stdₓ::simd
──────────────────────────────────────────────────────────────────────────
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/2] libstdc++: Fix simd test compilation with Clang
2023-03-21 9:22 [PATCH 0/2] Make std::experimental::simd (more) usable with Clang Matthias Kretz
@ 2023-03-21 9:23 ` Matthias Kretz
2023-03-21 11:16 ` Jonathan Wakely
2023-03-21 9:23 ` [PATCH 2/2] libstdc++: Fix simd " Matthias Kretz
1 sibling, 1 reply; 6+ messages in thread
From: Matthias Kretz @ 2023-03-21 9:23 UTC (permalink / raw)
To: gcc-patches, libstdc++
[-- Attachment #1: Type: text/plain, Size: 929 bytes --]
Signed-off-by: Matthias Kretz <m.kretz@gsi.de>
libstdc++-v3/ChangeLog:
* testsuite/experimental/simd/tests/operators.cc: Clang doesn't
define __GCC_IEC_559. Use __STDC_IEC_559__ instead.
---
.../testsuite/experimental/simd/tests/operators.cc | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
--
──────────────────────────────────────────────────────────────────────────
Dr. Matthias Kretz https://mattkretz.github.io
GSI Helmholtz Centre for Heavy Ion Research https://gsi.de
stdₓ::simd
──────────────────────────────────────────────────────────────────────────
[-- Attachment #2: 0001-libstdc-Fix-simd-test-compilation-with-Clang.patch --]
[-- Type: text/x-patch, Size: 720 bytes --]
diff --git a/libstdc++-v3/testsuite/experimental/simd/tests/operators.cc b/libstdc++-v3/testsuite/experimental/simd/tests/operators.cc
index c4d91fa5d2b..72af7061c73 100644
--- a/libstdc++-v3/testsuite/experimental/simd/tests/operators.cc
+++ b/libstdc++-v3/testsuite/experimental/simd/tests/operators.cc
@@ -211,7 +211,14 @@ test()
}
// divides
- constexpr bool is_iec559 = __GCC_IEC_559 >= 2;
+ constexpr bool is_iec559 =
+#ifdef __GCC_IEC_559
+ __GCC_IEC_559 >= 2;
+#elif defined __STDC_IEC_559__
+ true;
+#else
+ false;
+#endif
if constexpr (std::is_floating_point_v<T> && !is_iec559)
{ // avoid testing subnormals and expect minor deltas for non-IEC559 float
V x = 2;
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 2/2] libstdc++: Fix simd compilation with Clang
2023-03-21 9:22 [PATCH 0/2] Make std::experimental::simd (more) usable with Clang Matthias Kretz
2023-03-21 9:23 ` [PATCH 1/2] libstdc++: Fix simd test compilation " Matthias Kretz
@ 2023-03-21 9:23 ` Matthias Kretz
2023-03-21 11:19 ` Jonathan Wakely
1 sibling, 1 reply; 6+ messages in thread
From: Matthias Kretz @ 2023-03-21 9:23 UTC (permalink / raw)
To: gcc-patches, libstdc++
[-- Attachment #1: Type: text/plain, Size: 1720 bytes --]
Clang fails to compile some constant expressions involving simd.
Therefore, just disable this non-conforming extension for clang.
Fix AVX512 blend implementation for Clang. It was converting the bitmask
to bool before, which is obviously wrong. Instead use a Clang builtin to
convert the bitmask to vector-mask before using a vector blend ?:. A
similar change is required for the masked unary implementation, because
the GCC builtins do not exist on Clang.
Signed-off-by: Matthias Kretz <m.kretz@gsi.de>
libstdc++-v3/ChangeLog:
* include/experimental/bits/simd_detail.h: Don't declare the
simd API as constexpr with Clang.
* include/experimental/bits/simd_x86.h (__movm): New.
(_S_blend_avx512): Resolve FIXME. Implement blend using __movm
and ?:.
(_SimdImplX86::_S_masked_unary): Clang does not implement the
same builtins. Implement the function using __movm, ?:, and -
operators on vector_size types instead.
---
.../include/experimental/bits/simd_detail.h | 2 +-
.../include/experimental/bits/simd_x86.h | 59 +++++++++++++++++--
2 files changed, 56 insertions(+), 5 deletions(-)
--
──────────────────────────────────────────────────────────────────────────
Dr. Matthias Kretz https://mattkretz.github.io
GSI Helmholtz Centre for Heavy Ion Research https://gsi.de
stdₓ::simd
──────────────────────────────────────────────────────────────────────────
[-- Attachment #2: 0002-libstdc-Fix-simd-compilation-with-Clang.patch --]
[-- Type: text/x-patch, Size: 4087 bytes --]
diff --git a/libstdc++-v3/include/experimental/bits/simd_detail.h b/libstdc++-v3/include/experimental/bits/simd_detail.h
index 30cc1ef0eef..f3745bf3e4c 100644
--- a/libstdc++-v3/include/experimental/bits/simd_detail.h
+++ b/libstdc++-v3/include/experimental/bits/simd_detail.h
@@ -267,7 +267,7 @@ namespace experimental
#define _GLIBCXX_SIMD_IS_UNLIKELY(__x) __builtin_expect(__x, 0)
#define _GLIBCXX_SIMD_IS_LIKELY(__x) __builtin_expect(__x, 1)
-#if defined __STRICT_ANSI__ && __STRICT_ANSI__
+#if (defined __STRICT_ANSI__ && __STRICT_ANSI__) || defined __clang__
#define _GLIBCXX_SIMD_CONSTEXPR
#define _GLIBCXX_SIMD_USE_CONSTEXPR_API const
#else
diff --git a/libstdc++-v3/include/experimental/bits/simd_x86.h b/libstdc++-v3/include/experimental/bits/simd_x86.h
index 608918542c6..165738c4e2c 100644
--- a/libstdc++-v3/include/experimental/bits/simd_x86.h
+++ b/libstdc++-v3/include/experimental/bits/simd_x86.h
@@ -363,6 +363,53 @@ __maskload_pd(const double* __ptr, _Tp __k)
// }}}
+#ifdef __clang__
+template <size_t _Np, typename _Tp, typename _Kp>
+ _GLIBCXX_SIMD_INTRINSIC constexpr auto
+ __movm(_Kp __k) noexcept
+ {
+ static_assert(is_unsigned_v<_Kp>);
+ if constexpr (sizeof(_Tp) == 1 && __have_avx512bw)
+ {
+ if constexpr (_Np <= 16 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2b128(__k);
+ else if constexpr (_Np <= 32 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2b256(__k);
+ else
+ return __builtin_ia32_cvtmask2b512(__k);
+ }
+ else if constexpr (sizeof(_Tp) == 2 && __have_avx512bw)
+ {
+ if constexpr (_Np <= 8 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2w128(__k);
+ else if constexpr (_Np <= 16 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2w256(__k);
+ else
+ return __builtin_ia32_cvtmask2w512(__k);
+ }
+ else if constexpr (sizeof(_Tp) == 4 && __have_avx512dq)
+ {
+ if constexpr (_Np <= 4 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2d128(__k);
+ else if constexpr (_Np <= 8 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2d256(__k);
+ else
+ return __builtin_ia32_cvtmask2d512(__k);
+ }
+ else if constexpr (sizeof(_Tp) == 8 && __have_avx512dq)
+ {
+ if constexpr (_Np <= 2 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2q128(__k);
+ else if constexpr (_Np <= 4 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2q256(__k);
+ else
+ return __builtin_ia32_cvtmask2q512(__k);
+ }
+ else
+ __assert_unreachable<_Tp>();
+ }
+#endif // __clang__
+
#ifdef _GLIBCXX_SIMD_WORKAROUND_PR85048
#include "simd_x86_conversions.h"
#endif
@@ -619,14 +666,13 @@ _pdep_u32(
_GLIBCXX_SIMD_INTRINSIC static _TV
_S_blend_avx512(const _Kp __k, const _TV __a, const _TV __b) noexcept
{
-#ifdef __clang__
- // FIXME: this does a boolean choice, not a blend
- return __k ? __a : __b;
-#else
static_assert(__is_vector_type_v<_TV>);
using _Tp = typename _VectorTraits<_TV>::value_type;
static_assert(sizeof(_TV) >= 16);
static_assert(sizeof(_Tp) <= 8);
+#ifdef __clang__
+ return __movm<_VectorTraits<_TV>::_S_full_size, _Tp>(__k) ? __b : __a;
+#else
using _IntT
= conditional_t<(sizeof(_Tp) > 2),
conditional_t<sizeof(_Tp) == 4, int, long long>,
@@ -3483,6 +3529,10 @@ _S_masked_unary(const _SimdWrapper<_K, _Np> __k, const _SimdWrapper<_Tp, _Np> __
// optimize masked unary increment and decrement as masked sub +/-1
constexpr int __pm_one
= is_same_v<_Op<void>, __increment<void>> ? -1 : 1;
+#ifdef __clang__
+ return __vector_bitcast<_Tp, _Np>(__movm<_Np, _Tp>(__k._M_data))
+ ? __v._M_data - __pm_one : __v._M_data;
+#else // __clang__
if constexpr (is_integral_v<_Tp>)
{
constexpr bool __lp64 = sizeof(long) == sizeof(long long);
@@ -3526,6 +3576,7 @@ _S_masked_unary(const _SimdWrapper<_K, _Np> __k, const _SimdWrapper<_Tp, _Np> __
_GLIBCXX_SIMD_MASK_SUB(8, 16, subpd128);
#undef _GLIBCXX_SIMD_MASK_SUB
}
+#endif // __clang__
}
else
return _Base::template _S_masked_unary<_Op>(__k, __v);
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/2] libstdc++: Fix simd test compilation with Clang
2023-03-21 9:23 ` [PATCH 1/2] libstdc++: Fix simd test compilation " Matthias Kretz
@ 2023-03-21 11:16 ` Jonathan Wakely
0 siblings, 0 replies; 6+ messages in thread
From: Jonathan Wakely @ 2023-03-21 11:16 UTC (permalink / raw)
To: Matthias Kretz; +Cc: gcc-patches, libstdc++
[-- Attachment #1: Type: text/plain, Size: 327 bytes --]
On Tue, 21 Mar 2023 at 09:24, Matthias Kretz via Libstdc++ <
libstdc++@gcc.gnu.org> wrote:
>
>
> Signed-off-by: Matthias Kretz <m.kretz@gsi.de>
>
> libstdc++-v3/ChangeLog:
>
> * testsuite/experimental/simd/tests/operators.cc: Clang doesn't
> define __GCC_IEC_559. Use __STDC_IEC_559__ instead.
>
OK, thanks.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 2/2] libstdc++: Fix simd compilation with Clang
2023-03-21 9:23 ` [PATCH 2/2] libstdc++: Fix simd " Matthias Kretz
@ 2023-03-21 11:19 ` Jonathan Wakely
2023-03-21 17:01 ` [committed] " Matthias Kretz
0 siblings, 1 reply; 6+ messages in thread
From: Jonathan Wakely @ 2023-03-21 11:19 UTC (permalink / raw)
To: Matthias Kretz; +Cc: gcc-patches, libstdc++
[-- Attachment #1: Type: text/plain, Size: 1338 bytes --]
On Tue, 21 Mar 2023 at 09:24, Matthias Kretz via Libstdc++ <
libstdc++@gcc.gnu.org> wrote:
>
>
> Clang fails to compile some constant expressions involving simd.
> Therefore, just disable this non-conforming extension for clang.
>
> Fix AVX512 blend implementation for Clang. It was converting the bitmask
> to bool before, which is obviously wrong. Instead use a Clang builtin to
> convert the bitmask to vector-mask before using a vector blend ?:. A
> similar change is required for the masked unary implementation, because
> the GCC builtins do not exist on Clang.
>
> Signed-off-by: Matthias Kretz <m.kretz@gsi.de>
>
> libstdc++-v3/ChangeLog:
>
> * include/experimental/bits/simd_detail.h: Don't declare the
> simd API as constexpr with Clang.
> * include/experimental/bits/simd_x86.h (__movm): New.
> (_S_blend_avx512): Resolve FIXME. Implement blend using __movm
> and ?:.
> (_SimdImplX86::_S_masked_unary): Clang does not implement the
> same builtins. Implement the function using __movm, ?:, and -
> operators on vector_size types instead.
>
+#if (defined __STRICT_ANSI__ && __STRICT_ANSI__) || defined __clang__
We don't generally are about -Wundef so this could be simplified to:
#if __STRICT_ANSI__ || defined __clang__
But it's OK as it is. OK for trunk.
^ permalink raw reply [flat|nested] 6+ messages in thread
* [committed] libstdc++: Fix simd compilation with Clang
2023-03-21 11:19 ` Jonathan Wakely
@ 2023-03-21 17:01 ` Matthias Kretz
0 siblings, 0 replies; 6+ messages in thread
From: Matthias Kretz @ 2023-03-21 17:01 UTC (permalink / raw)
To: gcc-patches, libstdc++
[-- Attachment #1: Type: text/plain, Size: 1879 bytes --]
Slightly modified patch. I had to fix floating-point AVX512 blending on
Clang by removing a cast. While at it I cleaned up the -Wundef noise.
----- 8< ------
Clang fails to compile some constant expressions involving simd.
Therefore, just disable this non-conforming extension for clang.
Fix AVX512 blend implementation for Clang. It was converting the bitmask
to bool before, which is obviously wrong. Instead use a Clang builtin to
convert the bitmask to vector-mask before using a vector blend ?:. A
similar change is required for the masked unary implementation, because
the GCC builtins do not exist on Clang.
Signed-off-by: Matthias Kretz <m.kretz@gsi.de>
libstdc++-v3/ChangeLog:
* include/experimental/bits/simd_detail.h: Don't declare the
simd API as constexpr with Clang.
* include/experimental/bits/simd_x86.h (__movm): New.
(_S_blend_avx512): Resolve FIXME. Implement blend using __movm
and ?:.
(_SimdImplX86::_S_masked_unary): Clang does not implement the
same builtins. Implement the function using __movm, ?:, and -
operators on vector_size types instead.
---
.../include/experimental/bits/simd_detail.h | 2 +-
.../include/experimental/bits/simd_x86.h | 58 +++++++++++++++++--
2 files changed, 55 insertions(+), 5 deletions(-)
--
──────────────────────────────────────────────────────────────────────────
Dr. Matthias Kretz https://mattkretz.github.io
GSI Helmholtz Centre for Heavy Ion Research https://gsi.de
stdₓ::simd
──────────────────────────────────────────────────────────────────────────
[-- Attachment #2: 0001-libstdc-Fix-simd-compilation-with-Clang.patch --]
[-- Type: text/x-patch, Size: 4021 bytes --]
diff --git a/libstdc++-v3/include/experimental/bits/simd_detail.h b/libstdc++-v3/include/experimental/bits/simd_detail.h
index 30cc1ef0eef..49b94decf0a 100644
--- a/libstdc++-v3/include/experimental/bits/simd_detail.h
+++ b/libstdc++-v3/include/experimental/bits/simd_detail.h
@@ -267,7 +267,7 @@ namespace experimental
#define _GLIBCXX_SIMD_IS_UNLIKELY(__x) __builtin_expect(__x, 0)
#define _GLIBCXX_SIMD_IS_LIKELY(__x) __builtin_expect(__x, 1)
-#if defined __STRICT_ANSI__ && __STRICT_ANSI__
+#if __STRICT_ANSI__ || defined __clang__
#define _GLIBCXX_SIMD_CONSTEXPR
#define _GLIBCXX_SIMD_USE_CONSTEXPR_API const
#else
diff --git a/libstdc++-v3/include/experimental/bits/simd_x86.h b/libstdc++-v3/include/experimental/bits/simd_x86.h
index 608918542c6..7b8f1c664b3 100644
--- a/libstdc++-v3/include/experimental/bits/simd_x86.h
+++ b/libstdc++-v3/include/experimental/bits/simd_x86.h
@@ -363,6 +363,53 @@ __maskload_pd(const double* __ptr, _Tp __k)
// }}}
+#ifdef __clang__
+template <size_t _Np, typename _Tp, typename _Kp>
+ _GLIBCXX_SIMD_INTRINSIC constexpr auto
+ __movm(_Kp __k) noexcept
+ {
+ static_assert(is_unsigned_v<_Kp>);
+ if constexpr (sizeof(_Tp) == 1 && __have_avx512bw)
+ {
+ if constexpr (_Np <= 16 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2b128(__k);
+ else if constexpr (_Np <= 32 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2b256(__k);
+ else
+ return __builtin_ia32_cvtmask2b512(__k);
+ }
+ else if constexpr (sizeof(_Tp) == 2 && __have_avx512bw)
+ {
+ if constexpr (_Np <= 8 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2w128(__k);
+ else if constexpr (_Np <= 16 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2w256(__k);
+ else
+ return __builtin_ia32_cvtmask2w512(__k);
+ }
+ else if constexpr (sizeof(_Tp) == 4 && __have_avx512dq)
+ {
+ if constexpr (_Np <= 4 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2d128(__k);
+ else if constexpr (_Np <= 8 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2d256(__k);
+ else
+ return __builtin_ia32_cvtmask2d512(__k);
+ }
+ else if constexpr (sizeof(_Tp) == 8 && __have_avx512dq)
+ {
+ if constexpr (_Np <= 2 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2q128(__k);
+ else if constexpr (_Np <= 4 && __have_avx512vl)
+ return __builtin_ia32_cvtmask2q256(__k);
+ else
+ return __builtin_ia32_cvtmask2q512(__k);
+ }
+ else
+ __assert_unreachable<_Tp>();
+ }
+#endif // __clang__
+
#ifdef _GLIBCXX_SIMD_WORKAROUND_PR85048
#include "simd_x86_conversions.h"
#endif
@@ -619,14 +666,13 @@ _pdep_u32(
_GLIBCXX_SIMD_INTRINSIC static _TV
_S_blend_avx512(const _Kp __k, const _TV __a, const _TV __b) noexcept
{
-#ifdef __clang__
- // FIXME: this does a boolean choice, not a blend
- return __k ? __a : __b;
-#else
static_assert(__is_vector_type_v<_TV>);
using _Tp = typename _VectorTraits<_TV>::value_type;
static_assert(sizeof(_TV) >= 16);
static_assert(sizeof(_Tp) <= 8);
+#ifdef __clang__
+ return __movm<_VectorTraits<_TV>::_S_full_size, _Tp>(__k) ? __b : __a;
+#else
using _IntT
= conditional_t<(sizeof(_Tp) > 2),
conditional_t<sizeof(_Tp) == 4, int, long long>,
@@ -3483,6 +3529,9 @@ _S_masked_unary(const _SimdWrapper<_K, _Np> __k, const _SimdWrapper<_Tp, _Np> __
// optimize masked unary increment and decrement as masked sub +/-1
constexpr int __pm_one
= is_same_v<_Op<void>, __increment<void>> ? -1 : 1;
+#ifdef __clang__
+ return __movm<_Np, _Tp>(__k._M_data) ? __v._M_data - __pm_one : __v._M_data;
+#else // __clang__
if constexpr (is_integral_v<_Tp>)
{
constexpr bool __lp64 = sizeof(long) == sizeof(long long);
@@ -3526,6 +3575,7 @@ _S_masked_unary(const _SimdWrapper<_K, _Np> __k, const _SimdWrapper<_Tp, _Np> __
_GLIBCXX_SIMD_MASK_SUB(8, 16, subpd128);
#undef _GLIBCXX_SIMD_MASK_SUB
}
+#endif // __clang__
}
else
return _Base::template _S_masked_unary<_Op>(__k, __v);
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2023-03-21 17:01 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-03-21 9:22 [PATCH 0/2] Make std::experimental::simd (more) usable with Clang Matthias Kretz
2023-03-21 9:23 ` [PATCH 1/2] libstdc++: Fix simd test compilation " Matthias Kretz
2023-03-21 11:16 ` Jonathan Wakely
2023-03-21 9:23 ` [PATCH 2/2] libstdc++: Fix simd " Matthias Kretz
2023-03-21 11:19 ` Jonathan Wakely
2023-03-21 17:01 ` [committed] " Matthias Kretz
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