reinterpret_cast between unrelated types is undefined behavior and leads
to misoptimizations on some platforms.
Use the safer (and faster) version via bit_cast
These names are so common, IMO they should not exist directly in the
`Eigen::` namespace. This prevents us from using the `last` or `all`
names for any parameters or local variables, otherwise spitting out
warnings about shadowing or hiding the global values. Many external
projects (and our own examples) also heavily use
```
using namespace Eigen;
```
which means these conflict with external libraries as well, e.g.
`std::fill(first,last,value)`.
It seems originally these were placed in a separate namespace
`Eigen::placeholders`, which has since been deprecated. I propose
to un-deprecate this, and restore the original locations.
These symbols are also imported into `Eigen::indexing`, which
additionally imports `fix` and `seq`. An alternative is to remove the
`placeholders` namespace and stick with `indexing`.
NOTE: this is an API-breaking change.
Fixes#2321.
An analogue of `std::tuple` that works on device.
Context: I've tried `std::tuple` in various versions of NVCC and clang,
and although code seems to compile, it often fails to run - generating
"illegal memory access" errors, or "illegal instruction" errors.
This replacement does work on device.
The `Serializer<T>` class implements a binary serialization that
can write to (`serialize`) and read from (`deserialize`) a byte
buffer. Also added convenience routines for serializing
a list of arguments.
This will mainly be for testing, specifically to transfer data to
and from the GPU.
The `Options` of the new `hCoeffs` vector do not necessarily match
those of the `MatrixType`, leading to build errors. Having the
`CoeffVectorType` be a template parameter relieves this restriction.
CUDA 9 seems to require labelling defaulted constructors as
`EIGEN_DEVICE_FUNC`, despite giving warnings that such labels are
ignored. Without these labels, the `gpu_basic` test fails to
compile, with errors about calling `__host__` functions from
`__host__ __device__` functions.
GCC 4.8 doesn't seem to like the `g` register constraint, failing to
compile with "error: 'asm' operand requires impossible reload".
Tested `r` instead, and that seems to work, even with latest compilers.
Also fixed some minor macro issues to eliminate warnings on armv7.
Fixes#2315.
All cuda `__half` functions are device-only in CUDA 9, including
conversions. Host-side conversions were added in CUDA 10.
The existing code doesn't build prior to 10.0.
All arithmetic functions are always device-only, so there's
therefore no reason to use vectorization on the host at all.
Modified the code to disable vectorization for `__half` on host,
which required also updating the `TensorReductionGpu` implementation
which previously made assumptions about available packets.
There were some typos that checked `EIGEN_HAS_CXX14` that should have
checked `EIGEN_HAS_CXX14_VARIABLE_TEMPLATES`, causing a mismatch
in some of the `Eigen::fix<N>` assumptions.
Also fixed the `symbolic_index` test when
`EIGEN_HAS_CXX14_VARIABLE_TEMPLATES` is 0.
Fixes#2308
In VS 2017, `std::arg` for real inputs always returns 0, even for
negative inputs. It should return `PI` for negative real values.
This seems to be fixed in VS 2019 (MSVC 1920).
There seems to be a gcc 4.7 bug that incorrectly flags the current
3x3 inverse as using uninitialized memory. I'm *pretty* sure it's
a false positive, but it's hard to trigger. The same warning
does not trigger with clang or later compiler versions.
In trying to find a work-around, this implementation turns out to be
faster anyways for static-sized matrices.
```
name old cpu/op new cpu/op delta
BM_Inverse3x3<DynamicMatrix3T<float>> 423ns ± 2% 433ns ± 3% +2.32% (p=0.000 n=98+96)
BM_Inverse3x3<DynamicMatrix3T<double>> 425ns ± 2% 427ns ± 3% +0.48% (p=0.003 n=99+96)
BM_Inverse3x3<StaticMatrix3T<float>> 7.10ns ± 2% 0.80ns ± 1% -88.67% (p=0.000 n=114+112)
BM_Inverse3x3<StaticMatrix3T<double>> 7.45ns ± 2% 1.34ns ± 1% -82.01% (p=0.000 n=105+111)
BM_AliasedInverse3x3<DynamicMatrix3T<float>> 409ns ± 3% 419ns ± 3% +2.40% (p=0.000 n=100+98)
BM_AliasedInverse3x3<DynamicMatrix3T<double>> 414ns ± 3% 413ns ± 2% ~ (p=0.322 n=98+98)
BM_AliasedInverse3x3<StaticMatrix3T<float>> 7.57ns ± 1% 0.80ns ± 1% -89.37% (p=0.000 n=111+114)
BM_AliasedInverse3x3<StaticMatrix3T<double>> 9.09ns ± 1% 2.58ns ±41% -71.60% (p=0.000 n=113+116)
```
The `memset` function and bitwise manipulation only apply to POD types
that do not require initialization, otherwise resulting in UB. We currently
violate this in `ptrue` and `pzero`, we assume bitmasks for `pselect`, and
bitwise operations are applied byte-by-byte in the generic implementations.
This is causing issues for scalar types that do require initialization
or that contain non-POD info such as pointers (#2201). We either break
them, or force specializations of these functions for custom scalars,
even if they are not vectorized.
Here we modify these functions for scalars only - instead using only
scalar operations:
- `pzero`: `Scalar(0)` for all scalars.
- `ptrue`: `Scalar(1)` for non-trivial scalars, bitset to one bits for trivial scalars.
- `pselect`: ternary select comparing mask to `Scalar(0)` for all scalars
- `pand`, `por`, `pxor`, `pnot`: use operators `&`, `|`, `^`, `~` for all integer or non-trivial scalars, otherwise apply bytewise.
For non-scalar types, the original implementations are used to maintain
compatibility and minimize the number of changes.
Fixes#2201.
Since `std::equal_to::operator()` is not a device function, it
fails on GPU. On my device, I seem to get a silent crash in the
kernel (no reported error, but the kernel does not complete).
Replacing this with a portable version enables comparisons on device.
Addresses #2292 - would need to be cherry-picked. The 3.3 branch
also requires adding `EIGEN_DEVICE_FUNC` in `BooleanRedux.h` to get
fully working.
Details are scattered across #920, #1000, #1324, #2291.
Summary: some MSVC versions have a bug that requires omitting explicit
`operator=` definitions (leads to duplicate definition errors), and
some MSVC versions require adding explicit `operator=` definitions
(otherwise implicitly deleted errors). This mess tries to cover
all the cases encountered.
Fixes#2291.