Using GCC 9.2 the pre change vtkm::filter::Threshold would
take 31.84sec to compile and use 1.1GB of memory. After
these changes the filter takes 24.16sec to compile and
uses 885MB of memory.
CMake 3.16 includes support for unity builds which merge multiple
translation units together automatically for faster builds.
A couple of translation units in VTK-m already require lots of
system memory, and merging them actually decreases compile performance
There is some behavior of GCC compilers before GCC 9.0 that is
incompatible with the specification of OpenMP 4.0. The workaround was
using the workaround any time a GCC compiler >= 9.0 was used. The proper
behavior is to only use the workaround when the GCC compiler is being
used and the version of the compiler is less than 9.0.
Also, switch to using VTKM_GCC to check for the GCC compiler instead of
__GNUC__. The problem with using __GNUC__ is that many other compilers
pretend to be GCC by defining this macro, but in cases like compiler
workarounds it is not accurate.
Older GCC compilers were giving warnings in the operator of the
GeneratePoints worklets for tubes because they could not completely
determine that variables were being properly initialized in the first
loop iteration (and therefore initialized for every subsequent
iteration). Fixed that by moving the initialization for the first
iteration outside of the loop.
Previously we relied on CMake's compiler detection module to build the
macros for using the deprecated attribute. However, CMake created macros
for pre-C++14 versions of the feature, which do not work in all cases.
Also, we have the need to be able to suppress deprecation warnings when
we are implementing a deprecated thing. Since we have to query compilers
ourself, we might as well figure out if the deprecated attribute we want
is supported.
Worst case is that we won't support deprecation warnings everywhere we
could. That will not create incorrect code and we can always add that
later.
Previously, Configure.h.in used a pragma to disable warning 4996 is all
VTK-m code and anything that used it. The reason for this was that the
warning was given for any use of std algorithms such as fill_n that the
Visual Studio team deemed unsafe. Although we could fix it in our code,
it was impossible to work around warnings in other headers as the actual
warning comes from a system header file (xutility) that we have very
little control over. At the time we disabled this warning, we were
getting the warning from a bost header file, and the warning was never
to be fixed (https://svn.boost.org/trac/boost/ticket/11426).
Unfortunately, disabling warning 4996 also disables all warnings about
deprecated items. We want to support warnings for things deprecated in
VTK-m itself, so turning off this warning means we cannot correctly
support VTK-m deprecation.
Fortunately, a lot has changed since then. We no longer boost at all, so
the issue there is no longer our problem. We can thus re-enable the
warning (by removing the pragma). We've managed to avoid using these
"unsafe" functions anyway, so we should be able to cleanly build with
this warning on.
The `VTKM_DEPRECATED` macro allows us to remove (and usually replace)
features from VTK-m in minor releases while still following the conventions
of semantic versioning. The idea is that when we want to remove or replace
a feature, we first mark the old feature as deprecated. The old feature
will continue to work, but compilers that support it will start to issue a
warning that the use is deprecated and should stop being used. The
deprecated features should remain viable until at least the next major
version. At the next major version, deprecated features from the previous
version may be removed.
Previously when ApplyPolicyFieldOfType was used in cases where not all
of the types matched not all of the storages, those invalid arrays were
replaced with an ArrayHandleDiscard. This unnecessarily increased the
length of the type names used for the resulting ArrayHandleMultiplexer.
Now, ListTagRemoveIf is used to remove any invalid arrays so that the
resulting ArrayHandleMultiplexer only includes the valid arrays.
3b7b21c86 Do not use std::is_trivially_copyable on GCC 4.X
Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: Robert Maynard <robert.maynard@kitware.com>
Merge-request: !1900
Although GCC 4.8 and 4.9 claim to be C++11 compliant, there are a few
C++11 features they do not support. One of these features is
std::is_trivially_copyable. So on these platforms, do not attempt to use
it. Instead, treat nothing as trivially copyable.
7518d0675 Try to fix uninitialized anonymous variable warning
5b18ffd77 Register Variant as trivially copyable if possible
16305bd83 Add tests of ArrayHandleMultiplexer on multiple devices
Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: Robert Maynard <robert.maynard@kitware.com>
Merge-request: !1898
The code from the previous commit was causing one of the dashboards,
which is using gcc-7, to produce the following warning:
In file included from ../testing/UnitTestVariant.cxx:11:0:
../Variant.h: In function 'void {anonymous}::TestCopyDestroy()':
../Variant.h:269:5: warning: '<anonymous>' may be used uninitialized in this function [-Wmaybe-uninitialized]
this->Storage = std::move(rhs.Storage);
^~~~
At best, this warning is not helpful as it does not seem to point to
anything that could be used uninitialized. At worst, it might be a
compiler bug. A Google search finds a few similar bugs although none I
can assert with any confidence of this issue. However, many reported
bugs and issues point to the use of anonymous namespaces. So, I'm going
to attempt to fix the problem by removing anonymous namespaces.
Hopefully it will fix the warning or at least point me to something
concrete that I can fix.
The Variant template can hold any type. If it is holding a type that is
non-copyable, then it has to make sure that appropriate constructors,
copiers, movers, and destructors are called.
Previously, these were called even the Variant was holding a trivially
copyable class because no harm no foul. If you were holding a trivially
copyable class and did a memcpy, that work work, which should make it
possible to copy between host and device, right?
In theory yes, but in practice no. The problem is that Cuda is
outsmarting the code. It is checking that Variant is not trivially-
copyable by C++ semantics and refusing to push it.
So, change Variant to check to see if all its supported classes are
trivially copyable. If they are, then it use the default constructors,
destructors, movers, and copiers so that C++ recognizes it as trivially
copyable.