This patch is part of the upstreaming effort for supporting SYCL
language front end.
It makes the following changes:
1. Adds sycl_external attribute for functions with external linkage,
which is intended for use to implement the SYCL_EXTERNAL macro as
specified by the SYCL 2020 specification
2. Adds checks to avoid emitting device code when sycl_external and
sycl_kernel_entry_point attributes are not enabled
3. Fixes test failures caused by the above changes
This patch is missing diagnostics for the following diagnostics listed
in the SYCL 2020 specification's section 5.10.1, which will be addressed
in a subsequent PR:
Functions that are declared using SYCL_EXTERNAL have the following
additional restrictions beyond those imposed on other device functions:
1. If the SYCL backend does not support the generic address space then
the function cannot use raw pointers as parameter or return types.
Explicit pointer classes must be used instead;
2. The function cannot call group::parallel_for_work_item;
3. The function cannot be called from a parallel_for_work_group scope.
In addition to that, the subsequent PR will also implement diagnostics
for inline functions including virtual functions defined as inline.
---------
Co-authored-by: Mariya Podchishchaeva <mariya.podchishchaeva@intel.com>
Like CUDA and OpenCL, the SYCL specification says that throwing and
catching exceptions in device functions is not supported, so this change
extends the logic for adding the NoUnwind attribute to SYCL.
The existing convergent.cpp test, which tests that the convergent
attribute is added to functions by default, is renamed and reused to
test that the nounwind attribute is added by default. This test now has
-fexceptions added to it, which the driver adds by default as well.
The obvious question here is why not simply change the driver to remove
-fexceptions. This change follows the direction given by the TODO
comment because removing -fexceptions would also disable the
__EXCEPTIONS macro, which should reflect whether exceptions are enabled
on the host, rather than on the device, to avoid conflicts in types
shared between host and device.
Reviewed By: bader
Differential Revision: https://reviews.llvm.org/D147097
