Some functions and subroutines are available in device context
(device/global). These functions have interfaces declared in the
`cudadevice` module.
This patch adds interfaces as `__cuda_device_builtins_<fctname>` in a
builtin module and they are USE'd rename in the `cudadevice` module. The
module is implicitly used in device/global subprograms.
The builtin module only contains procedures from section 3.6.4 for now.
…Warn()
Many warning messages were being emitted unconditionally. Ensure that
all warnings are conditional on a true result from a call to
common::LanguageFeatureControl::ShouldWarn() so that it is easy for a
driver to disable them all, or, in the future, to provide per-warning
control over them.
In the presence of other semantic error, `GetAssignment` would return a
nullptr and therefore would make the rest of the check crash when trying
to collect symbols.
Exiting early when we have a nullptr so the compiler doesn't crash and
user can get the meaningful semantic error.
The specification allow list-directed PRINT and WRITE statements to
appear in device code. This patch relax the semantic check to allow
them.
3.6.11.
List-directed PRINT and WRITE statements to the default unit may be used
when compiling for compute capability 2.0 and higher; all other uses of
PRINT and WRITE are disallowed.
In section 3.4.2, some example of illegal data transfer using expression
are given. One of it is when multiple device objects are part of an
expression in the rhs. Current implementation allow a single device
object in such case. This patch adds a similar restriction.
