Commit Graph

3 Commits

Author SHA1 Message Date
Yaxun (Sam) Liu 04caa7c3e0 [CUDA][HIP] Promote const variables to constant
Recently we added diagnosing ODR-use of host variables
in device functions, which includes ODR-use of const
host variables since they are not really emitted on
device side. This caused regressions since we used
to allow ODR-use of const host variables in device
functions.

This patch allows ODR-use of const variables in device
functions if the const variables can be statically initialized
and have an empty dtor. Such variables are marked with
implicit constant attrs and emitted on device side. This is
in line with what clang does for constexpr variables.

Reviewed by: Artem Belevich

Differential Revision: https://reviews.llvm.org/D103108
2021-06-01 21:28:41 -04:00
Yaxun (Sam) Liu 4cb42564ec [CUDA][HIP] Fix device variables used by host
variables emitted on both host and device side with different addresses
when ODR-used by host function should not cause device side counter-part
to be force emitted.

This fixes the regression caused by https://reviews.llvm.org/D102237

Reviewed by: Artem Belevich

Differential Revision: https://reviews.llvm.org/D102801
2021-05-20 17:04:29 -04:00
Yaxun (Sam) Liu 47acdec1dd [CUDA][HIP] Support accessing static device variable in host code for -fgpu-rdc
For -fgpu-rdc mode, static device vars in different TU's may have the same name.
To support accessing file-scope static device variables in host code, we need to give them
a distinct name and external linkage. This can be done by postfixing each static device variable with
a distinct CUID (Compilation Unit ID) hash.

Since the static device variables have different name across compilation units, now we let
them have external linkage so that they can be looked up by the runtime.

Reviewed by: Artem Belevich, and Jon Chesterfield

Differential Revision: https://reviews.llvm.org/D85223
2021-02-24 18:23:45 -05:00