CUDA-9.2 made all integer SIMD functions into compiler builtins,
so clang no longer has access to the implementation of these
functions in either headers of libdevice and has to provide
its own implementation.
This is mostly a 1:1 mapping to a corresponding PTX instructions
with an exception of vhadd2/vhadd4 that don't have an equivalent
instruction and had to be implemented with a bit hack.
Performance of this implementation will be suboptimal for SM_50
and newer GPUs where PTXAS generates noticeably worse code for
the SIMD instructions compared to the code it generates
for the inline assembly generated by nvcc (or used to come
with CUDA headers).
Differential Revision: https://reviews.llvm.org/D49274
llvm-svn: 337587
Initial commit missed sincos(float), llabs() and few atomics that we
used to pull in from device_functions.hpp, which we no longer include.
Differential Revision: https://reviews.llvm.org/D43602
llvm-svn: 325814
Clang can use CUDA-9.1 now, though new APIs (are not implemented yet.
The major change is that headers in CUDA-9.1 went through substantial
changes that started in CUDA-9.0 which required substantial changes
in the cuda compatibility headers provided by clang.
There are two major issues:
* CUDA SDK no longer provides declarations for libdevice functions.
* A lot of device-side functions have become nvcc's builtins and
CUDA headers no longer contain their implementations.
This patch changes the way CUDA headers are handled if we compile
with CUDA 9.x. Both 9.0 and 9.1 are affected.
* Clang provides its own declarations of libdevice functions.
* For CUDA-9.x clang now provides implementation of device-side
'standard library' functions using libdevice.
This patch should not affect compilation with CUDA-8. There may be
some observable differences for CUDA-9.0, though they are not expected
to affect functionality.
Tested: CUDA test-suite tests for all supported combinations of:
CUDA: 7.0,7.5,8.0,9.0,9.1
GPU: sm_20, sm_35, sm_60, sm_70
Differential Revision: https://reviews.llvm.org/D42513
llvm-svn: 323713