[OpenMP] NVPTX: Set default/minimum compute capability to sm_35

The current implementation of the nvptx runtime (to be upstreamed shortly) uses the atomicMax operation on 64-bit integers.
This is only supported in compute capabilities 3.5 and later. I've changed the clang default to sm_35.

Differential Revision: https://reviews.llvm.org/D40977

llvm-svn: 320082
This commit is contained in:
George Rokos 2017-12-07 20:27:31 +00:00
parent dfc79c7c33
commit 145c54721b
1 changed files with 7 additions and 6 deletions

View File

@ -241,14 +241,15 @@ set(CLANG_DEFAULT_OBJCOPY "objcopy" CACHE STRING
set(CLANG_DEFAULT_OPENMP_RUNTIME "libomp" CACHE STRING
"Default OpenMP runtime used by -fopenmp.")
# OpenMP offloading requires at least sm_30 because we use shuffle instructions
# to generate efficient code for reductions.
set(CLANG_OPENMP_NVPTX_DEFAULT_ARCH "sm_30" CACHE STRING
# OpenMP offloading requires at least sm_35 because we use shuffle instructions
# to generate efficient code for reductions and the atomicMax instruction on
# 64-bit integers in the implementation of conditional lastprivate.
set(CLANG_OPENMP_NVPTX_DEFAULT_ARCH "sm_35" CACHE STRING
"Default architecture for OpenMP offloading to Nvidia GPUs.")
string(REGEX MATCH "^sm_([0-9]+)$" MATCHED_ARCH "${CLANG_OPENMP_NVPTX_DEFAULT_ARCH}")
if (NOT DEFINED MATCHED_ARCH OR "${CMAKE_MATCH_1}" LESS 30)
message(WARNING "Resetting default architecture for OpenMP offloading to Nvidia GPUs to sm_30")
set(CLANG_OPENMP_NVPTX_DEFAULT_ARCH "sm_30" CACHE STRING
if (NOT DEFINED MATCHED_ARCH OR "${CMAKE_MATCH_1}" LESS 35)
message(WARNING "Resetting default architecture for OpenMP offloading to Nvidia GPUs to sm_35")
set(CLANG_OPENMP_NVPTX_DEFAULT_ARCH "sm_35" CACHE STRING
"Default architecture for OpenMP offloading to Nvidia GPUs." FORCE)
endif()