From e9a55b7c48d5fa09d405ac413b11e1ea850ce2bb Mon Sep 17 00:00:00 2001 From: George Rokos Date: Thu, 7 Dec 2017 20:27:31 +0000 Subject: [PATCH] [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 git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@320082 91177308-0d34-0410-b5e6-96231b3b80d8 --- CMakeLists.txt | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/CMakeLists.txt b/CMakeLists.txt index 8848798515..2eee8e6148 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -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() -- 2.40.0