From aace6d285d7ce7434e7329a93b31c82ff2aea401 Mon Sep 17 00:00:00 2001 From: Gheorghe-Teodor Bercea Date: Wed, 19 Jun 2019 15:48:10 +0000 Subject: [PATCH] [OpenMP][libomptarget] Add support for declare target to clause under unified memory Summary: This patch adds support for handling variables under the: ``` #pragma omp declare target to() ``` clause when the ``` #pragma omp requires unified_shared_memory ``` is used. The address of the host variable is copied into the device pointer just like for the declare target link case. Reviewers: ABataev, caomhin, grokos, AlexEichenberger Reviewed By: grokos Subscribers: jcownie, guansong, jdoerfert, openmp-commits Tags: #openmp Differential Revision: https://reviews.llvm.org/D63106 llvm-svn: 363825 --- openmp/libomptarget/plugins/cuda/src/rtl.cpp | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/openmp/libomptarget/plugins/cuda/src/rtl.cpp b/openmp/libomptarget/plugins/cuda/src/rtl.cpp index 844afa107bb8..04a3ddc4002c 100644 --- a/openmp/libomptarget/plugins/cuda/src/rtl.cpp +++ b/openmp/libomptarget/plugins/cuda/src/rtl.cpp @@ -448,9 +448,18 @@ __tgt_target_table *__tgt_rtl_load_binary(int32_t device_id, DPxPTR(e - HostBegin), e->name, DPxPTR(cuptr)); entry.addr = (void *)cuptr; - if (DeviceInfo.RequiresFlags & OMP_REQ_UNIFIED_SHARED_MEMORY && - e->flags & OMP_DECLARE_TARGET_LINK) { - // If unified memory is present any target link variables + // Note: In the current implementation declare target variables + // can either be link or to. This means that once unified + // memory is activated via the requires directive, the variable + // can be used directly from the host in both cases. + // TODO: when variables types other than to or link are added, + // the below condition should be changed to explicitely + // check for to and link variables types: + // (DeviceInfo.RequiresFlags & OMP_REQ_UNIFIED_SHARED_MEMORY && + // (e->flags & OMP_DECLARE_TARGET_LINK || + // e->flags == OMP_DECLARE_TARGET_TO)) + if (DeviceInfo.RequiresFlags & OMP_REQ_UNIFIED_SHARED_MEMORY) { + // If unified memory is present any target link or to variables // can access host addresses directly. There is no longer a // need for device copies. cuMemcpyHtoD(cuptr, e->addr, sizeof(void *));