[OpenMP][libomptarget] Initialize global memory stack only once.
Summary: The global stack initialization function may be called multiple times. The initialization of the shared memory slots should only happen when the function is called for the first time for a given warp master thread.
Reviewers: grokos, carlo.bertolli, ABataev, caomhin
Reviewed By: grokos
Subscribers: guansong, openmp-commits
Differential Revision: https://reviews.llvm.org/D44754
git-svn-id: https://llvm.org/svn/llvm-project/openmp/trunk@328148 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/libomptarget/deviceRTLs/nvptx/src/data_sharing.cu b/libomptarget/deviceRTLs/nvptx/src/data_sharing.cu
index e0256d3..8340c08 100644
--- a/libomptarget/deviceRTLs/nvptx/src/data_sharing.cu
+++ b/libomptarget/deviceRTLs/nvptx/src/data_sharing.cu
@@ -346,9 +346,14 @@
&omptarget_nvptx_threadPrivateContext->TeamContext();
__kmpc_data_sharing_slot *RootS = teamDescr->RootS(WID, IsMasterThread());
- DataSharingState.SlotPtr[WID] = RootS;
- DataSharingState.TailPtr[WID] = RootS;
- DataSharingState.StackPtr[WID] = (void *)&RootS->Data[0];
+ // If a valid address has been returned then proceed with the initalization.
+ // Otherwise the initialization of the slot has already happened in a
+ // previous call to this function.
+ if (RootS) {
+ DataSharingState.SlotPtr[WID] = RootS;
+ DataSharingState.TailPtr[WID] = RootS;
+ DataSharingState.StackPtr[WID] = (void *)&RootS->Data[0];
+ }
}
// Currently we only support the sharing of variables between master and
diff --git a/libomptarget/deviceRTLs/nvptx/src/omptarget-nvptx.h b/libomptarget/deviceRTLs/nvptx/src/omptarget-nvptx.h
index 1902861..1d063c3 100644
--- a/libomptarget/deviceRTLs/nvptx/src/omptarget-nvptx.h
+++ b/libomptarget/deviceRTLs/nvptx/src/omptarget-nvptx.h
@@ -263,6 +263,9 @@
// If this is invoked by the master thread of the master warp then intialize
// it with a smaller slot.
if (IsMasterThread) {
+ // Do not initalize this slot again if it has already been initalized.
+ if (master_rootS[0].DataEnd == &master_rootS[0].Data[0] + DS_Slot_Size)
+ return 0;
// Initialize the pointer to the end of the slot given the size of the
// data section. DataEnd is non-inclusive.
master_rootS[0].DataEnd = &master_rootS[0].Data[0] + DS_Slot_Size;
@@ -272,6 +275,10 @@
master_rootS[0].PrevSlotStackPtr = 0;
return (__kmpc_data_sharing_slot *)&master_rootS[0];
}
+ // Do not initalize this slot again if it has already been initalized.
+ if (worker_rootS[wid].DataEnd ==
+ &worker_rootS[wid].Data[0] + DS_Worker_Warp_Slot_Size)
+ return 0;
// Initialize the pointer to the end of the slot given the size of the data
// section. DataEnd is non-inclusive.
worker_rootS[wid].DataEnd =
