[Openmp-commits] [PATCH] D76713: [libomptarget][nfc] Explicitly static function scope shared variables

[Jon Chesterfield via Phabricator via Openmp-commits]

JonChesterfield created this revision.
JonChesterfield added reviewers: jdoerfert, ABataev, grokos.
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[libomptarget][nfc] Explicitly static function scope shared variables

`__shared__` in CUDA implies static in function scope. See e.g. D.2.1.1
in CUDA_C_Programming_Guide.pdf,
http://developer.download.nvidia.com/compute/DevZone/docs/html/C/doc/

This is surprising for non-cuda developers, see e.g. D73239 <https://reviews.llvm.org/D73239> where I thought
local variables would be thread local.

Tested by IR diff of libomptarget.bc (no change), running in tree tests,
and binary diff of the nvcc static archives (no significant change).


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D76713

Files:
  openmp/libomptarget/deviceRTLs/common/src/reduction.cu


Index: openmp/libomptarget/deviceRTLs/common/src/reduction.cu
===================================================================
--- openmp/libomptarget/deviceRTLs/common/src/reduction.cu
+++ openmp/libomptarget/deviceRTLs/common/src/reduction.cu
@@ -230,7 +230,7 @@
                           : /*Master thread only*/ 1;
   uint32_t TeamId = GetBlockIdInKernel();
   uint32_t NumTeams = GetNumberOfBlocksInKernel();
-  SHARED volatile bool IsLastTeam;
+  static SHARED volatile bool IsLastTeam;
 
   // Team masters of all teams write to the scratchpad.
   if (ThreadId == 0) {
@@ -423,8 +423,8 @@
                          : /*Master thread only*/ 1;
   uint32_t TeamId = GetBlockIdInKernel();
   uint32_t NumTeams = GetNumberOfBlocksInKernel();
-  SHARED unsigned Bound;
-  SHARED unsigned ChunkTeamCount;
+  static SHARED unsigned Bound;
+  static SHARED unsigned ChunkTeamCount;
 
   // Block progress for teams greater than the current upper
   // limit. We always only allow a number of teams less or equal


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