[clang] [flang] [llvm] [openmp] [OpenMP][Offload] Add offload runtime support for dyn_groupprivate clause (PR #152831)

[Kevin Sala Penades via cfe-commits]

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@@ -515,8 +524,60 @@ Error GenericKernelTy::launch(GenericDeviceTy &GenericDevice, void **ArgPtrs,
   llvm::SmallVector<void *, 16> Args;
   llvm::SmallVector<void *, 16> Ptrs;
 
+  uint32_t NumThreads[3] = {KernelArgs.ThreadLimit[0],
+                            KernelArgs.ThreadLimit[1],
+                            KernelArgs.ThreadLimit[2]};
+  uint32_t NumBlocks[3] = {KernelArgs.NumTeams[0], KernelArgs.NumTeams[1],
+                           KernelArgs.NumTeams[2]};
+  if (!isBareMode()) {
+    NumThreads[0] = getNumThreads(GenericDevice, NumThreads);
+    NumBlocks[0] = getNumBlocks(GenericDevice, NumBlocks, KernelArgs.Tripcount,
+                                NumThreads[0], KernelArgs.ThreadLimit[0] > 0);
+  }
+
+  uint32_t MaxBlockMemSize = GenericDevice.getMaxBlockSharedMemSize();
+  uint32_t DynBlockMemSize = KernelArgs.DynCGroupMem;
+  uint32_t TotalBlockMemSize = StaticBlockMemSize + DynBlockMemSize;
+  if (StaticBlockMemSize > MaxBlockMemSize)
+    return Plugin::error(ErrorCode::INVALID_ARGUMENT,
+                         "Static block memory size exceeds maximum");
+  else if (static_cast<DynCGroupMemFallbackType>(
+               KernelArgs.Flags.DynCGroupMemFallback) ==
+               DynCGroupMemFallbackType::Abort &&
+           TotalBlockMemSize > MaxBlockMemSize)
+    return Plugin::error(
+        ErrorCode::INVALID_ARGUMENT,
+        "Static and dynamic block memory size exceeds maximum");
+
+  void *DynBlockMemFbPtr = nullptr;
+  uint32_t DynBlockMemLaunchSize = DynBlockMemSize;
+
+  DynCGroupMemFallbackType DynBlockMemFb = DynCGroupMemFallbackType::None;
+  if (DynBlockMemSize && (!GenericDevice.hasNativeBlockSharedMem() ||
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kevinsala wrote:

For case a), the developers of such a feature should account for that amount of dynamic shared memory (effectively reducing the amount available for the OpenMP user).

https://github.com/llvm/llvm-project/pull/152831