[Mlir-commits] [flang] [mlir] [Flang][mlir] - Translation of delayed privatization for deferred target-tasks (PR #155348)

[Kareem Ergawy]

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@@ -0,0 +1,484 @@
+//===- OpenMPOffloadPrivatizationPrepare.cpp - Prepare OMP privatization --===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Dialect/OpenMP/Transforms/OpenMPOffloadPrivatizationPrepare.h"
+#include "mlir/Analysis/SliceAnalysis.h"
+#include "mlir/Dialect/Func/IR/FuncOps.h"
+#include "mlir/Dialect/LLVMIR/FunctionCallUtils.h"
+#include "mlir/Dialect/LLVMIR/LLVMDialect.h"
+#include "mlir/Dialect/OpenMP/OpenMPDialect.h"
+#include "mlir/IR/Builders.h"
+#include "mlir/IR/Dominance.h"
+#include "mlir/IR/IRMapping.h"
+#include "mlir/Pass/Pass.h"
+#include "mlir/Support/LLVM.h"
+#include "llvm/Support/DebugLog.h"
+#include "llvm/Support/FormatVariadic.h"
+#include <cstdint>
+#include <iterator>
+#include <utility>
+
+//===----------------------------------------------------------------------===//
+// A pass that prepares OpenMP code for translation of delayed privatization
+// in the context of deferred target tasks. Deferred target tasks are created
+// when the nowait clause is used on the target directive.
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "omp-prepare-for-offload-privatization"
+
+namespace mlir {
+namespace omp {
+
+#define GEN_PASS_DEF_PREPAREFOROMPOFFLOADPRIVATIZATIONPASS
+#include "mlir/Dialect/OpenMP/Transforms/Passes.h.inc"
+
+} // namespace omp
+} // namespace mlir
+
+using namespace mlir;
+namespace {
+
+//===----------------------------------------------------------------------===//
+// PrepareForOMPOffloadPrivatizationPass
+//===----------------------------------------------------------------------===//
+
+class PrepareForOMPOffloadPrivatizationPass
+    : public omp::impl::PrepareForOMPOffloadPrivatizationPassBase<
+          PrepareForOMPOffloadPrivatizationPass> {
+
+  void runOnOperation() override {
+    ModuleOp mod = getOperation()->getParentOfType<ModuleOp>();
+
+    // FunctionFilteringPass removes bounds arguments from omp.map.info
+    // operations. We require bounds else our pass asserts. But, that's only for
+    // maps in functions that are on the host. So, skip functions being compiled
+    // for the target.
----------------
ergawy wrote:

IMO, this comment is a bit confusing. I think it would be better to explain that since the heap allocated memory that mirrors the privatized variables is allocated and deallocated on the host, hence, we don't need to do any modifications for the device module. Or a more general comment to the same effect without going into too much detail about what happens later.

https://github.com/llvm/llvm-project/pull/155348