[flang-commits] [flang] [llvm] [mlir] [MLIR][OpenMP] Lowering nontemporal clause to LLVM IR for SIMD directive (PR #118751)

[Kaviya Rajendiran via flang-commits]

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@@ -0,0 +1,82 @@
+//===- LowerNontemporal.cpp -------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Add nontemporal attributes to load and stores of variables marked as
+// nontemporal.
+//
+//===----------------------------------------------------------------------===//
+
+#include "flang/Optimizer/Dialect/FIRCG/CGOps.h"
+#include "flang/Optimizer/Dialect/FIROpsSupport.h"
+#include "flang/Optimizer/OpenMP/Passes.h"
+#include "mlir/Dialect/OpenMP/OpenMPDialect.h"
+#include "llvm/ADT/TypeSwitch.h"
+
+using namespace mlir;
+
+namespace flangomp {
+#define GEN_PASS_DEF_LOWERNONTEMPORALPASS
+#include "flang/Optimizer/OpenMP/Passes.h.inc"
+} // namespace flangomp
+
+namespace {
+class LowerNontemporalPass
+    : public flangomp::impl::LowerNontemporalPassBase<LowerNontemporalPass> {
+  void addNonTemporalAttr(omp::SimdOp simdOp) {
+    if (simdOp.getNontemporalVars().empty())
+      return;
+
+    std::function<mlir::Value(mlir::Value)> getBaseOperand =
+        [&](mlir::Value operand) -> mlir::Value {
+      auto *defOp = operand.getDefiningOp();
+      while (defOp) {
+        llvm::TypeSwitch<Operation *>(defOp)
+            .Case<fir::ArrayCoorOp, fir::cg::XArrayCoorOp, fir::LoadOp>(
+                [&](auto op) {
+                  operand = op.getMemref();
+                  defOp = operand.getDefiningOp();
+                })
+            .Case<fir::BoxAddrOp>([&](auto op) {
+              operand = op.getVal();
+              defOp = operand.getDefiningOp();
+            })
+            .Default([&](auto op) { defOp = nullptr; });
+      }
+      return operand;
+    };
+
+    // walk through the operations and mark the load and store as nontemporal
+    simdOp->walk([&](Operation *op) {
+      mlir::Value operand = nullptr;
+
+      if (auto loadOp = llvm::dyn_cast<fir::LoadOp>(op))
+        operand = loadOp.getMemref();
+      else if (auto storeOp = llvm::dyn_cast<fir::StoreOp>(op))
+        operand = storeOp.getMemref();
+
+      if (operand && !(fir::isAllocatableType(operand.getType()) ||
+                       fir::isPointerType((operand.getType())))) {
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kaviya2510 wrote:

Thanks for the comments.
Sure, I will add a comment for the same.

https://github.com/llvm/llvm-project/pull/118751