[clang] [CIR] Add TargetLowering pass (PR #179245)

[Sirui Mu via cfe-commits]

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@@ -0,0 +1,80 @@
+//===- TargetLowering.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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the cir-target-lowering pass.
+//
+//===----------------------------------------------------------------------===//
+
+#include "TargetLowering/LowerModule.h"
+
+#include "mlir/Support/LLVM.h"
+#include "clang/CIR/Dialect/Passes.h"
+#include "llvm/ADT/TypeSwitch.h"
+
+using namespace mlir;
+using namespace cir;
+
+namespace mlir {
+#define GEN_PASS_DEF_TARGETLOWERING
+#include "clang/CIR/Dialect/Passes.h.inc"
+} // namespace mlir
+
+namespace {
+
+struct TargetLoweringPass
+    : public impl::TargetLoweringBase<TargetLoweringPass> {
+  TargetLoweringPass() = default;
+  void runOnOperation() override;
+
+private:
+  void runOnOp(cir::LoadOp op, cir::LowerModule &lowerModule);
+  void runOnOp(cir::StoreOp op, cir::LowerModule &lowerModule);
+};
+
+} // namespace
+
+static void convertSyncScopeIfPresent(mlir::Operation *op,
+                                      cir::LowerModule &lowerModule) {
+  auto syncScopeAttr =
+      mlir::cast_if_present<cir::SyncScopeKindAttr>(op->getAttr("sync_scope"));
+  if (syncScopeAttr) {
+    cir::SyncScopeKind convertedSyncScope =
+        lowerModule.getTargetLoweringInfo().convertSyncScope(
+            syncScopeAttr.getValue());
+    op->setAttr("sync_scope", cir::SyncScopeKindAttr::get(op->getContext(),
+                                                          convertedSyncScope));
+  }
+}
+
+void TargetLoweringPass::runOnOp(cir::LoadOp op,
+                                 cir::LowerModule &lowerModule) {
+  convertSyncScopeIfPresent(op, lowerModule);
+}
+
+void TargetLoweringPass::runOnOp(cir::StoreOp op,
+                                 cir::LowerModule &lowerModule) {
+  convertSyncScopeIfPresent(op, lowerModule);
+}
+
+void TargetLoweringPass::runOnOperation() {
+  auto mod = mlir::cast<mlir::ModuleOp>(getOperation());
+  auto lowerModule = cir::createLowerModule(mod);
+  // If lower module is not available, skip the target lowering pass.
+  if (!lowerModule)
----------------
Lancern wrote:

Updated.

The `CXXABILowering` pass also has a fragment of similar code. It is updated, too.

https://github.com/llvm/llvm-project/pull/179245