[Mlir-commits] [mlir] [MLIR][MPI] Add LLVM lowering patterns for some MPI operations (PR #95524)

[Markus Böck]

================
@@ -0,0 +1,230 @@
+//===- MPIToLLVM.cpp - MPI to LLVM dialect conversion ---------------------===//
+//
+// 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/Conversion/MPIToLLVM/MPIToLLVM.h"
+
+#include "mlir/Conversion/LLVMCommon/Pattern.h"
+#include "mlir/Dialect/LLVMIR/LLVMDialect.h"
+#include "mlir/Dialect/MPI/IR/MPI.h"
+#include "mlir/Pass/Pass.h"
+
+#include <mlir/Conversion/ConvertToLLVM/ToLLVMInterface.h>
+
+using namespace mlir;
+
+namespace {
+
+struct InitOpLowering : ConvertOpToLLVMPattern<mpi::InitOp> {
+  using ConvertOpToLLVMPattern::ConvertOpToLLVMPattern;
+
+  LogicalResult
+  matchAndRewrite(mpi::InitOp op, OpAdaptor adaptor,
+                  ConversionPatternRewriter &rewriter) const override;
+};
+
+struct CommRankOpLowering : ConvertOpToLLVMPattern<mpi::CommRankOp> {
+  using ConvertOpToLLVMPattern::ConvertOpToLLVMPattern;
+
+  LogicalResult
+  matchAndRewrite(mpi::CommRankOp op, OpAdaptor adaptor,
+                  ConversionPatternRewriter &rewriter) const override;
+};
+
+struct FinalizeOpLowering : ConvertOpToLLVMPattern<mpi::FinalizeOp> {
+  using ConvertOpToLLVMPattern::ConvertOpToLLVMPattern;
+
+  LogicalResult
+  matchAndRewrite(mpi::FinalizeOp op, OpAdaptor adaptor,
+                  ConversionPatternRewriter &rewriter) const override;
+};
+
+// TODO: this was copied from GPUOpsLowering.cpp:288
+// is this okay, or should this be moved to some common file?
+LLVM::LLVMFuncOp getOrDefineFunction(ModuleOp &moduleOp, const Location loc,
+                                     ConversionPatternRewriter &rewriter,
+                                     StringRef name,
+                                     LLVM::LLVMFunctionType type) {
+  LLVM::LLVMFuncOp ret;
+  if (!(ret = moduleOp.lookupSymbol<LLVM::LLVMFuncOp>(name))) {
+    ConversionPatternRewriter::InsertionGuard guard(rewriter);
+    rewriter.setInsertionPointToStart(moduleOp.getBody());
+    ret = rewriter.create<LLVM::LLVMFuncOp>(loc, name, type,
+                                            LLVM::Linkage::External);
+  }
+  return ret;
+}
+
+// TODO: this is pretty close to getOrDefineFunction, can probably be factored
+LLVM::GlobalOp getOrDefineExternalStruct(ModuleOp &moduleOp, const Location loc,
+                                         ConversionPatternRewriter &rewriter,
+                                         StringRef name,
+                                         LLVM::LLVMStructType type) {
+  LLVM::GlobalOp ret;
+  if (!(ret = moduleOp.lookupSymbol<LLVM::GlobalOp>(name))) {
+    ConversionPatternRewriter::InsertionGuard guard(rewriter);
+    rewriter.setInsertionPointToStart(moduleOp.getBody());
+    ret = rewriter.create<LLVM::GlobalOp>(
+        loc, type, /*isConstant=*/false, LLVM::Linkage::External, name,
+        /*value=*/Attribute(), /*alignment=*/0, 0);
+  }
+  return ret;
+}
+
+} // namespace
+
+//===----------------------------------------------------------------------===//
+// InitOpLowering
+//===----------------------------------------------------------------------===//
+
+LogicalResult
+InitOpLowering::matchAndRewrite(mpi::InitOp op, OpAdaptor adaptor,
+                                ConversionPatternRewriter &rewriter) const {
+  // get loc
+  auto loc = op.getLoc();
----------------
zero9178 wrote:

```suggestion
  Location loc = op.getLoc();
```
Ditto in other places where the type of the variable does not appear in the right-hand side expression

https://github.com/llvm/llvm-project/pull/95524