[Mlir-commits] [mlir] [mlir][mpi] Lowering Mpi To LLVM (PR #127053)

[Christian Ulmann]

================
@@ -0,0 +1,521 @@
+//===- 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
+//
+//===----------------------------------------------------------------------===//
+
+//
+// Copyright (C) by Argonne National Laboratory
+//    See COPYRIGHT in top-level directory
+//    of MPICH source repository.
+//
+
+#include "mlir/Conversion/MPIToLLVM/MPIToLLVM.h"
+#include "mlir/Conversion/ConvertToLLVM/ToLLVMInterface.h"
+#include "mlir/Conversion/LLVMCommon/Pattern.h"
+#include "mlir/Dialect/DLTI/DLTI.h"
+#include "mlir/Dialect/LLVMIR/LLVMDialect.h"
+#include "mlir/Dialect/MPI/IR/MPI.h"
+#include "mlir/Transforms/DialectConversion.h"
+
+using namespace mlir;
+
+namespace {
+
+template <typename Op, typename... Args>
+static Op getOrDefineGlobal(mlir::ModuleOp &moduleOp, const Location loc,
+                            ConversionPatternRewriter &rewriter, StringRef name,
+                            Args &&...args) {
+  Op ret;
+  if (!(ret = moduleOp.lookupSymbol<Op>(name))) {
+    ConversionPatternRewriter::InsertionGuard guard(rewriter);
+    rewriter.setInsertionPointToStart(moduleOp.getBody());
+    ret = rewriter.template create<Op>(loc, std::forward<Args>(args)...);
+  }
+  return ret;
+}
+
+static LLVM::LLVMFuncOp getOrDefineFunction(ModuleOp &moduleOp,
+                                            const Location loc,
+                                            ConversionPatternRewriter &rewriter,
+                                            StringRef name,
+                                            LLVM::LLVMFunctionType type) {
+  return getOrDefineGlobal<LLVM::LLVMFuncOp>(
+      moduleOp, loc, rewriter, name, name, type, LLVM::Linkage::External);
+}
+
+//===----------------------------------------------------------------------===//
+// Implementation details for MPICH ABI compatible MPI implementations
+//===----------------------------------------------------------------------===//
+struct MPICHImplTraits {
+  static const int MPI_FLOAT = 0x4c00040a;
----------------
Dinistro wrote:

```suggestion
  static constexpr int MPI_FLOAT = 0x4c00040a;
```

https://github.com/llvm/llvm-project/pull/127053