[llvm] [mlir] [mlir][EmitC] Add Arith to EmitC conversions (PR #84151)

[Matthias Gehre via llvm-commits]

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@@ -0,0 +1,59 @@
+//===- ArithToEmitC.cpp - Arith to EmitC Patterns ---------------*- C++ -*-===//
+//
+// 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 patterns to convert the Arith dialect to the EmitC
+// dialect.
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Conversion/ArithToEmitC/ArithToEmitC.h"
+
+#include "mlir/Dialect/Arith/IR/Arith.h"
+#include "mlir/Dialect/EmitC/IR/EmitC.h"
+#include "mlir/Transforms/DialectConversion.h"
+
+using namespace mlir;
+
+//===----------------------------------------------------------------------===//
+// Conversion Patterns
+//===----------------------------------------------------------------------===//
+
+namespace {
+template <typename ArithOp, typename EmitCOp>
+class ArithOpConversion final : public OpConversionPattern<ArithOp> {
+public:
+  using OpConversionPattern<ArithOp>::OpConversionPattern;
+
+  LogicalResult
+  matchAndRewrite(ArithOp arithOp, typename ArithOp::Adaptor adaptor,
+                  ConversionPatternRewriter &rewriter) const override {
+
+    rewriter.template replaceOpWithNewOp<EmitCOp>(arithOp, arithOp.getType(),
+                                                  adaptor.getOperands());
+
+    return success();
+  }
+};
+} // namespace
+
+//===----------------------------------------------------------------------===//
+// Pattern population
+//===----------------------------------------------------------------------===//
+
+void mlir::populateArithToEmitCPatterns(RewritePatternSet &patterns) {
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mgehre-amd wrote:

Can this please take an additional `TypeConverter &converter` argument which is passed to patterns.add below? It will then allow to compose these patterns with a type converter, e.g. to have a custom legalization of types like `i3` or similar in downstream projects.

https://github.com/llvm/llvm-project/pull/84151