[Mlir-commits] [mlir] Add a polynomial dialect shell, attributes, and types (PR #72081)

[Oleksandr Alex Zinenko]

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@@ -0,0 +1,217 @@
+//===- PolynomialAttributes.cpp - Polynomial dialect attributes --*- 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
+//
+//===----------------------------------------------------------------------===//
+#include "mlir/Dialect/Polynomial/IR/PolynomialAttributes.h"
+
+#include "mlir/Dialect/Polynomial/IR/Polynomial.h"
+#include "mlir/Support/LLVM.h"
+#include "mlir/Support/LogicalResult.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/StringRef.h"
+
+namespace mlir {
+namespace polynomial {
+
+void PolynomialAttr::print(AsmPrinter &p) const {
+  p << '<';
+  p << getPolynomial();
+  p << '>';
+}
+
+/// Try to parse a monomial. If successful, populate the fields of the outparam
+/// `monomial` with the results, and the `variable` outparam with the parsed
+/// variable name.
+ParseResult parseMonomial(AsmParser &parser, Monomial &monomial,
+                          llvm::StringRef *variable, bool *isConstantTerm) {
+  APInt parsedCoeff(apintBitWidth, 1);
+  auto result = parser.parseOptionalInteger(parsedCoeff);
+  if (result.has_value()) {
+    if (failed(*result)) {
+      parser.emitError(parser.getCurrentLocation(),
+                       "Invalid integer coefficient.");
+      return failure();
+    }
+  }
+
+  // Variable name
+  result = parser.parseOptionalKeyword(variable);
+  if (!result.has_value() || failed(*result)) {
----------------
ftynse wrote:

I'm not sure I understand the syntax here. Maybe adding tests, or pasting examples, could help. There's no lookahead exposed at this level of the API.

One specific thing that looks tricky here: if parser returns failure as opposed to nullopt, it means it may have reported an error diagnostic to the user, and it will be very surprising if the parsing procedure actually succeeds after that. It may not be the case right now, though.

https://github.com/llvm/llvm-project/pull/72081