[Mlir-commits] [mlir] [MLIR][Presburger] Generating functions and quasi-polynomials for Barvinok's algorithm (PR #75702)

[Arjun P]

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+//===- QuasiPolynomial.cpp - Quasipolynomial Class --------------*- 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/Analysis/Presburger/QuasiPolynomial.h"
+#include "mlir/Analysis/Presburger/Fraction.h"
+#include "mlir/Analysis/Presburger/IntegerRelation.h"
+#include "mlir/Analysis/Presburger/Matrix.h"
+#include "mlir/Analysis/Presburger/PresburgerSpace.h"
+#include "mlir/Analysis/Presburger/Utils.h"
+#include "mlir/Support/LogicalResult.h"
+#include <optional>
+
+using namespace mlir;
+using namespace presburger;
+
+QuasiPolynomial::QuasiPolynomial(
+    unsigned numParam, SmallVector<Fraction> coeffs,
+    std::vector<std::vector<SmallVector<Fraction>>> aff)
+    : numParam(numParam), coefficients(coeffs), affine(aff) {
+  // Find the first term which involves some affine function.
+  for (const std::vector<SmallVector<Fraction>> &term : affine) {
+    if (term.size() == 0)
+      continue;
+    // The number of elements in each affine function is
+    // one more than the number of parameters.
+    for (const SmallVector<Fraction> &aff : term) {
+      assert(aff.size() - 1 == numParam &&
----------------
Superty wrote:

(as per the c++ standard, the code is still correct as low as long as numParams is not INT_MAX so we don't have to be concerned about the tests. but it's better to not depend on the specification of underflows unnecessarily.)

https://github.com/llvm/llvm-project/pull/75702