68 lines
2.1 KiB
C++
68 lines
2.1 KiB
C++
//===- LinearTransform.cpp - MLIR LinearTransform Class -------------------===//
|
|
//
|
|
// 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/LinearTransform.h"
|
|
#include "mlir/Analysis/Presburger/IntegerRelation.h"
|
|
|
|
using namespace mlir;
|
|
using namespace presburger;
|
|
|
|
LinearTransform::LinearTransform(Matrix &&oMatrix) : matrix(oMatrix) {}
|
|
LinearTransform::LinearTransform(const Matrix &oMatrix) : matrix(oMatrix) {}
|
|
|
|
std::pair<unsigned, LinearTransform>
|
|
LinearTransform::makeTransformToColumnEchelon(const Matrix &m) {
|
|
// Compute the hermite normal form of m. This, is by definition, is in column
|
|
// echelon form.
|
|
auto [h, u] = m.computeHermiteNormalForm();
|
|
|
|
// Since the matrix is in column ecehlon form, a zero column means the rest of
|
|
// the columns are zero. Thus, once we find a zero column, we can stop.
|
|
unsigned col, e;
|
|
for (col = 0, e = m.getNumColumns(); col < e; ++col) {
|
|
bool zeroCol = true;
|
|
for (unsigned row = 0, f = m.getNumRows(); row < f; ++row) {
|
|
if (h(row, col) != 0) {
|
|
zeroCol = false;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (zeroCol)
|
|
break;
|
|
}
|
|
|
|
return {col, LinearTransform(std::move(u))};
|
|
}
|
|
|
|
IntegerRelation LinearTransform::applyTo(const IntegerRelation &rel) const {
|
|
IntegerRelation result(rel.getSpace());
|
|
|
|
for (unsigned i = 0, e = rel.getNumEqualities(); i < e; ++i) {
|
|
ArrayRef<MPInt> eq = rel.getEquality(i);
|
|
|
|
const MPInt &c = eq.back();
|
|
|
|
SmallVector<MPInt, 8> newEq = preMultiplyWithRow(eq.drop_back());
|
|
newEq.push_back(c);
|
|
result.addEquality(newEq);
|
|
}
|
|
|
|
for (unsigned i = 0, e = rel.getNumInequalities(); i < e; ++i) {
|
|
ArrayRef<MPInt> ineq = rel.getInequality(i);
|
|
|
|
const MPInt &c = ineq.back();
|
|
|
|
SmallVector<MPInt, 8> newIneq = preMultiplyWithRow(ineq.drop_back());
|
|
newIneq.push_back(c);
|
|
result.addInequality(newIneq);
|
|
}
|
|
|
|
return result;
|
|
}
|