llvm/unittests/ADT/IntEqClassesTest.cpp

//===---- ADT/IntEqClassesTest.cpp - IntEqClasses unit tests ----*- 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 "llvm/ADT/IntEqClasses.h"
#include "gtest/gtest.h"

using namespace llvm;

namespace {

TEST(IntEqClasses, Simple) {
  IntEqClasses ec(10);

  ec.join(0, 1);
  ec.join(3, 2);
  ec.join(4, 5);
  ec.join(7, 6);

  EXPECT_EQ(0u, ec.findLeader(0));
  EXPECT_EQ(0u, ec.findLeader(1));
  EXPECT_EQ(2u, ec.findLeader(2));
  EXPECT_EQ(2u, ec.findLeader(3));
  EXPECT_EQ(4u, ec.findLeader(4));
  EXPECT_EQ(4u, ec.findLeader(5));
  EXPECT_EQ(6u, ec.findLeader(6));
  EXPECT_EQ(6u, ec.findLeader(7));
  EXPECT_EQ(8u, ec.findLeader(8));
  EXPECT_EQ(9u, ec.findLeader(9));

  // join two non-leaders.
  ec.join(1, 3);

  EXPECT_EQ(0u, ec.findLeader(0));
  EXPECT_EQ(0u, ec.findLeader(1));
  EXPECT_EQ(0u, ec.findLeader(2));
  EXPECT_EQ(0u, ec.findLeader(3));
  EXPECT_EQ(4u, ec.findLeader(4));
  EXPECT_EQ(4u, ec.findLeader(5));
  EXPECT_EQ(6u, ec.findLeader(6));
  EXPECT_EQ(6u, ec.findLeader(7));
  EXPECT_EQ(8u, ec.findLeader(8));
  EXPECT_EQ(9u, ec.findLeader(9));

  // join two leaders.
  ec.join(4, 8);

  EXPECT_EQ(0u, ec.findLeader(0));
  EXPECT_EQ(0u, ec.findLeader(1));
  EXPECT_EQ(0u, ec.findLeader(2));
  EXPECT_EQ(0u, ec.findLeader(3));
  EXPECT_EQ(4u, ec.findLeader(4));
  EXPECT_EQ(4u, ec.findLeader(5));
  EXPECT_EQ(6u, ec.findLeader(6));
  EXPECT_EQ(6u, ec.findLeader(7));
  EXPECT_EQ(4u, ec.findLeader(8));
  EXPECT_EQ(9u, ec.findLeader(9));

  // join mixed.
  ec.join(9, 1);

  EXPECT_EQ(0u, ec.findLeader(0));
  EXPECT_EQ(0u, ec.findLeader(1));
  EXPECT_EQ(0u, ec.findLeader(2));
  EXPECT_EQ(0u, ec.findLeader(3));
  EXPECT_EQ(4u, ec.findLeader(4));
  EXPECT_EQ(4u, ec.findLeader(5));
  EXPECT_EQ(6u, ec.findLeader(6));
  EXPECT_EQ(6u, ec.findLeader(7));
  EXPECT_EQ(4u, ec.findLeader(8));
  EXPECT_EQ(0u, ec.findLeader(9));

  // compressed map.
  ec.compress();
  EXPECT_EQ(3u, ec.getNumClasses());

  EXPECT_EQ(0u, ec[0]);
  EXPECT_EQ(0u, ec[1]);
  EXPECT_EQ(0u, ec[2]);
  EXPECT_EQ(0u, ec[3]);
  EXPECT_EQ(1u, ec[4]);
  EXPECT_EQ(1u, ec[5]);
  EXPECT_EQ(2u, ec[6]);
  EXPECT_EQ(2u, ec[7]);
  EXPECT_EQ(1u, ec[8]);
  EXPECT_EQ(0u, ec[9]);

  // uncompressed map.
  ec.uncompress();
  EXPECT_EQ(0u, ec.findLeader(0));
  EXPECT_EQ(0u, ec.findLeader(1));
  EXPECT_EQ(0u, ec.findLeader(2));
  EXPECT_EQ(0u, ec.findLeader(3));
  EXPECT_EQ(4u, ec.findLeader(4));
  EXPECT_EQ(4u, ec.findLeader(5));
  EXPECT_EQ(6u, ec.findLeader(6));
  EXPECT_EQ(6u, ec.findLeader(7));
  EXPECT_EQ(4u, ec.findLeader(8));
  EXPECT_EQ(0u, ec.findLeader(9));
}

} // end anonymous namespace