Tools/TestWebKitAPI/Tests/WTF/SaturatedArithmeticOperations.cpp

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#include "config.h"

#include <limits.h>
#include <wtf/SaturatedArithmetic.h>

namespace TestWebKitAPI {

TEST(WTF, SaturatedArithmeticAddition)
{
    EXPECT_EQ(0, saturatedSum<int32_t>(0, 0));
    EXPECT_EQ(1, saturatedSum<int32_t>(0, 1));
    EXPECT_EQ(100, saturatedSum<int32_t>(0, 100));
    EXPECT_EQ(150, saturatedSum<int32_t>(100, 50));

    EXPECT_EQ(-1, saturatedSum<int32_t>(0, -1));
    EXPECT_EQ(0, saturatedSum<int32_t>(1, -1));
    EXPECT_EQ(50, saturatedSum<int32_t>(100, -50));
    EXPECT_EQ(-50, saturatedSum<int32_t>(50, -100));

    EXPECT_EQ(INT_MAX - 1, saturatedSum<int32_t>(INT_MAX - 1, 0));
    EXPECT_EQ(INT_MAX, saturatedSum<int32_t>(INT_MAX - 1, 1));
    EXPECT_EQ(INT_MAX, saturatedSum<int32_t>(INT_MAX - 1, 2));
    EXPECT_EQ(INT_MAX - 1, saturatedSum<int32_t>(0, INT_MAX - 1));
    EXPECT_EQ(INT_MAX, saturatedSum<int32_t>(1, INT_MAX - 1));
    EXPECT_EQ(INT_MAX, saturatedSum<int32_t>(2, INT_MAX - 1));
    EXPECT_EQ(INT_MAX, saturatedSum<int32_t>(INT_MAX - 1, INT_MAX - 1));
    EXPECT_EQ(INT_MAX, saturatedSum<int32_t>(INT_MAX, INT_MAX));

    EXPECT_EQ(INT_MIN, saturatedSum<int32_t>(INT_MIN, 0));
    EXPECT_EQ(INT_MIN + 1, saturatedSum<int32_t>(INT_MIN + 1, 0));
    EXPECT_EQ(INT_MIN + 2, saturatedSum<int32_t>(INT_MIN + 1, 1));
    EXPECT_EQ(INT_MIN + 3, saturatedSum<int32_t>(INT_MIN + 1, 2));
    EXPECT_EQ(INT_MIN, saturatedSum<int32_t>(INT_MIN + 1, -1));
    EXPECT_EQ(INT_MIN, saturatedSum<int32_t>(INT_MIN + 1, -2));
    EXPECT_EQ(INT_MIN + 1, saturatedSum<int32_t>(0, INT_MIN + 1));
    EXPECT_EQ(INT_MIN, saturatedSum<int32_t>(-1, INT_MIN + 1));
    EXPECT_EQ(INT_MIN, saturatedSum<int32_t>(-2, INT_MIN + 1));

    EXPECT_EQ(INT_MAX / 2 + 10000, saturatedSum<int32_t>(INT_MAX / 2, 10000));
    EXPECT_EQ(INT_MAX, saturatedSum<int32_t>(INT_MAX / 2 + 1, INT_MAX / 2 + 1));
    EXPECT_EQ(-1, saturatedSum<int32_t>(INT_MIN, INT_MAX));

    EXPECT_EQ(0U, saturatedSum<uint32_t>(0U, 0U));
    EXPECT_EQ(1U, saturatedSum<uint32_t>(0U, 1U));
    EXPECT_EQ(100U, saturatedSum<uint32_t>(0U, 100U));
    EXPECT_EQ(150U, saturatedSum<uint32_t>(100U, 50U));

    EXPECT_EQ(UINT_MAX - 1, saturatedSum<uint32_t>(UINT_MAX - 1U, 0U));
    EXPECT_EQ(UINT_MAX, saturatedSum<uint32_t>(UINT_MAX - 1U, 1U));
    EXPECT_EQ(UINT_MAX, saturatedSum<uint32_t>(UINT_MAX - 1U, 2U));
    EXPECT_EQ(UINT_MAX - 1, saturatedSum<uint32_t>(0U, UINT_MAX - 1U));
    EXPECT_EQ(UINT_MAX, saturatedSum<uint32_t>(1U, UINT_MAX - 1U));
    EXPECT_EQ(UINT_MAX, saturatedSum<uint32_t>(2U, UINT_MAX - 1U));
    EXPECT_EQ(UINT_MAX, saturatedSum<uint32_t>(UINT_MAX - 1U, UINT_MAX - 1U));
    EXPECT_EQ(UINT_MAX, saturatedSum<uint32_t>(UINT_MAX, UINT_MAX));

    EXPECT_EQ(UINT_MAX / 2 + 10000, saturatedSum<uint32_t>(UINT_MAX / 2U, 10000U));
    EXPECT_EQ(UINT_MAX, saturatedSum<uint32_t>(UINT_MAX / 2U, UINT_MAX / 2U + 1U));
    EXPECT_EQ(UINT_MAX, saturatedSum<uint32_t>(UINT_MAX / 2U + 1U, UINT_MAX / 2U + 1U));
    EXPECT_EQ(UINT_MAX, saturatedSum<uint32_t>(UINT_MAX / 3U + 1U, UINT_MAX / 3U, UINT_MAX / 3U));
    EXPECT_EQ(UINT_MAX, saturatedSum<uint32_t>(UINT_MAX / 3U + 1U, UINT_MAX / 3U + 1U, UINT_MAX / 3U + 1U));
}

TEST(WTF, SaturatedArithmeticSubtraction)
{
    EXPECT_EQ(0, saturatedDifference<int32_t>(0, 0));
    EXPECT_EQ(-1, saturatedDifference<int32_t>(0, 1));
    EXPECT_EQ(-100, saturatedDifference<int32_t>(0, 100));
    EXPECT_EQ(50, saturatedDifference<int32_t>(100, 50));
    
    EXPECT_EQ(1, saturatedDifference<int32_t>(0, -1));
    EXPECT_EQ(2, saturatedDifference<int32_t>(1, -1));
    EXPECT_EQ(150, saturatedDifference<int32_t>(100, -50));
    EXPECT_EQ(150, saturatedDifference<int32_t>(50, -100));

    EXPECT_EQ(INT_MAX, saturatedDifference<int32_t>(INT_MAX, 0));
    EXPECT_EQ(INT_MAX - 1, saturatedDifference<int32_t>(INT_MAX, 1));
    EXPECT_EQ(INT_MAX - 1, saturatedDifference<int32_t>(INT_MAX - 1, 0));
    EXPECT_EQ(INT_MAX, saturatedDifference<int32_t>(INT_MAX - 1, -1));
    EXPECT_EQ(INT_MAX, saturatedDifference<int32_t>(INT_MAX - 1, -2));
    EXPECT_EQ(-INT_MAX + 1, saturatedDifference<int32_t>(0, INT_MAX - 1));
    EXPECT_EQ(-INT_MAX, saturatedDifference<int32_t>(-1, INT_MAX - 1));
    EXPECT_EQ(-INT_MAX - 1, saturatedDifference<int32_t>(-2, INT_MAX - 1));
    EXPECT_EQ(-INT_MAX - 1, saturatedDifference<int32_t>(-3, INT_MAX - 1));

    EXPECT_EQ(INT_MIN, saturatedDifference<int32_t>(INT_MIN, 0));
    EXPECT_EQ(INT_MIN + 1, saturatedDifference<int32_t>(INT_MIN + 1, 0));
    EXPECT_EQ(INT_MIN, saturatedDifference<int32_t>(INT_MIN + 1, 1));
    EXPECT_EQ(INT_MIN, saturatedDifference<int32_t>(INT_MIN + 1, 2));

    EXPECT_EQ(0, saturatedDifference<int32_t>(INT_MIN, INT_MIN));
    EXPECT_EQ(0, saturatedDifference<int32_t>(INT_MAX, INT_MAX));
    EXPECT_EQ(INT_MAX, saturatedDifference<int32_t>(INT_MAX, INT_MIN));
}

} // namespace TestWebKitAPI