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// Copyright Epic Games, Inc. All Rights Reserved.

#include <zencore/intmath.h>

#include <doctest/doctest.h>

namespace zen {

//////////////////////////////////////////////////////////////////////////
//
// Testing related code follows...
//

void
intmath_forcelink()
{
}

TEST_CASE("intmath")
{
	CHECK(FloorLog2(0x00) == 0);
	CHECK(FloorLog2(0x01) == 0);
	CHECK(FloorLog2(0x0f) == 3);
	CHECK(FloorLog2(0x10) == 4);
	CHECK(FloorLog2(0x11) == 4);
	CHECK(FloorLog2(0x12) == 4);
	CHECK(FloorLog2(0x22) == 5);
	CHECK(FloorLog2(0x0001'0000) == 16);
	CHECK(FloorLog2(0x0001'000f) == 16);
	CHECK(FloorLog2(0x8000'0000) == 31);

	CHECK(FloorLog2_64(0x00ull) == 0);
	CHECK(FloorLog2_64(0x01ull) == 0);
	CHECK(FloorLog2_64(0x0full) == 3);
	CHECK(FloorLog2_64(0x10ull) == 4);
	CHECK(FloorLog2_64(0x11ull) == 4);
	CHECK(FloorLog2_64(0x0001'0000ull) == 16);
	CHECK(FloorLog2_64(0x0001'000full) == 16);
	CHECK(FloorLog2_64(0x8000'0000ull) == 31);
	CHECK(FloorLog2_64(0x0000'0001'0000'0000ull) == 32);
	CHECK(FloorLog2_64(0x8000'0000'0000'0000ull) == 63);

	CHECK(CountLeadingZeros64(0x8000'0000'0000'0000ull) == 0);
	CHECK(CountLeadingZeros64(0x0000'0000'0000'0000ull) == 64);
	CHECK(CountLeadingZeros64(0x0000'0000'0000'0001ull) == 63);
	CHECK(CountLeadingZeros64(0x0000'0000'8000'0000ull) == 32);
	CHECK(CountLeadingZeros64(0x0000'0001'0000'0000ull) == 31);

	CHECK(CountTrailingZeros64(0x8000'0000'0000'0000ull) == 63);
	CHECK(CountTrailingZeros64(0x0000'0000'0000'0000ull) == 64);
	CHECK(CountTrailingZeros64(0x0000'0000'0000'0001ull) == 0);
	CHECK(CountTrailingZeros64(0x0000'0000'8000'0000ull) == 31);
	CHECK(CountTrailingZeros64(0x0000'0001'0000'0000ull) == 32);
}

} // namespace zen