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#include "unaligned_mem.h"
#include <library/cpp/testing/benchmark/bench.h>
#include <library/cpp/testing/unittest/registar.h>
#include <util/system/compiler.h>
#ifdef Y_HAVE_INT128
namespace {
struct TUInt128 {
bool operator==(const TUInt128& other) const {
return x == other.x;
}
ui64 Low() const {
return (ui64)x;
}
ui64 High() const {
return (ui64)(x >> 64);
}
static TUInt128 Max() {
return {~(__uint128_t)0};
}
__uint128_t x;
};
} // namespace
#endif
Y_UNIT_TEST_SUITE(UnalignedMem) {
Y_UNIT_TEST(TestReadWrite) {
alignas(ui64) char buf[100];
WriteUnaligned<ui16>(buf + 1, (ui16)1);
WriteUnaligned<ui32>(buf + 1 + 2, (ui32)2);
WriteUnaligned<ui64>(buf + 1 + 2 + 4, (ui64)3);
UNIT_ASSERT_VALUES_EQUAL(ReadUnaligned<ui16>(buf + 1), 1);
UNIT_ASSERT_VALUES_EQUAL(ReadUnaligned<ui32>(buf + 1 + 2), 2);
UNIT_ASSERT_VALUES_EQUAL(ReadUnaligned<ui64>(buf + 1 + 2 + 4), 3);
}
Y_UNIT_TEST(TestReadWriteRuntime) {
// Unlike the test above, this test avoids compile-time execution by a smart compiler.
// It is required to catch the SIGSEGV in case compiler emits an alignment-sensitive instruction.
alignas(ui64) static char buf[100] = {0}; // static is required for Clobber to work
WriteUnaligned<ui16>(buf + 1, (ui16)1);
WriteUnaligned<ui32>(buf + 1 + 2, (ui32)2);
WriteUnaligned<ui64>(buf + 1 + 2 + 4, (ui64)3);
NBench::Clobber();
auto val1 = ReadUnaligned<ui16>(buf + 1);
auto val2 = ReadUnaligned<ui32>(buf + 1 + 2);
auto val3 = ReadUnaligned<ui64>(buf + 1 + 2 + 4);
Y_DO_NOT_OPTIMIZE_AWAY(&val1);
Y_DO_NOT_OPTIMIZE_AWAY(&val2);
Y_DO_NOT_OPTIMIZE_AWAY(&val3);
Y_DO_NOT_OPTIMIZE_AWAY(val1);
Y_DO_NOT_OPTIMIZE_AWAY(val2);
Y_DO_NOT_OPTIMIZE_AWAY(val3);
UNIT_ASSERT_VALUES_EQUAL(val1, 1);
UNIT_ASSERT_VALUES_EQUAL(val2, 2);
UNIT_ASSERT_VALUES_EQUAL(val3, 3);
}
#ifdef Y_HAVE_INT128
Y_UNIT_TEST(TestReadWrite128) {
alignas(TUInt128) char buf[100] = {0};
WriteUnaligned<TUInt128>(buf + 1, TUInt128::Max());
auto val = ReadUnaligned<TUInt128>(buf + 1);
UNIT_ASSERT(val == TUInt128::Max());
}
Y_UNIT_TEST(TestReadWriteRuntime128) {
// Unlike the test above, this test avoids compile-time execution by a smart compiler.
// It is required to catch the SIGSEGV in case compiler emits an alignment-sensitive instruction.
alignas(TUInt128) static char buf[100] = {0}; // static is required for Clobber to work
WriteUnaligned<TUInt128>(buf + 1, TUInt128::Max());
NBench::Clobber();
auto val = ReadUnaligned<TUInt128>(buf + 1);
Y_DO_NOT_OPTIMIZE_AWAY(&val);
Y_DO_NOT_OPTIMIZE_AWAY(val.Low());
Y_DO_NOT_OPTIMIZE_AWAY(val.High());
UNIT_ASSERT(val == TUInt128::Max());
}
#endif
} // Y_UNIT_TEST_SUITE(UnalignedMem)
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