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ARROW-10058: [C++] Improve repeated levels conversion without BMI2 #8320

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ARROW-10058: [C++] Improve repeated levels conversion without BMI2 #8320

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57 changes: 8 additions & 49 deletions cpp/src/parquet/level_conversion.cc
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Original file line number Diff line number Diff line change
Expand Up @@ -36,41 +36,6 @@ namespace {

using ::arrow::internal::CpuInfo;

void DefLevelsToBitmapScalar(const int16_t* def_levels, int64_t num_def_levels,
LevelInfo level_info, ValidityBitmapInputOutput* output) {
::arrow::internal::FirstTimeBitmapWriter valid_bits_writer(
output->valid_bits,
/*start_offset=*/output->valid_bits_offset,
/*length=*/num_def_levels);
for (int x = 0; x < num_def_levels; x++) {
// This indicates that a parent repeated element has zero
// length so the def level is not applicable to this column.
if (def_levels[x] < level_info.repeated_ancestor_def_level) {
continue;
}
if (ARROW_PREDICT_FALSE(valid_bits_writer.position() >=
output->values_read_upper_bound)) {
std::stringstream ss;
ss << "Definition levels exceeded upper bound: " << output->values_read_upper_bound;
throw ParquetException(ss.str());
}
if (def_levels[x] >= level_info.def_level) {
valid_bits_writer.Set();
} else {
valid_bits_writer.Clear();
output->null_count += 1;
}
valid_bits_writer.Next();
}
valid_bits_writer.Finish();
output->values_read = valid_bits_writer.position();
if (output->null_count > 0 && level_info.null_slot_usage > 1) {
throw ParquetException(
"Null values with null_slot_usage > 1 not supported."
"(i.e. FixedSizeLists with null values are not supported");
}
}

template <typename OffsetType>
void DefRepLevelsToListInfo(const int16_t* def_levels, const int16_t* rep_levels,
int64_t num_def_levels, LevelInfo level_info,
Expand Down Expand Up @@ -170,27 +135,21 @@ void DefLevelsToBitmap(const int16_t* def_levels, int64_t num_def_levels,
// is deleted in a follow-up release.
if (level_info.rep_level > 0) {
#if defined(ARROW_HAVE_RUNTIME_BMI2)
using FunctionType = decltype(&standard::DefLevelsToBitmapSimd<true>);
// DefLevelsToBitmapSimd with emulated PEXT would be slow, so use the
// scalar version if BMI2 is unavailable.
static FunctionType fn = CpuInfo::GetInstance()->HasEfficientBmi2()
? DefLevelsToBitmapBmi2WithRepeatedParent
: DefLevelsToBitmapScalar;
fn(def_levels, num_def_levels, level_info, output);
#else
DefLevelsToBitmapScalar(def_levels, num_def_levels, level_info, output);
if (CpuInfo::GetInstance()->HasEfficientBmi2()) {
return DefLevelsToBitmapBmi2WithRepeatedParent(def_levels, num_def_levels,
level_info, output);
}
#endif
standard::DefLevelsToBitmapSimd</*has_repeated_parent=*/true>(
def_levels, num_def_levels, level_info, output);
} else {
// SIMD here applies to all platforms because the only operation that
// happens is def_levels->bitmap which should have good SIMD options
// on all platforms.
standard::DefLevelsToBitmapSimd</*has_repeated_parent=*/false>(
def_levels, num_def_levels, level_info, output);
}
}

uint64_t TestOnlyRunBasedExtract(uint64_t bitmap, uint64_t select_bitmap) {
return standard::RunBasedExtractImpl(bitmap, select_bitmap);
uint64_t TestOnlyExtractBitsSoftware(uint64_t bitmap, uint64_t select_bitmap) {
return standard::ExtractBitsSoftware(bitmap, select_bitmap);
}

void DefRepLevelsToList(const int16_t* def_levels, const int16_t* rep_levels,
Expand Down
2 changes: 1 addition & 1 deletion cpp/src/parquet/level_conversion.h
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Original file line number Diff line number Diff line change
Expand Up @@ -192,7 +192,7 @@ void PARQUET_EXPORT DefRepLevelsToBitmap(const int16_t* def_levels,

// This is exposed to ensure we can properly test a software simulated pext function
// (i.e. it isn't hidden by runtime dispatch).
uint64_t PARQUET_EXPORT TestOnlyRunBasedExtract(uint64_t bitmap, uint64_t selection);
uint64_t PARQUET_EXPORT TestOnlyExtractBitsSoftware(uint64_t bitmap, uint64_t selection);

} // namespace internal
} // namespace parquet
242 changes: 216 additions & 26 deletions cpp/src/parquet/level_conversion_inc.h
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Original file line number Diff line number Diff line change
Expand Up @@ -35,44 +35,234 @@ namespace internal {
#endif
namespace PARQUET_IMPL_NAMESPACE {

/// Algorithm to simulate pext using BitRunReader for cases where all bits
/// not set or set.
uint64_t RunBasedExtractMixed(uint64_t bitmap, uint64_t select_bitmap) {
bitmap = arrow::BitUtil::FromLittleEndian(bitmap);
uint64_t new_bitmap = 0;
::arrow::internal::BitRunReader selection(reinterpret_cast<uint8_t*>(&select_bitmap),
/*start_offset=*/0, /*length=*/64);
::arrow::internal::BitRun run = selection.NextRun();
int64_t selected_bits = 0;
while (run.length != 0) {
if (run.set) {
new_bitmap |= (bitmap & ::arrow::BitUtil::LeastSignficantBitMask(run.length))
<< selected_bits;
selected_bits += run.length;
}
bitmap = bitmap >> run.length;
run = selection.NextRun();
}
return arrow::BitUtil::ToLittleEndian(new_bitmap);
}
// clang-format off
/* Python code to generate lookup table:

kLookupBits = 5
count = 0
print('constexpr int kLookupBits = {};'.format(kLookupBits))
print('constexpr uint8_t kPextTable[1 << kLookupBits][1 << kLookupBits] = {')
print(' ', end = '')
for mask in range(1 << kLookupBits):
for data in range(1 << kLookupBits):
bit_value = 0
bit_len = 0
for i in range(kLookupBits):
if mask & (1 << i):
bit_value |= (((data >> i) & 1) << bit_len)
bit_len += 1
out = '0x{:02X},'.format(bit_value)
count += 1
if count % (1 << kLookupBits) == 1:
print(' {')
if count % 8 == 1:
print(' ', end = '')
if count % 8 == 0:
print(out, end = '\n')
else:
print(out, end = ' ')
if count % (1 << kLookupBits) == 0:
print(' },', end = '')
print('\n};')

*/
// clang-format on

inline uint64_t RunBasedExtractImpl(uint64_t bitmap, uint64_t select_bitmap) {
/// These checks should be inline and are likely to be common cases.
constexpr int kLookupBits = 5;
constexpr uint8_t kPextTable[1 << kLookupBits][1 << kLookupBits] = {
{
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
},
{
0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01,
0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01,
},
{
0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01,
0x01, 0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01, 0x01, 0x00, 0x00,
0x01, 0x01, 0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01, 0x01,
},
{
0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x02,
0x03, 0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x02, 0x03, 0x00, 0x01,
0x02, 0x03, 0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x02, 0x03,
},
{
0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00, 0x00,
0x00, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01,
0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x01,
},
{
0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x02, 0x03, 0x00, 0x01, 0x00,
0x01, 0x02, 0x03, 0x02, 0x03, 0x00, 0x01, 0x00, 0x01, 0x02, 0x03,
0x02, 0x03, 0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x02, 0x03,
},
{
0x00, 0x00, 0x01, 0x01, 0x02, 0x02, 0x03, 0x03, 0x00, 0x00, 0x01,
0x01, 0x02, 0x02, 0x03, 0x03, 0x00, 0x00, 0x01, 0x01, 0x02, 0x02,
0x03, 0x03, 0x00, 0x00, 0x01, 0x01, 0x02, 0x02, 0x03, 0x03,
},
{
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x00, 0x01, 0x02,
0x03, 0x04, 0x05, 0x06, 0x07, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05,
0x06, 0x07, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
},
{
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01,
0x01, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
},
{
0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x02,
0x03, 0x02, 0x03, 0x02, 0x03, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01,
0x00, 0x01, 0x02, 0x03, 0x02, 0x03, 0x02, 0x03, 0x02, 0x03,
},
{
0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01, 0x01, 0x02, 0x02, 0x03,
0x03, 0x02, 0x02, 0x03, 0x03, 0x00, 0x00, 0x01, 0x01, 0x00, 0x00,
0x01, 0x01, 0x02, 0x02, 0x03, 0x03, 0x02, 0x02, 0x03, 0x03,
},
{
0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
0x07, 0x04, 0x05, 0x06, 0x07, 0x00, 0x01, 0x02, 0x03, 0x00, 0x01,
0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x04, 0x05, 0x06, 0x07,
},
{
0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x01, 0x02, 0x02, 0x02,
0x02, 0x03, 0x03, 0x03, 0x03, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01,
0x01, 0x01, 0x02, 0x02, 0x02, 0x02, 0x03, 0x03, 0x03, 0x03,
},
{
0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x02, 0x03, 0x04, 0x05, 0x04,
0x05, 0x06, 0x07, 0x06, 0x07, 0x00, 0x01, 0x00, 0x01, 0x02, 0x03,
0x02, 0x03, 0x04, 0x05, 0x04, 0x05, 0x06, 0x07, 0x06, 0x07,
},
{
0x00, 0x00, 0x01, 0x01, 0x02, 0x02, 0x03, 0x03, 0x04, 0x04, 0x05,
0x05, 0x06, 0x06, 0x07, 0x07, 0x00, 0x00, 0x01, 0x01, 0x02, 0x02,
0x03, 0x03, 0x04, 0x04, 0x05, 0x05, 0x06, 0x06, 0x07, 0x07,
},
{
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A,
0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05,
0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
},
{
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
},
{
0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
0x01, 0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x02, 0x03, 0x02, 0x03,
0x02, 0x03, 0x02, 0x03, 0x02, 0x03, 0x02, 0x03, 0x02, 0x03,
},
{
0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01,
0x01, 0x00, 0x00, 0x01, 0x01, 0x02, 0x02, 0x03, 0x03, 0x02, 0x02,
0x03, 0x03, 0x02, 0x02, 0x03, 0x03, 0x02, 0x02, 0x03, 0x03,
},
{
0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x02,
0x03, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x04, 0x05,
0x06, 0x07, 0x04, 0x05, 0x06, 0x07, 0x04, 0x05, 0x06, 0x07,
},
{
0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00, 0x00,
0x00, 0x01, 0x01, 0x01, 0x01, 0x02, 0x02, 0x02, 0x02, 0x03, 0x03,
0x03, 0x03, 0x02, 0x02, 0x02, 0x02, 0x03, 0x03, 0x03, 0x03,
},
{
0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x02, 0x03, 0x00, 0x01, 0x00,
0x01, 0x02, 0x03, 0x02, 0x03, 0x04, 0x05, 0x04, 0x05, 0x06, 0x07,
0x06, 0x07, 0x04, 0x05, 0x04, 0x05, 0x06, 0x07, 0x06, 0x07,
},
{
0x00, 0x00, 0x01, 0x01, 0x02, 0x02, 0x03, 0x03, 0x00, 0x00, 0x01,
0x01, 0x02, 0x02, 0x03, 0x03, 0x04, 0x04, 0x05, 0x05, 0x06, 0x06,
0x07, 0x07, 0x04, 0x04, 0x05, 0x05, 0x06, 0x06, 0x07, 0x07,
},
{
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x00, 0x01, 0x02,
0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D,
0x0E, 0x0F, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
},
{
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01,
0x01, 0x01, 0x01, 0x01, 0x01, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02,
0x02, 0x02, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03,
},
{
0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x02,
0x03, 0x02, 0x03, 0x02, 0x03, 0x04, 0x05, 0x04, 0x05, 0x04, 0x05,
0x04, 0x05, 0x06, 0x07, 0x06, 0x07, 0x06, 0x07, 0x06, 0x07,
},
{
0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01, 0x01, 0x02, 0x02, 0x03,
0x03, 0x02, 0x02, 0x03, 0x03, 0x04, 0x04, 0x05, 0x05, 0x04, 0x04,
0x05, 0x05, 0x06, 0x06, 0x07, 0x07, 0x06, 0x06, 0x07, 0x07,
},
{
0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
0x07, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x08, 0x09,
0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x0C, 0x0D, 0x0E, 0x0F,
},
{
0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x01, 0x02, 0x02, 0x02,
0x02, 0x03, 0x03, 0x03, 0x03, 0x04, 0x04, 0x04, 0x04, 0x05, 0x05,
0x05, 0x05, 0x06, 0x06, 0x06, 0x06, 0x07, 0x07, 0x07, 0x07,
},
{
0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x02, 0x03, 0x04, 0x05, 0x04,
0x05, 0x06, 0x07, 0x06, 0x07, 0x08, 0x09, 0x08, 0x09, 0x0A, 0x0B,
0x0A, 0x0B, 0x0C, 0x0D, 0x0C, 0x0D, 0x0E, 0x0F, 0x0E, 0x0F,
},
{
0x00, 0x00, 0x01, 0x01, 0x02, 0x02, 0x03, 0x03, 0x04, 0x04, 0x05,
0x05, 0x06, 0x06, 0x07, 0x07, 0x08, 0x08, 0x09, 0x09, 0x0A, 0x0A,
0x0B, 0x0B, 0x0C, 0x0C, 0x0D, 0x0D, 0x0E, 0x0E, 0x0F, 0x0F,
},
{
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A,
0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15,
0x16, 0x17, 0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F,
},
};

inline uint64_t ExtractBitsSoftware(uint64_t bitmap, uint64_t select_bitmap) {
// A software emulation of _pext_u64

// These checks should be inline and are likely to be common cases.
if (select_bitmap == ~uint64_t{0}) {
return bitmap;
} else if (select_bitmap == 0) {
return 0;
}
/// Fallback to the slow method.
return RunBasedExtractMixed(bitmap, select_bitmap);

// Fallback to lookup table method
uint64_t bit_value = 0;
int bit_len = 0;
constexpr uint8_t kLookupMask = (1U << kLookupBits) - 1;
while (select_bitmap != 0) {
const auto mask_len = ARROW_POPCOUNT32(select_bitmap & kLookupMask);
const uint64_t value = kPextTable[select_bitmap & kLookupMask][bitmap & kLookupMask];
bit_value |= (value << bit_len);
bit_len += mask_len;
bitmap >>= kLookupBits;
select_bitmap >>= kLookupBits;
}
return bit_value;
}

inline uint64_t ExtractBits(uint64_t bitmap, uint64_t select_bitmap) {
// MING32 doesn't support 64-bit pext.
// MING32 doesn't support 64-bit pext.
#if defined(ARROW_HAVE_BMI2) && !defined(__MINGW32__)
return _pext_u64(bitmap, select_bitmap);
#else
return RunBasedExtractImpl(bitmap, select_bitmap);
return ExtractBitsSoftware(bitmap, select_bitmap);
#endif
}

Expand Down
24 changes: 10 additions & 14 deletions cpp/src/parquet/level_conversion_test.cc
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -345,20 +345,16 @@ TYPED_TEST(NestedListTest, TestOverflow) {
this->Run(test_data, level_info);
}

TEST(TestOnlyRunBasedExtract, BasicTest) {
EXPECT_EQ(TestOnlyRunBasedExtract(arrow::BitUtil::ToLittleEndian(0xFF), 0), 0);
EXPECT_EQ(TestOnlyRunBasedExtract(arrow::BitUtil::ToLittleEndian(0xFF), ~uint64_t{0}),
arrow::BitUtil::ToLittleEndian(0xFF));

EXPECT_EQ(TestOnlyRunBasedExtract(arrow::BitUtil::ToLittleEndian(0xFF00FF),
arrow::BitUtil::ToLittleEndian(0xAAAA)),
arrow::BitUtil::ToLittleEndian(0x000F));
EXPECT_EQ(TestOnlyRunBasedExtract(arrow::BitUtil::ToLittleEndian(0xFF0AFF),
arrow::BitUtil::ToLittleEndian(0xAFAA)),
arrow::BitUtil::ToLittleEndian(0x00AF));
EXPECT_EQ(TestOnlyRunBasedExtract(arrow::BitUtil::ToLittleEndian(0xFFAAFF),
arrow::BitUtil::ToLittleEndian(0xAFAA)),
arrow::BitUtil::ToLittleEndian(0x03AF));
TEST(TestOnlyExtractBitsSoftware, BasicTest) {
auto check = [](uint64_t bitmap, uint64_t selection, uint64_t expected) -> void {
EXPECT_EQ(TestOnlyExtractBitsSoftware(bitmap, selection), expected);
};
check(0xFF, 0, 0);
check(0xFF, ~uint64_t{0}, 0xFF);
check(0xFF00FF, 0xAAAA, 0x000F);
check(0xFF0AFF, 0xAFAA, 0x00AF);
check(0xFFAAFF, 0xAFAA, 0x03AF);
check(0xFECBDA9876543210ULL, 0xF00FF00FF00FF00FULL, 0xFBD87430ULL);
}

} // namespace internal
Expand Down