Skip to content

GH-51127: [C++] Fix is_null nan_is_null for dictionary-encoded float arrays #51000

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
pitrou merged 4 commits into from
Sep 28, 2026
Merged

GH-51127: [C++] Fix is_null nan_is_null for dictionary-encoded float arrays #51000

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
59ca9af
GH-51127: [C++] Fix is_null nan_is_null for dictionary-encoded float …
shoemoney Sep 25, 2026
61bef91
GH-51127: [C++] Check dictionary indices before validity lookup
shoemoney Sep 25, 2026
ca96314
GH-51127: [C++] Simplify dictionary NaN null checks
shoemoney Sep 28, 2026
a78401d
GH-51127: Combine dictionary null bits in one bitmap pass
shoemoney Sep 28, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
53 changes: 47 additions & 6 deletions cpp/src/arrow/compute/kernels/scalar_validity.cc
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -21,8 +21,11 @@
#include "arrow/compute/kernels/common_internal.h"
#include "arrow/compute/registry_internal.h"

#include "arrow/compute/api_vector.h"
#include "arrow/type.h"
#include "arrow/util/bit_util.h"
#include "arrow/util/bitmap_ops.h"
#include "arrow/util/checked_cast.h"
#include "arrow/util/dict_util_internal.h"
#include "arrow/util/float16.h"
#include "arrow/util/logging_internal.h"
Expand Down Expand Up @@ -80,10 +83,42 @@ static void SetNanBits(const ArraySpan& arr, uint8_t* out_bitmap, int64_t out_of
}
}

// Maps `is_null` over dictionary values and then through the indices, so
// both NaN and null dictionary entries are reported, whatever the index type.
static Status SetNanBitsFromDictionary(KernelContext* ctx, const ArraySpan& arr,
uint8_t* out_bitmap, int64_t out_offset) {
if (arr.length == 0) {
return Status::OK();
}
NullOptions nan_is_null_options(/*nan_is_null=*/true);
ARROW_ASSIGN_OR_RAISE(Datum dict_is_null,
CallFunction("is_null", {arr.dictionary().ToArrayData()},
&nan_is_null_options, ctx->exec_context()));

const auto& dict_type = checked_cast<const DictionaryType&>(*arr.type);
auto indices = ArrayData::Make(dict_type.index_type(), arr.length,
{arr.GetBuffer(0), arr.GetBuffer(1)}, arr.GetNullCount(),
arr.offset);
ARROW_ASSIGN_OR_RAISE(Datum taken,
Take(dict_is_null, Datum(std::move(indices)),
TakeOptions::NoBoundsCheck(), ctx->exec_context()));

const ArrayData& result = *taken.array();
if (arr.GetNullCount() > 0) {
::arrow::internal::BitmapOrNot(result.buffers[1]->data(), result.offset,
arr.buffers[0].data, arr.offset, arr.length,
out_offset, out_bitmap);
} else {
CopyBitmap(result.buffers[1]->data(), result.offset, arr.length, out_bitmap,
out_offset);
}
return Status::OK();
}

// `nan_is_null` can only be true for the is_null kernel since the is_valid and
// true_unless_null kernels currently do not take `NullOptions`
Status SetLogicalNullBits(const ArraySpan& span, uint8_t* out_bitmap, int64_t out_offset,
bool set_on_null, bool nan_is_null) {
Status SetLogicalNullBits(KernelContext* ctx, const ArraySpan& span, uint8_t* out_bitmap,
int64_t out_offset, bool set_on_null, bool nan_is_null) {
const Type::type t = span.type->id();
if (t == Type::NA) {
// Input is all nulls, so all output bits are the same.
Expand All @@ -98,7 +133,10 @@ Status SetLogicalNullBits(const ArraySpan& span, uint8_t* out_bitmap, int64_t ou
// TODO: propagate `nan_is_null`
ree_util::SetLogicalNullBits(span, out_bitmap, out_offset, set_on_null);
} else if (t == Type::DICTIONARY) {
// TODO: propagate `nan_is_null`
const auto& dict_type = checked_cast<const DictionaryType&>(*span.type);
if (nan_is_null && is_floating(dict_type.value_type()->id())) {
return SetNanBitsFromDictionary(ctx, span, out_bitmap, out_offset);
}
dict_util::SetLogicalNullBits(span, out_bitmap, out_offset, set_on_null);
} else {
// Input is a type for which logical and physical nulls are the same, so we can
Expand Down Expand Up @@ -141,13 +179,15 @@ Status SetLogicalNullBits(const ArraySpan& span, uint8_t* out_bitmap, int64_t ou

Status IsValidExec(KernelContext* ctx, const ExecSpan& batch, ExecResult* out) {
ArraySpan* out_span = out->array_span_mutable();
return SetLogicalNullBits(batch[0].array, out_span->buffers[1].data, out_span->offset,
return SetLogicalNullBits(ctx, batch[0].array, out_span->buffers[1].data,
out_span->offset,
/*set_on_null=*/false, /*nan_is_null=*/false);
}

Status IsNullExec(KernelContext* ctx, const ExecSpan& batch, ExecResult* out) {
ArraySpan* out_span = out->array_span_mutable();
return SetLogicalNullBits(batch[0].array, out_span->buffers[1].data, out_span->offset,
return SetLogicalNullBits(ctx, batch[0].array, out_span->buffers[1].data,
out_span->offset,
/*set_on_null=*/true,
/*nan_is_null=*/NanOptionsState::Get(ctx).nan_is_null);
}
Expand Down Expand Up @@ -265,7 +305,8 @@ Status TrueUnlessNullExec(KernelContext* ctx, const ExecSpan& batch, ExecResult*
// NullHandling::INTERSECTION and change the validity checks in exec.cc so that
// they correctly handle logical nulls, but that would invove significant changes
// in exec.cc which might have more side effects
return SetLogicalNullBits(batch[0].array, out_span->buffers[0].data, out_span->offset,
return SetLogicalNullBits(ctx, batch[0].array, out_span->buffers[0].data,
out_span->offset,
/*set_on_null=*/false, /*nan_is_null=*/false);
}

Expand Down
33 changes: 33 additions & 0 deletions cpp/src/arrow/compute/kernels/scalar_validity_test.cc
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -208,6 +208,39 @@ TEST(TestValidityKernels, IsNullSetsZeroNullCount) {
ASSERT_EQ(out.array()->null_count, 0);
}

TEST(TestValidityKernels, IsNullDictionaryNanIsNull) {
NullOptions default_options;
NullOptions nan_is_null_options(/*nan_is_null=*/true);

for (const auto& value_type : {float16(), float32(), float64()}) {
SCOPED_TRACE(value_type->ToString());
auto dict_ty = dictionary(int32(), value_type);
auto arr =
DictArrayFromJSON(dict_ty, "[0, 1, 2, 3, null, 1]", "[1.5, NaN, -0.0, null]");

// Null dictionary values and null indices are always null.
CheckScalarUnary(
"is_null", arr,
ArrayFromJSON(boolean(), "[false, false, false, true, true, false]"));
CheckScalarUnary("is_null", arr,
ArrayFromJSON(boolean(), "[false, false, false, true, true, false]"),
&default_options);
CheckScalarUnary("is_null", arr,
ArrayFromJSON(boolean(), "[false, true, false, true, true, true]"),
&nan_is_null_options);

auto no_null_indices =
DictArrayFromJSON(dict_ty, "[3, 1, 0, 2]", "[1.5, NaN, -0.0, null]");
CheckScalarUnary("is_null", no_null_indices,
ArrayFromJSON(boolean(), "[true, true, false, false]"),
&nan_is_null_options);

auto empty = DictArrayFromJSON(dict_ty, "[]", "[]");
CheckScalarUnary("is_null", empty, ArrayFromJSON(boolean(), "[]"),
&nan_is_null_options);
}
}

template <typename ArrowType>
class TestFloatingPointValidityKernels : public TestValidityKernels<ArrowType> {
public:
Expand Down
Loading