felipecrv commented on code in PR #41975:
URL: https://github.com/apache/arrow/pull/41975#discussion_r1645229813
##########
cpp/src/arrow/compute/exec.cc:
##########
@@ -1034,9 +1034,23 @@ class VectorExecutor : public
KernelExecutorImpl<VectorKernel> {
output_num_buffers_ =
static_cast<int>(output_type_.type->layout().buffers.size());
// Decide if we need to preallocate memory for this kernel
- validity_preallocated_ =
- (kernel_->null_handling != NullHandling::COMPUTED_NO_PREALLOCATE &&
- kernel_->null_handling != NullHandling::OUTPUT_NOT_NULL);
+ validity_preallocated_ = false;
+ if (output_type_.type->id() != Type::NA) {
+ if (kernel_->null_handling == NullHandling::COMPUTED_PREALLOCATE) {
+ // Override the flag if kernel asks for pre-allocation
+ validity_preallocated_ = true;
+ } else if (kernel_->null_handling == NullHandling::INTERSECTION) {
+ bool elide_validity_bitmap = true;
+ for (const auto& arg : batch.values) {
+ auto null_gen = NullGeneralization::Get(arg) ==
NullGeneralization::ALL_VALID;
+
+ // If not all valid, this becomes false
+ elide_validity_bitmap = elide_validity_bitmap && null_gen;
+ }
+ validity_preallocated_ = !elide_validity_bitmap;
+ }
+ }
Review Comment:
I think the handling of list-view types in the pre-allocation code is good.
The 3rd commit has a mix of things in it.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: github-unsubscr...@arrow.apache.org
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org
