lriggs opened a new pull request, #48597:
URL: https://github.com/apache/arrow/pull/48597
This PR supersedes 38790 since that has been inactive for a few years.
Rationale for this change
In Gandiva, it has been observed that the tool caches compiled expressions.
However, when using the expression cache, Gandiva takes into account the
schema, expr->ToString, and specific parameters. Nevertheless, in
llvm_generator.cc, Gandiva still traverses the expressions to generate LLVM IR
code and then produces specific JIT functions. Considering that llvm_generator
traverses expressions and calculates the memory start positions of fields
involved in the computation, we can further enhance Gandiva's caching mechanism.
Specifically, we can exclude the influence of the schema. Simultaneously, we
can also exclude the field names' information involved in the expression
computation. For example, for a schema {f0:int32, f1:int32} with an expression
add(f0, f1), we can cache it initially. Then, for a schema {a0:int32, a1:int32,
a2:int32} with an expression add(a1, a2), it should not require recompilation;
it can directly reuse the JIT function generated by the expression {f0:int32,
f1:int32}, add(f0, f1).
What changes are included in this PR?
This PR primarily alters the construction of the cache key and makes
modifications to the schema validation in both the projector and filter. It
also adjusts the validation of fields in expr_validator. Additionally, a
ToCacheKeyString function has been added to each node. This PR mainly focuses
on these areas.
Are these changes tested?
Yes,these changes are tested.
Are there any user-facing changes?
No.
https://github.com/apache/arrow/issues/38792
Closes: https://github.com/apache/arrow/issues/38792
--
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: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
