Allow pointers to evaluate to true/false #3656
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
amscanne
force-pushed
the
truthy
branch
2 times, most recently
from
9b27524 to
e7e630a
Compare
amscanne
requested review from
ajor,
viktormalik,
danobi,
fbs and
jordalgo
as code owners
jordalgo
requested changes
Dec 27, 2024
danobi
reviewed
Dec 27, 2024
amscanne
force-pushed
the
truthy
branch
4 times, most recently
from
6361560 to
27f3b70
Compare
jordalgo
reviewed
Dec 28, 2024
danobi
approved these changes
Dec 29, 2024
For if conditions, tenary conditions and logical expressions we can allow pointers to evaluate to true or false. This change updates the codegen to consistently use the null value for the `lhs` and `rhs`, and allows the appropriate conditions in the semantic analyzer. Runtime tests are added to ensure that the given programs evaluate to the expected outcomes. This fixes bpftrace#1579, but should only update bpftrace#1726. The question of broader expanding logical operators to strings and other types is trickier, but the null value for pointers is fairly well-understood and a very common pattern for C programmers (who will often write these probes). The updates to documentation are minimal, as existing constraints are not documented and it seems that using pointers generally matches user expectations.
jordalgo
approved these changes
Dec 30, 2024
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
For if conditions, tenary expressions and logical expressions we can allow pointers to evaluate to true or false. This change updates the codegen to consistently use the null value for the
lhsandrhs, and allows the appropriate conditions in the semantic analyzer. Runtime tests are added to ensure that the given programs evaluate to the expected outcomes.This fixes #1579, but should only update #1726. The question of broader expanding logical operators to strings and other types is trickier, but the null value for pointers is fairly well-understood and a very common pattern for C programmers (who will often write these probes).
Checklist
man/adoc/bpftrace.adocCHANGELOG.md