Check whether array index variable is an induction variable #15870
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
In examining an array index for Idiom Recognition, analyzeOneArrayIndex checks whether the variable operand in a 'var + const' or 'const + var' expression is an induction variable. On the other hand, if the expression is a simple variable, the analysis assumes the variable reference is acceptable. However, it can happen that the variable used as the array index is not an induction variable which can result in an incorrect transformation. Fixed this by adding a check that an arrayindex that is a variable is also an induction variable. Fixes eclipse-openj9#15474 Signed-off-by: Henry Zongaro <zongaro@ca.ibm.com>
|
@jdmpapin Devin, may I ask you to review this change? |
jdmpapin
approved these changes
Sep 14, 2022
|
Jenkins test sanity all jdk17 |
This was referenced Sep 15, 2022
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Outdated suggestions cannot be applied.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.
In examining an array index for Idiom Recognition,
analyzeOneArrayIndexchecks whether the variable operand in a 'var + const' or 'const + var' expression is an induction variable. On the other hand, if the expression is a simple variable, the analysis assumes the variable reference is acceptable. However, it can happen that the variable used as the array index is not an induction variable which can result in an incorrect transformation.Fixed this by adding a check that an array index that is a variable is also an induction variable.
Fixes #15474
Signed-off-by: Henry Zongaro zongaro@ca.ibm.com