AArch64: Use b.cond instead of cbz/cbnz when all register are used up #5737
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
`ificmpeq` and its variant nodes have 3 children and the third child is `GlRegDeps` whose children are `aRegLoad`/`iRegLoad`/`PassThrough` of global registers. In some cases, `GlRegDeps` node uses all the allocatable integer registers. If this happens, we cannot use `cbz`/`cbnz` instruction for branch because `cbz`/`cbnz` requires a register in addition to those global registers. This commit changes `ificmpHelper` to use `b.cond` instruction for that case. Signed-off-by: Akira Saitoh <saiaki@jp.ibm.com>
|
This PR should fix eclipse-openj9/openj9#10812 |
|
@genie-omr build aarch64 |
knn-k
approved these changes
Jan 6, 2021
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Outdated suggestions cannot be applied.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.
ificmpeqand its variant nodes have 3 children and the third child isGlRegDepswhose children areaRegLoad/iRegLoad/PassThroughof global registers.In some cases,
GlRegDepsnode uses all the allocatable integer registers.If this happens, we cannot use
cbz/cbnzinstruction for branchbecause
cbz/cbnzrequires a register in addition to those global registers.This commit changes
ificmpHelperto useb.condinstruction for that case.Signed-off-by: Akira Saitoh saiaki@jp.ibm.com