Equivalent opposite condition detection
Registered by
Michael Hope
In some conditions the compiler generates a pair of conditional stores with the opposite condition codes. These could be folded into one unconditional store.
Seen in libav in vp8.e
Blueprint information
- Status:
- Complete
- Approver:
- Michael Hope
- Priority:
- Medium
- Drafter:
- Michael Hope
- Direction:
- Approved
- Assignee:
- None
- Definition:
- Approved
- Series goal:
- Accepted for 4.7
- Implementation:
-
Informational
- Milestone target:
-
backlog
- Started by
- Matthew Gretton-Dann
- Completed by
- Matthew Gretton-Dann
Related branches
Related bugs
Sprints
Whiteboard
The code at:
https:/
generates at -O2:
itttt cs
rsbcs r1, r3, r0
rsbcs r5, r5, r2
strcs r5, [r4, #0]
strcs r1, [r4, #16]
itt cc
strcc r5, [r4, #0]
strcc r3, [r4, #16]
So at least the str r5, [r4, #0] can be made unconditional.
[2013-05-22 matthew-
(?)
