The following kind of instruction sequences break the return stack predictor: MOV LR, PC MOV PC, Rx We should avoid it above v4. The BLX instruction should be used for predicted calls on ARMv5 and above. The patch gives 2% performance progression.
Created attachment 53824 [details] Use BLX and BX to keep happy the return stack predictor above ARMv4
Created attachment 53826 [details] The results on ARMv7
Comment on attachment 53824 [details] Use BLX and BX to keep happy the return stack predictor above ARMv4 Clearing flags on attachment: 53824 Committed r58091: <http://trac.webkit.org/changeset/58091>
All reviewed patches have been landed. Closing bug.