Hi Jie, On 18.10.2010 10:49, Jie Zhang wrote:
When this error happens, FENCE_ISSUED_INSNS (fence) is 2 and issue_rate is 1. PowerPC 8540 is capable to issue 2 instructions in one cycle, but rs6000_issue_rate lies to scheduler that it can only issue 1 instruction before register relocation is done. See the following code:
See PR 45352. I've tried to fix this in the selective scheduler by modeling the lying behavior in line with the haifa scheduler. Let me know if the last patch from the PR audit trail doesn't work for you.
In addition, after the above patch goes in, I can make the selective scheduler not try to jump through the hoops with putting correct sched cycles on insns for targets which don't need it in their target_finish hook. I guess powerpc needs this though, but x86-64 (for which PR 45342 was opened) almost surely does not.
Thanks, Andrey
