[Bug rtl-optimization/63384] selective scheduling on x86 takes very long

[andi-gcc at firstfloor dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63384

--- Comment #3 from Andi Kleen <andi-gcc at firstfloor dot org> ---
It loops (forever?) on this in sched2:


Scheduling on fences: (uid:28;seqno:7;) 
Fence 28[2] has not changed

Scheduling on fences: (uid:28;seqno:7;) 
Fence 28[2] has not changed

Scheduling on fences: (uid:28;seqno:7;) 
Fence 28[2] has not changed

Scheduling on fences: (uid:28;seqno:7;) 
Fence 28[2] has not changed

Scheduling on fences: (uid:28;seqno:7;) 
Fence 28[2] has not changed

Scheduling on fences: (uid:28;seqno:7;) 
Fence 28[2] has not changed

Scheduling on fences: (uid:28;seqno:7;) 
Fence 28[2] has not changed

Scheduling on fences: (uid:28;seqno:7;) 
Fence 28[2] has not changed