Scheduling and inserting NOPs

[Boris Boesler]

Am 21.11.2007 um 18:39 schrieb Andrew Haley:

>> Walk the instructions in each BB, and if you see a violation stuff  
>> a NOP.
>>
>> This is so simple that I'm wondering if there's something important
>> that I'm failing to understand.
>
> Ah, hold on.  Is it that you don't know where sched inserted the empty
> cycles, and there's no easy way to find out?

  Finally. YES.

  To solve this someone simply stored cycle and insn (recorded in  
TARGET_SCHED_REORDER) in a hash-table and reused this info in  
TARGET_MACHINE_DEPENDENT_REORG. But I read that there passes which  
might reorder or insert additional code. In that case the info in the  
hash-table might be incorrect or not valid.

  Any ideas?

Boris