Balaji V. Iyer wrote:
I am porting GCC 4.0.0 to a proprietary VLIW machine, and I want to
insert NOPs explicitly wherever there is an Output/Flow/Anti dependencies. I
am currently doing this insertion in the machine dependent reorganization
phase. Is there a way to do this in machine description file (or during
scheduling phase) itself (or a better way to do this)?
You could look at what the IA-64 port does. We delay the second
scheduling pass until the mach dep reorg pass, and then use scheduler
hooks to insert the padding nops we need. We also do bundling at the
same time. This gets pretty complicated for IA-64 because of the
bundling issues, but it is doable.
Otherwise, no, there is no simple way to do this other than what you are
already doing.
--
Jim Wilson, GNU Tools Support, http://www.specifix.com
