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Re: Using cfglayout mode in the selective scheduler
On Mon, Aug 11, 2008 at 10:02 PM, Zdenek Dvorak <rakdver@kam.mff.cuni.cz> wrote:
> Hi,
>
> I am probably missing something:
>
>> The basic idea is enabling cfglayout mode and then ensuring that insn
>> stream and control flow are in sync with each other at all times. This
>> is required because e.g. on Itanium the final bundling happens right
>> after scheduling, and any extra jumps emitted by cfg_layout_finalize
>> will spoil the schedule.
>
> what is the difference between this idea and the cfgrtl mode?
In cfgrtl mode, the functions to manipulate the cfg ensure that the
insn stream and the CFG match. For cfglayout mode you have to do it by
hand. See the earlier discussion about the insn_added hook.
Gr.
Steven