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Re: RFC: LRA for x86/x86-64 [0/9]
On Sun, Sep 30, 2012 at 6:52 PM, Steven Bosscher <stevenb.gcc@gmail.com> wrote:
> Hi,
>
>
> To look at it in yet another way:
>
>> integrated RA : 189.34 (16%) usr
>> LRA non-specific : 59.82 ( 5%) usr
>> LRA virtuals eliminatenon: 56.79 ( 5%) usr
>> LRA create live ranges : 175.30 (15%) usr
>> LRA hard reg assignment : 130.85 (11%) usr
>
> The IRA pass is slower than the next-slowest pass (tree PRA) by almost
> a factor 2.5. Each of the individually-measured *phases* of LRA is
> slower than the complete IRA *pass*. These 5 timevars together make up
> for 52% of all compile time.
That figure indeed makes IRA + LRA look bad. Did you by chance identify
anything obvious that can be done to improve the situation?
Thanks,
Richard.
> IRA already has scalability problems, let's not add more of that with LRA.
>
> Ciao!
> Steven