[LLVMdev] Let's -disable-post-ra for x86

[Daniel Dunbar]

Hi Jakob,

It's not completely clear from your post, I think your chart is just
for x86_64? What does it look like for x86_32?

 - Daniel

On Thu, Mar 11, 2010 at 4:58 PM, Jakob Stoklund Olesen <stoklund at 2pi.dk> wrote:
> We are currently running the post-ra scheduler for x86 with -O3. It is not really clear that it is worth the compile time.
>
> X86 scheduling is a mystery that post-ra has not solved.
>
> I ran the nightly test suite on x86_64 with LTO enabled and -O3 with and without -disable-post-ra. Code generation is 10% faster overall with -disable-post-ra, and the runtime impact varies from a 17% speedup to a 17 percent slowdown.
>
> Below are the tests that had a more than 3% change in runtime.
>
> I think we should disable post-ra scheduling for x86.
>
>
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