[llvm-dev] Is the correct behavior of getelementptr i192* for opt + llc -march=aarch64?

MITSUNARI Shigeo via llvm-dev llvm-dev at lists.llvm.org
Fri Nov 11 19:42:01 PST 2016


Hi Renato,

> I believe Tom's point was about the line:
>
> % opt-3.8 -O3 a.ll -o - | llc-3.8 -O3 -o - -march=aarch64
>
> If your host is x86_64, then the first call to opt will assume x86_64
> unless you have a triple in the IR (which I believe you didn't).

Thank you, I lost it, but I always use opt and llc on each host and do not mix them.
I'm sorry, I should have written %opt -O3 a.ll -o -|llc -O3 -o - (on x86-64 / aarch64).

> % opt-3.8 -O3 a.ll -o - | llc-3.8 -O3 -o - -march=aarch64

> Also, don't assume that OPT+LLC == LLC, as you'll be running more of
> the same passes on the first case, which can, in rare cases, have an
> impact (for better or worse) on the code generated.
>
> I recommend you keep the passes to a minimum. Opt is a debug tool, not
> an optimiser.

I see, but I want load192() in the previous mail should be inlined, but
only llc does not it if alwaysinline attribute is add.

Yours,
 Shigeo


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