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Re: [PATCH] i386: Don't use frame pointer without stack access


Hi,

On Mon, 7 Aug 2017, Arjan van de Ven wrote:

> I'm not surprised to see one.
> I'm surprised to see a useless one.
> 
> The "perf" benefit is real, and that's why I asked for one... but the reorder
> made it an expensive 3 instruction nop for all intents and purposes.
> If the pop was just before the ret, sure. It's not.

Okay, that seems a reasonable request.  But IMHO independend from the 
issue of simply ignoring -fno-omit-frame-pointer to which I object.

> Maybe a different angle would be for a peephole phase to just eliminate 
> the useless (even for those who do want a frame pointer) push/mov/pop

For instance.


Ciao,
Michael.


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