Re: [PATCH v2 1/4] x86: Use the default ABI for the 32-bit vDSO

[Andy Lutomirski]

On Fri, Feb 28, 2014 at 7:06 AM, H. Peter Anvin <hpa@xxxxxxxxx> wrote:
> How many internal function calls are there? It seems we should try to avoid those as much as possible by suitable inlining.

There are no non-static calls at all, except for __x86.get_pc_thunk.
I imagine that gcc is smart enough to improve the calling convention
to non-externally-visible functions.

Amazingly (to me, anyway), the performance of the 32-bit version seems
to be within 1 ns or so of the 64-bit version on SNB.  I suspect that
Intel has optimized the crap out of these things.

--Andy
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