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Re: PPC64 libmvec sincos/sincosf ABI
- From: Joseph Myers <joseph at codesourcery dot com>
- To: Wilco Dijkstra <Wilco dot Dijkstra at arm dot com>
- Cc: 'GNU C Library' <libc-alpha at sourceware dot org>, "tnggil at protonmail dot com" <tnggil at protonmail dot com>, nd <nd at arm dot com>
- Date: Tue, 6 Aug 2019 20:31:00 +0000
- Subject: Re: PPC64 libmvec sincos/sincosf ABI
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On Tue, 6 Aug 2019, Wilco Dijkstra wrote:
> I don't think it is related to the target - the fastest ABI is one that avoids
> unnecessary work. For example scalar sincos is slow due to the inefficient
> ABI which forces the results through memory (fixing that gives a 50% speedup).
At the scalar API level this is an argument for the previously discussed
idea of adding cexpi functions to <complex.h> (as a GNU extension and
potentially something proposed for standardization).
You'd then have the question of what the API and ABI should look like for
declaring to the compiler that cexpi has certain corresponding vector
functions available.
--
Joseph S. Myers
joseph@codesourcery.com