From: Richard Henderson <richard.henderson@linaro.org>
To: Zack Weinberg <zack@owlfolio.org>, libc-alpha@sourceware.org
Subject: Re: Maybe we should get rid of ifuncs
Date: Tue, 23 Apr 2024 18:41:20 -0700 [thread overview]
Message-ID: <c4600804-6d44-4c94-ad43-60a7dc1ba7a6@linaro.org> (raw)
In-Reply-To: <D0RPG6348D0S.1F9SCYCGKZ3VI@owlfolio.org>
On 4/23/24 11:14, Zack Weinberg wrote:
> (2) Are there existing ifuncs that perform CPU-capability-based
> function selection that*could not* be replaced with an array of bit
> vectors like what I sketched in the previous paragraph?
How much is in actual use, I have no idea. However:
Even x86 cpuid generates a staggeringly large bit vector.
Similarly the arm cpu id register space (some of which is reflected in hwcap; all of which
is available via el0 trap-to-read-filtered-value).
In principal I think the idea of declarative selection is good. It's what I would have
chosen once upon a time if I had been clever enough to invent the correct (almost
certainly target-specific) data structure(s).
r~
next prev parent reply other threads:[~2024-04-24 1:41 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-23 18:14 Maybe we should get rid of ifuncs Zack Weinberg
2024-04-23 18:39 ` enh
2024-04-23 19:46 ` Palmer Dabbelt
2024-04-24 13:56 ` Zack Weinberg
2024-04-24 14:25 ` enh
2024-04-23 18:52 ` Sam James
2024-04-23 18:54 ` Florian Weimer
2024-04-24 13:53 ` Zack Weinberg
2024-04-23 19:26 ` Andreas Schwab
2024-04-24 13:54 ` Zack Weinberg
2024-04-24 1:41 ` Richard Henderson [this message]
2024-04-24 14:43 ` Zack Weinberg
2024-04-24 15:09 ` enh
2024-04-28 0:24 ` Peter Bergner
2024-05-02 2:59 ` Michael Meissner
2024-04-30 8:42 ` Simon Josefsson
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