[Bug target/43440] Overwriting neon quad register does not clobber all included single registers

["siarhei dot siamashka at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #6 from siarhei dot siamashka at gmail dot com  2010-03-21 03:56 -------
(In reply to comment #4)
> IMO the reasons as described in my email  is another motivation for Neon
> programmers to be using intrinsics rather than inline assembler and to improve
> in general Neon intrinsics.

The problem is that today neon intrinsics have a lot more issues in practice.
The resulting code is way too slow to be usable, especially when gcc thinks
that it is running out of registers and starts spilling variables to memory.
Bug 43118 and bug 43364 are just some very basic examples of performance issues
without looking any deeper. Not having many bugs in bugzilla for NEON
intrinsics means that either they work good enough or nobody seriously uses
them. At least for me it is the latter case.

Autovectorization is even worse than intrinsics.

Inline assembly has a few bugs, but they can be easily workarounded.

Sorry for this rant/offtopic. Just thought that you might be somewhat
interested the opinion of someone from the other side of the fence :-)


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siarhei dot siamashka at gmail dot com changed:

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                 CC|                            |siarhei dot siamashka at
                   |                            |gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43440