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Re: [RFC] Contributing tree-ssa to mainline
- From: kenner at vlsi1 dot ultra dot nyu dot edu (Richard Kenner)
- To: rth at redhat dot com
- Cc: gcc at gcc dot gnu dot org
- Date: Mon, 19 Jan 04 06:47:02 EST
- Subject: Re: [RFC] Contributing tree-ssa to mainline
So we've missed the required factor of 2 on this test case by 0.8%.
Since that seems likely to be in the relm of measurement error, I
think that should qualify.
I agree.
With a bit more work unwravelling C++ front-end obfuscation, I would
expect the 10-20% to be visible on just about any object abstraction
test case. Particularly for any object that has more than one field,
and thus can't benefit from rtl addressof. That seems like it should
be a large enough class to qualify.
Likewise.
However, it would be good to see cases of both of the above for C as well as
C++: if the gain is just C++, one could argue that the most appropriate place
for such code is in the C++ front end. (There are Ada-specific optimizations
in the Ada front end, for example.)
The tree-ssa infrastructure is supposed to benefit *all* languages. If
benefits can be shown in C, they will clearly apply to all languages. But
that's not true for C++.