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Re: [RFC] try to generate FP and/or/xor instructions for SSE

From: Paolo Bonzini <bonzini at gnu dot org>
To: tbp <tbptbp at gmail dot com>
Cc: Ross Ridge <rridge at csclub dot uwaterloo dot ca>, GCC Patches <gcc-patches at gcc dot gnu dot org>
Date: Thu, 23 Aug 2007 16:33:19 +0200
Subject: Re: [RFC] try to generate FP and/or/xor instructions for SSE
References: <20070823013503.426FE74B95@caffeine.csclub.uwaterloo.ca> <46CD273E.6060009@gnu.org> <46CD705E.90701@gmail.com> <46CD72E0.3000005@lu.unisi.ch> <46CD7ACA.8050904@gmail.com> <46CD8E69.4060402@gnu.org> <4fc48eb10708230709v1c82d957y5b3101445d56fc00@mail.gmail.com>

I'll hijack that discussion and ask if there's some reason to
misrepresent those builtins
     v4si __builtin_ia32_cmpeqps (v4sf, v4sf)
     v4si __builtin_ia32_cmpltps (v4sf, v4sf)
     v4si __builtin_ia32_cmpleps (v4sf, v4sf)
     v4si __builtin_ia32_cmpgtps (v4sf, v4sf)
     v4si __builtin_ia32_cmpgeps (v4sf, v4sf)
     ...etc...
as returning a v4si?

Well, they return a mask and an all-ones floating point value does not make much sense. Do you get pessimizations out of that? With a patch like this one, though, you should not, so I could try it on a small test case if you sent it.

Paolo

Follow-Ups:
- Re: [RFC] try to generate FP and/or/xor instructions for SSE
  - From: tbp

References:
- [RFC] try to generate FP and/or/xor instructions for SSE
  - From: Paolo Bonzini
- Re: [RFC] try to generate FP and/or/xor instructions for SSE
  - From: tbp

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