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<p class="MsoNormal">Cameron wrote: <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">> The X86 backend has not been made trap-safe yet. IMO, the lion's share of the trap-unsafe optimizations
<o:p></o:p></p>
<p class="MsoNormal">> are before the backend. <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The x86 backend will be responsible for the paired SSE2 instructions, won’t it? This code uses quite a lot of divides and square roots, and paired instructions without care for the other half of the pair are deadly there.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">> You might get lucky trying the constrained intrinsics now (maybe). <o:p></o:p></p>
<p class="MsoNormal">> That said, performance at this point will be horrible. Perhaps worse than -O0.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Ouch. <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">> I also require something like this for my work. The constrained intrinsics implementation
<o:p></o:p></p>
<p class="MsoNormal">> is a step in the right direction, but there's a long long way to go. You may be able to use
<o:p></o:p></p>
<p class="MsoNormal">> it to flush out Invalid/Overflow/Zero issues in the source, but would not be able to run
<o:p></o:p></p>
<p class="MsoNormal">> production quality code with traps enabled anytime soon.<o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">The source is under continuous development, and we have testing with traps active on MSVC, GCC, Solaris and AIX. They can all manage this with production-quality code. So we’d be looking for problems
created by Clang. Sadly, having floating-point traps active causes actual Clang quality problems to be hidden in the haystack of floating-point errors.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt">-- <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt">John Dallman<o:p></o:p></span></p>
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