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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I met troubles with jitting x86 codes when using <span style="color:black;background:white;mso-highlight:white">
Intrinsic::x86_sse_ldmxcsr</span><span style="color:black">.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">The target code must execute some SSE2 instruction with DAZ/FTZ modes enabled and others with DAZ/FTZ disabled.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">I’m trying to get this by emitting LDMXCSR instructions with proper flag words.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">It appeared however that execution engine sometimes reorders these instructions with computational ones (say with
<span style="background:white;mso-highlight:white">Intrinsic::x86_sse2_min_pd</span> as we have in the scenario).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">As a result, wrong floating point values are produced.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:black;background:white;mso-highlight:white">The issue disappears when using llvm::CodeGenOpt::None instead of Default</span><span style="color:black">, but of course this is too big hammer for using as a workaround.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:black">Is it a bug, or am I missing some smart settings to prohibit reordering?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:black">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">Mikhail<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
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