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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Sorry: the occurrence of fast-math is a typo for another unsafe-fp-math. Although unsafe-fp-math is more conservative I still think it's too aggressive for controlling this.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> llvmdev-bounces@cs.uiuc.edu [mailto:llvmdev-bounces@cs.uiuc.edu] <b>On Behalf Of </b>David Tweed<br><b>Sent:</b> 20 March 2013 09:58<br><b>To:</b> Renato Golin; LLVM Dev<br><b>Subject:</b> Re: [LLVMdev] ARM NEON VMUL.f32 issue<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><span style='color:#1F497D'>Hi,<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>| </span>The question is:<o:p></o:p></p></div><div><p class=MsoNormal><span style='color:#1F497D'>|</span> * is this a problem with the test, that shouldn't be expecting values below FLT_MIN, or<o:p></o:p></p></div><div><p class=MsoNormal><span style='color:#1F497D'>|</span> * is it a bug in the lowering, that should only be lowering to NEON's VMUL when unsafe-math is on, or<o:p></o:p></p></div><div><p class=MsoNormal><span style='color:#1F497D'>|</span> * neither, and people should disable that when they want correctness?<span style='color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Note that if you go for the second option, IMO unsafe-math is _far_ too "aggressive" an option to control this whether multiplies should be allowed produce denormals. I can imagine plenty of cases where I wouldn't care about denormals, but wouldn't want some of the other fast-math semantics applied. Does llvm/clang have any option like strict-iee754 that users can toggle to control things like this?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Cheers,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Dave<o:p></o:p></span></p></div></div><p class=MsoNormal><br><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>-- IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.</span><o:p></o:p></p></div></body></html>