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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Thanks for the fix!<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">However, there still seems to be a problem in that if you pass –ffast-math to clang, then clang changes “sqrt” to be “__sqrt_finite”. LLVM cannot then change
the function call into an x86 sqrt instruction, even with –fno-math-errno set.<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">Can you suggest where I might look in the clang code to find the place where “sqrt” is converted to “__sqrt_finite” and/or the best way to solve this problem?<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">Thanks,<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">Preston<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"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span 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>Chandler Carruth<br>
<b>Sent:</b> Saturday, May 18, 2013 4:48 PM<br>
<b>To:</b> Nadav Rotem<br>
<b>Cc:</b> LLVMdev (LLVMdev@cs.uiuc.edu)<br>
<b>Subject:</b> Re: [LLVMdev] Inlining sqrt library function in X86<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Sat, May 18, 2013 at 5:18 PM, Nadav Rotem <<a href="mailto:nrotem@apple.com" target="_blank">nrotem@apple.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">Does fast-math imply no-math-errno ?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Yes, in both GCC and Clang. Clang does have some annoying logic bugs surrounding this flag though. For example, setting -fno-fast-math would imply no-math-errno, overriding the Linux default. Quite weird. I've cleaned this up some and added
more clear tests in r182203.<o:p></o:p></p>
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