<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=us-ascii"><meta name=Generator content="Microsoft Word 15 (filtered medium)"><style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:"Book Antiqua";
panose-1:2 4 6 2 5 3 5 3 3 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif;
mso-fareast-language:EN-US;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:#0563C1;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Book Antiqua",serif;
color:windowtext;
font-weight:normal;
font-style:normal;
text-decoration:none none;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri",sans-serif;
mso-fareast-language:EN-US;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:72.0pt 72.0pt 72.0pt 72.0pt;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]--></head><body lang=EN-IE link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'>Hi LLVM-Dev,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'>I am trying to implement support for emulated FP64 on our target. Many operations work fine, invoking the appropriate helper function in ‘</span><span lang=EN-GB style='font-size:12.0pt;font-family:"Courier New"'>compiler-rt</span><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'>’. But we don’t have a specific register class for FP64 and LLVM usually selects a pair of 32-bit integers, which is fine. The problem is that it doesn’t “always” select a pair of 32-bit integers, and then I get an assertion in ‘</span><span lang=EN-GB style='font-size:12.0pt;font-family:"Courier New"'>TargetRegisterInfo::getMinimalPhysRegClass</span><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'>’ that says “Couldn’t find the register class”.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'>The funny thing is that something like ‘</span><span lang=EN-GB style='font-size:12.0pt;font-family:"Courier New"'>a = b * c;</span><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'>’ works perfectly, but the much simple ‘</span><span lang=EN-GB style='font-size:12.0pt;font-family:"Courier New"'>a = b;</span><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'>’ causes this assertion.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'>We have not used ‘</span><span lang=EN-GB style='font-size:12.0pt;font-family:"Courier New"'>setOperationAction</span><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'>’ for any of the FP64 operations, nor have we created a special register class for them either, in the expectation that it would just reduce to the underlying integers and ‘</span><span lang=EN-GB style='font-size:12.0pt;font-family:"Courier New"'>compiler-rt</span><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'>’ calls.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'>I’m a bit stumped, so does anyone have any advice about how I should describe our target so that it supports emulated FP64 using either a pair of 32-bit integers or a single 64-bit register as the underlying implementation type?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'>Thanks,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'> MartinO - Movidius<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua",serif'><o:p> </o:p></span></p></div></body></html>