<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=utf-8">
<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;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman",serif;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p.msonormal0, li.msonormal0, div.msonormal0
{mso-style-name:msonormal;
mso-margin-top-alt:auto;
margin-right:0in;
mso-margin-bottom-alt:auto;
margin-left:0in;
font-size:12.0pt;
font-family:"Times New Roman",serif;}
span.EmailStyle18
{mso-style-type:personal-reply;
font-family:"Calibri",sans-serif;
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri",sans-serif;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
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-US" link="blue" vlink="purple">
<div class="WordSection1">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">If you use the default header file under clang/lib/Headers/opencl-c.h, get_global_id will be mangled.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">If you want to declare get_global_id in your own header, add __attribute__((overloadable)), then it will be mangled.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Sam<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Hongbin Zheng [mailto:etherzhhb@gmail.com]
<br>
<b>Sent:</b> Monday, September 12, 2016 4:21 PM<br>
<b>To:</b> cfe-dev@lists.llvm.org; llvm-dev <llvm-dev@lists.llvm.org>; Liu, Yaxun (Sam) <Yaxun.Liu@amd.com><br>
<b>Subject:</b> builtins name mangling in SPIR 2.0<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<p class="MsoNormal">Hi all,<o:p></o:p></p>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">According to the SPIR 2.0 spec[1], the name of OpenCL builtins are mangled.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">However, when I compile OpenCl code with Clang 3.9 with the "spir64-unknown-unknown" target, Clang generates IR without mangling the builtins, e.g. for:<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<div>
<p class="MsoNormal">__kernel void input_zip_int(__global int *in0) {<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> *in0 = get_global_id(0);<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">}<o:p></o:p></p>
</div>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">clang generates:<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<div>
<p class="MsoNormal">define spir_kernel void @input_zip_int(i32 addrspace(1)* nocapture %in0) local_unnamed_addr #0 !kernel_arg_addr_space !3 !kernel_arg_access_qual !4 !kernel_arg_type !5 !kernel_arg_base_type !5 !kernel_arg_type_qual !6 {<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">entry:<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> %call = tail call spir_func i128 @get_global_id(i32 0) #2<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> %conv = trunc i128 %call to i32<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> store i32 %conv, i32 addrspace(1)* %in0, align 4, !tbaa !7<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> ret void<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">}<o:p></o:p></p>
</div>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">In this case, get_global_id is not mangled to _Z13get_global_idj according to [2].<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Is there an option for clang or an LLVM clang to do the mangling for spir builtins?<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Thanks<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">Hongbin<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">[1] <a href="https://www.khronos.org/registry/spir/specs/spir_spec-2.0.pdf">https://www.khronos.org/registry/spir/specs/spir_spec-2.0.pdf</a>, page 36<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">[2] <a href="https://github.com/KhronosGroup/SPIR-Tools/wiki/SPIR-2.0-built-in-functions">https://github.com/KhronosGroup/SPIR-Tools/wiki/SPIR-2.0-built-in-functions</a><o:p></o:p></p>
</div>
</div>
</div>
</body>
</html>