<html 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:0cm;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
.MsoChpDefault
{mso-style-type:export-only;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:70.85pt 2.0cm 70.85pt 2.0cm;}
div.WordSection1
{page:WordSection1;}
--></style>
</head>
<body lang="EN-GB">
<div class="WordSection1">
<p class="MsoNormal"><span lang="FI">Dear LLVMers,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="FI"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="FI">I’m investigating the response time of my JIT, and according to profiling, optimization takes 85% of the compile time, while the rest is being split evenly between the front-end and machine code generation. Much of the optimizer
time is spent in various alias analysis passes. <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="FI"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="FI">I’m happy with the generated code quality and wouldn’t like to lower the optimization level (O2).<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="FI"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="FI">Would generating alias metadata from the front-end help and speed up optimization?
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="FI"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="FI">If so, what kind of AA would have the best return on investment in terms of compile time? TBAA is not applicable to my language, but I could provide C99 restrict and related semantics fairly easily.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="FI"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="FI">Thanks!!<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Vesa Norilo<br>
Lecturer<br>
Centre for Music and Technology<br>
University of Arts Helsinki</p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif"><o:p> </o:p></span></p>
</div>
</body>
</html>