<story><title>Mir: A lightweight JIT compiler project</title><url>https://developers.redhat.com/blog/2020/01/20/mir-a-lightweight-jit-compiler-project/</url></story><parent_chain></parent_chain><comment><author>pizlonator</author><text>This project is trying to do too many things.&lt;p&gt;It seems like Ruby needs a profile guided optimizer, which means building an IR that is suitable for profile-guided optimization. That’s way different from classic IRs like this since it means having provisions for OSR exit.&lt;p&gt;I recommend looking at these slides to learn how to do it.&lt;p&gt;&lt;a href=&quot;http:&amp;#x2F;&amp;#x2F;www.filpizlo.com&amp;#x2F;slides&amp;#x2F;pizlo-speculation-in-jsc-slides.pdf&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;www.filpizlo.com&amp;#x2F;slides&amp;#x2F;pizlo-speculation-in-jsc-slid...&lt;/a&gt;
&lt;a href=&quot;http:&amp;#x2F;&amp;#x2F;www.filpizlo.com&amp;#x2F;slides&amp;#x2F;pizlo-splash2018-jsc-compiler-slides.pdf&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;www.filpizlo.com&amp;#x2F;slides&amp;#x2F;pizlo-splash2018-jsc-compiler...&lt;/a&gt;</text></comment>
<story><title>Mir: A lightweight JIT compiler project</title><url>https://developers.redhat.com/blog/2020/01/20/mir-a-lightweight-jit-compiler-project/</url></story><parent_chain></parent_chain><comment><author>bakery2k</author><text>From GitHub [1]:&lt;p&gt;&lt;pre&gt;&lt;code&gt;  &amp;quot;Plans to try MIR light-weight JIT first for CRuby or&amp;#x2F;and MRuby implementation&amp;quot;
  &amp;quot;MIR is strongly typed&amp;quot;
&lt;/code&gt;&lt;/pre&gt;
Is there an explanation of how the project bridges the gap between dynamically-typed Ruby and statically-typed MIR?&lt;p&gt;More generally, I&amp;#x27;d love to see something like MRuby+MIR be successful. It would be great to see an alternative to the aging LuaJIT.&lt;p&gt;[1] &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;github.com&amp;#x2F;vnmakarov&amp;#x2F;mir&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;github.com&amp;#x2F;vnmakarov&amp;#x2F;mir&lt;/a&gt;</text></comment>