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</o:shapelayout></xml><![endif]--></head><body lang=ZH-CN link="#0563C1" vlink="#954F72" style='text-justify-trim:punctuation'><div class=WordSection1><p class=MsoNormal><span lang=EN-US>Hello, I</span>’<span lang=EN-US>m working on the GSoC project </span>“<span lang=EN-US>Integrate Enzyme into Rust to provide high-performance differentiation in Rust</span>”<span lang=EN-US>. I have skimmed over the codebase and now I have some preliminary ideas about the project.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>As you have said, the project can be divided to two main parts:<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt;text-indent:-18.0pt;mso-list:l1 level1 lfo2'><![if !supportLists]><span lang=EN-US><span style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-US>passing and parsing Rust type metadata into LLVM / Enzyme type analysis, and<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt;text-indent:-18.0pt;mso-list:l1 level1 lfo2'><![if !supportLists]><span lang=EN-US><span style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-US>integrating the Enzyme API/pass into rust.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Integrating Enzyme API to rust is trivial by using proc_macros in Rust. However, passing Rust type metadata to LLVM and integrating the Enzyme pass into rust is difficult if we don</span>’<span lang=EN-US>t modify the Rust compiler. The Rust compiler seems to lack ability to emit metadata to LLVM, and if we want to add the Enzyme pass without modifying the compiler, the only way is, I think, using a command like<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><img width=860 height=25 style='width:8.9583in;height:.2604in' id="_x56fe__x7247__x0020_1" src="cid:image003.png@01D725BE.92A91F10"></span><span lang=EN-US><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>which is not user-friendly. I sought hard for a nonintrusive way to implement them but got nothing, so it seems that the only option is modifying the Rust compiler to let it<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo3'><![if !supportLists]><span lang=EN-US><span style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-US>emit extra debuginfo to the generated IR code, and<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo3'><![if !supportLists]><span lang=EN-US><span style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-US>use lld as its linker and add the Enzyme pass to lld<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>with a specific option, say “--enzyme”<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>However, <i>is it appropriate to modify the compiler to just port a plugin to it, though the modification won’t be big or impact the rest of the compiler?</i><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>PS: Another question is about differentiating closures in Rust, but that can be postponed to the following discussions.<o:p></o:p></span></p><div style='mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.0pt;padding:0cm 0cm 1.0pt 0cm'><p class=MsoNormal style='border:none;padding:0cm'><span lang=EN-US><o:p> </o:p></span></p></div><p class=MsoNormal align=right style='text-align:right;word-break:break-all'><span lang=EN-US>Chuyang Chen<o:p></o:p></span></p><p class=MsoNormal align=right style='text-align:right;word-break:break-all'><span lang=EN-US>MSc Student<o:p></o:p></span></p><p class=MsoNormal align=right style='text-align:right;word-break:break-all'><span lang=EN-US>At Department of Computer Science and Technology, Nanjing University<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></body></html>