WEBVTT

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Okay, hi everybody, I am Scott.

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My mentor is Nico. I am from

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Perdue University. I am a PhD student.

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My talk is on MIR Optimizations. I work on

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the rust compiler. So this is the "get

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pumped up!" slide. I'm going to tell you

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these things and feel free to cheer

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whenever you're ready. Do you want faster

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programs? Yeah!

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[audience cheering "yeah!"]

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[audience laughs]

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Do you want longer battery life?

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[audience cheering "hell yeah!]

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Do you want more free memory?

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[audience cheering]

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We want all these things and how are we

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going to get them? We're going to get them

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through compiler optimization.

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[audience laughs]

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Okay, so I need to do some background

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before I jump into what I did this summer, but

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it's going to be pretty brief and high

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level, so I'll go fast just so we're all

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on the same page. We start from the Rust

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Source, which Cameron talked about Rust

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in his previous presentation. Basically

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it's a high level systems programming

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language. And the compiler doesn't just

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compile Rust line by line in the machine

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code, it goes through intermediate steps.

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It compiles the Rust Source to High Level

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Intermediate Representation to LLVM

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Intermediate Remediation, and then to

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Machine Code. This is pretty much how most

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compilers work of high level (incoherent)

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languages. You don't want to go from

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Source to Machine Code in one step.

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What we do recently--actually today the

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Rust team flipped the switch and now MIR

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is part of the Rust Compiler. MIR stands

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for "Middle Intermediate Representation"

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and it's coincidentally the same name of a

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space ship...that's the space ship.

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So what did we do? There's now a tiny

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space ship in the compiler and it's

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between the High Level and LLVM IR.

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So, why would we do this? What's MIR

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good for? Basically, it's the simple core

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of Rust. It makes things explicit that

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were not explicit in Rust's code because

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you wouldn't want the [incoherent] to

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detect these things out, obviously. Types

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of variables should be elighted in certain