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Advanced Compilers: Self-Guided Online Course

cs.cornell.edu

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Re: Advanced Compilers: Self-Guided Online Course

#71

Post by woodruffw »

ibains wrote: post #59

I’ve worked on multiple compilers (optimizations expert) at MSFT on VS and CUDA and gave developed a DSL and worked on Database Compilers. I can’t hire compiler people with right skills. We’re building an IDE and those parsers are written differently, and we use Scala packrat parser combinators. These courses teach very little judgement or industry relevant stuff. When do you use packrat parser vs LALR vs LL? Good lu…

I second this (although I work more on translation and modeling than optimization). IME, it's much easier to find otherwise competent, savvy researchers and spin them onto compiler work than it is to take someone who's gone through an "advanced" course.

Re: Advanced Compilers: Self-Guided Online Course

#72

Post by [deleted] »

ibains wrote: post #59

I’ve worked on multiple compilers (optimizations expert) at MSFT on VS and CUDA and gave developed a DSL and worked on Database Compilers. I can’t hire compiler people with right skills. We’re building an IDE and those parsers are written differently, and we use Scala packrat parser combinators. These courses teach very little judgement or industry relevant stuff. When do you use packrat parser vs LALR vs LL? Good lu…

[deleted]

Re: Advanced Compilers: Self-Guided Online Course

#73

Post by abdullahkhalids »

mcguire wrote: post #17

The course materials look good. But what is a "PhD level course"? All I've seen is undergrad and graduate, and the difference between masters and PhD has nothing to do with classes.

There is no formal difference between masters and PhD courses. I think he calls it a PhD level course because it is "research oriented" and requires work that perhaps a Masters student looking to complete credits might not be interested in.

The evaluation criteria is also fairly subjective and rough, which might not work for a larger masters level course.

Re: Advanced Compilers: Self-Guided Online Course

#74

Post by nialv7 »

ibains wrote: post #59

I’ve worked on multiple compilers (optimizations expert) at MSFT on VS and CUDA and gave developed a DSL and worked on Database Compilers. I can’t hire compiler people with right skills. We’re building an IDE and those parsers are written differently, and we use Scala packrat parser combinators. These courses teach very little judgement or industry relevant stuff. When do you use packrat parser vs LALR vs LL? Good lu…

No offence, but parsing (in a compiler, not in general) is probably the most boring part of a compiler.

As this is a PhD course, I'd expect the goal of it to be preparing students for research in the field, not writing parsers for some industrial company.

Also, there are definitely courses that teach you how to write a parser. But we usually don't call them advanced.

Re: Advanced Compilers: Self-Guided Online Course

#75

Post by nicoburns »

cinericius wrote: post #69
ibains wrote: post #59

I’ve worked on multiple compilers (optimizations expert) at MSFT on VS and CUDA and gave developed a DSL and worked on Database Compilers. I can’t hire compiler people with right skills. We’re building an IDE and those parsers are written differently, and we use Scala packrat parser combinators. These courses teach very little judgement or industry relevant stuff. When do you use packrat parser vs LALR vs LL? Good lu…

Do you think it is the responsibility of academia to teach "industry relevant stuff"? I agree that courses generally don't teach judgement well, but I do think that it is the workplace/industry's responsbility to train their engineers and not expect fresh grads to be fully equipped to work on something that specific.

I definitely think there ought to be courses on such things available. There should be an educational route that is between pure academia which focusses on esoterica that is only relevant to research and vocational courses that don't include much innthe way of theory at all. The idea that industry ought to pay for it presumably comes from a background where universities are private an expensive. But I'd like to live in a world where these kind of courses were government subsidised and available for free or cheap.

Re: Advanced Compilers: Self-Guided Online Course

#76

Post by bachmeier »

ibains wrote: post #59

I’ve worked on multiple compilers (optimizations expert) at MSFT on VS and CUDA and gave developed a DSL and worked on Database Compilers. I can’t hire compiler people with right skills. We’re building an IDE and those parsers are written differently, and we use Scala packrat parser combinators. These courses teach very little judgement or industry relevant stuff. When do you use packrat parser vs LALR vs LL? Good lu…

> I’d like to sit down all university professors who teach compiler courses and teach them a course on what’s relevant.

I don't teach compiler courses, but I'm an academic, and I do keep in touch with industry people to find out what's important for my data analysis course. A couple of big problems with your proposal:

1. Time variation in "what industry wants". This year one thing's hot, the next year it's something else. A bare minimum requirement for any course is that a student taking it in their second year should learn something that's still relevant three years later when they're in the first year of their job.

2. Cross sectional variation. There's no such thing as "what industry wants". Every place wants something different, with only a small subset common to 80% of employers.

Re: Advanced Compilers: Self-Guided Online Course

#77

Post by pfdietz »

samps wrote: post #62
pfdietz wrote: post #57

Nice, although I'd have wanted a segment on compiler testing.

Indeed; I previously had these papers on the list but had to take them out for time this semester: - Finding and understanding bugs in C compilers. Xuejun Yang, Yang Chen, Eric Eide, and John Regehr. PLDI 2011. https://dl.acm.org/citation.cfm?id=1993532 - Compiler validation via equivalence modulo inputs. Vu Le, Mehrdad Afshari, and Zhendong Su. PLDI 2014. https://dl.acm.org/citation.cfm?id=2594334

There are just too many fun things to teach.

More recent paper: yarpgen

https://github.com/intel/yarpgen/blob/main/papers/yarpgen-oo...

Re: Advanced Compilers: Self-Guided Online Course

#78

Post by UncleEntity »

yla92 wrote: post #12

On the related note, what would you guys recommend as an introduction to compilers, say for beginners?

I've been reading "Modern Compiler Design" currently, not too sure how beginner friendly it is though.

Also, haven't made it too far into the book so can't really give a recommendation either way.

Re: Advanced Compilers: Self-Guided Online Course

#79

Post by nicoburns »

UncleEntity wrote: post #70
ibains wrote: post #59

I’ve worked on multiple compilers (optimizations expert) at MSFT on VS and CUDA and gave developed a DSL and worked on Database Compilers. I can’t hire compiler people with right skills. We’re building an IDE and those parsers are written differently, and we use Scala packrat parser combinators. These courses teach very little judgement or industry relevant stuff. When do you use packrat parser vs LALR vs LL? Good lu…

> These courses teach very little judgement or industry relevant stuff. Hasn't that been the debate for, like, ever? Should the universities teach you how to learn or should they teach you how to hit the ground running at your first post-graduation job? I'd say anyone who took phd-level courses on compiler design shouldn't take too much training to become a valuable team member as they've proven they can learn what i…

I feel like "teach you to learn" vs "teach you useful skills"is a false dichotomy, and often just an excuse for poor teaching. They can and should do both. The reasom they don't is because they're so research focussed, which is fine as an option but a problem because there are no or vert few good options for high level academic courses that are more practically focussed.

Re: Advanced Compilers: Self-Guided Online Course

#80

Post by davidpolberger »

37ef_ced3 wrote: post #4

Domain-specific compilers are a bigger field, where there's more opportunity to do something interesting Take C (or some other language) and its mature optimizing compilers as a foundation, and write a program that compiles a high-level description of a domain-specific program into C For example, NN-512 ( https://NN-512.com ) is a compiler that takes as input a simple text description of a convolutional neural net in…

I have just spent the last 13 months significantly reworking a compiler that turns Excel-like formulas into JavaScript. The compiler is used by an app designer, and the formula language is meant to be easy to pick up for people used to spreadsheets. A significant difference compared to Excel is that our compiler features static typing, enabling helpful error messages to be produced at build-time.

(Spreadsheets, on the other hand, tend to try very hard to make sense of types at runtime, using type coercion to turn values of the wrong type into something of the expected type they can work with. That produces surprising results and confuses users. =IF(2, 3, 4) will generally produce 3, because 2 -- which should be a logical/boolean value -- is interpreted as TRUE. We think it's a better idea to warn the user that the first parameter is wrong, and to do that as soon as possible.)

By far the largest challenge with reworking the compiler has been the type system. I have expanded our type system from the four standard spreadsheet types to encompass more than 80, as well as added support for lambdas (for use with functions like SUMIF and FILTER), type inference, parameterized types and union types. The biggest addition is probably an imperative mode, that executes formulas with side-effects in response to events being fired. This is all in service of features we have wanted to add for years, that have been held back by our (previously) simplistic type system.

I did take a compiler class at university, more than 15 years ago, but while that proved very useful when writing the formula parser (an operator-precedence parser, initially straight out of a textbook), type theory was not part of the class. I had to pick up bits and pieces by reading the Java Language Specification (JLS) and by experimenting.

The Cornell class doesn't seem to feature type theory either, which I think is unfortunate. Now that the pendulum has swung, yet again, firmly in the direction of static typing, perhaps static typing will become a bigger part of CS compiler curriculums.

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