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by the-alt-one 1601 days ago
Are the techniques used different in such a case? Shouldn't it just be the same?

Basically F(C) = R such that eval_C(C) = eval_R(R) where = means something like "discernible effects".

Wouldn't an optimization pass be a transpiler then?
2 comments
chrisseaton 1601 days ago
It’s just a slightly more descriptive term that gives you the information that it’s high-to-high.

It’s like saying cheese burger instead of burger - it’s a little more info. It’s not saying that it’s not a burger as well, or that the techniques involved aren’t broadly the same.

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detaro 1601 days ago
A bunch of things a compiler "going downwards" needs to do don't apply, e.g. you don't need to worry about registers and things like that. And there's potentially more complex concepts to map to instead of just breaking source-language concepts down.

Haven't seen that terminology applied to individual passes.

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the-alt-one 1601 days ago
Most compilers don't have to worry about registers nowadays, since they compile to LLVM or C.
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detaro 1601 days ago
It was just an example of a task. Also, "compile to LLVM" is very much "LLVM is part of the compiler, and thus worries about registers". Compile to C is (depending on source language and exactly which definitions you use) potentially also a transpiler.
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the-alt-one 1600 days ago
Eh, I don't really see what this term gives us... So C2Rust is a compiler too, since Rust is compiled to LLVM?
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chrisseaton 1600 days ago
> So C2Rust is a compiler too

All transpilers are compilers.

C2Rust is a transpiler and a compiler.

Not all compilers are transpilers.

Graal for example is a compiler but not a transpiler.

Just like all cheese burgers are burgers but not all burgers are cheese burgers. Nobody questions the term ‘cheese burger’ because we already have the word ‘burger’.

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the-alt-one 1600 days ago
Yeah, because a cheese burger has cheese. What does a transpiler have? What is the common factor between all transpilers? Who decides on this layering of which languages are higher level or lower level? C2Rust doesn't call itself a transpiler, it calls itself a translator.

This term seems completely useless to me.

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