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Interesting, do you mean that one can use CPS transforms instead of SSA? I've never written a non-trivial code generator, so please excuse me if the question seem dumb.

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SSA and CPS are actually the same thing, in some fashion. I'm not 100% up to speed on the details myself, but as I understand it, CPS is the functional-language form and SSA is the imperative-language form.

A good reference is Andrew Appel's "SSA is functional programming"[1] which discusses the similarities. There are practical differences between SSA, ANF, and CPS, but the similarity at a high level is quite strong.

[1] http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.34.3...

The basic result is that if you just CPS-convert a language without first-class continuations (so, no call-CC), all of that is interchangeable with SSA and any optimization written against one IR can be rewritten fairly mindlessly against the other IR.

If you allow first-class continuations in user programs, though, all bets are off and CPS is more expressive.

Richard Kelsey wrote the paper that talks about how to convert between CPS and SSA forms, along with the first-class continuation limitation mentioned above:

http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.3.67...

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