I’m trying to brute force my way through writing a...

# compiler

[Drew Hamilton]

I’m trying to brute force my way through writing a compiler plugin (JVM only for now), but I’m stuck now because I can’t find an InstructionAdapter.ireturn() function. How do I write the JVM IRETURN (integer return) bytecode into my generated code?

[raulraja]

As you are using the transform api to mutate the IR tree you may intercept any expression and replace it with another such as an IrReturnImpl org.jetbrains.kotlin.ir.expressions.impl.IrReturnImpl

[raulraja]

If you want to intercept existing IrReturn nodes in the tree it may look like this
https://github.com/arrow-kt/arrow-meta/blob/e347e266e8b337821de16b960babbea1d6247c50/compiler-plugin/src/main/kotlin/arrow/meta/dsl/codegen/ir/IrSyntax.kt#L644

[raulraja]

And sample call site usage in the context of Arrow Meta which is how I write plugins https://github.com/arrow-kt/arrow-meta/blob/cd197cc5e67d2042afba0617698882968bbee5ee/compiler-plugin/src/main/kotlin/arrow/meta/plugins/proofs/ProofsPlugin.kt#L38

[Drew Hamilton]

I’m looking for the JVM IRETURN bytecode—not IrReturn or anything else with the IR tree! Editing original comment to clarify.

[raulraja]

sorry, thought you meant IR

[raulraja]

IR is coming to Kotlin and I’m not sure what the compiler plans is for those JVM only codegen apis.

[Drew Hamilton]

no problem, appreciate you trying to help. i may refer back to these links if i’m forced to redo this for IR in 6 months 😂

[Drew Hamilton]

To anyone stopping by, the solution was to call instructionAdapter.areturn(Type.INT_TYPE)

[shikasd]

Yeah, most of us plugin writers are forced to write both "old" bytecode codegen and "new" IR for now.
A good example of such a plugin is kotlinx-serialization, I highly recommend you to take a look if you haven't already 🙂