Raw bytecode

Targets and code blocks cover the common cases. Underneath, app.reseam.patch.dex exposes methods and classes as handles, instructions as data, and registers as numbers. Reach it through target.method, target.classDef, bytecode, or the custom target constructors.

import app.reseam.patch.dex.Opcode

val method = configureDownloads.method
val index = method.indexOfFirstInstruction { opcode == Opcode.IGET && fieldRef?.fieldType == Type.Int }
    ?: error("no int field read")

method.addInstructions(index) {
    constInt(0, 1)
    returnValue(0)
}

Method reads instructions, registers, and references, searches by opcode, string, literal, call, or predicate, and mutates: insert, replace, remove, replaceBody, alwaysReturn, growLocalRegisters. DexClass lists methods and fields and can add, remove, or re-flag them. Instruction extension properties (opcode, regA, methodRef, stringValue, literal, ...) read the engine's instruction type.

The builder inside addInstructions { } is named after the Dalvik instructions: constInt, constString, move*, invoke*, iget*/iput*/sget*/sput* with *Typed variants, newInstance, checkCast, goto(label), if*, return*. label(name) marks a branch target; offsets are computed on build. All registers are v-numbers, and invokes the 35c format cannot encode are lowered to range form on insertion. Everything is listed in the reference.

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