neo-decompiler 0.11.0

Neo N3 NEF decompiler: parse, disassemble, lift bytecode to high-level pseudocode and C# skeletons, with a CLI, JSON reports, and optional WebAssembly bindings.
Documentation 
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use crate::instruction::{Instruction, OpCode};

use effects::stack_effect_for_arg_inference;
use indexed::{apply_pick, apply_reversen, apply_roll, apply_xdrop};
use state::EntryStack;

mod effects;
mod indexed;
mod state;

pub(super) fn estimate_required_entry_stack_depth(instructions: &[Instruction]) -> Option<usize> {
    let mut state = EntryStack::default();
    let mut saw_supported_opcode = false;

    for instruction in instructions {
        if instruction.opcode == OpCode::Ret {
            break;
        }
        apply_instruction_for_arg_inference(instruction, &mut state)?;
        saw_supported_opcode = true;
    }

    saw_supported_opcode.then_some(state.required_entry_depth())
}

fn apply_instruction_for_arg_inference(
    instruction: &Instruction,
    state: &mut EntryStack,
) -> Option<()> {
    match instruction.opcode {
        OpCode::Pick => apply_pick(state),
        OpCode::Roll => apply_roll(state),
        OpCode::Xdrop => apply_xdrop(state),
        OpCode::Reversen => apply_reversen(state),
        _ => {
            let effect = stack_effect_for_arg_inference(instruction, state.stack())?;
            state.pop_count(effect.pops);
            state.push_all(effect.pushes);
            Some(())
        }
    }
}