Function gen_import_call_trampoline 

pub fn gen_import_call_trampoline(
    vmoffsets: &VMOffsets,
    index: FunctionIndex,
    sig: &FunctionType,
    target: &Target,
    calling_convention: CallingConvention,
    experimental_artifact: bool,
) -> Result<CompileOutput<CustomSection>, CompileError>

Singlepass calls import functions through a trampoline.