Function decode_arguments 

pub fn decode_arguments(
    params: &[SourceParam],
    state: FrameState<'_>,
    layout: ArgumentLayout,
    types: &SourceTypes,
    scope: Option<&str>,
) -> Vec<FrameArgument>

The arguments a function was entered with, read off the stack at its entry point.

Every parameter read here occupies exactly one word: a value type is the value, and a memory or storage reference is a pointer, which memory’s own layout then resolves. A calldata slice of a dynamic type is the exception — it is a pointer and a length, two words, and nothing in the trace proves that width the way the calldata proves the order — so a function taking one reports no arguments rather than words that may be misaligned.