Struct yaxpeax_core::display::location::OperandCursor

pub struct OperandCursor {
    pub operand: u8,
    pub location: Option<u8>,
    pub implicit: bool,
}

OperandCursor is a struct to select some operand and location in an instruction. for some architectures, an operand may be the composition of multiple locations - consider the x86_64 example: dword [rax + rcx * 4 + 0x54320]. this may be the first operand in the enclosing instruction, such as mov dword [rax + rcx * 4 + 0x54320], and would thusly be referenced by OperandCursor { operand: 0, location: None }. rax in the address expression would be distinguished by OperandCursor { operand: 0, location: Some(0) }.

WIP - UI concerns in the above example: 0x54320 may be selectable as a location, but is left to implementors of OperandScroll which will decide if next() and prev() would select or step over that location. For example, if the immediate were small, it may be an offset into a struct, rather than a memory location (such as the base of a static array or jump table).

Fields

operand: u8

location: Option<u8>

implicit: bool

some architectures have instructions where operands and locations may be implied by the instruction in question - architectures with flags regsters are typically good examples of this. in these cases, impicit exists to indicate to whatever uses this cursor that the operand or location being selected may not be explicitly drawn, and that extra work may be necessary to indicate the selection of the referenced element. for example, the x86 je instruction checks the zero flag, but is never explicitly shown. selecting ZF for interaction would be selecting an implicit operand.

open question: how to interact with segment registers in real mode x86 programs, where we probably want to be able to scroll to segment registers, but for other x86 programs, likely do not want to scroll to segment registers. in some cases we might though! is there a nice UI around needing to explicitly select a location, and skipping over it nominally? perhaps skipping in the implementation of OperandScroll and having ui elsewhere to pick OperandCursor explicitly.

Trait Implementations

impl<'a> OperandScroll<(<Arch as Arch>::Instruction, Option<&'a SSA<Arch>>)> for OperandCursor

fn first(
    _instr: &(<x86_64Arch as Arch>::Instruction, Option<&'a SSA<x86_64Arch>>)
) -> OperandCursor

fn next(
    &mut self,
    inst_data: &(<x86_64Arch as Arch>::Instruction, Option<&'a SSA<x86_64Arch>>)
) -> bool

fn prev(
    &mut self,
    inst_data: &(<x86_64Arch as Arch>::Instruction, Option<&'a SSA<x86_64Arch>>)
) -> bool