register_info.rs

use gdbstub::target;
use gdbstub::target::ext::register_info::Register;

use crate::gdb::Emu;

// This implementation is for illustrative purposes only. If the .xml target description is used, the qRegisterInfo Packet is not necessary. (Note: This is an LLDB specific packet)

// We have r0-pc from 0-16 but cpsr is at offset 25*4 in the 'g'/'G' packet, so we add 8 padding
// registers here. Please see gdbstub/examples/armv4t/gdb/target_description_xml_override.rs for
// more info.
const MAX_REG_NUM: u8 = 17 + 8;
const SP: u8 = 13;
const PC: u8 = 15;
const CPSR: u8 = 25;
const REG_NAMES: &[&str] = &[
    "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "sp", "lr",
    "pc", "padding", "padding", "padding", "padding", "padding", "padding", "padding", "padding",
    "padding", "cpsr",
];

impl target::ext::register_info::RegisterInfo for Emu {
    fn get_register_info(&mut self, reg_id: u8) -> Result<Option<Register>, Self::Error> {
        match reg_id {
            0..=MAX_REG_NUM => {
                let name = REG_NAMES[reg_id as usize];
                let encoding = if reg_id < 16 || reg_id == CPSR {
                    "uint"
                } else {
                    "vector"
                };
                let format = if reg_id < 16 || reg_id == CPSR {
                    "hex"
                } else {
                    "vector-uint8"
                };
                let set = if reg_id < 16 || reg_id == CPSR {
                    "General Purpose Registers"
                } else {
                    "Floating Point Registers"
                };
                let generic = if reg_id == SP {
                    Some("sp")
                } else if reg_id == PC {
                    Some("pc")
                } else {
                    None
                };
                Ok(Some(Register {
                    name,
                    alt_name: name,
                    bitsize: 32,
                    offset: (reg_id as u16) * 4,
                    encoding,
                    format,
                    set,
                    gcc: None,
                    dwarf: Some(reg_id as u16),
                    generic,
                    container_regs: None,
                    invalidate_regs: None,
                }))
            }
            // Will end the 'qRegisterInfo' query
            _ => Ok(None),
        }
    }
}