libmwemu 0.25.2

x86 32/64bits and system internals emulator, for securely emulating malware and other stuff.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28

use crate::emu::Emu;
use crate::{color, regs64};
use iced_x86::Instruction;

// VPSUBB dest, src1, src2 : packed byte-wise wrapping subtraction.
pub fn execute(emu: &mut Emu, ins: &Instruction, _sz: usize, _rep: bool) -> bool {
    emu.show_instruction(color!("Green"), &crate::emu::decoded_instruction::DecodedInstruction::X86(*ins));
    match emu.get_operand_sz(ins, 0) {
        128 => {
            let a = emu.get_operand_xmm_value_128(ins, 1, true).unwrap_or(0).to_le_bytes();
            let b = emu.get_operand_xmm_value_128(ins, 2, true).unwrap_or(0).to_le_bytes();
            let mut r=[0u8;16];
            for i in 0..16 { r[i] = a[i].wrapping_sub(b[i]); }
            emu.set_operand_xmm_value_128(ins, 0, u128::from_le_bytes(r));
        }
        256 => {
            let s1 = emu.get_operand_ymm_value_256(ins, 1, true).unwrap_or_default();
            let s2 = emu.get_operand_ymm_value_256(ins, 2, true).unwrap_or_default();
            let mut a=vec![0u8;32]; s1.to_little_endian(&mut a);
            let mut b=vec![0u8;32]; s2.to_little_endian(&mut b);
            let mut r=[0u8;32];
            for i in 0..32 { r[i]=a[i].wrapping_sub(b[i]); }
            emu.set_operand_ymm_value_256(ins, 0, regs64::U256::from_little_endian(&r));
        }
        _ => unreachable!(""),
    }
    true
}