Function instr_writes_to_exact_reg 

pub unsafe extern "C" fn instr_writes_to_exact_reg(
    instr: *mut instr_t,
    reg: reg_id_t,
    flags: dr_opnd_query_flags_t,
) -> bool_

Assumes that \p reg is a DR_REG_ constant. Returns true iff at least one of \p instr’s destination operands is the same register (not enough to just overlap) as \p reg. Which operands are considered to be accessed for conditionally executed instructions are controlled by \p flags.