assembly translation ignores clang asm variants

[oinoom]

the following C code:

int mul2_3(int var64)
{
    int out;
    int dummy = 2;
    asm("add {%0, %2 | %2 %0}\n\t"
        "add %1, %1"
        : "=r"(out)
        : "r"(dummy), "0"(var64));
    return out;
}

will have the following LLVM assembly string: "add $($0, $2 $| $2 $0$)\n\tadd $1, $1"

which gets translated into the following Rust

#[no_mangle]
pub unsafe extern "C" fn rust_mul2_3(mut var64: libc::c_int) -> libc::c_int {
    let mut out: libc::c_int = 0;
    let mut dummy: libc::c_int = 2 as libc::c_int;
    let fresh9 = &mut out;
    let fresh10;
    let fresh11 = var64;
    asm!(
        "add ({0}, {0} | {0} {0})\n\tadd {1}, {1}", inlateout(reg)
        c2rust_asm_casts::AsmCast::cast_in(fresh9, fresh11) => fresh10, inlateout(reg)
        dummy => _, options(preserves_flags, pure, readonly, att_syntax)
    );
    c2rust_asm_casts::AsmCast::cast_out(fresh9, fresh11, fresh10);
    return out;
}

In these cases it will be necessary to parse and identify which variant is which at some level of confidence, and choose an option to output.