On Fri, Jul 6, 2012 at 10:49 AM, Feng LI <nemokingdom@gmail.com> wrote: > So under x86_64 machine, I could do a > Shl %rax 32 safely without being truncated? Yes. > Still , why the suffix q is removed in the disassembled code if they are the > same? > You can get suffix by adding -Msuffix to objdump. -- H.J.