What is 'mov (%r11,%rax,1),%dl'?

[Jeff Law]

On 01/02/2016 09:01 AM, Segher Boessenkool wrote:
> On Sat, Jan 02, 2016 at 10:01:26AM -0500, Jeffrey Walton wrote:
>>     0x000000010048d87b <+174>:   xor    %eax,%eax
>> => 0x000000010048d87d <+176>:   mov    (%r11,%rax,1),%dl
>>
>> (gdb) info registers
>> rax            0x9b7a   0x9b7a
>
> Why is AX not 0 here?  That seems wrong.
Maybe there's an instruction somewhere that jumps to the mov 
instruction.  So %eax would be zero somtimes and some other value other 
times.

jeff