[jbeulich@dus-dev-sles15v ~]$ gcc -Wall -W -o vzero{,.s} && gdbx ./vzero
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Reading symbols from ./vzero...done.
(gdb) break main
Breakpoint 1 at 0x400497
(gdb) r
Starting program: /home/jbeulich/vzero 

Breakpoint 1, 0x0000000000400497 in main ()
(gdb) disp/i $pc
2: x/i $pc
=> 0x400497 <main>:	vpternlogd zmm0,zmm0,zmm0,0xff
(gdb) si
0x000000000040049e in main ()
2: x/i $pc
=> 0x40049e <main+7>:	vpternlogd zmm16,zmm0,zmm0,0xff
(gdb) 
0x00000000004004a5 in main ()
2: x/i $pc
=> 0x4004a5 <main+14>:	vzeroupper 
(gdb) print $zmm0.v16_int32
$1 = {-1 <repeats 16 times>}
(gdb) print $zmm16.v16_int32
$2 = {-1 <repeats 16 times>}
(gdb) si
0x00000000004004a8 in main ()
2: x/i $pc
=> 0x4004a8 <main+17>:	xor    eax,eax
(gdb) print $zmm16.v16_int32
$3 = {-1 <repeats 16 times>}
(gdb) q
A debugging session is active.

	Inferior 1 [process 56857] will be killed.

Quit anyway? (y or n) y