RE: gdb prints only 128 bits of a YMM register (AVX)

Hello Laurent,

I did not understand how you are trying to see register values from the example bellow.

Have you used print $ymm0 or info register?

Thanks and regards,
-Fred

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Laurent ML
Sent: Monday, July 27, 2015 2:48 PM
To: [email protected]
Subject: gdb prints only 128 bits of a YMM register (AVX)

Hello,

I have created a small C program that uses AVX extensions, and I have compiled it with options -03 -mavx.
Next I used GDB to print the content of YMM registers, but each time I print the content of one of the YMM register, gdb prints only the highest 128 bits of the registers:

Breakpoint 1, 0x0000000000400a70 in func2_compare_32bitsPack ()
$1 = ">"
$2 = {0xffffffffffff00000000000000000000, 0x00000000000000000000000000000000}
$3 = {0x0000000000006e6f73697261706d6f43, 0x00000000000000000000000000000000}
$4 = {0x00000000000000000000000000000000, 0x00000000000000000000000000000000}
$5 = {0x000000000000ff000000000000ffffff, 0x00000000000000000000000000000000}
$6 = {0x00000000000000000000000000000000, 0x00000000000000000000000000000000}
$7 = {0x00000000000000000000000000000000, 0x00000000000000000000000000000000}
$8 = {0x00000000000000000000000000000000, 0x00000000000000000000000000000000}
$9 = {0x00000000000000000000000000000000, 0x00000000000000000000000000000000}
$10 = {0x00000000000000000000000000000000, 0x00000000000000000000000000000000}
$11 = {0x00000000000000000000000000000000, 0x00000000000000000000000000000000}
$12 = {0x00000000000000000000000000000000, 0x00000000000000000000000000000000}
$13 = {0x00000000000000000000000000000000, 0x00000000000000000000000000000000}
$14 = {0x00000000000000000000000000000000, 0x00000000000000000000000000000000}
$15 = {0x00000000000000000000000000000000, 0x00000000000000000000000000000000}
$16 = {0x00000000000000000000000000000000, 0x00000000000000000000000000000000}
$17 = {0x00000000000000000000000000000000, 0x00000000000000000000000000000000}

Is there a way to get the last part of the register ?

I used gdb on EL7 :
$ gdb -v
GNU gdb (GDB) Red Hat Enterprise Linux 7.6.1-64.el7

Thanks for your help.
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