x86-64: fix ZMM register state tracking
Commit Message
On 2018-09-25 11:04 AM, Jan Beulich wrote:
>>>> On 25.09.18 at 05:28, <simon.marchi@ericsson.com> wrote:
>> On 2018-09-18 09:37 AM, Jan Beulich wrote:
>> Thanks for the instructions. There is already a test covering AVX512
>> instructions, so I figured I would add it there. However, I don't
>> have a processor that supports AVX512, so I'm unable to run the test.
>>
>> Here's a patch, can you try to confirm that the test fails without the
>> fix and passes with the fix? I probably screwed up somewhere, but it
>> should be pretty close.
>
> There are two issues here: First of all, unrelated to this patch, the
> construct around line 95 in i386-avx512.exp should look like
>
> if [is_amd64_regs_target] {
> set nr_regs 32
> } else {
> set nr_regs 8
> }
>
> Of course this also affects other tests in here, but without this correction
> the loop you add does nothing at all.
Thanks, this has now been fixed in master.
> And then that very loop and the i386-avx512.c addition are not in sync,
> and I'm not sure which way you meant it to be: Either in the C file all 16
> upper ZMM registers need to be set identically (not just ZMM16), or
> there should be no loop.
Woops. Testing only zmm0 and zmm16 will be enough I think.
> Furthermore I think the C code addition and hence the test will need to
> be x86-64-specific, as registers ZMM8 and higher are inaccessible in
> 32-bit mode.
Good point.
Here's the revised version with this fixed. I am not sure about the output
for zmm0 though.
From cd9f3e298a3a516298d3fea15ba80b3eaa33cc7c Mon Sep 17 00:00:00 2001
From: Simon Marchi <simon.marchi@ericsson.com>
Date: Mon, 24 Sep 2018 23:28:28 -0400
Subject: [PATCH] AVX512 test
---
gdb/testsuite/gdb.arch/i386-avx512.c | 7 +++++++
gdb/testsuite/gdb.arch/i386-avx512.exp | 10 ++++++++++
2 files changed, 17 insertions(+)
--
2.19.0
Comments
>>> Simon Marchi <simon.marchi@ericsson.com> 10/02/18 9:20 PM >>>
>On 2018-09-25 11:04 AM, Jan Beulich wrote:
>>>>> On 25.09.18 at 05:28, <simon.marchi@ericsson.com> wrote:
>>> On 2018-09-18 09:37 AM, Jan Beulich wrote:
>>> Thanks for the instructions. There is already a test covering AVX512
>>> instructions, so I figured I would add it there. However, I don't
>>> have a processor that supports AVX512, so I'm unable to run the test.
>>>
>>> Here's a patch, can you try to confirm that the test fails without the
>>> fix and passes with the fix? I probably screwed up somewhere, but it
>>> should be pretty close.
>>
>> There are two issues here: First of all, unrelated to this patch, the
>> construct around line 95 in i386-avx512.exp should look like
>>
>> if [is_amd64_regs_target] {
>> set nr_regs 32
>> } else {
>> set nr_regs 8
>> }
>>
>> Of course this also affects other tests in here, but without this correction
>> the loop you add does nothing at all.
>
>Thanks, this has now been fixed in master.
Ah, good to know.
>Here's the revised version with this fixed. I am not sure about the output
>for zmm0 though.
I'll give this a go and adjust if need be, but it'll likely take me a couple of
days to get to it. I take it that ...
>--- a/gdb/testsuite/gdb.arch/i386-avx512.c
>+++ b/gdb/testsuite/gdb.arch/i386-avx512.c
>@@ -249,6 +249,13 @@ main (int argc, char **argv)
>move back to array and check values. */
>move_zmm_data_to_memory ();
>asm ("nop"); /* sixth breakpoint here */
>+
>+ asm ("vpternlogd $0xff, %zmm0, %zmm0, %zmm0");
>+#ifdef __x86_64__s
... the trailing s here simply is a typo.
Jan
On 2018-10-03 10:30, Jan Beulich wrote:
>> Here's the revised version with this fixed. I am not sure about the
>> output
>> for zmm0 though.
>
> I'll give this a go and adjust if need be, but it'll likely take me a
> couple of
> days to get to it. I take it that ...
There's no rush, thanks for helping.
>> --- a/gdb/testsuite/gdb.arch/i386-avx512.c
>> +++ b/gdb/testsuite/gdb.arch/i386-avx512.c
>> @@ -249,6 +249,13 @@ main (int argc, char **argv)
>> move back to array and check values. */
>> move_zmm_data_to_memory ();
>> asm ("nop"); /* sixth breakpoint here */
>> +
>> + asm ("vpternlogd $0xff, %zmm0, %zmm0, %zmm0");
>> +#ifdef __x86_64__s
>
> ... the trailing s here simply is a typo.
Arrrg, indeed.
Simon
@@ -249,6 +249,13 @@ main (int argc, char **argv)
move back to array and check values. */
move_zmm_data_to_memory ();
asm ("nop"); /* sixth breakpoint here */
+
+ asm ("vpternlogd $0xff, %zmm0, %zmm0, %zmm0");
+#ifdef __x86_64__s
+ asm ("vpternlogd $0xff, %zmm0, %zmm0, %zmm16");
+#endif
+ asm ("vzeroupper");
+ asm ("nop"); /* seventh breakpoint here */
}
return 0;
@@ -174,3 +174,13 @@ for { set r 0 } { $r < $nr_regs } { incr r } {
".. = \\{f = \\{[expr $r + 30], [expr $r.125 + 30], [expr $r.25 + 20], [expr $r.375 + 20], [expr $r.5 + 10], [expr $r.625 + 10], [expr $r.75 + 10], [expr $r.875 + 10]\\}\\}.*" \
"check contents of zmm_data\[$r\] after writing XMM regs"
}
+
+gdb_test "break [gdb_get_line_number "seventh breakpoint here"]" \
+ "Breakpoint .* at .*i386-avx512.c.*" \
+ "set seventh breakpoint in main"
+gdb_continue_to_breakpoint "continue to seventh breakpoint in main"
+gdb_test "print \$zmm0.v16_int32" "= {-1, -1, -1, -1, 0 <repeats 12 times>}"
+
+if { $nr_regs >= 16 } {
+ gdb_test "print \$zmm16.v16_int32" "= {-1 <repeats 16 times>}"
+}