RE: [PATCH] Fix is_amd64_regs_target check in i386-avx512.exp

["Metzger, Markus T" <markus dot t dot metzger at intel dot com>]

Hello Simon,

> As reported by Jan here:
> 
>   https://sourceware.org/ml/gdb-patches/2018-09/msg00831.html
> 
> the check that sets the number of available registers seems backwards.
> I can't test this patch however, since I don't have access to a cpu with AVX512.
> Could somebody perhaps from Intel, or somebody else that has access to such
> CPU, take a look?

It indeed is backwards.

The current test fails badly when run with -m32.

 
> gdb/testsuite/ChangeLog:
> 
> 	* gdb.arch/i386-avx512.exp: Fix setting of nr_regs based on
> 	is_amd64_regs_target.
> ---
>  gdb/testsuite/gdb.arch/i386-avx512.exp | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/gdb/testsuite/gdb.arch/i386-avx512.exp
> b/gdb/testsuite/gdb.arch/i386-avx512.exp
> index de2f62c3e1f..f27af534cfd 100644
> --- a/gdb/testsuite/gdb.arch/i386-avx512.exp
> +++ b/gdb/testsuite/gdb.arch/i386-avx512.exp
> @@ -93,9 +93,9 @@ gdb_test "break [gdb_get_line_number "third breakpoint
> here"]" \  gdb_continue_to_breakpoint "continue to third breakpoint in main"
> 
>  if [is_amd64_regs_target] {
> -    set nr_regs 8
> -} else {
>      set nr_regs 32
> +} else {
> +    set nr_regs 8
>  }
> 
>  for { set r 0 } { $r < $nr_regs } { incr r } {
> --
> 2.19.0

With your patch, the test only fails for zmm registers due to broken XSAVE
handling.  This is fixed by Jan's patch.  With both patches together, the test
passes for -m32.

Regards,
Markus.

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