[PATCH 1/1] Cygwin: signal: Fix stabilize_sig_stack/setjmp/longjmp on AArch64

[Corinna Vinschen]

On Feb 19 08:44, Igor Podgainoi wrote:
> This commit fixes the AArch64 implementation of the following three
> functions: stabilize_sig_stack, setjmp and longjmp.
> 
> Changes made:
> 
> * Fixed code indentation in all three functions.
> * Corrected some comments and added additional ones.
> * Added missing SEH directives.
> * Changed the locking algorithm in stabilize_sig_stack to Test and
>   Test-and-Set (TTAS).
> * Stopped returning a value in x0 in stabilize_sig_stack to avoid
>   unnecessary clobbering. This should make it more similar to the
>   x86_64 version.
> * Using x10 instead of x0 in setjmp and longjmp where needed as per
>   the previous change.
> * Fixed bug in setjmp where the SP value after the prologue was used,
>   instead of the original one.
> * Fixed bug in setjmp where the stackptr was saved at the wrong offset
>   into jmp_buf (should be 0).
> * Now saving and restoring x0 in setjmp and x0/x1 in longjmp around the
>   call to stabilize_sig_stack. This should make it more similar to the
>   x86_64 version.
> * Removed the prologue and epilogue in longjmp, as the function never
>   returns.
> * Changed logic in longjmp to take the return value directly from the
>   second argument. This should make it more similar to the x86_64
>   version.
> * Fixed bug in longjmp where the TLS stack pointer restoration used an
>   invalid base register.
> * Using zero registers instead of an immediate 0 where possible.
> 
> Tests fixed on AArch64:
> winsup.api/mmaptest02.exe
> winsup.api/mmaptest03.exe
> winsup.api/ltp/mmap05.exe
> 
> Signed-off-by: Igor Podgainoi <igor.podgainoi@arm.com>
> ---
>  winsup/cygwin/scripts/gendef | 277 ++++++++++++++++++-----------------
>  1 file changed, 142 insertions(+), 135 deletions(-)

Pushed on top of Thirumalai's patches.


Thanks,
Corinna