MIPS: Only use current_stack_pointer on GCC

Unfortunately, Clang did not have support for "sp" as a global register
definition, and was crashing after the addition of current_stack_pointer.
This has been fixed in Clang 14, but earlier Clang versions need to
avoid this code, so add a versioned test and revert back to the
open-coded asm instances. Fixes Clang build error:

fatal error: error in backend: Invalid register name global variable

Fixes: 200ed341b864 ("mips: Implement "current_stack_pointer"")
Reported-by: Nathan Chancellor <[email protected]>
Reviewed-by: Nathan Chancellor <[email protected]>
Link: https://lore.kernel.org/lkml/[email protected]
Cc: Thomas Bogendoerfer <[email protected]>
Cc: Marc Zyngier <[email protected]>
Cc: Guenter Roeck <[email protected]>
Cc: Yanteng Si <[email protected]>
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
Reviewed-by: Nick Desaulniers <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

0 files changed, 0 insertions, 0 deletions