x29 (FP) is a callee saved register and should be restored on
return. Instead of backing up x29 and restoring it here, back up
sp in a register that we are allowed to overwrite.
This fixes crashes in checkasm on aarch64 since f1b3e13138.
For some reason, gcc builds didn't crash, but clang builds do.
Signed-off-by: Martin Storsjö <martin@martin.st>
This, combined with clobbering the stack space prior to the call,
increases the chances of finding cases where 32 bit parameters
are erroneously treated as 64 bit.
Signed-off-by: Martin Storsjö <martin@martin.st>
Even if MAX_ARGS - 2 (for arm) or MAX_ARGS - 7 (for aarch64) parameters
are passed on the stack to checkasm_checked_call, we actually only
need to store MAX_ARGS - 4 (for arm) or MAX_ARGS - 8 (for aarch64)
parameters on the stack when calling the tested function.
Signed-off-by: Martin Storsjö <martin@martin.st>
